KR20100102569A - Method of transforming combustible wastes into energy fuel and gasification system of combustible wastes - Google Patents

Abstract

PURPOSE: A method for producing energy from combustible waste and a combustible waste gasifier are provided to reduce energy cost for thermally decomposing combustible waste by burning char generated in a process of thermally decomposing combustible waste. CONSTITUTION: A method for producing energy from combustible waste comprises following steps. A combustible waste is selected and separated(S100). The combustible waste is put into a closed rotary kiln-type furnace. The combustible waste is thermally decomposed by indirect heating so that pyrolysis synthetic gas may be synthesized. The combustible waste is heated and thermally decomposed over 800°C. The pyrolysis synthetic gas is refined(S300).

Description

Method of transforming combustible wastes into energy fuel and gasification system of combustible wastes

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for energyized recycling of waste, and more particularly to a method for energy fueling flammable waste and a gasification apparatus for flammable waste.

As of 2006, the amount of daily waste generated in Korea was about 318,928 tons, and it has been gradually increasing since 2000. Among these wastes, the recycling rate is about 83.6%, landfill about 8.0%, incineration about 5.4%, and marine emissions. It is processed at a rate of 3.0%. As such, emissions of household waste and industrial waste continue to increase, but conventional waste treatment methods have been continuously raised due to the limitation of landfill and the strengthening of marine emission standards, and various methods such as conversion of waste into energy sources. Is being sought.

In particular, the reliance on fossil fuels such as petroleum, coal, and natural gas, which are the primary energy sources, has reached about 80% or more worldwide. It is estimated that it is about 46 years, natural gas about 67 years, coal about 164 years, and uranium about 85 years. Therefore, the development of alternative energy sources that can cope with such depletion of primary energy sources in the future is urgently required.

Therefore, various ways of using waste as a new energy source have been sought.

The waste can be used as an energy source by using organic waste such as food waste, livestock manure and sewage sludge, using bio-alcohol and biomethane using biogas, and woody biomass and other biomass. Biogas power generation, solid fuelization technology, and bioalcohol production technology, etc., and the method of effectively utilizing the heat generated by incineration of flammable waste, and fueling combustible waste as fuel for power generation energy. Various methods are being studied.

Among the developed countries, active research on the method of fueling combustible wastes as a fuel for generating energy has been conducted in advanced countries, but the present proposal and verification of integrated and universal technologies have not been made yet.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described needs, and an object of the present invention is to provide an integrated method and apparatus capable of fueling combustible wastes and using them as fuel for power generation energy.

In particular, it is an object of the present invention to provide a method and apparatus capable of efficiently utilizing energy input to a method of energy fueling combustible waste.

That is, according to the present invention, the carbides generated in the process of pyrolyzing the combustible waste, ie, char, are burned and reused to pyroly combust the combustible waste, thereby reducing the energy cost of pyrolyzing the combustible waste and thermally decomposing the combustible waste. It is an object of the present invention to provide an energy fueling method of a flammable waste and a gasification apparatus of a flammable waste, which can use the generated combustible gas as another energy source to maximize energy efficiency.

An energy fueling method for combustible wastes according to the present invention for realizing the above object comprises a combustible waste sorting separation process for sorting and separating combustible wastes from wastes; A gasification process of synthesizing pyrolysis syngas by pyrolyzing and combusting the combustible waste obtained in the combustible waste sorting process by an indirect heating method using a rotary kiln type heating furnace; And a gas purification process for purifying the pyrolysis synthesis gas obtained in the gasification process, wherein the pyrolysis synthesis gas obtained in the gas purification process includes 20 to 30% by volume of hydrogen (H ₂ ), 25 to 40% by volume of carbon monoxide (CO) and methane. (CH ₄ ) It is characterized by including 5 to 10% by volume.

Only combustible wastes should be sorted by separating non-combustible and combustible wastes from wastes containing a large number of materials such as household wastes and industrial wastes.

The preferred method of screening only flammable waste is as follows.

