KR101785558B1 - Manufacturing method for solid fuel of organic sludge by using dry pyrolysis gas formed from thermal decomposition of waste - Google Patents

Abstract

The present invention relates to a method and apparatus for recovering energy generated by combustion of a pyrolysis gas obtained by pyrolysis of municipal waste, such as steam, from a boiler, drying carbonized organic sludge using the remaining combustion gas to obtain a solidified fuel of good quality, The present invention relates to a method for producing a solidified fuel compact of an organic sludge produced by using a dry gas, comprising: a pyrolysis step of generating a combustible dry gas obtained by pyrolyzing industrial waste and municipal waste; A combustion process for combusting the combustible dry gas; An energy recovery step of recovering heat energy generated in the combustion of the carbon monoxide gas by the steam in the boiler and supplying the heat to the drier; Mixing the organic sludge with an adjuvant for inhibiting flocculation in an amount of 1 to 15 wt% based on the sludge to prepare a sludge mixture; An injection molding process for molding the sludge mixture produced by the mixture manufacturing process so as to have a certain shape and shape; Wherein the molded article molded by the injection molding process is dried in the dryer so as to have a moisture content of 10 wt% or less, a low calorific value of 3,000 to 3,500 kcal / kg and a carbon content of 40 to 45 wt% on a dry basis, Lt; / RTI >
According to such a method for producing a solidified fuel molded body of organic sludge, it is possible to obtain a high-quality fuel molded body having a high calorific value by using the energy generated by the combustion of the carbonized gas obtained by pyrolyzing municipal wastes and the like.

Description

Technical Field [0001] The present invention relates to a method for producing a solidified fuel compact of an organic sludge produced by using a flammable dry gas of waste,

The present invention relates to a method for producing a solidified fuel compact of an organic sludge produced by using a flammable dry gas of waste, and more particularly, to a method of manufacturing a solidified fuel compact of an organic sludge by using energy generated by combustion of pyrolysis gas obtained by pyrolyzing municipal waste or industrial waste A method for manufacturing a solidified fuel compact of an organic sludge, which is produced by using flammable dry gas of waste, which is obtained by drying carbonized organic sludge by using combustion gas recovered from steam in a boiler and obtaining high quality solidified fuel having high heat amount .

With the depletion of fossil fuels, the need for alternative energy and the pollution of the global environment have increased, global warming, and the increase of various harmful substances, have become an international issue over the national level. It is important to develop municipal waste, industrial wastes, and organic sludge as energy resources and to develop and use alternative energy.

In order to produce a solid fueled product with sewage sludge, the water content of the sludge itself must be lowered. However, there is a limitation in the technology of the dehydration facility currently being operated in the sewage treatment plant. Sewage sludge itself has an average water content of 60 ~ 80wt%. To convert it into fuel, the water content must be reduced to 10wt% or less, which requires a great deal of cost. Development of technology for drying with minimum economic energy is an urgent task for fueling. Sewage sludge organic solid sludge solidification technology is mainly divided into carbonization technology, dry-solidification technology, injection molding technology and pyrolysis technology.

Carbonization technology is an anaerobic or hypoxic state, that is, raw materials are subjected to an incomplete combustion reaction at a high temperature, and oxygen (O ₂ ) atoms contained in the sludge and oxygen atoms containing hydrogen (H ₂ ) (H ₂ ) atoms are burned out with oxygen (O ₂ ) atoms, and only carbon and ashes are left. When organic wastes are carbonized, the sludge can be stabilized and reduced have.

The carbonization process proceeds in the order of drying, dry gas formation, and carbonization depending on the temperature. Molding-injection technology is a technique to mix pellets with sludge and then suppress cohesive force to facilitate injection molding to form pellets and to dry solidified sludge pellets. In addition, pyrolysis technology is primarily a technique for gasifying solid waste, that is, municipal waste or industrial waste, at an appropriate temperature and using it as an energy source through an intermediate process. So it is called pyrolysis gasification technology.

According to the above conventional methods, in order to solidify the sludge, the sludge having a moisture content of 70 to 80 wt% is first dried to a moisture content of less than 10%, mixed with an anthracite such as anthracite, wood and oil, Thereby producing a solid fuel. Most of these conventional solid fuel technologies are different depending on how the sludge is dried or molded in some way. The sludge is dried and then mixed with a heat assistant or a heat assistant and a molding agent, .

