JP5018754B2 - Processing method of shredder dust using cement manufacturing process - Google Patents

Description

  The present invention relates to a processing method for stably processing shredder dust generated during recycling of an automobile or the like using a cement manufacturing process for manufacturing a cement clinker.

  In recent years, along with the application of the recycling law to various automobiles and electrical appliances such as air conditioners, televisions, refrigerators and washing machines discharged from ordinary households or offices, the above-mentioned automobiles and home appliances have been dismantled and "pre-sorting process" It is obliged to collect “items”.

  As a result, for example, with respect to the automobile, first, parts such as airbags, tires, batteries, etc. listed in the pre-sorting parts are collected by a dismantling contractor, and then cut by a shredder, and further, a wire harness or a print It is called ASR (Automobile Shredder Residue), which contains a lot of various plastics, rubber, glass, foamed urethane, etc. as residue by separating and recovering reusable metals such as part of the substrate Shredder dust is generated.

The shredder dust generated in this way is said to occupy about 20% of the weight of the dismantled vehicle, and the amount generated is constantly increasing year by year.
On the other hand, as the method for treating the shredder dust, previously it was exclusively landfill treatment, but it has become difficult to secure a landfill treatment site, and in particular, the bulk specific gravity of the shredder dust is about 0.1. There is a problem that it is as small as about 0.2.

For this reason, various methods for separately treating this kind of shredder dust independently of landfill are being developed.
For example, in the following Patent Document 1, the shredder dust is heated and pressurized with a solvent such as light oil or heavy oil in the presence of an inert gas and dissolved in a liquid phase, whereby the organic component contained in the shredder dust is a liquid component or There has been proposed a shredder dust treatment method in which the liquid component or gas is reused as fuel or the like, and the residue is washed with water to recover a metal such as aluminum.

  However, in the above processing method, in order to dissolve the shredder dust in the liquid phase, it is necessary to add an inert gas or a solvent, and additionally a heating device or a pressurizing device is required. There is a problem in that energy and equipment are required, and thus processing costs generally increase.

  Further, in Patent Document 2 below, after removing the metal piece from the shredder dust in the metal sorting step, it is separated into a plastic piece and a combustible material piece by a specific gravity difference, and the separated plastic piece and the combustible material piece are subjected to desired heat generation. There has been proposed a method for recycling shredder dust, which is made into a waste plastic solid fuel by blending it in a proportion corresponding to the amount and press molding.

However, the conventional shredder dust recycling method also has a problem that a molding machine for molding the waste plastic solid fuel is required. In addition, since the plastic piece and the combustible piece are mixed in a ratio that provides the desired calorific value, one with a large amount of discharge still remains as waste, and a separate treatment is required for that purpose. There is a problem.
JP 2004-275889 A JP 2006-181520 A

  The present invention has been made in view of such circumstances, and processing of shredder dust using a cement manufacturing process capable of processing shredder dust while effectively using it without requiring additional equipment or energy. It is an object to provide a method.

In order to solve the above-mentioned problem, the invention according to claim 1 supplies the cement raw material from the kiln bottom side of the cement kiln whose inside is maintained in a high temperature atmosphere by the main burner provided on the kiln front side, a method for processing shredder dust with cement manufacturing process of firing while feeding the kiln front, shredder dust (ASR) generated during dismantling of automobiles, lightweight dust and incombustible component mainly comprising combustible matter by the difference in specific gravity It is separated into heavy dust as the main component, and the light dust is put into the kiln before the kiln of the cement kiln and burned to be a part of the fuel for the main burner, and the heavy dust is combined with the cement raw material. with a part of the cement material is introduced into the cement kiln, to detect the concentration of chlorine in the exhaust gas in the kiln inlet, the salt When the concentration exceeds 7000 ppm, by increasing the specific gravity difference of the separation, the amount of the heavy dust introduced into the cement kiln from the kiln bottom is reduced, and the light dust introduced into the kiln before the kiln. When the chlorine concentration exceeds 10,000 ppm, the heavy dust is stopped from being charged .

The invention according to claim 2 is the invention according to claim 1, wherein when the shredder dust is separated into the lightweight dust and the heavy dust, after the nonferrous metal is separated and recovered from the heavy dust. The remaining heavy dust is introduced into the cement kiln together with the cement raw material.

The invention according to claim 3 is the invention according to claim 1 or 2 , wherein the lightweight dust is introduced into the cement kiln together with compressed air from an auxiliary burner provided adjacent to the main burner. It is characterized by being thrown toward.