The combustible waste sorting process includes a shredding step of crushing the waste to an appropriate size, a metallic material sorting step of separating and separating the metallic material among the shredding wastes obtained in the shredding step by magnetic force, and a shredding waste obtained in the metallic material sorting step. Size separation step to separate the size by size, the weight separation step of separating each size waste by weight using the wind separation, and the fine grinding step of grinding the final separated combustible waste to 20 ~ 40 mm It may include.

The collected waste contains many different types of substances, and their sizes are widely distributed, so it is necessary to crush them to a suitable size for the convenience of the post process. At this time, it is preferable that the appropriate crush size be 50 to 200 mm.

In addition, since the metallic material is mainly a non-combustible material, any of the metallic materials that can be separated by magnetic force can be easily separated out using magnetic force.

In addition, by separating the crushed waste obtained in the step of sorting the metallic material by size, by separating the waste classified by each size by weight using wind power, the waste classified mainly heavy group is classified as incombustible waste, mainly light group Waste classified as is classified as combustible waste. At this time, the separation by size is preferably used to separate the crushed waste by size using a Trommel sorter.

The combustible waste separated and separated as described above is used as a raw material for the gasification process, which is a post process, and the combustible waste is finely ground to improve the efficiency of the gasification process. At this time, by using the final separated combustible waste finely pulverized to 20 ~ 40 mm it is possible to greatly improve the efficiency of the gasification process is a post-process.

Next, by converting the combustible waste into a fuel of power generation energy with high efficiency by going through a gasification process of pyrolyzing and gasifying the combustible waste obtained in the combustible waste sorting separation process.

The combustible wastes are mostly composed of carbon (C) compounds and contain some nitrogen (N), oxygen (O), hydrogen (H) compounds and the like. In case of incineration under the supply of air or oxygen by the combustion method, mainly carbon dioxide (CO ₂ ) is generated, which is a major cause of global warming, which cannot be used as fuel for generating energy.

Therefore, combustible wastes containing mainly carbon compounds (CHO) and some nitrogen compounds (NHO) and water contained in combustible wastes are thermally decomposed by heating under lean oxygen conditions without supply of air (oxygen). It can be synthesized with a flammable pyrolysis synthesis gas containing hydrogen (H ₂ ), carbon monoxide (CO), methane (CH ₄ ), and the like. Then, the synthesized pyrolysis synthesis gas can be used as fuel for power generation energy.

At this time, the gasification process is preferably injected into the combustible waste, it is preferable to thermally decompose to a temperature of about 800 ℃ or more in a sealed device that does not add air.

The gasification reaction for synthesizing the pyrolysis synthesis gas through this gasification process can be represented by the following formula.

<Formula>

That is, the injected flammable waste and lean oxygen, steam, and the like are thermally decomposed at high temperatures, and react with each other through the above chemical reactions, such as H ₂ , CO, H ₂ O, CO ₂ CH ₄ , H ₂ S, N ₂ , NH ₃ , pyrolysis synthesis gas containing HCN and the like and contamination by-products such as ash, slag, tar, dust, acid gas (SOx, HCl) are obtained.

The pyrolysis synthesis gas thus obtained is mainly composed of 20 to 30% by volume of hydrogen (H ₂ ), 25 to 40% by volume of carbon monoxide (CO), and 5 to 10% by volume of methane (CH ₄ ) to be used as fuel for power generation energy. When the power generation efficiency can be greatly increased.

The pyrolysis synthesis gas is carried out by performing a gas purification process to purify contaminant by-products such as ash, slag, tar, dust, and acid gases (SOx, HCl) contained in the pyrolysis synthesis gas thus obtained. Can further improve the power generation efficiency as a power generation fuel.

In particular, the gasification process, the combustible waste input step of injecting the combustible waste into the rotary kiln type furnace; A first heating step of thermally decomposing the combustible waste introduced into the rotary kiln type furnace by using heat generated using externally provided energy; And a second heating step of pyrolyzing the combustible waste by heating the rotary kiln type furnace with heat generated by burning the char generated as a by-product after pyrolyzing the combustible waste by gasification. After the gasification process is started by the secondary heating step, the secondary heating step may be performed at the same time as the secondary heating step or not to be performed after the secondary heating step is performed.

