CN111692592B - Method for cooperatively treating household garbage by cement kiln - Google Patents

Abstract

The invention relates to the field of environmental protection, in particular to a method for cooperatively treating household garbage by a cement kiln; the processing steps are as follows: carrying out leaching treatment, sorting, crushing, drying, extruding granulation and incineration; according to the invention, the cheap forming auxiliary agent obtained by modifying the waste plastics is added, so that the household garbage is changed into granular cement kiln fuel which is stable in heat value, uniform in quality, stable in components and easy to burn, the characteristics of high temperature, large residual heat amount, residue utilization and the like of the cement kiln are combined, the waste is dried by fully utilizing the residual heat of the cement kiln, the burned ash residues are used as cement production raw materials, and the household garbage is changed into valuable; according to the invention, through a two-stage incineration technology, firstly, garbage granules are subjected to high-temperature thermal decomposition in a low-oxygen environment, and then decomposed solids and gases are introduced into a combustion chamber for full combustion; the invention solves the problems of poor combustion effect of domestic garbage, poor tail gas emission quality, incomplete slag combustion and the like, and can not cause secondary pollution.

Description

A method for co-processing domestic waste in a cement kiln

technical field

The invention relates to the field of environmental protection, in particular to a method for co-processing domestic garbage in a cement kiln.

Background technique

With the continuous improvement of people's living standards and the level of urbanization, more and more domestic wastes are produced by people, and there are more and more types of wastes contained in the wastes. The disposal of urban wastes has received more and more attention from the world's environmental protection organizations. .

CN109539264A discloses a garbage incineration equipment and a garbage incineration method, which relate to the field of garbage disposal, and solve the problem that the spray gun of the existing garbage incineration equipment is easy to affect the leachate atomization effect when the pressure is unstable, and the backflow of the leachate can affect the gas consumption of other users. The main point of the technical solution is that the incineration equipment includes an incinerator, a stationary rack, a collection box arranged under the stationary rack, a spray gun, a water pump arranged on the side of the collection box, a liquid inlet pipe, a main pipeline, and a gas storage. A tank and an air intake pipe, the method comprising: a. Set aside the garbage; b. The leachate is allowed to stand; c. Garbage incineration; d. Spray into the leachate; e. Flue gas premixing; f. For leachate recovery, by adding a gas storage tank between the main pipeline and the spray gun, pressure storage can be carried out through the gas storage tank, so that the leachate has a good atomization effect, and the leachate can only flow into the gas storage tank after the nozzle is blocked. , and will not flow into the main circuit and affect other users.

CN107702111A provides a device for mixing and burning sludge in a waste incineration boiler, including: a sludge bin, a feeder, a plunger pump, a pipeline and an impurity remover; the sludge bin is used for storing sludge, and the bottom of the sludge bin is used for storing sludge. The feeder is provided; the feeder transports the sludge to the plunger pump, and the plunger pump transports the sludge to the furnace of the waste incineration boiler through a pipeline; the outlet of the plunger pump An impurity remover is arranged between the inlet of the pipeline, and a filter screen is arranged inside the impurity remover, and the filter screen filters out impurities in the sludge. The invention increases the mixing of sludge in the whole process of waste incineration through the garbage incinerator, reduces the environmental pollution caused by the sludge for the society, and realizes the uniform addition of sludge in the process of sludge mixing and incineration, and does not block the pipeline and does not affect the furnace. Internal secondary air supply air to improve the stability of combustion conditions in the furnace.

CN103234205B discloses a garbage incinerator, which includes a furnace body and a grate arranged in the furnace body, and also includes a stopper for preventing garbage from falling on the grate, the stopper is provided with perforations, and the stopper A piece is arranged in the furnace body and above the grate. Through the setting of the stopper, the newly thrown garbage can be placed on the stopper, so it will not fall directly on the grate to extinguish the fire on the grate; moreover, the garbage can be placed on the stopper first. The parts are dried and burnt, and then fall into the grate through the perforations on it and burn out, and the combustion is more complete.