In addition, in the inventions according to claims 1 to 3 , introducing heavy dust into a cement kiln together with a cement raw material means that the separated heavy dust needs to be further crushed to reduce the particle size. Is put into a dry mill for pulverizing and mixing cement raw materials such as limestone, clay, silica and iron oxide raw materials in the most upstream process of the cement manufacturing process, and finally mixed with the cement raw materials while being pulverized. It introduces into the inside from the kiln bottom of the cement kiln.

  In addition, if the particle size is reduced to such a level that there is no problem even if it is mixed with the cement raw material as it is, for example, by crushing the above heavy dust in the separation step in advance, directly from the kiln bottom part of the cement kiln to the inside It is also possible to input.

  At this time, the kiln bottom part that can be charged is a kiln bottom casing that rotatably supports the cement kiln on the kiln bottom side of the cement kiln and a preheater that preheats the cement raw material on the upstream side of the cement kiln. If there is a calcining furnace in the upstream of the transfer pipe from the preheater to the casing and the cement kiln, this is the calcining furnace.

In the invention according to any one of claims 1 to 3 , first, in the cement manufacturing process, a cement clinker is manufactured by firing a cement raw material in a high temperature atmosphere of about 1450 ° C. in a cement kiln. Therefore, a light dust mainly composed of combustible matter separated from shredder dust, the cement kiln is put into the kiln before the kiln, and the combustible component is burned by the flame of the main burner, so that the fuel of the main burner Can be processed as part of

The cement raw material contains limestone (CaCO ₃ ), clay, silica and iron oxide raw materials, that is, SiO ₂ , Al ₂ O ₃ and Fe ₂ O ₃ . For this reason, iron and glass (SiO ₂ ), which are main components of the heavy dust separated from the shredder dust, are finally introduced into the inside of the kiln bottom portion of the cement kiln, and together with the cement raw material. It is fired in a cement kiln and used as part of the cement raw material. In addition, the combustible part contained in the said heavy dust is utilized as a part of fuel similarly by combusting before introduce | transducing in a cement kiln.

Here, when the shredder dust is ASR as in the present invention, the shredder dust generally includes paper, cloth, wood, plastics, rubber, and the like as combustible materials. Incombustible materials include glass and metals such as iron, aluminum, and copper. For this reason, as described above, the combustible material can be used as part of the fuel for the main burner by burning in the cement kiln. Moreover, iron, glass, and aluminum can be used as a part of the cement raw material.

  Therefore, when separating the shredder dust into light dust and heavy dust, there is no need to strictly separate the combustible and heavy dust, and the cement kiln is maintained in a high temperature atmosphere of about 1450 ° C. Therefore, even if combustible components are mixed in heavy dust, when combustible components are pulverized and mixed together with cement raw materials, they are put into the kiln bottom part directly in the cement raw material preheating process. If this happens, it will burn in the cement kiln at the latest.

  On the other hand, if the amount of incombustible components in the light dust is large, the mixture is thrown into the cement kiln from the front side of the kiln and may not be sufficiently fired. For this reason, when separating the lightweight dust from the heavy dust, there is no problem even if flammable materials are mixed in the heavy dust, and conversely, the specific gravity difference is such that the amount of incombustible components in the lightweight dust is minimized. It is preferable to set and sort.

  In addition, although other metals, such as copper, remain in the cement raw material, the content of the cement raw material with respect to the total amount of the cement raw material is extremely small, so there is no possibility of adversely affecting the quality of the manufactured cement clinker.

Incidentally, when the shredder dust is ASR, as shown in Table 1, urethanes, hard plastics, soft plastics, the chloride concentration of the rubber and the like contains many high member. Of these members, those having a large specific gravity are separated into heavy dust and introduced into the kiln bottom of the cement kiln.

  On the other hand, in this type of cement manufacturing facility, it is known that when the chlorine concentration in the exhaust gas in the kiln bottom exceeds approximately 10,000 ppm, the cyclone at the lower part of the preheater is likely to be blocked. It is also known that when the chlorine concentration rises rapidly, the growth rate of coating (adhered matter) increases, and it becomes easier to block.