At this time, in the second heating step, when burning char, it is preferable to inject and burn external air heat-exchanged with the high temperature char combustion gas discharged after the rotary kiln heating furnace is heated to the char combustion chamber. Do.

In addition, an energy fueling method for combustible wastes according to the present invention for realizing the above object is a combustible waste sorting separation step of selecting and separating the combustible wastes from the waste; Including the gasification process of synthesizing pyrolysis synthesis gas by pyrolyzing the combustible waste obtained in the combustible waste sorting separation process using a heating furnace, the gasification process is a combustible waste input step of introducing the combustible waste into the heating furnace. Wow; A first heating step of pyrolyzing the combustible waste introduced into the heating furnace by using heat generated by using externally provided energy; A second heating step of thermally decomposing the combustible waste by heating the furnace with heat generated at this time by burning char generated as a by-product after pyrolyzing the combustible waste by gasification, and heating the first furnace After the gasification process is started by the step, after the second heating step is performed, the first heating step may be performed simultaneously with the second heating step, or may not be performed.

In this case, when the char is combusted in the second heating step, it is preferable to inject and burn the external air heat-exchanged with the high temperature char combustion gas discharged after the heating furnace is heated to the char combustion chamber for combustion. .

Gasification apparatus of a flammable waste according to the present invention for realizing the above method, rotary kiln type furnace for synthesizing and discharging the pyrolysis synthesis gas by injecting the flammable waste and pyrolysis by gas indirect heating method; Char combustion which receives char which is a by-product generated in the process of pyrolyzing flammable waste from the rotary kiln type furnace, and burns this char to supply combustion gas to the rotary kiln type furnace to pyroly decompose flammable waste. It is characterized by including a furnace.

The gasification apparatus of the combustible waste is preferably configured to include a primary heater for heating the rotary kiln type furnace using energy provided from the outside.

The rotary kiln heating furnace is composed of a double structure of the outer cylinder and the inner cylinder, it is preferable that the combustion gas provided in the char combustion furnace is configured to heat the inner cylinder while passing between the outer cylinder and the inner cylinder.

At this time, it is preferable that the inner cylinder is rotatably supported inside the outer cylinder.

The rotary kiln type heating furnace is provided with a char-heat inlet through which char combustion gas supplied from the char combustion furnace is introduced in the front portion of the outer cylinder with respect to the flammable waste traveling direction, and the rotary kiln type furnace at the rear portion of the outer cylinder. An outlet for discharging char combustion gas that has been heated may be located.

And a heat exchanger installed on a pipeline for supplying external air to the char combustion furnace to heat the rotary kiln type heating furnace and heat the external air by using the discharged char combustion gas. .

The energy fuelization method of the combustible waste and the gasification apparatus of the combustible waste according to the present invention has the effect that can be used as a fuel for generating energy by fueling the combustible waste.

In particular, the present invention has the effect of efficiently utilizing the energy input to the method of energy fueling the combustible waste.

That is, according to the present invention, the carbide generated during the pyrolysis of the combustible waste, that is, char is burned and reused as an energy source for pyrolyzing the combustible waste, thereby reducing the energy cost of pyrolyzing the combustible waste and combustible waste. The pyrolysis synthesis gas generated by pyrolysis can be used as another energy source, thereby maximizing energy efficiency.

1 is an overall process diagram of an energy fueling method of a combustible waste according to an embodiment of the present invention.
2 is a detailed process diagram of the combustible waste sorting separation process of the energy fuelization method of the combustible waste according to an embodiment of the present invention.
3 is a detailed process diagram of a gasification process of the energy fuelization method of the combustible waste according to an embodiment of the present invention.
4 is a block diagram showing a flammable waste gasification apparatus according to an embodiment of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, the specific form which can implement this invention is demonstrated in detail with reference to drawings. Figure 1 shows the overall process of the energy fueling method of combustible wastes according to the present invention, Figure 2 shows a detailed process of the combustible waste sorting separation process. And Figure 3 shows a detailed process diagram of the gasification process, Figure 4 is a block diagram showing a flammable waste gasification apparatus of the present invention for performing this.