The above invention and the prior art incinerate the garbage only through simple sorting and then put it into the incinerator. However, due to the unstable composition of the garbage, the high moisture content, and the large difference in combustion characteristics, the combustion effect is poor and the oxygen supply is insufficient. The quality of tail gas emissions is poor, and the combustion of slag is incomplete, causing secondary pollution problems.

SUMMARY OF THE INVENTION

In order to solve the above problems, the present invention provides a method for co-processing domestic waste in a cement kiln.

A method for co-processing domestic waste in a cement kiln, the main scheme of which is:

First, the domestic garbage is leached, and the liquid seepage is initially separated; then the garbage enters the sorting system, and the domestic garbage to be processed is sorted, and the non-combustible hard materials such as metals and stones in the garbage are sorted out. ; Then the sorted garbage is crushed into the crushing system, and the crushed block size of the garbage is required to be 10-50mm; the crushed garbage blocks enter the drying system, and the moisture content of the broken garbage blocks is dried to 10%-25% ; After drying, the broken pieces of garbage enter the mixing bin, add 2%-8% of molding aids and 13%-25% of auxiliary fuel, fully mix and evenly enter into the granulation equipment for extrusion granulation, The garbage particles are irregular particles with a particle size of 10-50mm; the completed garbage particles enter the drying system again, and the moisture content of the garbage particles is dried to 1%-5%; finally, the obtained garbage particles are put into In the pyrolysis furnace, the decomposition furnace is divided into a negative pressure decomposition furnace and a combustion furnace. The temperature of the negative pressure decomposition furnace is 900-1100 ° C, and the oxygen concentration is 3%-7%; the combustion furnace controls The decomposition temperature is 1200-1500 ℃, and the oxygen concentration is controlled to be 13%-18%; the garbage particles are first pyrolyzed in the negative pressure decomposition furnace, and then enter the combustion furnace for decomposition; the decomposed slag ash is mixed with cement raw meal, as The raw material for the production of cement clinker enters the rotary kiln and is calcined at 1300-1500 ℃.

The molding aid is a molding aid obtained by modifying waste plastics, and silane-succinate starch is prepared by using vinyltetramethyldisilane and sodium octenyl starch succinate;

The molding aid is a molding aid obtained by modification of waste plastics, and uses silane-starch succinate, zinc maleate and waste plastic particles to extrude graft polymerization reaction in several molten states;

Described silane-succinic acid starch, its preparation method is as follows:

According to the parts by mass, add 20-53 parts of vinyltetramethyldisilane, 0.05-2 parts of platinum-carbon catalyst, 300-355 parts of white oil into the reaction kettle, under nitrogen protection, stir for 100-200min, then 40 parts -65 parts of sodium starch octenyl succinate is slowly added to the autoclave, heated to be raised to 80-92° C., the pressure of the reaction vessel is controlled to be 0.5-1MPa, and the reaction is maintained for 60-180min. The reaction finishes, and the white oil is removed by vacuum distillation. Filter, dry, obtain silane-succinic acid starch;

This step is a hydrosilylation reaction, and some of the reactions are shown as:

According to the parts by mass, 180-255 parts of waste plastic particles, 2-7 parts of silane-succinic acid starch, 0.2-0.7 parts of diisopropyl peroxydicarbonate, 10-20 parts of zinc maleate were added Go to the high-speed mixing kettle, control the temperature to 40-60℃, stir and mix at a high speed for 30-60min, then add 5-15 parts of polyethylene wax into the mixing kettle, continue mixing for 10-20min, and then take it out and put it into extrusion after completion. In the machine, the molding aids are obtained after extrusion and granulation;

Described silane-starch succinate, zinc maleate and waste plastic granules are extruded under several molten states and undergo graft polymerization reaction, and some of the reactions are shown as:

The waste plastic granules include 40%-55% waste plastic bottle granules, 10%-15% waste greenhouse film granules, 12%-20% waste pipe material granules, and other components are waste foam granules.

