CN105737162A - Household garbage low-temperature pyrolysis system and method based on process decoupling and scrubbing combustion - Google Patents

Abstract

The invention discloses a low-temperature pyrolysis system and method for household garbage based on process decoupling and gas scrubbing and combustion. The household garbage is first sent to a drying drum for drying, and then sent to a pyrolysis drum for pyrolysis to generate pyrolysis gas and carbon slag, which are then dried. And pyrolysis is divided into start-up stage and normal operation stage. In the start-up stage, the gas output from the air and gas storage is mixed and passed through the burners of the drying drum and the pyrolysis drum to burn in the cavities of the drying drum and the pyrolysis drum to provide heat. Generate high-temperature flue gas; during normal operation, the high-temperature flue gas in the cavity of the pyrolysis drum is sent to the cavity of the drying drum for heat exchange and drying, and the burner of the drying drum becomes an auxiliary heat source; the pyrolysis gas passes through the moving bed adsorption device, The plasma scrubber and the moving bed absorption device are used for purification, and the flue gas and pyrolysis gas are finally recovered in the gas and flue gas waste heat heat exchanger. The invention makes full use of the waste heat to produce high-temperature steam, and the flue gas is discharged after being cooled and purified, effectively controlling the generation of dioxins, and realizing resource utilization, reduction and low-carbonization of domestic garbage.

Description

Low-temperature pyrolysis system and method for domestic waste based on process decoupling and scrubbing combustion

technical field

The invention relates to the harmless treatment of household garbage and its resource recycling technology, in particular to a low-temperature pyrolysis system and method for household garbage based on process decoupling and scrubbing combustion.

Background technique

Now, my country produces more than 200 million tons of municipal solid waste every year, and the annual growth rate of waste has reached more than 10%. In recent years, although some achievements have been made in the treatment of domestic waste in my country, the overall capacity is still obviously insufficient. The growth rate of waste treatment capacity obviously lags behind the growth rate of waste generation. The suburbs have occupied a large area of land, and some cities are already facing the threat of "garbage siege".

At present, there are three main methods of municipal solid waste treatment widely used in my country and even in the world, including landfill, incineration, and composting. Among them, landfill is the main way to deal with municipal solid waste in my country, and the amount of waste treated accounts for about 10% of the total amount of waste. 80%. However, the landfill treatment method has disadvantages such as occupying a large amount of land resources, polluting leachate, and methane gas produced by fermentation intensifying the greenhouse effect. However, the composting method has problems such as a large area, a long conversion process, difficult to stabilize the state, and difficult to control the product quality. At the same time, the waste treated by composting in my country is basically mixed waste, which has not been strictly classified, so it is inevitable in the composting process. Mixing a large amount of toxic and harmful substances such as heavy metals, coupled with the unorganized emission of methane and other greenhouse gases, can easily cause serious pollution to the surrounding environment. Among the above three methods, the incineration method is the most effective treatment method for waste reduction, which can reduce the volume of waste by 85% and the weight by more than 75%. However, incineration of waste has hidden dangers of environmental pollution, especially the dioxin produced by incineration Ying has irreversible "three-induced" toxicity, which is extremely harmful to human health, and has become the most concerned issue at present. In addition, there are some restrictions on the incineration of waste:

(1) Municipal solid waste in China is basically mixed and collected, with complex components, and incineration generally requires the minimum calorific value of waste to be above 3360kJ·kg ^-1 , when the calorific value of waste is too low, it is necessary to add fuel to assist combustion, so It will cause an increase in operating costs. At present, except for a few economically developed cities in China, garbage sorting and collection in other cities have not been widely carried out, so the calorific value of mixed domestic garbage is low, which is not suitable for incineration;

(2) The investment and operating costs of incineration treatment equipment are relatively high. Most of the waste incineration power plants built in my country in the early stage imported foreign technology and equipment, and the investment cost was expensive. In recent years, with the localization of imported equipment and independent innovation of technology, domestic Technology and equipment have been developed and applied. Although the investment in incineration plant units has decreased, the investment and operating costs of incineration treatment are still high for areas with average economic affordability.