First, a flammable waste sorting separation process (S100) for separating only non-flammable waste and combustible waste from waste is performed. The detailed process is performed as shown in FIG.

That is, as a shredding step (S110), the waste is ground to a size of 50 ~ 200 mm using a general waste shredding device.

In addition, the metallic material in the crushed waste obtained in the crushing step as the metallic material sorting step (S120) is separated out through a magnetic sorting machine.

In this way, the separation of the metal material by side separation and the remaining waste is separated through the trommel sorter to separate the size of the three stages by size of more than 100mm, size of 40 ~ 100mm and size of less than 40mm by three stages. .

Then, to separate the waste separated by the size of the three stages by weight using a wind power unit to perform the separation step by weight 140. In other words, wind turbines are used to separate parts separated into combustible wastes, which are mainly separated into light clusters.

The finely divided combustible waste is finely pulverized to a size of 20 to 40 mm (S150).

Next, gasification of synthesizing pyrolysis synthesis gas by pyrolyzing and combusting the combustible waste obtained in the combustible waste sorting separation process (S100) by an indirect heating method using a rotary kiln type heating furnace 20 as shown in FIG. The process (S200) is performed.

That is, the gasification process (S200) is about 1 at a temperature of about 800 ° C. while stirring the combustible wastes that are selectively separated into the heating furnace, that is, the rotary kiln type heating furnace 20, without the inflow of air from the outside. The pyrolysis synthesis gas is synthesized by pyrolysis for time.

3 and 4, the gasification process (S200), the combustible waste input step of injecting the combustible waste separated by the sorting through the combustible waste sorting separation process (S100) to the rotary kiln type heating furnace 20 (S210). ).

Then, the first heating step (S220) for heating the combustible waste introduced into the rotary kiln type heating furnace 20 using the heat generated by using the external energy provided. At this time, the externally provided energy may use fossil fuels that are generally widely used, such as LPG and diesel. Of course, it is also possible to use other energy to generate electrical energy or other heat.

And a second heating step of heating the combustible waste by injecting the heat generated by burning the char (char) generated as a by-product after the pyrolysis of the combustible waste by gasification (20) ( S230).

In this case, after the gasification process is started by the first heating step S220, after the second heating step S230 is performed, the first heating step S220 is performed in the second heating step. At the same time as (S230) or may not be performed.

In addition, in the second heating step S230, when burning char, the char combustion chamber 40 exchanges preheated external air with heat exchanged with the high-temperature exhaust gas discharged from the rotary kiln type heating furnace 20. It is injected into and burned.

Unlike the above, the second heating step may be performed immediately in a state in which the first heating step S220 is not performed. Of course, preferably, the first heating step and the second heating step are sequentially performed.

The gasification apparatus according to the present invention for performing the gasification process (S200) as described above will be described in detail below with reference to FIG. 4, and the gas purification process (S300) will be briefly described.

 Performing a gas purification step (S300) for purifying contaminant by-products such as ash, slag, tar, dust, and the like contained in the pyrolysis synthesis gas obtained through the gasification process (S200). Finally, pyrolysis synthesis gas can be obtained.

The results of analyzing the components and component ratios of the pyrolysis synthesis gas thus obtained are shown in Table 1 below. The components and the component ratios of the pyrolysis syngas were measured using gas chromatography.

ingredient Component ratio (% by volume) H ₂ 20.5 CO 26.1 CO ₂ 19.8 C ₂ H ₄ 12.9 CH ₄ 7.2 N ₂ 5.6 C ₂ H ₆ 4.1 O ₂ 1.1 Etc 2.7

In other words, it can be seen that the pyrolysis synthesis gas thus obtained comprises 20 to 30% by volume of hydrogen (H ₂ ), 25 to 40% by volume of carbon monoxide (CO) and 5 to 10% by volume of methane (CH ₄ ). .

