CN108686490A

CN108686490A - A kind of fuel gas desulfurization gas wash tower and desulfurization and dust-removal method

Info

Publication number: CN108686490A
Application number: CN201710237280.1A
Authority: CN
Inventors: 刘忠生; 李磊; 刘淑鹤; 李欣; 王昊辰; 韩天竹; 王海波
Original assignee: China Petroleum and Chemical Corp; Sinopec Dalian Research Institute of Petroleum and Petrochemicals
Current assignee: Sinopec Dalian Petrochemical Research Institute Co ltd; China Petroleum and Chemical Corp
Priority date: 2017-04-12
Filing date: 2017-04-12
Publication date: 2018-10-23
Anticipated expiration: 2037-04-12
Also published as: CN108686490B

Abstract

The invention discloses a kind of fuel gas desulfurization gas wash tower and desulfurization and dust-removal methods.Liquid bath area is held in the fuel gas desulfurization gas wash tower of the present invention, including pretreatment unit, advanced treatment unit and bottom of tower, and the pretreatment unit is connected to advanced treatment unit by flue.The pretreatment unit is from top to bottom followed successively by chilling spraying zone, level-one spraying zone, venturi grid scrubbing section;The advanced treatment unit is followed successively by that liquid bath area is held at middle part, liquid bath area, three-level spraying zone, mist eliminating zone and flue gas emission area are held in two level spraying zone, top from the bottom to top;This invention removes " white cigarette long queue " phenomenon of wet desulphurization, " white cigarette " phenomenon of flue gas emission mouth substantially reduces;The triple functions of flue gas ash removal, desulfurization and depth demisting are realized in a tower, each functional area coordinated mutually promotes, significantly reduces the floor space of equipment, significantly reduces the expense needed for plant construction, transformation.

Description

A kind of fuel gas desulfurization gas wash tower and desulfurization and dust-removal method

Technical field

The invention belongs to industrial waste gas purifying field, it is related to a kind of fuel gas desulfurization gas wash tower and desulfurization and dust-removal method.

Background technology

Contain sulfur dioxide and dust in the flue gas of boiler smoke and plant emissions, sulfur dioxide and dust are air dirts The main composition dust of object is contaminated, sulfur dioxide is the main reason for forming acid rain, and the smaller dust of grain size is the haze to be formed crime One of stalwart chief culprit.

Wet desulphurization is high with desulfurization degree, device is reliable for operation, simple operation and other advantages, thus the existing cigarette in countries in the world Desulfurization technology is mainly based on wet desulphurization.Traditional Wet Flue Gas Desulfurization Technique mainly has limestone-gypsum method, Dual alkali de- Sulphur, sodium alkali desulfurization, ammonia process of desulfurization method etc..Above-mentioned flue gas desulfurization technique mainly uses countercurrent spray, and alkaline slurry is from desulfurizing tower Top is sprayed, and free settling is contacted with flue gas adverse current under the effect of gravity realizes desulphurization reaction.

The grain size of dust is smaller in flue gas, and most of between 0.1 ~ 200 μm, flue gas ash removal technology is mainly cloth bag at present Formula dedusting technology, electrostatic precipitator technology, wet dust collection technology.Due to containing moisture in flue gas, dust is in fiber bag precipitator Moisture absorption is cohered on filter bag, blocks the hole of filter bag, thus needs that frequently filter bag is cleared up or replaced, and fiber bag precipitator is answered With being extremely limited;The major defect of electrostatic precipitator is that cost is higher, and installation is safeguarded, manages requirement strictly, and height is needed Buckling electricity and commutation control equipment, power consumption is higher, and floor space is larger;Wet dust collection technology mainly removes cigarette by shower water After being combined with dust still chimney can be discharged with flue gas in the dust carried in gas, the smaller drop of grain size.

On December 11st, 2015 Environmental Protection Department, National Development and Reform Commission, National Energy Board joint publication"It is comprehensively real Apply coal-burning power plant's minimum discharge and reducing energy consumption programme of work"(Ring sends out [2015]No. 164), regulation is to the year two thousand twenty whole nation in scheme Strive realizing ultra-clean discharge, i.e., under the conditions of benchmark oxygen content 6%, exhaust gas dust in all coal-burning power plants for having transformation condition ≯10mg/Nm³, SO₂≯35mg/Nm³.Existing wet desulphurization device is difficult to meet the requirement of discharge standard.

Large-scale promotion application with wet type desulfurizing technology in China, one of wet type desulfurizing technology apparent and be difficult to gram The shortcomings that taking gradually reveals, which is exactly to discharge flue gas to will produce " white cigarette " phenomenon in throat, or even can form number " the white cigarette long queue " of kilometer, strong visual impact is brought to people, ground there is also " dust-shower " phenomenon sometimes.In addition, a large amount of Steam in air, causes the waste of water resource from chimney direct emission.The main component of " white cigarette " is vapor, main source There are two aspects:First, the demister efficiency of flue gas desulfurization device is low, small water droplet is still carried in the flue gas after demisting(It is i.e. supersaturated Water);Second is that temperature reduces after high-temperature flue gas discharge, the saturated water amount entrained by flue gas is caused to reduce, vapor precipitation condenses into Small water droplet forms " white cigarette ".So how to eliminate the problem that " white cigarette " phenomenon is urgently to be resolved hurrily at present.

Invention content

In view of the deficiencies of the prior art, a kind of fuel gas desulfurization gas wash tower of present invention offer and desulfurization and dust-removal method, the present invention Fuel gas desulfurization gas wash tower pretreatment unit realize flue gas chilling, desulfurization and dedusting, advanced treatment unit realize flue gas Deep desulfuration, dedusting and demisting, meet the requirement of national ultra-clean discharge, thoroughly remove the supersaturation water carried in flue gas, Substantially reduce " white cigarette " phenomenon after flue gas emission, the method for the present invention flow is short, equipment is few, floor space is few, has wide Application prospect.

Liquid bath area is held in the fuel gas desulfurization gas wash tower of the present invention, including pretreatment unit, advanced treatment unit and bottom of tower, pre- to locate Reason unit is connected to advanced treatment unit by flue, and three constitutes " Jiu shapes " Double-Tower Structure;Pretreatment unit is from top to bottom It is followed successively by chilling spraying zone, level-one spraying zone, venturi grid scrubbing section;Advanced treatment unit is followed successively by middle part and holds from the bottom to top Liquid bath area, three-level spraying zone, mist eliminating zone and flue gas emission area are held in liquid bath area, two level spraying zone, top.

The fuel gas desulfurization gas wash tower of the present invention, the pretreatment unit is 0.2 ~ 1 with advanced treatment unit tower diameter ratio, excellent It is selected as 0.4 ~ 1.

It is connected with flue gas pipeline at the top of the chilling spraying zone;Chilling spraying zone axis sets up several opening upwards Or downward heavy caliber atomizer, each heavy caliber atomizer are connected with spray pipe I, the entrance of heavy caliber atomizer connects The tower diameter ratio of head tube diameter and chilling spraying zone is 0.005 ~ 0.1, preferably 0.01 ~ 0.06;The heavy caliber atomizer Spray angles are 60 ~ 150 °, and optimized angle is 120 ~ 150 °;The water mist of spray is in solid conical, and conical bottom surface diameter is big In the tower diameter of chilling spraying zone;Preferably at least include that a pair of openings is opposite(One Open Side Down, another opening upwards)It is big Bore atomizer, more preferably 2 ~ 3 pairs;Two conical surfaces that the opposite heavy caliber atomizer of each pair of opening sprays out are mutual The plane for being formed and covering entire tower diameter is mutually hit, the plane is comprehensive to flue gas progress effectively to be intercepted, and realizes the chilling drop of flue gas Temperature, and remove the dust and sulfur dioxide carried in flue gas.Every spray pipe I can connect 1 heavy caliber atomizer or 2 opposite heavy caliber atomizers of opening direction;The inlet attack caliber of the heavy caliber atomizer generally can be DN50~200。

One or more layers spray pipe II is arranged in the level-one spraying zone, when Multi-layer sprinkling pipeline II is set, spray tube The distance between line II is 0.5 ~ 5m, and preferred distance is 1 ~ 2.5m;The spray pipe II connection loop slurry pipeline II, spray It is provided with multiple atomizers on shower pipe line II;The level-one spraying zone is for loop slurry to be atomized, the small liquid after atomization Drop and flue gas current contacting, remove the dust and sulfur dioxide carried in flue gas.

The venturi grid scrubbing section is provided with one or more layers venturi grid, when using multilayer venturi grid Two layers neighbouring of venturi grid is staggered;The venturi grid is enhancing loop slurry to dust in flue gas And SO₂Washing effect, increase to dust and SO₂Removal efficiency.