Compared with the incineration method, the more advanced pyrolysis technology is a decomposition reaction carried out in an oxygen-free or hypoxic reducing environment, which not only has the same reduction characteristics as the incineration method, but also produces secondary pollution. There are fewer emission substances, so it has a good application prospect. In addition, pyrolysis technology converts useful substances in waste into gaseous (gas) or liquid (tar) forms for use respectively. These gaseous and liquid fuels are more efficient and less polluting than direct combustion of solid waste. At present, domestic waste pyrolysis treatment technology has been studied to a certain extent, such as the invention patent with the publication number CN103242134A and the name "A Method for Pyrolysis and Gasification Purification of Household Waste". Under certain conditions, oxygen is introduced to carry out combustion and cracking reactions, and the combustible gas generated by the pyrolysis of garbage is used comprehensively to synthesize chemical raw materials to realize the resource utilization of domestic waste. Complicated, so this increases the difficulty of synthesizing chemical raw materials, and the treatment of garbage under high temperature and aerobic conditions, the subsequent purification process costs are high, and the exhaust emissions are also large. Another example is an invention patent with the publication number CN102660306A and the name "Countercurrent Rotary Domestic Garbage Pyrolysis Carbonization Furnace System and Garbage Treatment Process". heat source to achieve waste reduction and recycling, but this process does not dry and pretreat domestic waste, but uses a method of drying while pyrolyzing, which will increase the energy consumption of the system and reduce the processing efficiency. The direct discharge of flue gas after cooling treatment will also have a certain impact on the atmospheric environment, especially in today's society plagued by smog, the follow-up treatment of flue gas cannot be ignored. Therefore, in view of the existing problems in the existing patented technology and its application, it is of great scientific and social and economic significance to further study and improve the waste pyrolysis treatment process, reduce the generation of secondary pollution emissions, and reduce the difficulty of tail gas treatment.

Contents of the invention

The technical problem to be solved by the present invention is to provide a low-temperature pyrolysis system and method for domestic waste based on process decoupling and gas scrubbing combustion, which can reduce the generation of secondary pollution and discharge substances, reduce the difficulty of tail gas treatment, and make full use of the waste produced by the system at the same time. products, reducing energy consumption and improving process efficiency.

In order to solve the above technical problems, the low-temperature pyrolysis system of domestic waste based on process decoupling and scrubbing combustion provided by the present invention includes a feeding device, a pyrolysis section, a scrubbing section and a heat recovery section, wherein the pyrolysis section includes a drying drum And the pyrolysis drum, the scrubbing section includes a moving bed adsorption device, a plasma scrubbing device and a moving bed absorption device, and the heat recovery section includes a flue gas waste heat recovery device and a pyrolysis gas waste heat recovery device;

The drying drum includes a drying drum inner drum, a drying drum outer drum and a drying drum burner, domestic garbage is pushed into the drying drum inner drum by a feeding device; the drying drum inner drum and the drying drum outer drum are sealed structure and a cavity is formed between the two; the rear end of the inner drum of the drying drum is provided with a water vapor outlet and a mixed garbage outlet, and the water vapor outlet is connected with a sewage treatment device; the outer cylinder of the drying drum is provided with a A gas inlet and a flue gas outlet connected to the cavity of the drying drum; the drying drum burner is arranged on the outer wall of the inner drum of the drying drum;

The pyrolysis drum includes the inner drum of the pyrolysis drum, the outer drum of the pyrolysis drum, the burner of the pyrolysis drum and the gas-solid separator, and the garbage discharged from the mixed garbage outlet of the inner drum of the drying drum is pushed in by another feeding device In the inner drum of the pyrolysis drum; the inner drum of the pyrolysis drum and the outer drum of the pyrolysis drum are of a sealed structure and a cavity is formed between the two; the outer drum of the pyrolysis drum is provided with a Connected gas inlet and flue gas outlet, the flue gas outlet communicates with the gas inlet on the outer cylinder of the drying drum, the gas inlet is supplied by air and gas in a gas storage; the pyrolysis drum burner is arranged in the pyrolysis drum On the outer wall of the drum, the gas-solid separator communicates with the rear end of the drum in the pyrolysis drum, and has a pyrolysis gas outlet and a carbon residue outlet, and the carbon residue outlet is connected to a carbon residue collection device;

The moving bed adsorption device, the plasma suction device and the moving bed absorption device all have a gas inlet and a gas outlet, the gas inlet of the moving bed adsorption device communicates with the pyrolysis gas outlet of the gas-solid separator, and the plasma suction device The gas inlet is connected to the gas outlet of the moving bed adsorption device, and the gas outlet of the plasma suction device is connected to the gas inlet of the moving bed absorption device;

The flue gas waste heat recovery device has a high-temperature flue gas inlet, a low-temperature flue gas outlet, a low-temperature medium inlet and a high-temperature medium outlet, and the pyrolysis gas waste heat recovery device includes a high-temperature pyrolysis gas inlet, a low-temperature pyrolysis gas outlet, a low-temperature medium inlet and a high-temperature medium outlet , the high-temperature flue gas inlet of the flue gas waste heat recovery device is connected with the flue gas outlet on the outer cylinder of the drying drum, the low-temperature flue gas outlet is connected with the atmosphere, and the high-temperature pyrolysis gas inlet of the pyrolysis gas waste heat recovery device is connected with the gas of the moving bed absorption device The outlet is connected, the low-temperature pyrolysis gas outlet is connected to the gas storage, the low-temperature medium inlet of the flue gas waste heat recovery device and the pyrolysis gas waste heat recovery device are both connected to the lower water outlet of a high-temperature steam storage, the flue gas waste heat recovery device and the pyrolysis gas The high-temperature medium outlets of the waste heat recovery device are all in communication with the steam inlets of the high-temperature steam storage.