The conventional solid fuel conversion technology has the following problems.

First, since the mixture of sludge and caloric aid is formed by compression at high pressure, there is a problem that the gap between the particles is too dense and there is almost no pore or the porosity is too low. These solid fuels are not easy to burn during combustion, take a long time to complete combustion, and generate harmful gas and odor due to incomplete combustion.

Secondly, energy is consumed primarily to dry the sludge, and energy is secondarily consumed in the process of compression-molding the dried sludge at a high pressure. Therefore, there is a problem that a lot of energy is consumed in the process of manufacturing the solid fuel, thereby increasing the manufacturing cost. This discourages the idea of recycling sludge as renewable energy.

Third, since the dried sludge is compression-molded at a high pressure, there is a problem that a separate molding agent or a pressure-sensitive adhesive should be added in order to facilitate molding. This is not only a cause for further lowering the porosity of the solid fuel, but also may cause harmful components in the combustion.

Fourth, in order to uniformly mix the sludge after drying, the dried solid material must be pulverized into powder or dispersed to a maximum degree before drying, so that the facility is complicated and the facility cost is excessively used, resulting in a low economic efficiency .

Thus, the conventional solid fuel technology using sludge is difficult to apply as an effective alternative for recycling as renewable energy due to the above-mentioned problems.

Korean Registered Patent Publication No. 10-0340264 (May 29, 2002) Korean Registered Utility Model Registration No. 20-0272728 (2002. 04. 08.) Korean Registered Utility Model Registration No. 20-0279096 (2002. 06. 07.) Korean Unexamined Patent Publication No. 10-2005-0072860 (Jul. 12, 2005)

The object of the present invention is to solve the above-mentioned problems, and it is an object of the present invention to provide a method and apparatus for recovering organic sludge by using heat generated by burning a dry gas obtained by pyrolysis of municipal waste and industrial waste, Thereby making it possible to obtain a high-quality fuel with a high calorific value, thereby recycling waste resources as high-calorific fuel of high calorific value.

Another object of the present invention is to provide a sludge treatment method and a sludge treatment method which can prevent the coagulation force by using wood, rice husk and lignite powder as auxiliary agents without using any molding agent or adhesive agent for various organic sludge such as municipal waste or industrial waste, It prevents the emission of harmful components and improves the formability by adding wood powder, rice husk and lignite powder which is not a chemical molding agent or adhesive to the organic sludge having an average value of water content of 60 to 80 wt% At the same time, it is eco-friendly to suppress the odor of the sludge itself, to increase the heating value when it is used as fuel, to increase the drying efficiency and to decrease the water content of the sludge.

It is an object of the present invention to provide a method for producing solidified fuel of organic sludge, comprising: a pyrolysis step of generating combustible dry gas obtained by pyrolyzing industrial waste and municipal waste; A combustion process for combusting the combustible dry gas; An energy recovery step of recovering the high-temperature thermal energy generated during the combustion by the boiler and supplying the heat to the dryer; Mixing the organic sludge with an auxiliary agent in an amount of 1 to 15 wt% based on the sludge to form a sludge mixture; An injection molding process for making the sludge mixture prepared by mixing the auxiliary agent and the organic sludge by the mixture manufacturing process have a predetermined shape and shape; To ensure _{that: (low calorific power H L)} 3,000~3,500kcal / kg, on a dry basis 40~45wt% carbon content, was dried at the drier the injection of water in the sludge mixture is obtained by a molding process 10wt% or less, lower heating value Wherein the organic sludge is produced by a calorimetric process of adjusting the amount of the organic sludge.

Wherein the adjuvant is any one of wood, rice hull and lignite powder or a mixture thereof.

Wherein the organic sludge is one of sewage sludge, fowl, and gravel.

The dried sludge mixture of carbon (C) and hydrogen containing itself (H ₂₎ and oxygen (O ₂₎ the reaction and to react with oxygen supplied in small amounts (combustion), low - to ensure that a 70wt% carbon component calorific value H _L 5,000 kcal / kg or more. The present invention is also directed to a method for producing a solidified fuel of an organic sludge.

In the present invention, steam is recovered from the boiler using the energy generated by combustion of the dry gas obtained by pyrolyzing municipal wastes and industrial wastes, and the organic sludge is dried and carbonized by using the remaining high temperature heat, Of the high-quality fuel of the solidified fuel, so that the waste material can be recycled as the solidified fuel.