It holds liquid bath area and is separately connected alkaline solution line I, bottom of tower overflow line and liquid close to tower wall side in the bottom of tower Position meter I;Flow control valve is set on the alkaline solution line I, it is adjusted for filling alkaline solution into bottom of tower slurries PH value;The bottom of tower overflow line is used for the automatic-discharging bottom of tower slurries when the liquid level of bottom of tower slurries is more than setting value, avoids Bottom of tower slurry plugs flue;Hold liquid bath area bottom connection bottom of tower slurries extraction pipeline, the extraction of bottom of tower slurries in the bottom of tower Pipeline is connected with bottom of tower circulating pump, realize bottom of tower slurries chilling spraying zone and level-one spraying zone circulated sprinkling.

The middle part holds liquid bath area and several riser I is arranged, and the flue gas from pretreatment unit enters through flue Advanced treatment unit enters two level spraying zone by riser I;Hold the one or more overflow pipes of liquid bath area setting in the middle part I, overflow pipe I height are less than riser I height, and middle part, which holds the circulation fluid in liquid bath and enters bottom of tower by overflow pipe I, holds liquid bath area; The middle part holds liquid bath bottom and is connected with middle part circulation fluid extraction pipeline, and middle part circulation fluid extracts pipeline and middle part circulating pump phase out Even, circulated sprinkling of the circulation fluid in two level spraying zone in the middle part of realizing.

It holds liquid bath area and is connected with fresh water pipeline I and alkaline solution line II close to tower wall side in the middle part;It is described Fresh water pipeline I on flow control valve is set, according to bottom of tower liquid level gauge I feedback Signal Regulation fresh water flow, be used for The liquid level in control tower Di Chi liquid baths area;It is provided with flow control valve on the alkaline solution line II, according to middle part circulation fluid The Signal Regulation for the pH meter feedback being arranged on extraction pipeline holds the flow for the alkaline solution that liquid bath area fills to middle part.

One or more layers spray pipe III is arranged in the two level spraying zone, when Multi-layer sprinkling pipeline III is set, spray The distance between pipeline III is 0.5 ~ 5m, and preferred distance is 1 ~ 2.5m;Liquid pipe is recycled in the middle part of the spray pipe III connections Line is provided with multiple atomizers on spray pipe III;The two level spraying zone is for circulation fluid to be atomized, after atomization Droplet is contacted with flue gas adverse current, to carrying out depth dedusting and desulfurization in flue gas.

The top holds liquid bath area and several riser II is arranged, and flue gas enters three-level spraying zone by riser II;On The one or more overflow pipe II of Bu Chi liquid baths area setting, overflow pipe II height are less than riser II height, and top is held in liquid bath Circulating cooling liquid is by overflow pipe II into two level spraying zone;It holds liquid bath bottom and is connected with top circulating cooling liquid extraction pipe in top Line, top circulating cooling liquid extract out pipeline connect coolant recirculation pump, realize circulating cooling liquid three-level spraying zone cycle Spray.

It holds liquid bath area and is connected with fresh water pipeline II and alkaline solution line III close to tower wall side in the top;Institute Flow control valve is set on the fresh water pipeline II stated, according to the flow of the Signal Regulation fresh water of liquid level gauge II feedbacks, is used for Hold the liquid level of liquid bath in control top;It is provided with flow control valve on the alkaline solution line III, according to top circulating cooling The Signal Regulation for the pH meter feedback being arranged on liquid extraction pipeline holds the flow for the alkaline solution that liquid bath area fills to top.

One or more layers spray pipe IV is arranged in the three-level spraying zone, when Multi-layer sprinkling pipeline IV is set, spray tube The distance between line IV is 0.5 ~ 5m, and preferred distance is 1 ~ 2.5m;The spray pipe IV connection loop slurry pipeline IV, spray It is provided with multiple atomizers on shower pipe line IV;The three-level spraying zone be used for by from top hold the circulating cooling of liquid bath Liquid mist, the circulating cooling liquid drop after atomization are contacted with flue gas adverse current, to carrying out cooling down and depth dedusting in flue gas, taking off Sulphur.

The three-level spraying zone is preferably connected by reverse taper deformation diameter with mist eliminating zone, and the mist eliminating zone is sprayed with three-level The tower diameter ratio for drenching area is 1.2 ~ 3.

The mist eliminating zone is provided with demister, and demister includes several demisting components arranged side by side, each demisting component Include riser and outer barrel, outer barrel is arranged in the outside of riser, preferably on the same axis with riser;Riser is fixed On mist eliminating zone tower tray, the top setting capping plate of riser;Several rectification channels, rectification are uniformly arranged on the circumference of riser Channel is embedded in along the tangential direction level of riser outer wall, side wall I and riser tube wall phase of the rectification channel close to outer barrel side It cuts, another side wall II intersects with riser tube wall, and each rectification channel direction of rotation is identical;Rectification channel roof and capping plate are neat Flat, bottom is intersected with riser tube wall.

In the demister, the generally setting 1 ~ 12 of rectification channel, preferably 4-8.The wall thickness in rectification channel preferably with The wall thickness of riser is identical.

In the demister, the length l in rectification channel is the length of side wall II, and width w is between the two side of rectification channel Maximum horizontal range, maximum normal distances of the height h between rectification channel roof and bottom;Wherein length l be width w 2 ~ 5 times, preferably 3 ~ 4 times;The cross sectional shape in rectification channel be rectangle, ellipse, circle, it is trapezoidal or semicircle etc. in one kind or Several combinations, one or more of preferably rectangular, oval or round combination.The size in rectification channel is according to actual work Condition or design requirement, are determined by those skilled in the art, and the height h in such as rectification channel is generally 20~600mm, excellent It is selected as 100~300mm;The width w in rectification channel is generally 10~200mm, preferably 20~100mm.The total of rectification channel cuts Area is 0.2 ~ 0.9 times of riser cross-sectional area, preferably the 0.3 ~ 0.6 of riser cross-sectional area times.

In the demister, the ends side wall II in rectification channel can flush or extend into riser with riser inner wall Internal certain distance m, m are 0.1 ~ 0.9 times, preferably 0.3 ~ 0.6 times of length l.The ends side wall II when rectification channel and liter When inner surface of trachea flushes, rectification the bottom of the channel end is also flushed with riser inner wall;When the side wall II in rectification channel extend into liter When pipe certain distance m, rectification the bottom of the channel end is flushed with side wall end.

In the demister, it is 20~200mm that there are certain distance A, distance A in rectification the bottom of the channel apart from tower tray, preferably For 40~80mm.

In the demister, riser lower end is concordant with tower tray or is less than tower tray a distance, the two airtight connection;It rises The diameter of tracheae and the percent opening of tower tray can be given really according to actual operating mode or design requirement by those skilled in the art It is fixed.

In the demister, rectification channel, capping plate and riser can weld together or global formation.

In the demister, outer barrel is preferably cylinder, and outer barrel diameter D is 1.5-6 times of draft tube diameter d, preferably 2-3 times.Upper edge the certain distance P, distance P that the upper edge of outer barrel is higher by riser are 1~8 times of rectification channel height h, preferably 2~5 times.The lower edge of outer barrel has a certain distance B apart from tower tray, and less than the lower edge in rectification channel, outer barrel lower edge away from tower tray away from It is 5~100mm, preferably 20~50mm from B.The overall height H of outer barrel is 2.5~10 times of rectification channel height, preferably 3~ 5 times.The shape of outer barrel can also be the combination of one or more of cone cylinder, inversed conical drum or reducing cylinder etc..

In the demister, the inner surface setting groove and/or protrusion of outer barrel.Protrusion or the axis of groove and outer barrel are flat Row, or can form an angle with axis.The section of the groove or protrusion can also be rectangle, triangle or circle etc. Suitable shape.

In the demister, the inner surface of the outer barrel is preferably provided with the groove of cross sectional shape as shown in FIG. 6, should The section of groove is made of a circular arc and straight line section;The intersection point of wherein circular arc and outer tube inner surface circumference does circular arc respectively With the tangent line of circumference, the angle between tangent line is α, and α is 5 ° ~ 70 °, preferably 10 ° ~ 40 °;It is done at circular arc and straightway intersection point The tangent line of circular arc and the angle of straightway be β, β is 30 ° ~ 110 °, preferably 45 ° ~ 90 °.The depth Z of groove, i.e. circular arc with The shortest distance on straightway intersection point to outer tube inner surface circumference is 0.1 ~ 0.7 times, preferably 0.3 ~ 0.5 times of outer barrel wall thickness; Arc length X between the intersection point and straightway and the intersection point of outer tube inner surface circumference of circular arc and outer tube inner surface circumference is outer tube inner surface The 1/80 ~ 1/6 of circumference.

The junction of each component of the demister ensures sealing, does not generate gas leak phenomenon.