Further, both the outer surface of the outer cylinder of the drying drum and the outer surface of the outer cylinder of the pyrolysis drum are covered with an insulation layer of 80-120mm aluminum silicate or rock wool.

Wherein, the feeding device includes a garbage feeding bin and a screw propeller, and the screw propeller pushes the garbage in the garbage feeding bin into the inner drum of the drying drum or the inner drum of the pyrolysis drum.

Wherein, the moving bed adsorption device is filled with quicklime for removing heavy metals and acidic substances in the pyrolysis gas; the plasma scrubbing device includes six-stage plasma generators connected in series for removing PM substances and tar; the moving bed absorption device is filled with basic catalysts (mainly containing dolomite) for removing sulfur-containing compounds and chlorine-containing compounds in the pyrolysis gas.

Preferably, the pyrolysis drum burners are evenly distributed on the outer wall of the inner drum of the pyrolysis drum located in the outer drum of the pyrolysis drum.

Wherein, both the flue gas waste heat recovery device and the pyrolysis gas waste heat recovery device are heat pipe heat exchangers.

Further, the inner wall of the outer cylinder of the drying drum is provided with a thread structure for guiding flue gas.

The present invention also provides a low-temperature pyrolysis method for domestic waste based on process decoupling and scrubbing combustion, including:

1) The feeding device sends domestic waste into the inner drum of the drying drum for drying treatment, and discharges most of the water in the domestic waste to the sewage treatment device. The drying temperature is controlled at 120°C-200°C, and the drying time is controlled at 0.5h -1h, the speed of the inner drum is controlled at 4-8rpm;

The dried domestic waste is sent to the inner drum of the pyrolysis drum for pyrolysis treatment to generate pyrolysis gas and carbon residue. The pyrolysis temperature is controlled at 400°C-600°C, and the pyrolysis time is controlled at 0.5h-1h. The speed of the inner drum is controlled at 4-8rpm;

The drying treatment and pyrolysis treatment of domestic waste are divided into start-up phase and normal operation phase;

In the start-up phase, the air and the gas output from the gas storage are mixed and then burned in the cavity of the drying drum and the cavity of the pyrolysis drum through the drying drum burner and the pyrolysis drum burner to generate high-temperature flue gas;

After the start-up phase is completed and the normal operation phase is completed, the high-temperature flue gas in the cavity of the pyrolysis drum is transported to the cavity of the drying drum to perform heat exchange and drying on the domestic waste in the drum of the drying drum, and the burner of the drying drum is switched to an auxiliary heat source. After the air and the gas output from the gas storage are mixed, they continue to burn through the pyrolysis drum burner in the cavity of the pyrolysis drum to generate high-temperature flue gas. Water enters the flue gas waste heat recovery device for heat exchange, and the water flowing out from the lower part of the high-temperature steam storage absorbs the heat of the flue gas to form high-temperature steam, which enters the high-temperature steam storage, and the waste heat of the flue gas is absorbed and discharged;

2) The pyrolysis gas is sent to the scrubbing section, and is purified through the moving bed adsorption device, plasma suction device and moving bed absorption device in turn, and the washed pyrolysis gas and the water flowing out of the lower part of the high-temperature steam storage enter the pyrolysis Heat exchange is carried out in the gas waste heat recovery device. The water flowing out from the lower part of the high-temperature steam storage absorbs the heat of the pyrolysis gas to form high-temperature steam and enters the high-temperature steam storage. The pyrolysis gas releases waste heat and enters the gas storage.