1 is a manufacturing process diagram showing a method of manufacturing a solidified fuel using an organic sludge to which the technology of the present invention is applied.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. 1 is a schematic diagram showing a method of manufacturing a solidified fuel using an organic sludge according to an embodiment of the present invention. Referring to FIG. 1, a pyrolysis process (S100) for obtaining a combustible dry gas obtained by pyrolyzing industrial wastes, municipal wastes, .

In the pyrolysis process (S100), industrial and municipal wastes are put into a dry gas generator and ignited and burned by an ignition means (refer to a combustion process (S200)), a combustion (oxidation) reaction occurs primarily at 300 to 400 캜 (CO), hydrogen (H ₂ ), and methane (CH ₄ ) are combusted and discharged through the discharge pipe, the present invention is applied to a Korean patent A combustion process (S200) is carried out by burning through a combustor as described in JP-A-2014-0131484.

More specifically, the pyrolysis process (S100) will be described. When the oxidation reaction and the substitution reaction occur simultaneously at the time of pyrolysis, the reaction is as follows.

<Oxidation reaction>

C + O _{2 -} &gt; CO ₂

H ₂ + 1 / 2O _{2 -} &gt; H ₂ O

CH ₄ + 2O ₂ ? CO ₂ + 2H ₂ O

<Substitution reaction>

CO ₂ + C 2CO

H ₂ O + C? CO + H ₂

In the combustion process (S200), the temperature of the combustor generated during the combustion process is 850 to 1,100 ° C. More specifically, the following reactions occur.

<Combustion reaction>

CO + 1 / 2O _{2 -} &gt; CO ₂

_{H2 + 1 / 2O 2 → H} 2 O

The heat generated by the combustion can be recovered from the boiler and used for steam power generation, building heating, hot water supply, and heating of vinyl houses.

On the other hand, the steam recovered from the boiler is reused for other purposes, and the remaining dry gas is delivered to the dryer, and the temperature transferred to the dryer is in the range of 200 to 300 ° C. The heat generated by the combustion of the dry- And the energy recovery process (S300) is performed so that each of them can be used for different purposes.

Typically, the organic sludge has a water content of 60 to 80 wt%, which is excessively contained in the water, thereby drying or dehydrating the sludge. Examples of the organic sludge include sewage sludge, paper mill wastewater sludge, food factory wastewater sludge, Can be used.

Since the organic sludge has a strong cohesive force, it is difficult to perform injection molding to have an arbitrary shape. Therefore, it is necessary to mix the adjuvant to suppress the cohesive force and prepare the mixture so that the molding can be smoothly performed. The sludge of the organic sludge has a water content of about 70 wt%, and when the adjuvant is mixed with 1 to 15 wt% of the sludge, the sludge mixture can be easily shaped into a certain shape. At this time, the water content is slightly reduced. do.

The reason for using the adjuvant is that C, H, and O mixed in the adjuvant are generated as H ₂ O and CO ₂ gas by combustion reaction with the sewage sludge and are discharged, and the gas is discharged by the gas discharged, It is possible to form a solid fuel having a good combustion state because it forms a high porosity in the product.

When the blending amount of sawdust (wood powder), rice hull, lignite powder or a mixture thereof used as the auxiliary agent is less than 1 wt% based on the slurry, the cohesive force may be weakened and the porosity may be lowered to cause a poor combustion state. If it is mixed more than 15wt% with respect to the slurry, the overall cost rise and moisture will be extreme, which may cause difficulty in molding force.

An injection molding process (S500) is performed in which the auxiliary material and the organic sludge are mixed by the mixture manufacturing process (S400) so that the sludge mixture has a certain shape and shape.

In the method of performing the injection molding process (S500), when a sludge mixture is fed to an extruder and then extruded, a cutting blade is placed on the front end of the extruder when the extruder is extruded like a rice cake, and the sludge mixture discharged from the extruder is extruded to a diameter of 5 to 20 mm And a length of 5 to 20 mm is cut to obtain a cylindrical molded body.

The injection molding process is performed in a dryer, preferably at an injection temperature of 250 ° C or higher and at a drying temperature of 150-200 ° C. The sludge mixture dried in the drying method should have a moisture content of 10 wt% or less, a low calorific value H _{L of} 3,000 kcal / kg or more, and a carbon content of 40 wt% or more. .