The demister, when work, the gas of entrained drip enters riser, Vapor Entrainment liquid from tower tray lower space Mutually rising, gas phase flow direction changes after encountering capping plate, i.e., is changed to horizontal or level of approximation direction by ascent direction, and Part droplet is attached to since effect of inertia and capping plate collide on capping plate, and the drop of attachment becomes larger, when Drop arrive greatly its own generation gravity be more than gas climbing power and surface tension of liquid resultant force when, drop just from cover plate It is separated on surface, completes first time gas-liquid separation;The gas of entrained drip enters along horizontal or level of approximation direction Rectification channel, since there is certain length in rectification channel, and rectification channel total sectional area is less than riser cross-sectional area, originally speed The gas for spending the more dispersed entrained drip in direction, after entering rectification channel, directional velocity is changed to the side along rectification channel To, directional velocity comparison rule and concentration, and since circulation area reduces, it is fast after so that the gas of entrained drip is entered rectification channel Degree increases.When the directional velocity of the gas of entrained drip changes, partial drop collides with rectification vias inner walls, and is attached to It in rectification vias inner walls, and then is constantly flowed through the gas blowout rectification channel in rectification channel and is fallen, complete second of gas-liquid Separation.Meanwhile in rectification channel, since the gas velocity direction of entrained drip changes, part droplet is in inertia force effect Lower generation mutually collision, droplet aggregation becomes big drop, and speed increases when the gas stream rectified channel of entrained drip, adds The acute movement of drop, improves the probability that droplet mutually collides, and so that droplet is easier to assemble and is become big drop, and with gas Body is together with larger speed outflow rectification channel.The gas of the entrained drip flowed out from rectification channel has larger speed, Directional velocity compares concentration, and the drop carried secretly is bigger, and continuation collides with outer tube inner wall, changes the flowing of gas again Direction, the i.e. gas of entrained drip along rectification channel direction by being changed to flow along the circumferencial direction of outer tube inner wall.Due to folder Guttiferous gas velocity is larger, and is flowed up along reeded outer tube inner wall rotation is opened up, therefore will produce brighter Aobvious shaving effect.The shaving effect, when referring to that the high-speed gas of entrained drip is flowed up along outer tube inner wall rotation, liquid It drops under the action of inertia force and is constantly thrown toward outer, drop enters groove and the arc section in groove moves, due to angle α It is 5 ° ~ 70 °, the arc surface that drop continues on groove can be made to do and smoothly move, contact aggregation becomes larger between drop, until meeting It is hindered to straightway, assemble the drop to become larger and hit strongly with straightway wall surface, and is attached to the straight of outer tube inner wall groove On line segment, drop continues to assemble and become larger, and then goes downstream along outer tube inner wall;And gas then continues to keep high speed along outer barrel Wall rotation flows up, and realizes gas-liquid separation for the third time, and reduce entrainment.By above-mentioned rectification, accelerates and scrape Face effect makes fluid realize the separation of drop and gas in flow process.

The mist eliminating zone is preferably connected by cone-shaped reducing with flue gas emission area, the mist eliminating zone and flue gas emission The tower diameter ratio in area is 1.2 ~ 5.

The flue gas emission area is generally the chimney structure in conventional flue gas wet desulphurization process, the chimney bottom Portion is connected with mist eliminating zone tower body, is preferably connected with mist eliminating zone tower body by cone-shaped reducing, and exhanst gas outlet is arranged in chimney top;It is excellent It is selected in chimney top setting outer sleeve, the outer sleeve is the tubular structure of upper and lower opening, can be cylindric or cone cylinder shape, Outer sleeve upper edge is higher by chimney top certain distance, generally 0.2~10m, preferably 0.5~5m, and the lower edge of outer sleeve is less than The upper edge of chimney, preferably shorter than 0.5 ~ 5m of chimney upper edge;It is annular space between the outer sleeve and chimney, preferably bottom is opened 1.01~1.2 times of a diameter of chimney top opening diameter of mouth.The flue gas enters outer sleeve from chimney top, from outer sleeve Top is discharged, and the gas velocity of flue gas is higher, can generate negative pressure between chimney and outer sleeve when flowing through outer sleeve, air is in negative pressure Suction under flow through between chimney and outer sleeve annular space enter outer sleeve top, air is in outer sleeve and flue gas Together from outer sleeve top discharge after mixing, flue gas has just been sufficiently mixed with air before leaving outer sleeve top discharge, greatly Width reduces " white cigarette " production quantity.

A kind of FGD dust collection method is provided while of the invention, the process employs above-mentioned flue gas desulfurization and dedustings Tower.

The FGD dust collection method of the present invention, including following content:Flue gas enters flue gas from the top of pretreatment unit Desulfurized dust collection column, contacted with the loop slurry of chilling spraying zone carry out chilling cooling and remove the part dust carried in flue gas and Sulfur dioxide enters level-one spraying zone across the flue gas of chilling spraying zone, after level-one spraying zone is mixed with loop slurry together By venturi grid scrubbing section, the components such as dust and sulfur dioxide in flue gas are absorbed by loop slurry, and flue-gas temperature reduces To 50 ~ 70 DEG C;Loop slurry completes gas-liquid separation with flue gas, and loop slurry enters bottom of tower and holds liquid bath area, and flue gas holds liquid through middle part The riser of slot enters two level spraying zone, depth dust-removal and desulfurizing is carried out with the circulation fluid counter current contacting of two level spraying zone, by two The riser that the flue gas of grade spraying zone holds liquid bath by top enters three-level spraying zone, in three-level spraying zone and the cycle after atomization Coolant liquid counter current contacting, flue-gas temperature are reduced to 30 ~ 55 DEG C, and preferable temperature is 40 ~ 53 DEG C, removes in flue gas and carries through mist eliminating zone Small water droplet, enter after outer sleeve and air are sufficiently mixed at the top of flue gas emission area from the chimney top in flue gas emission area and arrange It puts.

In the method for the present invention, the flue gas is fire coal boiler fume, coal-fired plant flue gas, catalytic cracking catalyst regeneration Flue gas, Furnace flue gas, coking flue gas or steel sintering flue gas etc..SO in flue gas₂A concentration of 50 ~ 5000mg/Nm³, preferably 200~2000 mg/Nm³, dust concentration is 30 ~ 600mg/Nm³, preferably 100 ~ 400 mg/Nm³。

In the method for the present invention, the operating condition of the fuel gas desulfurization gas wash tower is:Operation temperature is 60 ~ 300 DEG C, operation Pressure is 0.1 ~ 500kPa, and treatment quantity is 1000 ~ 1000000Nm³/h。

In the method for the present invention, the chilling spraying zone, level-one spraying zone, the liquid-gas ratio in two level spraying zone be all 2 ~ 50L/Nm³, preferably 5 ~ 25L/Nm³;The liquid-gas ratio of the three-level spraying zone is 0.5 ~ 15 L/Nm³, preferably 1.5 ~ 7.5L/ Nm³。

In the method for the present invention, it is molten that the alkaline solution is selected from sodium hydroxide solution, calcium hydroxide solution, magnesium hydroxide One kind or several in liquid, sodium carbonate liquor, sodium sulfite solution, sodium citrate solution, lime stone slurry, ammonium hydroxide or seawater etc. Kind.

In the method for the present invention, the loop slurry holds liquid bath area from bottom of tower, after the pressurization of bottom of tower circulating pump, a part Chilling cooling is carried out to flue gas into chilling spraying zone, another part enters level-one spraying zone and is dusted desulfurization to flue gas, It is remaining to be delivered to subsequent cell through comb line outside loop slurry and handled;

In the method for the present invention, the liquid level of loop slurry in liquid bath area is held by the adjusting on fresh water pipeline I in the bottom of tower Valve is controlled.

In the method for the present invention, the pH value control of the loop slurry in liquid bath area is held 6 ~ 11 in the bottom of tower, preferable ph Control range is that 7 ~ 8, pH on-line detectors are located on the pump entry pipeline of bottom of tower, by adjusting on alkaline solution line I Regulating valve carrys out the pH value of control loop slurries.

In the method for the present invention, the bottom of tower loop slurry effluent stream amount is according to the concentration of suspension in the loop slurry of bottom of tower It is adjusted, the concentration of suspension control in the loop slurry of bottom of tower is 0.1 ~ 1.5g/L, and preferred concentration is 0.2 ~ 1.0g/L, is suspended Object concentration measuring apparatus is located on the pump entry pipeline of bottom of tower, by adjusting loop slurry effluent stream amount come control loop slurries Concentration of suspension.

In the method for the present invention, the circulation fluid in liquid bath is held at the middle part, and entering two level after the pressurization of middle part circulating pump sprays Area is drenched, is atomized and contacts with flue gas adverse current to the dedusting of flue gas progress depth, desulfurization through atomizer.

In the method for the present invention, the pH value control of the circulation fluid in liquid bath area is held 6 ~ 8 in the middle part, the control of preferable ph Ranging from 6.5 ~ 7.5, pH on-line detectors are located on the pump entry pipeline of middle part, by adjusting on alkaline solution line II Regulating valve come control middle part circulation fluid pH value.

In the method for the present invention, the circulating cooling liquid in liquid bath is held on the top, the part after coolant recirculation pump pressurizes Outer row, remaining circulating cooling liquid enter cooler and are cooled to 0 ~ 40 DEG C, and preferable temperature is 10 ~ 20 DEG C, and circulating cooling liquid enters three Grade spraying zone contacts with flue gas adverse current through atomizer atomization and carries out cooling and depth dedusting, desulfurization to flue gas.