In this regard, according to the present invention, the chlorine concentration in the exhaust gas in the kiln bottom is detected, and when the chlorine concentration exceeds 7000 ppm, the specific gravity difference in the separation is increased, so that The amount of heavy dust introduced into the furnace is decreased and the amount of light dust introduced into the furnace from before the kiln is increased. Further, when the chlorine concentration exceeds 10,000 ppm, the heavy dust injection is stopped. In addition, it is possible to prevent such adverse effects from occurring and to ensure stable operation.

In addition, when metals such as copper are contained in the shredder dust, these metals are generally precious and easy to reuse, so as in the invention according to claim 2 , When separating the shredder dust into light dust and heavy dust, after separating and collecting the non-ferrous metal such as copper, the remaining heavy dust is put into the kiln bottom part, which further meets the purpose of recycling. Therefore, it is possible to perform an economical process.

  In addition, for example, most of the copper in the heavy dust is present in a form covered with a coating having a high chlorine concentration such as vinyl chloride. Therefore, by removing the copper, the copper in the heavy dust can be simultaneously removed. The effect that chlorine content can also be reduced significantly is acquired.

Furthermore, since the light-weight dust thrown into the kiln front side of the cement kiln has an extremely small bulk specific gravity as described above, an auxiliary burner is provided adjacent to the main burner of the cement kiln as described in claim 3. If it is provided and introduced into the cement kiln with compressed air from the auxiliary burner, it can be easily and smoothly burned by the flame of the main burner.

(First embodiment)
FIG. 1 shows a cement production facility and an ASR separation facility for carrying out a first embodiment of a shredder dust treatment method using a cement production process according to the present invention.
First, the cement manufacturing facility will be described. Reference numeral 1 in FIG. 1 denotes a cement kiln for firing cement raw materials. This cement kiln 1 is a rotary kiln provided so as to be rotatable around an axis, and a preheater 3 for preheating the cement raw material is provided in a left kiln bottom portion 2 in the figure, and a right kiln in the figure. A main burner 5 for heating the inside is provided in front of the kiln 4. In addition, the code | symbol 6 in a figure is a clinker cooler for cooling the cement clinker after baking.

  Here, the preheater 3 is composed of a plurality of cyclones arranged in series in the vertical direction, and the cement raw material is supplied to the uppermost cyclone via the supply pipe 7, and the lowermost cyclone Connected to the bottom is a transfer pipe 3 a for sending the internal cement raw material to the kiln bottom part 2 of the cement kiln 1.

  On the other hand, the kiln bottom part 2 is provided with an exhaust gas pipe 3b for supplying the combustion exhaust gas discharged from the cement kiln 1 to the lowermost cyclone, and the exhaust gas discharged from the upper part of the uppermost cyclone is Exhaust air (not shown) is exhausted through the exhaust line 8.

In this cement manufacturing facility, an ASR sorting facility 10 is installed.
The ASR separation equipment 10 includes at least a crushing unit that crushes shredder dust (ASR) and a combustible component such as light paper, cloth, and wood based on the difference in specific gravity of the ASR finely broken to a predetermined size by the crushing unit. It is equipped with a wind power classifier that separates into light dust mainly composed of heavy dust and heavy dust mainly composed of incombustible materials such as heavy glass and metals.

  On the other hand, an auxiliary burner 11 is provided in front of the kiln 4 of the cement kiln 1 in the cement manufacturing facility. The auxiliary burner 11 is disposed above the main burner 5 at a predetermined interval. A supply pipe 12 is connected to the auxiliary burner 11, and an air pipe 13 for supplying compressed air for conveyance is connected to the supply pipe 12.

The lightweight dust separated by the ASR separation equipment 10 is fed into the cement kiln 1 by compressed air 13 from the supply pipe 12 of the auxiliary burner 11.
Further, the heavy dust containing a lot of glass and metals sorted in the ASR sorting equipment 10 is finally introduced into the cement kiln 1 from the kiln bottom portion 2 of the cement kiln 1 together with the cement raw material.

  At this time, the chlorine concentration in the exhaust gas in the kiln bottom part 2 is detected, and when the chlorine concentration exceeds 7000 ppm, the specific gravity difference of the classification in the wind power separator is increased, so that the kiln bottom part 2 When the amount of heavy dust introduced into 1 is reduced, the amount of light dust introduced into the interior from the front of the kiln 4 is increased, and when the chlorine concentration exceeds 10,000 ppm, the heavy dust from the kiln bottom part 2 Is stopped.