Wherein, the moving bed adsorption device is filled with quicklime for removing heavy metals and acidic substances in the pyrolysis gas; the plasma scrubbing device includes six-stage plasma generators connected in series for removing PM substances and tar; the moving bed absorption device is filled with dolomite to remove sulfur-containing compounds and chlorine-containing compounds in pyrolysis gas

The benefits of the present invention are:

1) Using low-temperature pyrolysis technology, domestic waste does not need special sorting before entering the drying drum, and the waste heat of the system (high-temperature flue gas generated by the pyrolysis drum) is used to dry and pretreat the waste before entering the pyrolysis drum. The dried waste contains The water volume is reduced to 40%, which increases the pyrolysis treatment capacity by 50%. At the same time, the drying drum and the pyrolysis drum are made of thermal insulation materials, which effectively reduces heat loss, saves energy consumption, and controls heat loss within 30%;

2) The clean pyrolysis gas provides the combustion medium for the drying drum burner and pyrolysis drum burner in the start-up phase and the pyrolysis drum burner in the normal operation phase in the way of internal recycling and combustion. Multiple burners are arranged to make the inner drum of the pyrolysis drum evenly heated and fully pyrolyzed;

3) The scrubbing section adopts a step-by-step purification process, which successively passes through the quicklime moving bed adsorption device to remove heavy metals and acidic substances, and the plasma scrubbing device to effectively degrade odorous substances, tar and PM substances (including PM _2.5 and PM ₁₀ ), dolomite moving The desulfurization and dechlorination of the bed absorption device finally makes the tar content of the pyrolysis gas less than 1.2%, and the PM discharge meets the standard; the whole system fully recovers waste heat, and finally produces two types of products, clean gas and high-temperature steam, and the clean gas produced completely meets the waste heat. Solve the needs, and the surplus part is output as a product.

Description of drawings

The accompanying drawing is a schematic diagram of the system principle of the present invention.

Wherein the reference signs are explained as follows:

1 is the feeding device; 1-1 is the garbage feeding bin; 1-2 is the screw propeller; 2 is the drying drum; 2-1 is the inner drum of the drying drum; 2-2 is the outer drum of the drying drum; 2-3 3 is the pyrolysis drum; 3-1 is the inner drum of the pyrolysis drum; 3-2 is the outer cylinder of the pyrolysis drum; 3-3 is the pyrolysis drum burner; 3-4 is the gas-solid separation 4 is a moving bed adsorption device; 5 is a plasma scrubber; 5-1 is a plasma generator; 6 is a moving bed absorption device; 7 is a gas waste heat exchanger; 8 is a flue gas waste heat heat exchanger; 9 is a gas storage; 10 is a high-temperature steam storage; 11 is a fan; 12 is a sewage treatment device; 13 is a carbon residue collection device; A is air; F is high-temperature flue gas; S is high-temperature steam products; G is gas products.

detailed description

The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

The domestic waste low-temperature pyrolysis system based on process decoupling and gas scrubbing combustion provided by the present invention, as shown in the accompanying drawings, includes a feeding device, a pyrolysis section, a gas scrubbing section, and a heat recovery section, wherein the pyrolysis section includes a drying drum 2 and the pyrolysis drum 3, the gas scrubbing section includes a moving bed adsorption device 4, a plasma scrubbing device 5 and a moving bed absorption device 6, and the heat recovery section includes a flue gas waste heat recovery device and a pyrolysis gas waste heat recovery device; wherein:

Drying drum 2 includes drying drum inner drum 2-1, drying drum outer drum 2-2 and drying drum burner 2-3; feeding device 1 communicates with drying drum inner drum 2-1; drying drum inner drum 2 -1 and the drying drum outer cylinder 2-2 are sealed structures and a cavity is formed between the two; the rear end of the drying drum inner drum 2-1 is provided with a water vapor outlet and a mixed garbage outlet, and the water vapor outlet is connected to a sewage treatment The device 12 is connected; the outer cylinder 2-2 of the drying drum is provided with a gas inlet and a flue gas outlet communicating with the cavity of the drying drum; the burner 2-3 of the drying drum is arranged on the outer wall of the inner drum 2-1 of the drying drum;

The pyrolysis drum 3 includes a pyrolysis drum inner drum 3-1, a pyrolysis drum outer drum 3-2, a pyrolysis drum burner 3-3 and a gas-solid separator 3-4; the mixing of the drying drum inner drum 2-1 The garbage discharged from the garbage outlet is pushed into the inner drum 3-1 of the pyrolysis drum by a feeding device (not shown in the figure); the inner drum 3-1 of the pyrolysis drum and the outer drum 3-2 of the pyrolysis drum are sealed structure and a cavity is formed between the two; the pyrolysis drum outer cylinder 3-2 is provided with a gas inlet and a flue gas outlet communicating with the pyrolysis drum cavity, and the flue gas outlet is connected to the drying drum outer cylinder 2-2 The gas inlet of the gas inlet is connected, and the gas inlet is supplied to air and the gas in a gas storage 9 to enter; the pyrolysis drum burner 3-3 is arranged on the outer wall of the pyrolysis drum inner drum 3-1, and the gas-solid separator 3 -4 communicates with the rear end of the drum 3-1 in the pyrolysis drum, which has a pyrolysis gas outlet and a charcoal slag outlet, and the charcoal slag outlet is connected to a charcoal slag collecting device 13;