The granulation equipment is a single-screw extrusion granulator or a twin-screw extrusion granulator.

The flue gas generated by pyrolysis in the negative pressure decomposition furnace enters the combustion furnace through the high pressure fan and is fully burned.

The auxiliary fuel is coal or heavy oil or coke.

The slag ash obtained by the decomposition is mixed with the cement raw meal in the proportion of 10%-25%.

The heat in the flue gas of the cement kiln provides heat for the waste drying system.

The temperature in the granulation equipment is 80-120°C.

The present invention provides a method for co-processing domestic waste in a cement kiln. The present invention converts the domestic waste into a product with stable calorific value, uniform quality, stable composition, and easy combustion by adding a molding aid obtained by modifying cheap waste and old plastics. The granular cement kiln fuel combines the characteristics of high temperature of the cement kiln, large waste heat, and utilization of residues, making full use of the waste heat of the cement kiln to dry the waste, using the incinerated ash as the raw material for cement production, and turning domestic waste into treasure; the present invention Through the two-stage incineration technology, firstly the waste pellets are thermally decomposed at a high temperature in a low oxygen environment, and then the decomposed solids and gases are introduced into the combustion chamber for full combustion; the invention solves the problem of poor combustion effect of household waste and poor exhaust gas quality. Problems such as incomplete combustion of slag will not cause secondary pollution problems.

Description of drawings

Fig. 1 is the Fourier transform infrared spectrum of the silane-succinate starch sample prepared in Example 2.

There is an absorption peak of ester carbonyl around 1732cm ^-1 , an absorption peak of ester carbon-oxygen single bond around 1136cm ^-1 , an ether absorption peak around 1067cm ^-1 , and an absorption peak of hydroxyl around 3328cm ^-1 , indicating that Sodium starch octenyl succinate participated in the reaction; there is a stretching absorption peak of carbon and hydrogen around 2964cm ^-1 , a stretching absorption peak of silicon carbon around 729cm ^-1 , and an antisymmetry of silicon and oxygen around 1030/865cm ^-1 / Symmetric stretching absorption peak, indicating that vinyltetramethyldisilane participated in the reaction.

Detailed ways

This invention is further described below by specific embodiment:

In this experiment, according to the Chinese standard GWKB3-2000, the content of soot and the content of dioxin and furan in the flue gas after incineration were determined.

Example 1

A method for co-processing domestic waste in a cement kiln, the main scheme of which is:

First, the domestic garbage is leached, and the liquid seepage is initially separated; then the garbage enters the sorting system, and the domestic garbage to be processed is sorted, and the non-combustible hard materials such as metals and stones in the garbage are sorted out. ; Then put the sorted garbage into the crushing system for crushing, and the crushed block size of the garbage is required to be 10mm; the crushed garbage blocks enter the drying system, and the moisture content of the broken garbage blocks is dried to 10%; The broken pieces of garbage enter the mixing bin, add 2% of molding aids and 13% of auxiliary fuel, fully mix and evenly enter into the granulation equipment for extrusion and granulation. Regular particles; the completed garbage particles enter the drying system again, and the moisture content of the garbage particles is dried to 1%; finally, the obtained garbage particles are put into the pyrolysis furnace, and the decomposition furnace is divided into negative pressure decomposition Furnace and combustion furnace, the temperature of the negative pressure decomposition furnace is 900 ° C, and the oxygen concentration is 3%; the control decomposition temperature of the combustion furnace is 1200 ° C, and the control oxygen concentration is 13%; the garbage particles are first in the negative pressure decomposition furnace. The slag ash obtained from the decomposition is mixed with the cement raw meal, and then enters the rotary kiln as the raw material for the production of cement clinker, and is calcined at 1300 ℃.