Next, an embodiment of the shredder dust processing method according to the present invention using the cement manufacturing facility and the ASR separation facility having the above-described configuration will be described.
First, in this cement manufacturing facility, in a dry mill (not shown), limestone, clay, silica, and iron oxide raw materials that are cement raw materials are pulverized and mixed, and stored in the raw material silo and then sent to the supply pipe 7, It is supplied to the uppermost cyclone of the preheater 3.

  Then, the cement raw material supplied to the uppermost cyclone is preheated by the high-temperature exhaust gas from the cement kiln 1 that rises from the lower as it sequentially falls to the lower cyclone, and finally from the lowermost cyclone. It is introduced into the cement kiln 1 through the transfer pipe 3a. At this time, the kiln bottom part 2 is in a temperature atmosphere of about 900 ° C.

  The cement raw material sent from the kiln bottom portion 2 into the cement kiln 1 is reduced by the combustion exhaust gas from the main burner 5 in the process of gradually feeding the cement kiln 1 toward the front 4 side of the kiln. It is heated to 1450 ° C. and fired to become a clinker. Next, the clinker that has reached the front 4 is dropped into the clinker cooler 6 and sent to the right in the figure. At this time, the air is cooled to a predetermined temperature by the air supplied into the clinker cooler 6 and finally taken out from the clinker cooler 6.

  At the same time, the ASR carried into the cement manufacturing facility is separated into light dust mainly composed of combustible materials and heavy dust mainly composed of non-combustible materials by the wind power sorter in the ASR separation facility 10. And about the lightweight dust which contains many combustibles, it is sent to the auxiliary burner 11 from the supply pipe | tube 12, and in the cement kiln 1 with the compressed air supplied from the air piping 13, toward the flame of the main burner 5 Is inserted. Thereby, it is burned by the high temperature atmosphere in the cement kiln 1 and the flame from the main burner 5.

On the other hand, the heavy dust containing a large amount of incombustibles separated in the ASR separation facility 10 is finally introduced into the cement kiln 1 from the kiln bottom portion 2 together with the cement raw material and fired.
That is, when the particle size of the heavy dust pulverized by the pulverizing means of the ASR separation equipment 10 is still too large to be directly put into the cement kiln 1, the heavy dust is further crushed to reduce the particle size. It is necessary to let

  In such a case, the heavy dust is put into a dry mill for pulverizing and mixing the above-described cement raw material, mixed with the cement raw material while being pulverized, and finally sent from the supply pipe 7 to the preheater 3 It introduces into the cement kiln 1 from the kiln bottom part 2.

  If there is no problem even if the heavy dust pulverized by the pulverizing means is mixed with the cement raw material as it is, the kiln butt that directly supports the kiln butt portion 2 of the cement kiln 1, for example, the cement kiln 1, is rotatably supported. And the transfer pipe 3a from the preheater 3 to the casing.

And the said heavy dust introduced in the cement kiln 1 from the kiln bottom part 2 with the cement raw material is baked with the said cement raw material, and iron and glass in the said heavy dust are finally utilized as a part of cement raw material. Is done.
Depending on the wind power sorter of the ASR sorting equipment, combustible materials such as a relatively heavy plastic lump may be separated as heavy dust, but the combustible materials are also sent from the preheater 3 to the cement kiln 1. Burned in the process.

  Further, in parallel with the above treatment, the chlorine concentration in the exhaust gas in the kiln bottom portion 2 is detected, and when the chlorine concentration exceeds 7000 ppm, the specific gravity difference in the wind separator is increased, thereby increasing the kiln bottom. When the amount of heavy dust introduced from the portion 2 into the cement kiln 1 is decreased, the amount of light dust introduced into the interior from the front 4 of the kiln is increased, and when the chlorine concentration exceeds 10,000 ppm, the kiln bottom portion Stop the heavy dust input from 2.

  Thus, according to the processing method of the shredder dust which consists of the said structure, from the auxiliary burner 11 provided in the front 4 of the kiln 1 of the cement kiln 1, the lightweight dust which mainly consists of the combustible part separated from the shredder dust (ASR) By putting it into the inside and burning it by the flame of the main burner 5, it can be processed after it is effectively used as part of the fuel of the main burner 5.

  Further, the heavy dust separated from the shredder dust (ASR) can be effectively used as a part of the cement raw material by firing in the cement kiln 1 together with the cement raw material. As a result, the shredder dust (ASR) can be processed while effectively using it, without requiring additional equipment or energy.

