CN2921607Y - Municipal solid waste gasification melting incineration treatment system - Google Patents

Abstract

The utility model provides a gasification, melting and incineration treatment system for urban domestic garbage, which is composed of a storage bin, a gasification furnace, a dust collector, an incinerator and a high-efficiency heat storage chamber, and is characterized in that the waste heat of the gasification, melting and incineration of garbage is recovered The obtained high-temperature air is then introduced into the gasifier and melting incinerator as the air required for garbage gasification and the combustion air required for melting and incinerating garbage; to ensure stable gasification and complete combustion of garbage, and to completely eliminate dioxins, heavy metals, etc. Secondary pollution of objects. It is in line with the characteristics of low calorific value, high moisture content, loose sorting, and low grade of urban domestic waste. Especially in some small and medium-sized cities, the calorific value and output of waste are even lower and cannot meet the requirements of building waste incineration power plants. Secondary pollution caused by storage and transportation; the scale of the whole system is flexible, and the requirements for garbage sorting and calorific value are not strict, and it can operate stably with little or no auxiliary fuel added, with low cost and zero pollution emission .

Description

Municipal solid waste gasification melting incineration treatment system

technical field

The utility model relates to a treatment technology of urban garbage, in particular to a device for treating urban domestic garbage by gasification, melting, and incineration of high-temperature air.

Background technique

Municipal solid waste disposal has become a common issue faced by countries all over the world. Untreated or improperly treated municipal solid waste will not only encroach on land, pollute groundwater, destroy natural landscapes, but even endanger the safety of people's lives and property. The average annual growth rate of garbage in my country is more than 10%, and at least 2/3 of the more than 400 cities in China are surrounded by garbage; at the same time, garbage contains a large number of biological pathogens and becomes the source of infection for various diseases. According to the survey on the pollution of garbage piled up in the Three Gorges Reservoir area of the Yangtze River, the garbage piled up along the river has been brought into the waters and has become a potential hazard, especially a large amount of white garbage floating on the water surface, which poses a serious hazard to the generator set when it flows through the Gezhou Dam . How to effectively deal with municipal solid waste has become a widely concerned issue.

Municipal solid waste gasification melting incineration technology is divided into one-step gasification melting incineration technology and two-step gasification melting incineration technology. The two-step gasification melting incineration technology is to first gasify the garbage in a reducing atmosphere and a temperature of 500-600 ° C to form flammable combustible gas and residues that are easy to recover metals such as iron and aluminum, and then Carry out combustible gas incineration and high-temperature melting treatment that can suppress the formation of dioxins. The typical process is the thermal selection waste gasification melting gas production technology successfully developed by the Swiss thermal separation company, and then introduced and digested and transformed by the Japanese Kawasaki Iron and Steel Company. The one-step gasification-melting incineration technology puts the drying, gasification, combustion and melting processes of municipal solid waste into one equipment, so the equipment in the whole process is simple, the project investment and operation costs are greatly reduced, and the operation is much easier . The typical process is the NKK direct gasification and melting incineration technology of domestic waste developed by NKK Corporation of Japan. The main equipment of the direct gasification and melting furnace comes from the ironmaking blast furnace, and its biggest feature is that it needs to consume coke. Domestic scientific and technical personnel have done research work on the characteristics of domestic waste in my country. Southeast University has developed a method of drying, gasification and melting of municipal solid waste (patent CN00112320.3); Kunming University of Science and Technology has developed a kind of municipal solid waste Direct gasification melting incineration system (patent CN00259909.0). At present, the common point of various gasification and melting technologies at home and abroad is the power generation mode of "arranging a waste heat boiler after the incinerator to recover the waste heat of the flue gas-arranging a medium-temperature, medium-pressure or low-temperature, low-pressure steam turbine after the waste heat boiler". It is required to reach more than 8300 ~ 9600kJ/kg. The characteristics of urban domestic waste in my country are that the content of inorganic matter is higher than that of organic matter, the content of non-combustible components is higher than that of combustible components, the calorific value is low, the moisture is high, and it also contains certain components of sulfur and chlorine substances. , and the sorting rate is low, and the composition fluctuates greatly. Obviously, simply copying foreign technology and equipment cannot solve the problem of waste incineration in my country. If the power generation mode is used, a large amount of high-quality energy such as coke, coal or fuel oil, which is much higher in grade than waste, must be invested in operation to ensure the normal operation of the system, which will inevitably lead to problems such as large system investment, high operating costs, and low efficiency. . Especially in some small and medium-sized cities, the calorific value and output of waste are lower, which cannot meet the requirements for building waste incineration power stations. The transshipment and stacking of garbage will increase the cost and produce secondary pollution such as stench and infiltration.