Described silane-succinic acid starch, its preparation method is as follows:

Vinyl tetramethyldisilane of 20kg and 0.05kg platinum carbon catalyst, the white oil of 300kg are added in the reactor, nitrogen protection, stir 100min, then slowly join in the autoclave with the sodium starch octenyl succinate of 40kg , heating up to 80 ° C, controlling the pressure of the reactor to 0.5 MPa, holding the reaction for 60 min, the reaction was completed, vacuum distillation to remove white oil, filtration, and drying to obtain silane-succinic acid starch;

The waste plastic particles of 180kg, the silane-succinate starch of 2kg, the diisopropyl peroxydicarbonate of 0.2kg, and the zinc maleate of 10kg were added to the high-speed mixing kettle, and the temperature was controlled at 40 ° C, and the high-speed stirring was mixed for 30min. Then add 5kg of polyethylene wax into the mixing kettle, continue to mix for 10min, take it out and put it into the extruder after completion, and extrude and granulate to obtain a molding aid;

The granulation equipment is a single screw extrusion granulator.

The flue gas generated by pyrolysis in the negative pressure decomposition furnace enters the combustion furnace through the high pressure fan and is fully burned.

The auxiliary fuel is coal.

The slag ash obtained by the decomposition is mixed with the cement raw meal in a proportion of 10%.

The heat in the flue gas of the cement kiln provides heat for the waste drying system.

The temperature in the granulation equipment is 80°C.

The content of soot in the flue gas after incineration in this experiment was 0.89mg/m ³ , and the content of dioxin and furan was 0.012ng/m ³ .

Example 2

A method for co-processing domestic waste in a cement kiln, the main scheme of which is:

First, the domestic garbage is leached, and the liquid seepage is initially separated; then the garbage enters the sorting system, and the domestic garbage to be processed is sorted, and the non-combustible hard materials such as metals and stones in the garbage are sorted out. ; Then the sorted garbage enters the crushing system to be crushed, and the crushing block size of the garbage is required to be 30mm; the crushed garbage blocks enter the drying system, and the moisture content of the broken garbage blocks is dried to 15%; The broken pieces of garbage enter the mixing bin, add 6% of molding aids and 18% of auxiliary fuel, fully mix and then enter into the granulation equipment for extrusion and granulation. Regular particles; the completed garbage particles enter the drying system again, and the moisture content of the garbage particles is dried to 3%; finally, the obtained garbage particles are put into the pyrolysis furnace, and the decomposition furnace is divided into negative pressure decomposition Furnace and combustion furnace, the temperature of the negative pressure decomposition furnace is 1000 ° C, and the oxygen concentration is 5%; the control decomposition temperature of the combustion furnace is 1400 ° C, and the control oxygen concentration is 15%; the garbage particles are first in the negative pressure decomposition furnace. It is pyrolyzed in the middle, and then enters the combustion furnace for decomposition; the slag ash obtained from the decomposition is mixed with the cement raw meal, and enters the rotary kiln as the raw material for the production of cement clinker, and is calcined at 1400 ° C.

Described silane-succinic acid starch, its preparation method is as follows:

The vinyl tetramethyldisilane of 29kg and 0.1kg platinum carbon catalyst, the white oil of 325kg are added in the reactor, nitrogen protection, stirs 120min, then the sodium starch octenyl succinate of 46kg is slowly added in the autoclave , heating up to 83 ℃, controlling the pressure of the reactor to 0.6MPa, holding the reaction for 90min, the reaction was finished, vacuum distillation to remove the white oil, filtration, and drying to obtain silane-succinic acid starch;

The waste plastic particles of 194kg, the silane-succinic acid starch of 4kg, the diisopropyl peroxydicarbonate of 0.6kg, and the zinc maleate of 15kg were added to the high-speed mixing kettle, and the temperature was controlled at 45 ℃, and the high-speed stirring was mixed for 52min. Then add 10kg of polyethylene wax into the mixing kettle, continue to mix for 14min, take it out and put it into the extruder after completion, and then extrude and granulate to obtain a molding aid;

The granulation equipment is a twin screw extrusion granulator.