In the method for the present invention, the top is held liquid bath area liquid level and is controlled by the regulating valve on fresh water pipeline II System.The pH value control of liquid bath area is held 6 ~ 8 in the top, and the control range of preferable ph is 6.5 ~ 7.5, pH on-line detectors position In on coolant recirculation pump suction line, by adjusting the regulating valve on alkaline solution line III come control loop coolant liquid PH value.

Compared with the prior art, the advantages of the present invention are as follows:

1, the present invention uses heavy caliber atomizer, two circles of ejection of the opposite atomizer of split shed in chilling spraying zone Taper surface hits mutually the plane for being formed and covering entire tower diameter, which to flue gas comprehensively effectively intercept, and realizes flue gas Chilling cooling, and remove the dust and sulfur dioxide carried in flue gas, further mitigate the burden in follow-up work area, significantly Improve dedusting, the desulfuration efficiency of flue gas..

2, demister of the invention effectively removes the smaller drop of the grain size carried secretly in gas, and demisting efficiency is high;Gas stream Dynamic uniform, flow resistance is small, and pressure drop is low;It is simple in structure, it is easy to make, it is not easy to plug and fouling, without backwash;Water-saving result Good, the moisture removed from the gas of entrained drip can reduce water consumption with recycling.

3, liquid bath is held in present invention setting three, carries out three-level spray washing to flue gas, while holding liquid bath using cold on top But liquid washs, and reduces flue-gas temperature, and entrained saturation vapour content is greatly reduced in flue gas, thus is analysed after flue gas emission The water mist amount gone out is greatly reduced, and eliminates " white cigarette long queue " phenomenon of wet desulphurization, and " white cigarette " phenomenon of flue gas emission mouth is notable It reduces.

4, reverse taper deformation diameter is arranged in the present invention between mist eliminating zone and three-level spraying zone, advantageously reduces mist eliminating zone gas Speed strengthens flue gas defogging effect;Cone-shaped reducing is arranged with mist eliminating zone in flue gas emission area, is conducive to the flow velocity for improving flue gas, cigarette The gas velocity of gas is bigger, and it is higher that flue gas leaves the rising height behind flue gas emission area, is more conducive to the diffusion of flue gas, thus plume is got over It is short.

5, fuel gas desulfurization gas wash tower flue gas emission area of the invention is using the structure of " chimney+outer sleeve ", and flue gas is by removing Negative pressure is generated after the acceleration of fog-zone and cone-shaped reducing, when flowing through outer sleeve to suck outside air, flue gas is with air in housing From outer sleeve top discharge after being sufficiently mixed in cylinder, " white cigarette " production quantity is significantly reduced.

6, fuel gas desulfurization gas wash tower Wei " Jiu shapes of the invention " structure, flue gas ash removal, desulfurization and depth are realized in a tower The triple functions of demisting are spent, each functional area coordinated mutually promotes, significantly reduces the floor space of equipment, significantly subtract The expense needed for plant construction, transformation is lacked.

Description of the drawings

Fig. 1 is fuel gas desulfurization gas wash tower structural schematic diagram of the present invention.

Fig. 2 is present invention process flow diagram.

Fig. 3 is the demister structural schematic diagram of fuel gas desulfurization gas wash tower of the present invention.

Fig. 4 is a kind of rectification channel and the schematic cross-section with groove outer barrel in the demister of the present invention.

Fig. 5 is another rectification channel and the schematic cross-section with raised outer barrel in the demister of the present invention.

Fig. 6 is that the demister middle section of the present invention is the groove schematic diagram that circular arc and straightway are constituted.

In figure:1- pretreatment units;2- holds bottom of tower liquid bath area;3- advanced treatment units;4- chilling spraying zones;5- level-ones are sprayed Drench area;6- venturi grid scrubbing sections;Liquid bath area is held in the middle part of 7-;8- two level spraying zones;9- holds on top liquid bath area;10- three-levels are sprayed Drench area;11- reverse taper deformation diameters;12- mist eliminating zones;13- cone-shaped reducings;14- flue gas emissions area;15- heavy caliber atomizers; 16- spray pipes I;17- spray pipes II;18- atomizers;19- venturi grids;Liquid bath is held in the middle part of 20-;21- overflow pipes I;22- riseies I;23- spray pipes III;24- holds liquid bath in top;25- overflow pipes II;26- riseies II;27- spray pipes IV;28- demisters;29- coolers;30- coolant recirculation pumps;Circulating pump in the middle part of 31-;The bottoms of tower 32- circulating pump;33- chimneys; 34- outer sleeves;

Wherein, 1-1- flue gases pipeline;2-1 liquid level gauges I;The bottoms of tower 2-2 overflow line;The bottoms of tower 2-3 slurries extract pipeline out;2-4 alkalinity Solution pipeline I;2-5 loop slurry Trunk Lines;The outer comb line of 2-6 loop slurries;4-1 loop slurry pipelines I;5-1 loop slurries Pipeline II;The fresh water pipeline I of 7-1;7-2 alkaline solution lines II;Circulation fluid extracts pipeline out in the middle part of 7-3;Liquid pipe is recycled in the middle part of 8-1 Line;The fresh water pipeline II of 9-1;9-2 alkaline solution lines III;9-3 liquid level gauges II;The tops 9-4 circulating cooling liquid extracts pipeline out; The outer comb line of the tops 9-5 circulating cooling liquid;The tops 10-1 circulating cooling liquid pipeline;28-1- mist eliminating zone tower trays;28-2- riseies; 28-3- rectifications channel;28-4- outer barrels;28-5- covers plate;28-6- grooves;28-7- protrusions.

Specific implementation mode

Below in conjunction with drawings and examples, the present invention will be described in detail.

Liquid bath area 2 is held in the fuel gas desulfurization gas wash tower of the present invention, including pretreatment unit 1, advanced treatment unit 3 and bottom of tower, Pretreatment unit 1 is connected to advanced treatment unit 3 by flue, and three constitutes " Jiu shapes " structure;The pretreatment unit 1 is from top to bottom followed successively by chilling spraying zone 4, level-one spraying zone 5, venturi grid scrubbing section 6;The advanced treatment unit 3 Be followed successively by from the bottom to top liquid bath area 7 is held at middle part, liquid bath area 9 is held on two level spraying zone 8, top, three-level spraying zone 10, mist eliminating zone 12, Flue gas emission area 14.

The fuel gas desulfurization gas wash tower of the present invention, the pretreatment unit 1 are 0.2 ~ 1 with 3 tower diameter ratio of advanced treatment unit, It is preferably in a proportion of 0.4 ~ 1.

4 top of chilling spraying zone is connected with flue gas pipeline 1-1;If 4 axis of chilling spraying zone is set up Dry opening upwards or downward heavy caliber atomizer 15, each heavy caliber atomizer 15 are connected with spray pipe I 16, greatly The inlet attack caliber of bore atomizer 15 and the tower diameter ratio of chilling spraying zone 4 be 0.005 ~ 0.1, preferably 0.01 ~ 0.06;15 spray angles of heavy caliber atomizer are 60 ~ 150 °, and optimized angle is 120 ~ 150 °;The water mist of spray is in Solid conical, conical bottom surface diameter are more than the tower diameter of chilling spraying zone 4;Preferably at least include that a pair of openings is opposite(One Open Side Down, another opening upwards)Heavy caliber atomizer 15, more preferably 2 ~ 3 pairs;The opposite heavy caliber of each pair of opening Two conical surfaces that atomizer 15 sprays out hit mutually the plane for being formed and covering entire tower diameter, which carries out flue gas It is comprehensive effectively to intercept, realize the chilling cooling of flue gas, and remove the dust and sulfur dioxide carried in flue gas.Every spray tube Line I 16 can connect the 2 heavy caliber atomizers 15 of 1 heavy caliber atomizer 15 or opening direction on the contrary;Described is big The inlet attack caliber of bore atomizer 15 generally can be DN50 ~ 200.

One or more layers spray pipe II 17 is arranged in the level-one spraying zone 5, when Multi-layer sprinkling pipeline II 17 is set, The distance between spray pipe II 17 is 0.5 ~ 5m, and preferred distance is 1 ~ 2.5m;The connections of spray pipe II 17 cycle It is provided with multiple atomizers 18 on slurry line II 5-1, spray pipe II 17;The level-one spraying zone 5 will be for that will follow Ring slurry spraying, the droplet after atomization and flue gas current contacting, remove the dust and sulfur dioxide carried in flue gas.

The venturi grid scrubbing section 6 is provided with one or more layers venturi grid 19, using multilayer venturi lattice Two layers neighbouring of venturi grid 19 is staggered when grid 19;The venturi grid 19 is enhancing loop slurry pair Dust and SO₂Washing effect, increase to dust and SO₂Removal efficiency.