The moving bed adsorption device 4, the plasma suction device 5 and the moving bed adsorption device 6 all have a gas inlet and a gas outlet, and the gas inlet of the moving bed adsorption device 4 communicates with the pyrolysis gas outlet of the gas-solid separator 3-4 , the gas inlet of the plasma suction device 5 communicates with the gas outlet of the moving bed adsorption device 4, and the gas outlet of the plasma suction device 5 communicates with the gas inlet of the moving bed adsorption device 6;

The flue gas waste heat recovery device has a high-temperature flue gas inlet, a low-temperature flue gas outlet, a low-temperature medium inlet and a high-temperature medium outlet, and the pyrolysis gas waste heat recovery device includes a high-temperature pyrolysis gas inlet, a low-temperature pyrolysis gas outlet, a low-temperature medium inlet and a high-temperature medium outlet , the high-temperature flue gas inlet of the flue gas waste heat recovery device communicates with the flue gas outlet on the outer cylinder 2-2 of the drying drum, the low-temperature flue gas outlet communicates with the atmosphere, and the high-temperature pyrolysis gas inlet of the pyrolysis gas waste heat recovery device communicates with the moving bed absorption The gas outlet of the device 6 is connected, the low-temperature pyrolysis gas outlet is connected with the gas storage 9, the low-temperature medium inlet of the flue gas waste heat recovery device and the pyrolysis gas waste heat recovery device are both connected with the lower water outlet of a high-temperature steam storage 10, and the flue gas waste heat Both the high-temperature medium outlets of the recovery device and the pyrolysis gas waste heat recovery device communicate with the steam inlet of the high-temperature steam storage 10 .

The two ends of the inner drum 2-1 of the drying drum extend out of the outer drum 2-2 of the drying drum, and the two ends of the inner drum 3-1 of the pyrolysis drum also extend out of the outer drum 3-2 of the pyrolysis drum. In order to heat the inner drum 3-1 of the pyrolysis drum evenly to achieve sufficient pyrolysis, the burners 3-3 of the pyrolysis drum are evenly distributed in the inner drum 3-1 of the pyrolysis drum located in the outer drum 3-2 of the pyrolysis drum on the outer wall.

In addition, in order to effectively reduce the heat loss of the drying drum 2 and the pyrolysis drum 3, the outer surface of the drying drum outer cylinder 2-2 and the outer surface of the pyrolysis drum outer cylinder 3-2 are covered with 80-120mm aluminum silicate Insulation layer or rock wool insulation layer.

In the above system, the feeding device includes a garbage feeding bin and a screw propeller, and the screw propeller pushes the garbage in the garbage feeding bin into the inner drum of the drying drum.

Among them, the moving bed adsorption device is filled with quicklime, which is used to remove heavy metals and acidic substances in the pyrolysis gas; the plasma scrubbing device includes a series of six-stage plasma generators, which are used to remove PM substances and acid substances in the pyrolysis gas. Tar; the moving bed absorption unit is filled with basic catalysts (mainly composed of dolomite) to remove sulfur compounds and chlorine compounds in the pyrolysis gas.

Preferably, the flue gas waste heat recovery device and the pyrolysis gas waste heat recovery device are heat pipe type gas waste heat heat exchanger 7 and heat pipe type flue gas waste heat heat exchanger 8 respectively.

In addition, the inner wall of the outer cylinder 2-2 of the drying drum is provided with a threaded structure, which can guide the high-temperature flue gas in the cavity of the drying drum to run.

A low-temperature pyrolysis method for domestic waste based on process decoupling and scrubbing combustion using the above system, including:

1) The screw propeller 1-2 in the feeding device 1 sends the domestic garbage in the garbage feeding bin 1-1 to the inner drum 2-1 of the drying drum for drying treatment, and discharges most of the water in the domestic garbage to the sewage Processing device 12, wherein the drying temperature is controlled at 120°C-200°C, the drying time is controlled at 0.5h-1h, and the speed of the inner drum is controlled at 4-8rpm;

The dried domestic waste is sent to the inner drum 3-1 of the pyrolysis drum for pyrolysis treatment, and pyrolysis gas and carbon residue are generated. The pyrolysis temperature is controlled at 400°C-600°C, and the pyrolysis time is controlled at 0.5h- 1h, the rotating speed of the inner drum is controlled at 4-8rpm, and the moisture content of the dried mixed garbage is reduced to 40%;