The flue gas generated by pyrolysis in the negative pressure decomposition furnace enters the combustion furnace through the high pressure fan and is fully burned.

The auxiliary fuel is heavy oil.

The slag ash obtained by the decomposition is mixed with the cement raw meal in a proportion of 15%.

The heat in the flue gas of the cement kiln provides heat for the waste drying system.

The temperature in the granulation equipment is 100°C.

The content of soot in the flue gas after incineration in this experiment was 0.84mg/m ³ , and the content of dioxin and furan was 0.008ng/m ³ .

Example 3

A method for co-processing domestic waste in a cement kiln, the main scheme of which is:

First, the domestic garbage is leached, and the liquid seepage is initially separated; then the garbage enters the sorting system, and the domestic garbage to be processed is sorted, and the non-combustible hard materials such as metals and stones in the garbage are sorted out. ; Then the sorted garbage enters the crushing system to be crushed, and the crushed block size of the garbage is required to be 50mm; the crushed garbage blocks enter the drying system, and the moisture content of the broken garbage blocks is dried to 25%; The broken pieces of garbage enter the mixing bin, add 8% of molding aids and 25% of auxiliary fuel, fully mix and then enter into the granulation equipment for extrusion granulation. Regular particles; the completed garbage particles enter the drying system again, and the moisture content of the garbage particles is dried to 5%; finally, the obtained garbage particles are put into the pyrolysis furnace, and the decomposition furnace is divided into negative pressure decomposition Furnace and combustion furnace, the temperature of the negative pressure decomposition furnace is 1100 ° C, and the oxygen concentration is 7%; the control decomposition temperature of the combustion furnace is 1500 ° C, and the control oxygen concentration is 18%; the garbage particles are first in the negative pressure decomposition furnace. It is pyrolyzed in the middle, and then enters the combustion furnace for decomposition; the slag ash obtained from the decomposition is mixed with the cement raw meal, and enters the rotary kiln as the raw material for the production of cement clinker, and is calcined at 1500 ℃.

Described silane-succinic acid starch, its preparation method is as follows:

The vinyltetramethyldisilane of 53kg and the platinum carbon catalyst of 2kg, the white oil of 355kg are added in the autoclave, nitrogen protection is stirred 200min, then the sodium starch octenylsuccinate of 65kg is slowly added in the autoclave, Heating and raising the temperature to 92°C, controlling the pressure of the reactor to 1MPa, holding the reaction for 180min, and finishing the reaction, vacuum distillation to remove white oil, filtration, and drying to obtain silane-succinate starch;

The waste plastic particles of 255kg, the silane-succinic acid starch of 7kg, the diisopropyl peroxydicarbonate of 0.7kg, and the zinc maleate of 20kg were added to the high-speed mixing kettle, and the temperature was controlled at 60 ° C, and the high-speed stirring was mixed for 60min. Then add 15kg of polyethylene wax into the mixing kettle, continue to mix for 20min, take it out and put it into the extruder after completion, and extrude and granulate to obtain a molding aid;

The granulation equipment is a single screw extrusion granulator.

The flue gas generated by pyrolysis in the negative pressure decomposition furnace enters the combustion furnace through the high pressure fan and is fully burned.

The auxiliary fuel is coke.

The slag ash obtained by the decomposition is mixed with the cement raw meal in a proportion of 25%.

The heat in the flue gas of the cement kiln provides heat for the waste drying system.

The temperature in the granulation equipment is 120°C.

The content of soot in the flue gas after incineration in this experiment was 0.82mg/m ³ , and the content of dioxin and furan was 0.007ng/m ³ .