More specifically, the sludge mixture obtained by the injection molding process (S500) is supplied to a dryer supplied with thermal energy obtained by burning pyrolysis gas of industrial and municipal wastes, so that the sludge mixture contains 10 wt% or less of moisture, 3,500 kcal / kg, and the carbon content is adjusted to 40 to 45 wt% on a dry basis (S600).

The dried solid fuel is subjected to a carbonization process (S700) to produce a porous fuel having a carbon content of 70 wt% or more and a low calorific value H _{L of} 5,000 kcal / kg or more. The dust and odor generated when the municipal waste or the industrial waste is pyrolyzed and burned are generated by the dust filter bag filter and the harmful gas removing device (semi-dry scrubber, wet scrubber) Lt; / RTI &gt; In this case, powdered activated carbon is injected into a non-pacrage scrubber to completely remove trace amounts of heavy metals and dioxins. The neutralization reaction is as follows

<Neutralization reaction>

2HCl + Ca (OH) _{2 -} &gt; CaCl ₂ + 2H ₂ O

SO ₃ + Ca (OH) _{2 -} &gt; CaSO ₄ + 2H ₂ O

Carbonization technology burns hydrogen (H ₂ ) atoms by oxygen (O ₂ ) molecules contained in the raw material and oxygen (O ₂ ) molecules in a small amount of supply air by partially burning the dried raw material at low temperature in a low oxygen state (Oxidation) reaction, and the carbon atoms regulate the supply amount of the supply air so that the carbonization temperature is maintained only by carbon (C) and ash (Ash) by self-combustion (oxidation) reaction. Therefore, no additional fuel is required and the calorific value of the carbonized solid fuel is determined according to the content of the carbon (C) component.

Meanwhile, a carbonization process (S700) is performed in order to form a higher amount of heat of the sludge mixture subjected to the calorific value adjustment process (S600), and the carbonization process (S700) carries out the carbonization process of the dried sludge mixture using a rotary kiln The lower calorific value (H _L ) (S700), the carbon contained in the sludge mixture itself reacts with hydrogen and oxygen, and reacts with oxygen supplied in a small amount, so that a carbon component of 70 wt% or more and a reaction For 60 to 90 minutes at a heating temperature of 250 to 450 DEG C, so that the carbon content is adjusted to 70 wt% of the total weight of one injection-molded sludge mixture.

When the carbonization temperature is high, the yield is low but the carbon content is increased to produce a high-carbon solid fuel having a high heating amount. When the carbonization temperature is low, the carbonization time is increased but the yield is increased.

It can be adjusted according to the amount of heating of the solid fuel required depending on the type of organic sludge and the carbon content. When the carbonization temperature is 450 ° C or higher, a rapid combustion reaction occurs, leading to a decrease in the yield.

S100: Pyrolysis process
S200: Combustion process
S300: Energy recovery process
S400: Mixture manufacturing process
S500: injection molding process
S600: Calorie control process
S700: Carbonization process

Claims (4)

A method for producing solidified fuel of organic sludge,
A pyrolysis process for generating a combustible dry gas obtained by pyrolyzing industrial wastes and municipal wastes;
A combustion process for combusting the combustible dry gas;
An energy recovery step of recovering heat energy generated in the combustion of the carbon monoxide gas by the steam in the boiler and supplying the heat to the drier;
Preparing a sludge mixture by mixing an organic sludge with an auxiliary agent for inhibiting flocculation in an amount of 1 to 15 wt% based on the sludge;
An injection molding process for molding the sludge mixture produced by the mixture manufacturing process so as to have a certain shape and shape;
A calorie regulating step of regulating the calorific value of the molded body by drying in the dryer such that the molded body formed by the injection molding process has a moisture content of 10 wt% or less, a low calorific value of 3,000 to 3,500 kcal / kg, and a carbon content of 40 to 45 wt% The method of manufacturing a solidified fuel molding according to claim 1,
delete The method according to claim 1,
Further comprising a carbonization step of carbonizing a part of the molded body having a calorific value controlled in the calorie regulating step. The method for producing a solidified fuel shaped body according to claim 1,
The method according to claim 1,
Wherein the adjuvant is any one of wood powder, rice husk, and lignite powder or a mixture thereof. The method for producing a solidified fuel compact according to claim 1,

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