The drying treatment and pyrolysis treatment of domestic waste are divided into start-up phase and normal operation phase;

In the start-up phase, the air A delivered by the fan 11 and the gas G output from the gas storage 9 are mixed and passed through the drying drum burner 2-3 and the pyrolysis drum burner 3-3 respectively in the drying drum cavity and the pyrolysis drum cavity Combustion heat supply produces high temperature flue gas;

After the start-up phase is completed and enters the normal operation phase, the high-temperature flue gas F in the cavity of the pyrolysis drum is transported to the cavity of the drying drum to perform heat exchange and drying on the domestic garbage in the drum 2-1 in the drying drum, and the drying drum burner 2 -3 is switched to an auxiliary heat source, the air A delivered by the fan 11 is mixed with the gas G output by the gas storage 9, and then continues to burn through the pyrolysis drum burner 3-3 in the cavity of the pyrolysis drum to generate high-temperature flue gas F. The heat-exchanged flue gas in the cavity of the drying drum (the temperature drops to 180°C-200°C) and the water flowing out from the lower part of the high-temperature steam storage 10 (the temperature is about 80°C) enter the flue gas waste heat exchanger 8 for heat exchange. The water flowing out from the lower part of the high-temperature steam storage 10 absorbs the heat of the flue gas to form high-temperature steam and enters the high-temperature steam storage 10. After the waste heat of the flue gas is absorbed, the temperature drops to 105°C and can be discharged directly;

2) The pyrolysis gas is sent to the scrubbing section. The pyrolysis gas first passes through the moving bed adsorption device 4. The quicklime filled inside the device reacts with the high-temperature water vapor carried in the pyrolysis gas to digest the mature lime. On the one hand, a large amount of heat is released. In order to maintain the gas temperature and avoid tar condensation, on the other hand, the specific surface area increases significantly during the process of quicklime digestion of slaked lime, and the surface adsorption capacity is enhanced. It can also effectively remove heavy metal elements such as mercury and Other acidic substances; the pyrolysis gas after preliminary purification enters the plasma scrubbing device 5, which decomposes water molecules to produce highly active hydroxyl groups by generating a plasma field, and the hydroxyl groups make the long-chain tar molecules with complex structures uncracked into simple structures. For short-chain molecules, the six-stage plasma generator 5-1 is connected in series to ensure the removal rate of tar; the purified pyrolysis gas enters the moving bed absorption device 6, and is catalyzed by the basic catalyst in the device to remove, for example, SO ₂ , HCl and other compounds containing sulfur and chlorine;

The washed pyrolysis gas and the water flowing out of the lower part of the high-temperature steam storage 10 enter the gas waste heat exchanger 7 for heat exchange, and the water flowing out of the lower part of the high-temperature steam storage 10 absorbs the heat of the pyrolysis gas to form high-temperature steam and enters the high-temperature steam storage 10 , the pyrolysis gas enters the gas storage 9 after releasing the waste heat;

The high-temperature steam S in the high-temperature steam storage 10 and the surplus gas G in the gas storage 9 are finally output as products.

In the present invention, the domestic garbage is pyrolyzed at low temperature in the pyrolysis drum to generate pyrolysis gas and solid carbon residue, and the gas and solid are separated and processed separately, realizing process decoupling. The pyrolysis gas is partially reused and burned after being purified by the gas scrubbing section, and no secondary pollutants will be generated. Therefore, it is not necessary to spend a lot of effort to treat the tail gas. In this way, a small amount of scrubbing gas before combustion replaces a large amount of scrubbing gas after combustion.

In addition, the present invention adopts low-temperature pyrolysis technology, and domestic waste does not need to be sorted before entering the drying drum, and the waste heat of the system (high-temperature flue gas generated by the pyrolysis drum) is used to dry and pretreat the waste before entering the pyrolysis drum. The water content of the garbage is reduced to 40%, which increases the pyrolysis treatment capacity by 50%. At the same time, the drying drum and the pyrolysis drum are made of thermal insulation materials, which can effectively reduce heat loss, save energy consumption, and control heat loss within 30%.

The scrubbing section adopts a cascade purification process, which successively passes through the quicklime moving bed adsorption device to remove heavy metals and acidic substances, the plasma scrubbing device to effectively degrade odor substances, tar and PM substances (including PM _2.5 and PM ₁₀ ), and the dolomite moving bed absorption The desulfurization and dechlorination of the device finally makes the tar content of the pyrolysis gas less than 1.2%, and the PM discharge meets the standard; the whole system fully recovers waste heat, and finally produces two types of products, clean gas and high-temperature steam, and the clean gas produced completely meets the requirements of waste pyrolysis. needs, and the surplus part is output as products.