Comparative Example 1

A method for co-processing domestic waste in a cement kiln, the main scheme of which is:

A method for co-processing domestic waste in a cement kiln, the main scheme of which is:

First, the domestic garbage is leached, and the liquid seepage is initially separated; then the garbage enters the sorting system, and the domestic garbage to be processed is sorted, and the non-combustible hard materials such as metals and stones in the garbage are sorted out. ; Then put the sorted garbage into the crushing system for crushing, and the crushed block size of the garbage is required to be 10mm; the crushed garbage blocks enter the drying system, and the moisture content of the broken garbage blocks is dried to 10%; The broken pieces of garbage enter the mixing bin, add 2% of molding aids and 13% of auxiliary fuel, fully mix and evenly enter into the granulation equipment for extrusion and granulation. Regular particles; the completed garbage particles enter the drying system again, and the moisture content of the garbage particles is dried to 1%; finally, the obtained garbage particles are put into the pyrolysis furnace, and the decomposition furnace is divided into negative pressure decomposition Furnace and combustion furnace, the temperature of the negative pressure decomposition furnace is 900 ° C, and the oxygen concentration is 3%; the control decomposition temperature of the combustion furnace is 1200 ° C, and the control oxygen concentration is 13%; the garbage particles are first in the negative pressure decomposition furnace. The slag ash obtained from the decomposition is mixed with the cement raw meal, and then enters the rotary kiln as the raw material for the production of cement clinker, and is calcined at 1300 ℃.

The waste plastic particles of 180kg, the silane-succinate starch of 2kg, the diisopropyl peroxydicarbonate of 0.2kg, and the zinc maleate of 10kg were added to the high-speed mixing kettle, and the temperature was controlled at 40 ° C, and the high-speed stirring was mixed for 30min. Then add 5kg of polyethylene wax into the mixing kettle, continue to mix for 10min, take it out and put it into the extruder after completion, and extrude and granulate to obtain a molding aid;

The granulation equipment is a single screw extrusion granulator.

The flue gas generated by pyrolysis in the negative pressure decomposition furnace enters the combustion furnace through the high pressure fan and is fully burned.

The slag ash obtained by the decomposition is mixed with the cement raw meal in a proportion of 10%.

The heat in the flue gas of the cement kiln provides heat for the waste drying system.

The temperature in the granulation equipment is 80°C.

The content of soot in the flue gas after incineration in this experiment was 12.42mg/m ³ , and the content of dioxin and furan was 0.624ng/m ³ .

Comparative Example 2

A method for co-processing domestic waste in a cement kiln, the main scheme of which is:

First, the domestic garbage is leached, and the liquid seepage is initially separated; then the garbage enters the sorting system, and the domestic garbage to be processed is sorted, and the non-combustible hard materials such as metals and stones in the garbage are sorted out. ; Then put the sorted garbage into the crushing system for crushing, and the crushed block size of the garbage is required to be 10mm; the crushed garbage blocks enter the drying system, and the moisture content of the broken garbage blocks is dried to 10%; The broken pieces of garbage enter the mixing bin, add 2% of molding aids and 13% of auxiliary fuel, fully mix and evenly enter into the granulation equipment for extrusion and granulation. Regular particles; the completed garbage particles enter the drying system again, and the moisture content of the garbage particles is dried to 1%; finally, the obtained garbage particles are put into the pyrolysis furnace, and the decomposition furnace is divided into negative pressure decomposition Furnace and combustion furnace, the temperature of the negative pressure decomposition furnace is 900 ° C, and the oxygen concentration is 3%; the control decomposition temperature of the combustion furnace is 1200 ° C, and the control oxygen concentration is 13%; the garbage particles are first in the negative pressure decomposition furnace. The slag ash obtained from the decomposition is mixed with the cement raw meal, and then enters the rotary kiln as the raw material for the production of cement clinker, and is calcined at 1300 ℃.