Now, the gasification apparatus of the combustible waste according to the present invention mentioned above will be described in detail.

The gasification apparatus of the combustible waste of the present invention, referring to Figure 4, waste storage tank 10, rotary kiln type heating furnace 20, char combustion furnace 40, heat exchanger 50, gas purification device 30 It consists of, etc., each configuration will be described in detail.

First, the waste storage tank 10, the combustible waste sorted through the above-described flammable waste sorting separation process (S100) is stored. Of course, the waste storage tank 10 may be configured to input the waste before the screening separation, in the process of supplying to the rotary kiln-type heating furnace 20, the combustible waste screening separation process (S100).

Reference numeral 12 denotes a conduit for supplying combustible waste to the rotary kiln type furnace 20 in the waste storage tank 10, 14 is a screw device for transporting combustible waste, and FIG. 16 shows a rotary kiln type furnace for combustible waste. (20) The feeder to be introduced into the inside is shown. At this time, the feeder 16 is preferably configured to supply a combustible waste to the rotary kiln type heating furnace 20 at regular intervals, and also serves to block the inlet of the rotary kiln type heating furnace 20 at the same time.

Next, the rotary kiln type heating furnace 20 is configured to synthesize and discharge the pyrolysis synthesis gas by pyrolyzing and combusting the combustible waste supplied from the waste storage tank 10 by indirect heating.

The rotary kiln type heating furnace 20 is composed of a double structure consisting of the outer cylinder 21 and the inner cylinder 22, the inner cylinder 22 so that the combustible waste can be thermally decomposed while the inside is sealed. The outer cylinder 21 supports the inner cylinder 22 so as to be rotatable therein, and is also heated by the primary heater 23 to be described later, or char combustion gas is formed between the inner cylinder 22 and the outer cylinder 21. It is configured to be heated while passing.

Here, the primary heater 23 is a burner device for heating the rotary kiln type heating furnace 20 using energy provided from the outside such as LPG, diesel, and other energy.

Next, the char combustion furnace 40 receives carbide, that is, char, which is a by-product generated in the process of pyrolyzing combustible waste from the rotary kiln type heating furnace 20, and burns the char to generate the char. It is configured to provide a combustion gas to the space between the inner cylinder 22 and the outer cylinder 21 of the rotary kiln type heating furnace 20 to thermally decompose the combustible waste passing through the inner cylinder 22. .

The char combustion furnace 40 is connected via the rotary kiln type heating furnace 20 and the char supply pipe 42, and the char injector 45 operated by the hydraulic device 44 or the like on the char supply pipe 42. Is provided. Reference numeral 41 denotes a char transfer device for forcibly transferring the char discharged from the rotary kiln type heating furnace 20 using a screw or the like.

In addition, the char combustion furnace 40 is provided with a burner 46 for burning char in the inside thereof, and a combustion residue discharge portion 47 is provided at the bottom to burn the char and discharge the remaining ash. The upper one side is connected to the char combustion gas supply pipe 48 for supplying the combustion gas (exhaust gas) generated while the char is burned into the outer cylinder 21 of the rotary kiln type heating furnace 20.

The char combustion furnace 40 is required to supply oxygen to burn the char, and is configured such that external air preheated to about 150 ° C to 300 ° C is introduced while passing through the heat exchanger 50. As the air preheated to a high temperature while passing through the heat exchanger 50 is introduced into the char combustion furnace 40, the char is burned more efficiently, using less energy, and the char combustion gas of about 800 ° C. is rotary kiln type. The heating furnace 20 may be provided to pyrolyze the combustible waste.

The heat exchanger 50 is installed on an external air supply pipe 51 for supplying external air to the char combustion furnace 40, and the exhaust gas pipe in the outer cylinder 21 of the rotary kiln type heating furnace 20. It is configured to heat the outside air by using the char combustion gas discharged through 53).

Reference numeral 55 denotes a pressurized blower for supplying combustion air to the heat exchanger 50 and the char combustion furnace 40, and reference numeral 56 denotes a char combustion gas (exhaust gas) heating the rotary kiln type heating furnace 20. Induced drawer blower for forced discharge. And reference numeral 57 denotes a stack to discharge char combustion gas outside.