The present invention has been described in detail through specific embodiments above, which are only preferred embodiments of the present invention, and are not intended to limit the present invention. Without departing from the principle of the present invention, all other embodiments obtained by persons of ordinary skill in the art through any modification, equivalent replacement, improvement, etc. without creative work shall be considered as included in the present invention. within the technical scope of protection.

Claims (10)

1. the house refuse low temperature pyrogenation system of a Kernel-based methods decoupling and gas washing burning, it is characterized in that, including feed arrangement, pyrolysis section, gas washing section and heat-recovery section, wherein pyrolysis section includes drying drum and pyrolysis drum, gas washing section includes moving bed adsorbent equipment, plasma air-washer and moving bed absorption plant, and heat-recovery section includes flue gas waste heat recovery apparatus and pyrolysis gas waste-heat recovery device；

Described drying drum includes rotating cylinder in drying drum, drying drum urceolus and drying drum burner, and house refuse is pushed in drying drum in rotating cylinder by a feed arrangement；In described drying drum, rotating cylinder and drying drum urceolus are for sealing structure and being formed with therebetween cavity；In described drying drum, the rear end of rotating cylinder is provided with moisture outlet and composting outlet, this moisture outlet and sewage-treatment plant connection；Described drying drum urceolus is provided with the gas access and exhanst gas outlet that connect with drying drum cavity；On the lateral wall that described drying drum burner is arranged in drying drum rotating cylinder；

Described pyrolysis drum includes rotating cylinder in pyrolysis drum, pyrolysis drum urceolus, pyrolysis drum burner and gas-solid separator, and the rubbish that in drying drum, the composting outlet of rotating cylinder is discharged is pushed in pyrolysis drum in rotating cylinder by another feed arrangement；In described pyrolysis drum, rotating cylinder and pyrolysis drum urceolus are for sealing structure and being formed with therebetween cavity；Described pyrolysis drum urceolus is provided with the gas access and exhanst gas outlet that connect with pyrolysis drum cavity, and this exhanst gas outlet connects with the gas access on drying drum urceolus, and gas access enters for the combustion gas in air and a combustion gas memorizer；Described pyrolysis drum burner is arranged in pyrolysis drum on the lateral wall of rotating cylinder, and described gas-solid separator connects with the rear end of rotating cylinder in pyrolysis drum, and it has pyrolysis gas outlet and breeze outlet, and the outlet of this breeze is connected with a breeze collection device；

Described moving bed adsorbent equipment, plasma getter device and moving bed absorption plant are respectively provided with gas access and gas outlet, the pyrolysis gas outlet of the gas access of moving bed adsorbent equipment and gas-solid separator, the gas access of plasma getter device connects with the gas outlet of moving bed adsorbent equipment, and the gas outlet of plasma getter device connects with the gas access of moving bed absorption plant；

Flue gas waste heat recovery apparatus has high-temperature flue gas entry, low-temperature flue gas exports, cryogenic media entrance and high-temperature medium outlet, pyrolysis gas waste-heat recovery device includes high-temperature hot and vents one's spleen entrance, Low Temperature Thermal is vented one's spleen outlet, cryogenic media entrance and high-temperature medium outlet, the high-temperature flue gas entry of flue gas waste heat recovery apparatus connects with the exhanst gas outlet on drying drum urceolus, low-temperature flue gas outlet and atmosphere, the high-temperature hot of pyrolysis gas waste-heat recovery device entrance of venting one's spleen connects with the gas outlet of moving bed absorption plant, Low Temperature Thermal is vented one's spleen to export and is connected with combustion gas memorizer, flue gas waste heat recovery apparatus all connects with the bottom outlet of a high-temperature steam memorizer with the cryogenic media entrance of pyrolysis gas waste-heat recovery device, flue gas waste heat recovery apparatus exports with the high-temperature medium of pyrolysis gas waste-heat recovery device and all connects with the steam inlet of high-temperature steam memorizer.

2. the house refuse low temperature pyrogenation system of Kernel-based methods decoupling according to claim 1 and gas washing burning, it is characterized in that, the outer surface of the outer surface of described drying drum urceolus and pyrolysis drum urceolus is all covered with aluminium silicate heat-insulation layer or the rock wool heat-preservation layer of 80-120mm.

3. the house refuse low temperature pyrogenation system of Kernel-based methods decoupling according to claim 1 and gas washing burning, it is characterized in that, described feed arrangement all includes a garbage feeding storehouse and a worm propeller, and the rubbish in garbage feeding storehouse is pushed rotating cylinder or pyrolysis in drying drum and rouses in interior rotating cylinder by described worm propeller.