It holds liquid bath area 2 and is separately connected alkaline solution line I 2-4, bottom of tower overflow line close to tower wall side in the bottom of tower 2-2 and liquid level gauge I 2-1;Flow control valve is set on the alkaline solution line I 2-4, for being filled into bottom of tower slurries Alkaline solution adjusts its pH value;The bottom of tower overflow line 2-2 is used for automatic when the liquid level of bottom of tower slurries is more than setting value Bottom of tower slurries are discharged, bottom of tower slurry plugs flue is avoided;Hold 2 bottom of liquid bath area connection bottom of tower slurries extraction in the bottom of tower Pipeline 2-3, bottom of tower slurries extraction pipeline 2-3 are connected with bottom of tower circulating pump 32, realize bottom of tower slurries in chilling spraying zone 4 and one The circulated sprinkling of grade spraying zone 5.

The middle part holds liquid bath area 7 and several riser I22 is arranged, and the flue gas from pretreatment unit 1 is through flue Into advanced treatment unit 2, two level spraying zone 8 is entered by riser I 22;The middle part hold liquid bath area 7 be arranged one or 21 height of multiple overflow pipe I 21, overflow pipe I holds the circulation fluid in liquid bath 20 by overflowing less than 22 height of riser I, middle part Flow tube I 21 holds liquid bath area 2 into bottom of tower;The middle part holds 20 bottom of liquid bath and is connected with middle part circulation fluid extraction pipeline 7-3, Middle part circulation fluid extraction pipeline 7-3 is connected with middle part circulating pump 31, and the cycle for realizing middle part circulation fluid in two level spraying zone 8 is sprayed Leaching.

It holds liquid bath area 7 and is connected with fresh water pipeline I 7-1 and alkaline solution line II close to tower wall side in the middle part 7-2;Flow control valve is set on the fresh water pipeline I 7-1, the Signal Regulation fed back according to bottom of tower liquid level gauge I 2-1 is new The flow of fresh water is used for the liquid level in control tower Di Chi liquid baths area 2;It is provided with flow tune on the alkaline solution line II 7-2 Valve is saved, the Signal Regulation for extracting the pH meter feedback being arranged on pipeline 7-3 out according to middle part circulation fluid holds what liquid bath area 7 filled to middle part The flow of alkaline solution.

One or more layers spray pipe III 23, setting Multi-layer sprinkling pipeline III 23 is arranged in the two level spraying zone 8 When, the distance between spray pipe III 23 is 0.5 ~ 5m, and preferred distance is 1 ~ 2.5m;The connections of spray pipe III 23 Middle part circulation fluid pipeline is provided with multiple atomizers 18 on spray pipe III 23;The two level spraying zone 8 will be for that will follow Ring liquid mist, the droplet after atomization are contacted with flue gas adverse current, to carrying out depth dedusting and desulfurization in flue gas.

The top holds liquid bath area 9 and several riser II26 is arranged, and flue gas enters three-level by riser II 26 and sprays Area 10;The top holds liquid bath area 9 and one or more overflow pipe II 25 is arranged, and 25 height of overflow pipe II is less than riser II The circulation fluid in liquid bath 24 is held by overflow pipe II 25 into two level spraying zone 8 in 26 height, top;Hold liquid bath 24 in the top Bottom is connected with top circulating cooling liquid extraction pipeline 9-4, and top circulating cooling liquid extracts pipeline 9-4 connection coolant recirculation pumps out 30, realize circulating cooling liquid three-level spraying zone 10 circulated sprinkling.

It holds liquid bath area 9 and is connected with fresh water pipeline II 9-1 and alkaline solution line close to tower wall side in the top III 9-2;Flow control valve is set on the fresh water pipeline II 9-1, according to the Signal Regulation of liquid level gauge II 9-3 feedbacks The flow of fresh water holds the liquid level of liquid bath 24 for controlling top;It is provided with flow on the alkaline solution line III 9-2 Regulating valve, the Signal Regulation for extracting the pH meter feedback being arranged on pipeline 9-4 out according to top circulating cooling liquid hold liquid bath area 9 to top The flow of the alkaline solution of filling.

One or more layers spray pipe IV 27, setting Multi-layer sprinkling pipeline IV 27 is arranged in the three-level spraying zone 10 When, the distance between spray pipe IV 27 is 0.5 ~ 5m, and preferred distance is 1 ~ 2.5m;In the connections of spray pipe IV 27 It is provided with multiple atomizers 18 on portion circulating cooling liquid pipeline 10-1, spray pipe IV 27;The three-level spraying zone 10 is used It is atomized in the circulating cooling liquid that will hold liquid bath 24 from top, the circulating cooling liquid drop after atomization is contacted with flue gas adverse current, right Cooling down and depth dedusting, desulfurization are carried out in flue gas.

The three-level spraying zone 10 is preferably connected by reverse taper deformation diameter 11 with mist eliminating zone 12, the mist eliminating zone 12 Tower diameter ratio with three-level spraying zone 10 is 1.2 ~ 3.

The mist eliminating zone 12 is provided with demister 28, and demister 28 includes several demisting components arranged side by side, is each removed Mist component includes riser 28-2 and outer barrel 28-4, and outer barrel 28-4 is arranged in the outside of riser 28-2, preferably with riser 28-2 is on the same axis;Riser 28-2 is fixed on 12 tower tray 28-1 of mist eliminating zone, the top setting capping of riser 28-2 Plate 28-5;Several rectification channel 28-3 are uniformly arranged on the circumference of riser 28-2, rectification channel 28-3 is outside riser 28-2 The tangential direction level of wall is embedded in, and side wall Is and riser 28-2 tube wall of the rectification channel 28-3 close to the sides outer barrel 28-4 are tangent, Another side wall II intersects with riser 28-2 tube walls, and each rectification channel direction of rotation 28-3 is identical;At the top of the 28-3 of rectification channel with Capping plate 28-5 is flushed, and bottom is intersected with riser 28-2 tube walls.

In the demister 28, rectification channel 28-3 generally settings 1 ~ 12, preferably 4-8.Rectification channel 28-3's Wall thickness is preferably identical as the wall thickness of riser 28-2.

In the demister 28, the length l of rectification channel 28-3 is the length of side wall II, and width w is rectification channel 28- Maximum horizontal range between 3 two sides, height h are the maximum normal distance between the top and bottom rectification channel 28-3;It is wherein long Spend 2 ~ 5 times, preferably 3 ~ 4 times that l is width w;The cross sectional shape of rectification channel 28-3 be rectangle, ellipse, circle, it is trapezoidal or The combination of one or more of semicircle etc., one or more of preferably rectangular, oval or round combination.Rectification channel The size of 28-3 determined according to actual operating mode or design requirement by those skilled in the art, such as the rectification channel 28- 3 height h is generally 20~600mm, preferably 100~300mm;The width w of rectification channel 28-3 is generally 10~200mm, Preferably 20~100mm.The total sectional area of rectification channel 28-3 is 0.2 ~ 0.9 times of riser 28-2 cross-sectional areas, preferably 0.3 ~ 0.6 times of riser 28-2 cross-sectional areas.

In the demister 28, the ends side wall II of the rectification channel 28-3 can be neat with riser 28-2 inner walls Certain distance m inside riser 28-2 is put down or extend into, m is 0.1 ~ 0.9 times, preferably 0.3 ~ 0.6 times of length l.Work as rectification When the ends side wall II of channel 28-3 are flushed with riser 28-2 inner walls, rectification channel 28-3 bottom ends also with riser 28-2 Inner wall flushes;When the side wall II of rectification channel 28-3 extend into riser 28-2 inside certain distance m, the rectification channel bottoms 28-3 Portion end is flushed with side wall end.

In the demister 28, rectification channel 28-3 distance from bottom tower trays 28-1 has a certain distance A, and distance A is 20~ 200mm, preferably 40~80mm.

In the demister 28, the lower ends riser 28-2 are concordant with tower tray 28-1 or are less than tower tray 28-1 a distances, The two airtight connection;The diameter of riser 28-2 and the percent opening of tower tray 28-1 can according to actual operating mode or design requirement, It is determined by those skilled in the art.

In the demister 28, the rectification channel 28-3, capping plate 28-5 and riser 28-2 can be welded on Together or global formation.

In the demister 28, the outer barrel 28-4 is preferably cylinder, and outer barrel 28-4 diameters D is that riser 28-2 is straight 1.5-6 times of diameter d, preferably 2-3 times.Upper edge the certain distance P, distance P that the upper edge of outer barrel 28-4 is higher by riser 28-2 be 1~8 times of rectification channel 28-3 height h, preferably 2~5 times.The lower edge of outer barrel 28-4 has certain distance B apart from tower tray 28-1, And less than rectification channel 28-3 lower edge, distance B of the outer barrel 28-4 lower edges away from tower tray 28-1 be 5~100mm, preferably 20~ 50mm.The overall height H of outer barrel 28-4 is 2.5~10 times, preferably 3~5 times of rectification channel 28-3 height.The shape of outer barrel 28-4 Shape can also be the combination of one or more of cone cylinder, inversed conical drum or reducing cylinder etc..