Described silane-succinic acid starch, its preparation method is as follows:

Vinyl tetramethyldisilane of 20kg and 0.05kg platinum carbon catalyst, the white oil of 300kg are added in the reactor, nitrogen protection, stir 100min, then slowly join in the autoclave with the sodium starch octenyl succinate of 40kg , heating up to 80 ° C, controlling the pressure of the reactor to 0.5 MPa, holding the reaction for 60 min, the reaction was completed, vacuum distillation to remove white oil, filtration, and drying to obtain silane-succinic acid starch;

180kg of waste plastic granules, 2kg of silane-succinic acid starch, 0.2kg of diisopropyl peroxydicarbonate were added to the high-speed mixing kettle, the temperature was controlled at 40°C, and the mixture was stirred and mixed at a high speed for 30min, and then 5kg of polyethylene The wax is added to the mixing kettle, and the mixing is continued for 10 minutes. After completion, the wax is taken out and put into the extruder, and the molding aid is obtained after extrusion and granulation;

The granulation equipment is a single screw extrusion granulator.

The flue gas generated by pyrolysis in the negative pressure decomposition furnace enters the combustion furnace through the high pressure fan and is fully burned.

The auxiliary fuel is coal.

The slag ash obtained by the decomposition is mixed with the cement raw meal in a proportion of 10%.

The heat in the flue gas of the cement kiln provides heat for the waste drying system.

The temperature in the granulation equipment is 80°C.

The content of soot in the flue gas after incineration in this experiment was 10.11 mg/m ³ , and the content of dioxin and furan was 0.517 ng/m ³ .

Comparative Example 3

A method for co-processing domestic waste in a cement kiln, the main scheme of which is:

First, the domestic garbage is leached, and the liquid seepage is initially separated; then the garbage enters the sorting system, and the domestic garbage to be processed is sorted, and the non-combustible hard materials such as metals and stones in the garbage are sorted out. ; Then the sorted garbage enters the crushing system to be crushed, and the crushed block size of the garbage is required to be 10mm; the crushed garbage blocks enter the drying system, and the moisture content of the broken garbage blocks is dried to 10%; The broken garbage enters the mixing bin, and 13% of the auxiliary fuel is fully mixed and then enters the granulation equipment for extrusion and granulation. The garbage particles are irregular particles with a particle size of 10mm; the completed garbage particles are Entering the drying system again, the moisture content of the garbage particles is dried to 1%; finally, the obtained garbage particles are put into the pyrolysis furnace, and the decomposition furnace is divided into a negative pressure decomposition furnace and a combustion furnace. The temperature of the negative pressure decomposition furnace is 900 °C, and the oxygen concentration is 3%; the control decomposition temperature of the combustion furnace is 1200 °C, and the control oxygen concentration is 13%; the garbage particles are first pyrolyzed in the negative pressure decomposition furnace, and then enter the combustion furnace. Decomposed in the furnace; the slag ash obtained from the decomposition is mixed with the cement raw meal, and then enters the rotary kiln as the raw material for the production of cement clinker, and is calcined at 1300 ℃.

The granulation equipment is a single screw extrusion granulator.

The flue gas generated by pyrolysis in the negative pressure decomposition furnace enters the combustion furnace through the high pressure fan and is fully burned.

The auxiliary fuel is coal.

The slag ash obtained by the decomposition is mixed with the cement raw meal in a proportion of 10%.

The heat in the flue gas of the cement kiln provides heat for the waste drying system.

The temperature in the granulation equipment is 80°C.

The content of soot in the flue gas after incineration in this experiment was 102.36 mg/m ³ , and the content of dioxin and furan was 5.63 ng/m ³ .