In the rotary kiln type heating furnace 20, the char supply pipe 48 is connected so that the char combustion heat provided from the char combustion furnace 40 is introduced into the front portion of the outer cylinder 21 with respect to the flammable waste traveling direction. Char heat inlet 49 is disposed, it is preferably made of a configuration in which the discharge port 52 is connected to the exhaust gas pipe 53 is located in the rear portion of the outer cylinder (21).

As a result, in the rotary kiln type heating furnace 20 as described above, when the combustible waste moves while passing through the inner cylinder 22, the outer cylinder 21 is primarily heated by the primary heater 23. And pyrolysis of the combustible waste passing through the inner cylinder 22 by indirect heating, and secondly, the combustion gas generated by burning the char in the process of pyrolyzing the combustible waste, that is, char in the char combustion furnace 40. The exhaust gas is passed through the space between the outer cylinder 21 and the inner cylinder 22 to heat the inner cylinder 22 to thermally decompose the combustible waste.

Next, the gas purification device 30 is ash, slag, tar, dust, acidic gas (SOx) contained in the pyrolysis synthesis gas discharged from the rotary kiln type heating furnace 20. As a device for purifying contaminant by-products such as HCl), it is possible to further improve the power generation efficiency of the pyrolysis synthesis gas as power generation fuel.

In the present invention, as the pyrolysis syngas is not used to heat the rotary kiln type furnace 20 again, the purified gas in the gas purification apparatus 30 can be used as an energy source for generating energy fuel or other uses. It is possible to maximize the energy utilization efficiency than the conventional energy system.

Claims (4)

Flammable waste sorting separation process for sorting and separating combustible wastes from wastes;
The pyrolysis synthesis gas is synthesized by injecting the combustible waste obtained in the combustible waste sorting process into a closed rotary kiln type furnace and pyrolyzing and gasifying by indirect heating method, but does not add air into the rotary kiln type furnace. A gasification step of pyrolyzing the combustible waste by heating it to a temperature of 800 ° C. or higher in a non-existing state;
And a gas purification step of purifying the pyrolysis synthesis gas obtained in the gasification step.
The method of claim 1,
The pyrolysis synthesis gas obtained in the gas purification process comprises 20 to 30% by volume of hydrogen (H ₂ ), 25 to 40% by volume of carbon monoxide (CO) and 5 to 10% by volume of methane (CH ₄ ). Method of energy fueling flammable waste.
The method according to claim 1 or 2,
The gasification process includes a combustible waste input step of injecting the combustible waste into the rotary kiln type heating furnace;
A first heating step of thermally decomposing the combustible waste introduced into the rotary kiln type furnace by using heat generated using externally provided energy;
And a second heating step of thermally decomposing the combustible waste by heating the rotary kiln type furnace with heat generated by burning the char generated as a by-product after pyrolyzing the combustible waste by gasification,
After the gasification process is started by the first heating step, after the second heating step is performed, the first heating step is performed simultaneously with the second heating step or not. Method of energy fueling combustible waste.
Flammable waste sorting separation process for sorting and separating combustible wastes from wastes; A gasification process for synthesizing pyrolysis synthesis gas by injecting the flammable waste obtained in the combustible waste sorting separation process into a closed heating furnace and pyrolyzing and combusting the combustible waste by indirect heating in a state where no air is introduced into the heating furnace. Including,
The gasification process includes a combustible waste input step of injecting the combustible waste into the heating furnace; A first heating step of pyrolyzing the combustible waste introduced into the heating furnace by using heat generated by using externally provided energy; And a second heating step of thermally decomposing the combustible waste by pyrolyzing the combustible waste and gasifying and burning char generated as a by-product and heating the furnace with heat generated at this time.
After the gasification process is started by the first heating step, after the second heating step is performed, the first heating step is performed simultaneously with the second heating step or not. Method of energy fueling combustible waste.

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