In the demister 28, groove 28-6 and/or protrusion 28-7 is arranged in the inner surface of the outer barrel 28-4.Protrusion 28-7 or groove 28-6 are parallel with the axis of outer barrel 28-4, or can form an angle with axis.The groove 28-6 or The section of raised 28-7 can also be the suitable shapes such as rectangle, triangle or circle.

In the demister 28, the inner surface of the outer barrel 28-4 is preferably provided with cross sectional shape as shown in FIG. 6 The section of groove 28-6, groove 28-6 are made of a circular arc and straight line section;Wherein circular arc and outer barrel 28-4 inner surfaces The intersection point of circumference does the tangent line of circular arc and circumference respectively, and the angle between tangent line is α, and α is 5 ° ~ 70 °, preferably 10 ° ~ 40 °;Circle The tangent line of circular arc and the angle of straightway done at arc and straightway intersection point is β, and β is 30 ° ~ 110 °, preferably 45 ° ~ 90 °. The depth Z of groove 28-6, i.e. circular arc are outer barrel 28-4 with the shortest distance on straightway intersection point to outer barrel 28-4 inner surface circumference 0.1 ~ 0.7 times of wall thickness, preferably 0.3 ~ 0.5 times;The intersection point and straightway and outer barrel of circular arc and outer barrel 28-4 inner surface circumference Arc length X between the intersection point of 28-4 inner surface circumference is the 1/80 ~ 1/6 of outer barrel 28-4 inner surface circumference.

The junction of 28 each component of demister ensures sealing, does not generate gas leak phenomenon.

The demister 28, when work, the gas of entrained drip enters riser 28-2 from tower tray 28-1 lower spaces, Vapor Entrainment liquid phase rises, and gas phase flow direction changes after encountering capping plate 28-5, i.e., by ascent direction be changed to it is horizontal or Level of approximation direction, and part droplet is since effect of inertia collides with capping plate 28-5, and it is attached to capping plate 28-5 On, the drop of attachment becomes larger, when the gravity that drop arrives greatly its own generation is more than the climbing power and liquid surface of gas When the resultant force of power, drop is just separated from the surfaces capping plate 28-5, and first time gas-liquid separation is completed;Entrained drip Gas enters rectification channel 28-3 along horizontal or level of approximation direction, since rectification channel 28-3 has certain length, and rectification Channel 28-3 total sectional areas be less than riser 28-2 cross-sectional areas, the gas of the more dispersed entrained drip of script directional velocity, After entering rectification channel 28-3, directional velocity is changed to the direction along rectification channel 28-3, directional velocity comparison rule sum aggregate In, and since circulation area reduces, speed increases after so that the gas of entrained drip is entered rectification channel 28-3.The gas of entrained drip When the directional velocity of body changes, partial drop collides with rectification channel 28-3 inner walls, and is attached in the 28-3 of rectification channel It on wall, and then is constantly flowed through the gas blowout rectification channel 28-3 of rectification channel 28-3 and is fallen, complete second of gas-liquid point From.Meanwhile in the 28-3 of rectification channel, since the gas velocity direction of entrained drip changes, part droplet is in inertia masterpiece With lower generation mutually collision, droplet aggregation becomes big drop, and speed when the gas stream rectified channel 28-3 of entrained drip Increase, exacerbate the movement of drop, improve the probability that droplet mutually collides, droplet is made to be easier to assemble as big liquid Drop, and with gas with larger speed outflow rectification channel 28-3.The gas of the entrained drip flowed out from rectification channel 28-3 Body has larger speed, and directional velocity compares concentration, and the drop carried secretly is bigger, and continuation is touched with outer barrel 28-4 inner walls It hits, changes the flow direction of gas again, i.e., the gas of entrained drip along the rectification channel directions 28-3 by being changed to along outer barrel The circumferencial direction of 28-4 inner walls flows.Since the gas velocity of entrained drip is larger, and along the outer barrel for opening up fluted 28-6 The rotation of 28-4 inner walls flows up, therefore will produce obvious shaving effect.The shaving effect, refers to entrained drip High-speed gas along outer barrel 28-4 inner walls rotation flow up when, drop is constantly thrown toward outer, liquid under the action of inertia force Drop enters groove 28-6 and the arc section in groove 28-6 moves, and since angle α is 5 ° ~ 70 °, drop can be made to continue on The arc surface of groove 28-6, which is done, smoothly to be moved, and aggregation is contacted between drop and is become larger, until encountering, straightway is hindered, and aggregation becomes Big drop is hit strongly with straightway wall surface, and is attached on the straightway of outer barrel 28-4 inboard wall grooves 28-6, and drop continues Assemble and become larger, and then goes downstream along outer barrel 28-4 inner walls;And gas then continues that high speed is kept to rotate along outer barrel 28-4 inner walls It flows up, realizes gas-liquid separation for the third time, and reduce entrainment.By above-mentioned rectification, acceleration and shaving effect, Fluid is set to realize the separation of drop and gas in flow process.

The mist eliminating zone 12 is preferably connected by cone-shaped reducing 13 with flue gas emission area 14, the mist eliminating zone 12 with The tower diameter ratio in flue gas emission area 14 is 1.2 ~ 5.

The flue gas emission area 14 is generally 33 structure of chimney in conventional flue gas wet desulphurization process, the cigarette 33 bottom of chimney is connected with 12 tower body of mist eliminating zone, is preferably connected with 12 tower body of mist eliminating zone by cone-shaped reducing 13,33 top of chimney Exhanst gas outlet is set;It is preferred that outer sleeve 34 is arranged at 33 top of chimney, the outer sleeve 34 is the tubular structure of upper and lower opening, Can be cylindric or cone cylinder shape, 34 upper edge of outer sleeve be higher by 33 top certain distance of chimney, generally 0.2~10m, preferably 0.5~5m, the lower edge of outer sleeve 34 are less than the upper edge of chimney 33, preferably shorter than 33 0.5 ~ 5m of upper edge of chimney;The outer sleeve 34 bottom opening diameters are more than 33 open top diameter of chimney, preferably 1.01~1.2 times of 33 open top diameter of chimney;Institute The flue gas stated enters outer sleeve 34 from 33 top of chimney, and from 34 top discharge of outer sleeve, the gas velocity of flue gas is higher, is flowing through housing Negative pressure can be generated between chimney 33 and outer sleeve 34 when cylinder 34, air flows through chimney 33 and housing under the suction of negative pressure Annular space between cylinder 34 enters 34 top of outer sleeve, air mixed with flue gas in outer sleeve 34 after together from outer sleeve 34 Top discharge, flue gas have just been sufficiently mixed with air before leaving 34 top discharge of outer sleeve, and it is raw to significantly reduce " white cigarette " Cheng Liang.

Embodiment

Liquid bath area 2 is held in a kind of fuel gas desulfurization gas wash tower, including pretreatment unit 1, advanced treatment unit 3 and bottom of tower, pre- to locate Reason unit 1 is connected to advanced treatment unit 3 by flue, and three constitutes " Jiu shapes " structure.Pretreatment unit 1 is from top to bottom It is followed successively by chilling spraying zone 4, level-one spraying zone 5, venturi grid scrubbing section 6;During advanced treatment unit 3 is followed successively by from the bottom to top Liquid bath area 9, three-level spraying zone 10, mist eliminating zone 12, flue gas emission area 14 are held in Bu Chi liquid baths area 7, two level spraying zone 8, top.

4 top of chilling spraying zone is connected with flue gas pipeline 1-1, and two layers of spray pipe I 16, spray is arranged in chilling spraying zone 4 The distance between pipeline I 16 be 2m, spray pipe I 16 setting there are one vertically upward with a heavy caliber mist vertically downward Change nozzle 15, the inlet attack caliber of heavy caliber atomizer 15 is DN80, and spray angles are 150 °.

Two layers of spray pipe II 17 is arranged in level-one spraying zone 5, and the distance between spray pipe II 17 is 2m, spray pipe 17 loop slurry pipeline II 5-1 connections of II are provided with several atomizers 18 on spray pipe II 17.Venturi grid Scrubbing section 6 is provided with two layers of venturi grid 19, and two layers of venturi grid 19 is staggered.

Bottom of tower hold liquid bath area 2 close to tower wall side be separately connected alkaline solution line I 2-4, bottom of tower overflow line 2-2 and Flow control valve is set on liquid level gauge I 2-1, alkaline solution line I 2-4, and bottom of tower is held 2 bottom of liquid bath area connection bottom of tower slurries and taken out Go out pipeline 2-3.

Middle part holds liquid bath area 7 and several riser I 22 and two overflow pipe I 21 is arranged, and 21 height of overflow pipe I is less than liter 22 height of tracheae I, middle part hold 20 bottom of liquid bath and are connected with middle part circulation fluid extraction pipeline 7-3;Liquid bath area 7 is held close to tower in middle part Wall side is connected with fresh water pipeline I 7-1 and alkaline solution line II 7-2, fresh water pipeline I 7-1, alkaline solution line Distribution setting flow control valve on II 7-2.