Claims (7)

1. A method for cooperatively treating household garbage by a cement kiln is characterized by comprising the following steps:

firstly, domestic garbage is subjected to leaching treatment, and liquid seepage is preliminarily separated; then the obtained garbage enters a sorting system to sort the household garbage to be treated, and non-combustible hard materials such as metal, stones and the like in the garbage are sorted out; then, the sorted garbage enters a crushing system to be crushed, and the crushing lumpiness of the garbage is required to be 10-50 mm; the crushed garbage blocks enter a drying system, and the moisture content of the garbage blocks is dried to 10-25%; feeding the dried garbage fragments into a mixing bin, adding 2-8% of forming aid and 13-25% of auxiliary fuel, fully and uniformly mixing, and feeding into granulation equipment for extrusion granulation to obtain garbage particles, wherein the garbage particles are irregular particles with the particle size of 10-50 mm; the finished garbage particles enter a drying system again, and the moisture content of the garbage particles is dried to 1% -5%; finally, putting the obtained garbage particles into a pyrolysis furnace, wherein the pyrolysis furnace is divided into a negative pressure decomposition furnace and a combustion furnace, the temperature of the negative pressure decomposition furnace is 900-1100 ℃, and the oxygen concentration is 3-7%; the combustion furnace controls the decomposition temperature to be 1200-1500 ℃, and controls the oxygen concentration to be 13-18%; firstly, pyrolyzing the garbage particles in a negative pressure decomposing furnace, and then, feeding the garbage particles into a combustion furnace for decomposition; mixing the decomposed slag ash with cement raw materials, feeding the slag ash serving as a production raw material of cement clinker into a rotary kiln, and calcining at 1300-1500 ℃;

the forming auxiliary agent is obtained by modifying waste plastics, and silane-succinic acid starch prepared by vinyl tetramethyl disilane and sodium starch octenyl succinate is used as a raw material;

the preparation method of the silane-succinic acid starch comprises the following steps:

according to the mass parts, 20-53 parts of vinyl tetramethyl disilane, 0.05-2 parts of platinum carbon catalyst and 355 parts of white oil with 300-25 parts of organic nitrogen protection are added into a reaction kettle, stirred for 100-200min, then 40-65 parts of sodium starch octenyl succinate are slowly added into a high-pressure reaction kettle, heated to 80-92 ℃, the pressure of the reaction kettle is controlled to be 0.5-1MPa, the reaction is carried out for 60-180min under the condition of heat preservation, the reaction is finished, the white oil is removed by vacuum distillation, and the silane-starch succinate is obtained after filtration and drying;

the forming assistant is obtained by modifying waste plastics, and the preparation method comprises the following steps:

adding 180-255 parts of waste plastic particles, 2-7 parts of silane-succinic acid starch, 0.2-0.7 part of diisopropyl peroxydicarbonate and 10-20 parts of zinc maleate into a high-speed mixing kettle according to the mass parts, controlling the temperature to be 40-60 ℃, stirring and mixing at a high speed for 30-60min, then adding 5-15 parts of polyethylene wax into the mixing kettle, continuously mixing for 10-20min, taking out and putting into an extruder after the mixing is finished, and obtaining the forming aid after extrusion granulation.

2. The method for the cement kiln to dispose domestic garbage in coordination with the claim 1, wherein: the granulating equipment is a single-screw extrusion granulator or a double-screw extrusion granulator.

3. The method for the cement kiln to dispose domestic garbage in coordination with the claim 1, wherein: and the flue gas generated by pyrolysis in the negative pressure decomposing furnace enters the combustion furnace through the high-pressure fan to be fully combusted.

4. The method for the cement kiln to dispose domestic garbage in coordination with the claim 1, wherein: the auxiliary fuel is coal or heavy oil or coke.

5. The method for the cement kiln to dispose domestic garbage in coordination with the claim 1, wherein: the slag ash obtained by decomposition is doped into the cement raw material according to the proportion of 10-25%.

6. The method for the cement kiln to dispose domestic garbage in coordination with the claim 1, wherein: the heat in the cement kiln flue tail gas supplies heat for the garbage drying system.

7. The method for the cement kiln to dispose domestic garbage in coordination with the claim 1, wherein: the temperature in the granulating equipment is 80-120 ℃.

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