4. the house refuse low temperature pyrogenation system of Kernel-based methods decoupling according to claim 1 and gas washing burning, it is characterised in that be filled with quick lime inside described moving bed adsorbent equipment, is used for heavy metal and the acidic materials of removing in pyrolysis gas；Described plasma air-washer includes six grades of plasma generators of series connection, is used for PM material and the tar of removing in pyrolysis gas；It is filled with dolomite inside described moving bed absorption plant, is used for sulfur-containing compound and the chlorine-containing compound of removing in pyrolysis gas.

5. the house refuse low temperature pyrogenation system of Kernel-based methods decoupling according to claim 1 and gas washing burning, it is characterised in that described pyrolysis drum burner is evenly distributed on the lateral wall of the pyrolysis drum rotating cylinder being positioned at pyrolysis drum urceolus.

6. the house refuse low temperature pyrogenation system of Kernel-based methods decoupling according to claim 1 and gas washing burning, it is characterised in that described flue gas waste heat recovery apparatus and pyrolysis gas waste-heat recovery device are heat-pipe heat exchanger.

7. the house refuse low temperature pyrogenation system of Kernel-based methods decoupling according to claim 1 and gas washing burning, it is characterised in that the inwall of described drying drum urceolus is provided with the helicitic texture guiding flue gas.

8. the house refuse low temperature pyrogenation method of the Kernel-based methods decoupling adopting system described in claim 1 to realize and gas washing burning, it is characterised in that including:

1) house refuse is sent into the interior rotating cylinder of drying drum and is dried process by feed arrangement, the most of moisture of house refuse is expelled to sewage-treatment plant, wherein baking temperature controls, at 120 DEG C 200 DEG C, to control drying time at 0.5h-1h, and the rotating speed of interior rotating cylinder controls at 4-8rpm；

The interior rotating cylinder that dried house refuse is sent into pyrolysis drum carries out pyrolysis processing, generates pyrolysis gas and breeze, and wherein pyrolysis temperature controls at 400 DEG C 600 DEG C, and pyrolysis time controls at 0.5h-1h, and interior rotating cylinder rotating speed controls at 4-8rpm；

The startup stage that the dried of house refuse and pyrolysis processing being divided into and the normal operation stage；

Startup stage, air and combustion gas memorizer output combustion gas mixing after by drying drum burner and pyrolysis drum burner respectively drying drum cavity and pyrolysis drum cavity in combustion heat supplying produce high-temperature flue gas；

Startup stage, completes to enter after the normal operation stage, high-temperature flue gas in pyrolysis drum cavity is delivered in drying drum cavity the house refuse in rotating cylinder in drying drum is carried out heat exchange dries, drying drum burner switches to auxiliary thermal source, continue through pyrolysis drum burner combustion heat supplying in pyrolysis drum cavity after the combustion gas mixing of air and the output of combustion gas memorizer and produce high-temperature flue gas, the water flowed out through the flue gas of heat exchange and high-temperature steam memorizer bottom in drying drum cavity enters in flue gas waste heat recovery apparatus and carries out heat exchange, the water that high-temperature steam memorizer bottom is flowed out absorbs the heat of flue gas and is formed in high-temperature steam entrance high-temperature steam memorizer, fume afterheat is discharged after being absorbed；

2) pyrolysis gas is sent into gas washing section, pass sequentially through moving bed adsorbent equipment, plasma getter device and moving bed absorption plant and carry out purified treatment, pyrolysis gas and the water of high-temperature steam memorizer bottom outflow after washing enter in pyrolysis gas waste-heat recovery device and carry out heat exchange, the water that high-temperature steam memorizer bottom is flowed out absorbs the heat of pyrolysis gas and is formed in high-temperature steam entrance high-temperature steam memorizer, enters combustion gas memorizer after pyrolysis gas release waste heat.

9. the house refuse low temperature pyrogenation method of Kernel-based methods decoupling according to claim 8 and gas washing burning, it is characterised in that be filled with quick lime inside described moving bed adsorbent equipment, is used for heavy metal and the acidic materials of removing in pyrolysis gas；Described plasma air-washer includes six grades of plasma generators of series connection, is used for PM material and the tar of removing in pyrolysis gas；It is filled with base catalyst inside described moving bed absorption plant, is used for sulfur-containing compound and the chlorine-containing compound of removing in pyrolysis gas.

10. the house refuse low temperature pyrogenation method of Kernel-based methods decoupling according to claim 8 and gas washing burning, it is characterised in that containing dolomite in the base catalyst that described moving bed absorption plant is filled.