Two layers of spray pipe III 23 is arranged in two level spraying zone 8, and the distance between spray pipe III 23 is 2m, spray tube In the middle part of the connections of line III 23 multiple atomizers 18 are provided on circulation fluid pipeline 8-1, spray pipe III 23.

Top holds liquid bath area 9 and several riser II 26 and two overflow pipe II 25 is arranged, and 25 height of overflow pipe II is less than 26 height of riser II, top hold 24 bottom of liquid bath and are connected with top circulating cooling liquid extraction pipeline 9-4, and liquid bath area 9 is held on top It is connected with fresh water pipeline II 9-1 and alkaline solution line III 9-2, fresh water pipeline II 9-1, alkalinity close to tower wall side Flow control valve is set on solution pipeline III 9-2.

Two layers of spray pipe IV 27 is arranged in three-level spraying zone 10, and the distance between spray pipe IV 27 is 2m, spray tube It is provided with multiple atomizers 18 on the connections of line IV 27 top circulating cooling liquid pipeline 10-1, spray pipe IV 27.

Three-level spraying zone 10 is preferably connected by reverse taper deformation diameter 11 with mist eliminating zone 12, and setting is several such as in mist eliminating zone 12 Demister 28 shown in Fig. 3 ~ 6, mist eliminating zone 12 are preferably connected by cone-shaped reducing 13 with flue gas emission area 14.

33 structure of chimney in conventional flue gas wet desulphurization process is arranged in flue gas emission area 14, and 33 bottom of chimney passes through cone Bodily form reducing 11 is connected with 10 tower body of mist eliminating zone, outer sleeve 34 is arranged at 33 top of chimney, outer sleeve 34 is the circle of upper and lower opening Tubular structure, 34 upper edge of outer sleeve are higher by 33 top 5m of chimney, and the lower edge of outer sleeve 34 is less than 33 0.5 ~ 5m of upper edge of chimney, housing 1.01 ~ 1.2 times of the 33 open top diameter of a diameter of chimney of 34 bottom openings of cylinder.

The FGD dust collection method of the present invention, including following content:

Flue gas enters fuel gas desulfurization gas wash tower from the top of pretreatment unit 1, and progress is contacted with the loop slurry of chilling spraying zone 4 Chilling cools down and removes the part dust and sulfur dioxide that are carried in flue gas, enters level-one spray across the flue gas of chilling spraying zone Area 5, together by venturi grid scrubbing section 6 after level-one spraying zone 5 is mixed with loop slurry, dust and dioxy in flue gas Change the components such as sulphur to be absorbed by loop slurry, flue-gas temperature is reduced to 50 ~ 70 DEG C;Loop slurry completes gas-liquid separation with flue gas, follows Ring slurries enter bottom of tower and hold liquid bath area 2, and the riser 22 that flue gas holds liquid bath 7 through middle part enters two level spraying zone 8, sprayed with two level The circulation fluid counter current contacting in area 8 carries out depth dust-removal and desulfurizing, and the flue gas by two level spraying zone 8 holds the liter of liquid bath 9 by top Tracheae 26 enters three-level spraying zone 10, in three-level spraying zone 10 and the circulating cooling liquid counter current contacting after atomization, flue-gas temperature drop Down to 30 ~ 55 DEG C, preferable temperature is 40 ~ 53 DEG C, the small water droplet carried in flue gas is removed through mist eliminating zone, from flue gas emission area 14 33 top of chimney enters after outer sleeve 34 is sufficiently mixed with air discharges from the top of flue gas emission area 14..

Certain enterprise's exhaust gas volumn is 200000Nm³/ h, flue-gas temperature are 180 DEG C, pressure 5kPa, wherein SO₂It is a concentration of 1000mg/Nm³, dust concentration 200mg/Nm³, using fuel gas desulfurization gas wash tower of the present invention, pretreatment unit tower diameter is 3m, two level spraying zone tower diameter are 6.8m, and mist eliminating zone tower diameter is 8.2m, and chimney tower diameter is 3m, outer sieeve diameter 3.2m, and reaction is anxious Cold water spray area and level-one spraying zone loop slurry flow are 1000m³/ h, two level spraying zone circulating fluid flow rate are 800m³/ h, three-level Spraying zone circulating cooling flow quantity is 300m³/ h, purified flue-gas temperature are 50 DEG C, wherein SO₂A concentration of 15mg/Nm³, powder Dust content is 10mg/Nm³, moisture content 83g/m³, the white cigarette of gas vent obviously eliminates.

Claims

1. a kind of fuel gas desulfurization gas wash tower, it is characterised in that:Liquid bath is held including pretreatment unit, advanced treatment unit and bottom of tower Area, pretreatment unit are connected to advanced treatment unit by flue, and three constitutes " Jiu shapes " Double-Tower Structure;Pretreatment unit From top to bottom it is followed successively by chilling spraying zone, level-one spraying zone, venturi grid scrubbing section;Advanced treatment unit is from the bottom to top successively Liquid bath area is held for middle part, liquid bath area, three-level spraying zone, mist eliminating zone and flue gas emission area are held in two level spraying zone, top;The urgency It is connected with flue gas pipeline at the top of cold water spray area;Chilling spraying zone axis sets up several opening upwards or downward heavy caliber mist Change nozzle, each heavy caliber atomizer is connected with spray pipe I, and inlet attack caliber and the chilling of heavy caliber atomizer spray The tower diameter ratio in area is 0.005 ~ 0.1, and heavy caliber atomizer spray angles are 60 ~ 150 °;The flue gas emission area is cigarette Chimney structure, chimney bottom are connected with mist eliminating zone tower body, and exhanst gas outlet is arranged in chimney top;In chimney top, outer sleeve, institute are set The outer sleeve stated is the tubular structure of upper and lower opening, and outer sleeve upper edge is higher by chimney top certain distance, and the lower edge of outer sleeve is low It is annular space between the upper edge of chimney, the outer sleeve and chimney.

2. fuel gas desulfurization gas wash tower described in accordance with the claim 1, it is characterised in that:The pretreatment unit and advanced treating Unit tower diameter ratio is 0.2 ~ 1.

3. fuel gas desulfurization gas wash tower described in accordance with the claim 1, it is characterised in that:Outer sleeve upper edge is higher by chimney top 0.2 ~10m;The lower edge of outer sleeve is less than 0.5 ~ 5m of upper edge of chimney;The a diameter of chimney top opening of the outer sleeve bottom opening 1.01~1.2 times of diameter.

4. fuel gas desulfurization gas wash tower described in accordance with the claim 1, it is characterised in that:The big mouth that chilling spraying zone axis is set up In diameter atomizer, the opposite heavy caliber atomizer of a pair of openings is included at least.

5. fuel gas desulfurization gas wash tower described in accordance with the claim 1, it is characterised in that:The level-one spraying zone be arranged one layer or Multi-layer sprinkling pipeline II, when Multi-layer sprinkling pipeline II is arranged, the distance between spray pipe II is 0.5 ~ 5m;The spray tube It is provided with multiple atomizers on line II connection loop slurries pipeline II, spray pipe II.

6. fuel gas desulfurization gas wash tower described in accordance with the claim 1, it is characterised in that:The venturi grid scrubbing section setting There is one or more layers venturi grid;Two layers neighbouring of venturi grid is staggered when using multilayer venturi grid.

7. fuel gas desulfurization gas wash tower described in accordance with the claim 1, it is characterised in that:Liquid bath area is held close to tower wall in the bottom of tower Side is separately connected alkaline solution line I, bottom of tower overflow line and liquid level gauge I;Flow is set on the alkaline solution line I Regulating valve adjusts its pH value for filling alkaline solution into bottom of tower slurries;Hold liquid bath area bottom connection bottom of tower in the bottom of tower Slurries extract pipeline out, and slurries extraction pipeline in bottom of tower is connected with bottom of tower circulating pump.

8. fuel gas desulfurization gas wash tower described in accordance with the claim 1, it is characterised in that:It is several that the setting of liquid bath area is held at the middle part Riser I, the flue gas from pretreatment unit enter advanced treatment unit through flue, enter two level spray by riser I Drench area;The one or more overflow pipe I of liquid bath area setting are held at the middle part, and overflow pipe I height is less than riser I height, middle part It holds the circulation fluid in liquid bath bottom of tower is entered by overflow pipe I and hold liquid bath;It holds liquid bath bottom and is connected with middle part cycle in the middle part Liquid extracts pipeline out, and circulation fluid extraction pipeline in middle part is connected with middle part circulating pump.