  In addition, the chlorine concentration in the exhaust gas in the kiln bottom part 2 is detected, and when the chlorine concentration exceeds 7000 ppm, the specific gravity difference of the separation is increased to be introduced into the cement kiln 1 from the kiln bottom part 2. The amount of heavy dust to be reduced is increased, the amount of light dust to be introduced into the interior from the front of the kiln 4 is increased, and when the chlorine concentration exceeds 10,000 ppm, the introduction of the heavy dust is stopped. In addition, it is possible to prevent the occurrence of problems such as the blocking of the cyclone under the preheater and the occurrence of blocking due to an increase in the growth rate of the coaching, thereby ensuring stable operation.

(Second Embodiment)
FIG. 2 shows a second embodiment of the shredder dust processing method according to the present invention. In this processing method, the separation equipment 20 uses the crushing means 21 for crushing the ASR and the crushing means 21 to crush the ASR. Separator 22 for separating and recovering iron from the separated ASR, and non-ferrous separator for separating and recovering non-ferrous metals such as aluminum and copper by interaction of eddy current and magnetic field from ASR from which iron has been separated in magnetic separator 22 23 and ASR after separation of the non-ferrous metal based on the difference in specific gravity, lightweight dust mainly composed of flammable materials such as light paper, cloth, and wood, and weight mainly composed of non-combustible materials such as heavy glass A wind power separator 24 for separating dust is provided.

Therefore, after separating and recovering ferrous and non-ferrous metals from the ASR in the sorting equipment 20 first, it is separated into light dust and heavy dust, and the light dust is similarly sent from the supply pipe 12 to the auxiliary burner 11, Together with the compressed air supplied from the air pipe 13, it is put into the cement kiln 1 toward the flame of the main burner 5.
Then, the heavy dust remaining after the separation of iron and non-ferrous metals from the ASR is finally introduced into the cement kiln 1 together with the cement raw material.

As described above, also by the processing method according to the second embodiment, it is possible to obtain the same effects as those shown in the first embodiment.
In addition, according to this processing method, since non-ferrous metals such as copper and iron, which are valuable as recycling resources, are separated and recovered in advance in the sorting section 20, these recovered metals are separately supplied to a refining facility, etc. By sending it, it becomes possible to reuse it effectively.

  Furthermore, since most of the copper in the heavy dust separated from the ASR exists in a form covered with a coating having a high chlorine concentration such as vinyl chloride, the weight is simultaneously removed by removing the copper. The effect that chlorine content in dust can also be reduced significantly is acquired.

It is a schematic block diagram which shows the cement manufacturing equipment and ASR fractionation equipment for implementing the 1st Embodiment of this invention. It is a flowchart which shows the structure and effect | action of an ARS separation equipment for implementing the 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cement kiln 2 Kiln bottom part 4 In front of kiln 5 Main burner 10, 20 Sorting equipment 11 Auxiliary burner 12 Supply pipe 13 Air piping of compressed air

Claims (3)

Shredder dust treatment using a cement manufacturing process in which cement raw material is supplied from the kiln bottom side of a cement kiln whose interior is maintained in a high-temperature atmosphere by a main burner provided on the front side of the kiln and fired while being sent to the front side of the kiln A method,
Shredder dust (ASR) generated at the time of dismantling of automobiles is separated into lightweight dust mainly composed of combustible components and heavy dust mainly composed of non-combustible components based on the difference in specific gravity, and the lightweight dust is separated from before the kiln of the cement kiln. As a part of the fuel of the main burner by being put inside and burned, and the heavy dust is introduced into the cement kiln together with the cement raw material to become a part of the cement raw material ,
The amount of the heavy dust introduced from the kiln bottom into the cement kiln by detecting the chlorine concentration in the exhaust gas at the kiln bottom and increasing the specific gravity difference when the chlorine concentration exceeds 7000 ppm. A cement manufacturing process characterized by increasing the amount of the lightweight dust introduced into the furnace from before the kiln and stopping the introduction of the heavy dust when the chlorine concentration exceeds 10,000 ppm. The processing method of the shredder dust used. When separating the shredder dust into the lightweight dust and the heavy dust, after separating and collecting the non-ferrous metal from the heavy dust, introducing the remaining heavy dust together with the cement raw material into the cement kiln. The processing method of the shredder dust using the cement manufacturing process of Claim 1 characterized by the above-mentioned. The cement manufacturing process according to claim 1 or 2, wherein the lightweight dust is introduced into the cement kiln together with compressed air from an auxiliary burner provided adjacent to the main burner . How to handle shredder dust.

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