9. fuel gas desulfurization gas wash tower described in accordance with the claim 1, it is characterised in that:Liquid bath area is held close to tower wall in the middle part Side is connected with fresh water pipeline I and alkaline solution line II;Flow control valve is set on the fresh water pipeline I, according to The flow of the Signal Regulation fresh water of bottom of tower liquid level gauge I feedbacks, is used for the liquid level in control tower Di Chi liquid baths area;The alkalinity is molten Be provided with flow control valve on liquid pipe line II, according to middle part circulation fluid extract out pipeline on be arranged pH meter feedback Signal Regulation to Hold the flow of the alkaline solution of liquid bath area filling in middle part.

10. fuel gas desulfurization gas wash tower described in accordance with the claim 1, it is characterised in that:The two level spraying zone is arranged one layer Or Multi-layer sprinkling pipeline III;When Multi-layer sprinkling pipeline III is arranged, the distance between spray pipe III is 0.5 ~ 5m;Described Circulation fluid pipeline in the middle part of spray pipe III connections is provided with multiple atomizers on spray pipe III.

11. fuel gas desulfurization gas wash tower described in accordance with the claim 1, it is characterised in that:If the setting of liquid bath area is held on the top Dry riser II, flue gas enter two level spraying zone by riser II;The one or more overflow pipe II of liquid bath area setting are held on top, Overflow pipe II height is less than riser II height, and top is held the circulating cooling liquid in liquid bath and sprayed into two level by overflow pipe II Area;Top holds liquid bath bottom and is connected with top circulating cooling liquid extraction pipeline, and top circulating cooling liquid extracts pipeline connection cooling out Liquid circulating pump.

12. fuel gas desulfurization gas wash tower described in accordance with the claim 1, it is characterised in that:Liquid bath area is held close to tower in the top Wall side is connected with fresh water pipeline II and alkaline solution line III;Flow control valve is set on the fresh water pipeline II, According to the flow of the Signal Regulation fresh water of liquid level gauge II feedbacks, the liquid level of liquid bath is held for controlling top;The alkalinity is molten It is provided with flow control valve on liquid pipe line III, extracts the signal for the pH meter feedback being arranged on pipeline out according to top circulating cooling liquid Adjust the flow that the alkaline solution that liquid bath area fills is held to top.

13. fuel gas desulfurization gas wash tower described in accordance with the claim 1, it is characterised in that:The three-level spraying zone is arranged one layer Or Multi-layer sprinkling pipeline IV;When Multi-layer sprinkling pipeline IV is arranged, the distance between spray pipe IV is 0.5 ~ 5m;The spray It is provided with multiple atomizers on pipeline IV connection loop slurries pipeline IV, spray pipe IV;The three-level spraying zone is used for By from top hold liquid bath circulating cooling liquid atomization.

14. fuel gas desulfurization gas wash tower described in accordance with the claim 1, it is characterised in that:The three-level spraying zone and mist eliminating zone It is connected by reverse taper deformation diameter, the tower diameter ratio of the mist eliminating zone and three-level spraying zone is 1.2 ~ 3.

15. fuel gas desulfurization gas wash tower described in accordance with the claim 1, it is characterised in that:The mist eliminating zone is provided with demister, Demister includes several demisting components arranged side by side, and each demisting component includes riser and outer barrel, and outer barrel is arranged in a liter gas The outside of pipe;Riser is fixed on mist eliminating zone tower tray, the top setting capping plate of riser;It is uniformly set on the circumference of riser Several rectification channels are set, rectification channel is embedded in along the tangential direction level of riser outer wall, and rectification channel is close to outer barrel side Side wall I and riser tube wall are tangent, and another side wall II intersects with riser tube wall, and each rectification channel direction of rotation is identical;Rectification Channel roof is flushed with capping plate, and bottom is intersected with riser tube wall.

16. fuel gas desulfurization gas wash tower according to claim 15, it is characterised in that:In the demister, rectification channel Length l be side wall II length, maximum horizontal ranges of the width w for the two side of rectification channel between, height h be rectification channel top Maximum normal distance between portion and bottom;Wherein length l is 2 ~ 5 times of width w;The total sectional area in rectification channel is that riser is horizontal 0.2 ~ 0.9 times of sectional area,.

17. fuel gas desulfurization gas wash tower according to claim 15, it is characterised in that:In the demister, described is outer Groove is arranged in the inner surface of cylinder, and the section of the groove is made of a circular arc and straight line section;Wherein circular arc and table in outer barrel The intersection point of face circumference does the tangent line of circular arc and circumference respectively, and the angle between tangent line is α, and α is 5 ° ~ 70 °;Circular arc is handed over straightway The tangent line of circular arc and the angle of straightway that point place is done are β, and β is 30 ° ~ 110 °;The depth Z of groove, i.e. circular arc and straightway The shortest distance on intersection point to outer tube inner surface circumference is 0.1 ~ 0.7 times of outer barrel wall thickness;Circular arc and outer tube inner surface circumference Arc length X between intersection point and straightway and the intersection point of outer tube inner surface circumference is the 1/80 ~ 1/6 of outer tube inner surface circumference.

18. fuel gas desulfurization gas wash tower described in accordance with the claim 1, it is characterised in that:The mist eliminating zone and flue gas emission area It is connected by cone-shaped reducing, the tower diameter ratio in the mist eliminating zone and flue gas emission area is 1.2 ~ 5.

19. a kind of FGD dust collection method, it is characterised in that:The process employs the flue gas desulfurizations described in claim 1 ~ 18 Gas wash tower.

20. according to the method for claim 19, it is characterised in that including following content:Flue gas is from the top of pretreatment unit Into fuel gas desulfurization gas wash tower, is contacted with the loop slurry of chilling spraying zone and carry out chilling cooling and remove the portion carried in flue gas Divide dust and sulfur dioxide, enters level-one spraying zone across the flue gas of chilling spraying zone, it is mixed in level-one spraying zone and loop slurry Together by venturi grid scrubbing section after conjunction, the components such as dust and sulfur dioxide in flue gas are absorbed by loop slurry, flue gas Temperature is reduced to 50 ~ 70 DEG C;Loop slurry completes gas-liquid separation with flue gas, and loop slurry enters bottom of tower and holds liquid bath area, flue gas warp The riser that liquid bath is held at middle part enters two level spraying zone, and it is de- to carry out depth dedusting with the circulation fluid counter current contacting of two level spraying zone Sulphur, the riser that the flue gas by two level spraying zone holds liquid bath by top enters three-level spraying zone, in three-level spraying zone and mist Circulating cooling liquid counter current contacting after change, flue-gas temperature are reduced to 30 ~ 55 DEG C, and the small water carried in flue gas is removed through mist eliminating zone Drop enters after outer sleeve is sufficiently mixed with air from the chimney top in flue gas emission area from flue gas emission area top discharge.

21. according to the method for claim 19, it is characterised in that:SO in the flue gas₂A concentration of 50 ~ 5000mg/Nm³, Dust concentration is 30 ~ 600mg/Nm³。

22. according to the method for claim 19, it is characterised in that:The operating condition of the fuel gas desulfurization gas wash tower is: Operation temperature is 60 ~ 300 DEG C, and operating pressure is 0.1 ~ 500kPa, and treatment quantity is 1000 ~ 1000000Nm³/h。

23. according to the method for claim 19, it is characterised in that:The chilling spraying zone, level-one spraying zone, two level spray The liquid-gas ratio drenched in area is all 2 ~ 50L/Nm³;The liquid-gas ratio of the three-level spraying zone is 0.5 ~ 15 L/Nm³。

24. according to the method for claim 19, it is characterised in that:The loop slurry holds liquid bath area from bottom of tower, warp After the circulating pump pressurization of bottom of tower, a part enters chilling spraying zone and carries out chilling cooling to flue gas, and another part enters level-one spray Area is dusted desulfurization to flue gas, remaining is delivered to subsequent cell through comb line outside loop slurry and is handled;The bottom of tower The liquid level for holding loop slurry in liquid bath area is controlled by the regulating valve on fresh water pipeline I;Hold liquid bath in the bottom of tower The pH value of the loop slurry in area is controlled 6 ~ 11.

25. according to the method for claim 19, it is characterised in that:The circulation fluid in liquid bath is held at the middle part, through middle part Enter two level spraying zone after circulating pump pressurization, is atomized through atomizer and is contacted with flue gas adverse current to the dedusting of flue gas progress depth, taken off Sulphur;The pH value control of the circulation fluid in liquid bath area is held 6 ~ 8 in the middle part, and the control range of preferable ph is 6.5 ~ 7.5.

26. according to the method for claim 19, it is characterised in that:The circulating cooling liquid in liquid bath is held on the top, warp Coolant recirculation pump pressurization rear portion is exceptionally arranged, remaining circulating cooling liquid enters cooler and is cooled to 0 ~ 40 DEG C, and preferable temperature is 10 ~ 20 DEG C, circulating cooling liquid enters three-level spraying zone, is contacted with flue gas adverse current through atomizer atomization and carries out cooling and depth to flue gas Spend dedusting, desulfurization;It holds liquid bath area liquid level and is controlled by the regulating valve on fresh water pipeline II in the top;Described The pH value control of liquid bath area is held 6 ~ 8 in top.