Contents of the invention

In view of the above-mentioned deficiencies in the prior art, the purpose of this utility model is to provide a gasification, melting and incineration of municipal solid waste that does not have strict requirements on garbage sorting and calorific value, and can realize harmless, resourceful, and zero-pollution discharge. processing system.

The purpose of this utility model is achieved as follows: the municipal solid waste gasification melting incineration treatment system includes a storage bin, a gasification furnace, a dust collector and an incinerator, and is characterized in that a fully enclosed belt is passed between the storage bin and the gasification furnace. The conveying mechanism is connected; the outlet of the synthetic gas on the upper part of the gasifier is connected to the dust collector, and the outlet of the dust collector is connected to the incinerator, and a swirl burner with tangential air inlet is provided at the connection; the bottom of the dust collector is connected to the gasifier Ash hopper; the high-temperature flue gas outlet of the incinerator is connected to the flue gas side of the high-efficiency regenerator, the flue gas side of the high-efficiency regenerator is connected to the smoke exhaust machine, and the air side inlet of the high-efficiency regenerator is connected to the blower. The high-temperature air outlet communicates with the gasifier and the incinerator through the delivery/nozzle pipe.

The high-efficiency regenerator is composed of a shell lined with refractory materials and heat-storage pellets. The bottom and upper parts are respectively provided with flue gas and air delivery pipes; It is sealed with a sand seal, and the outside is a ball bearing to achieve a high-efficiency heat storage chamber that can rotate back and forth at 180°; the ball is made of refractory materials with high-efficiency heat storage and heat release capabilities and good thermal shock resistance.

The key technical problem of the utility model is: recovering the heat of garbage to obtain high-temperature air; the waste heat of high-temperature flue gas generated after the garbage is gasified, melted and incinerated is stored in a high-efficiency regenerator and heated air is then introduced into the gasifier and melting incinerator. As the air required for garbage gasification and the combustion-supporting air required for melting and incinerating garbage; to ensure stable gasification and complete combustion of garbage without adding or adding less auxiliary fuel, and completely solve the secondary pollution of dioxins, heavy metals, and acid gases pollute.

Compared with the prior art, the utility model has the following advantages:

(1) The method proposed by this utility model based on high-temperature air gasification, melting and incineration to process municipal solid waste, that is, the high-temperature flue gas produced by gasification and combustion is introduced into the high-efficiency regenerator to heat the air, and the heated air is then introduced into gasification, melting and incineration The scheme of treating garbage with a furnace is based on the idea of incinerating garbage as the main purpose to deal with domestic garbage in my country, which is completely different from the current domestic development of incinerating garbage-recovering waste heat power generation mode to deal with urban living garbage. It is in line with the characteristics of low calorific value, high moisture content, loose sorting, and low grade of urban domestic waste in my country. Especially in some small and medium-sized cities, the calorific value and output of waste are even lower and cannot meet the requirements of building waste incineration power plants. Secondary pollution caused by storage and transportation; it is a waste treatment solution for industrial production, flexible regional scale, high efficiency and zero discharge.

(2) The high-efficiency regenerator that obtains high-temperature air has the self-cleaning effect of further purifying the exhausted flue gas: the regenerator in the high-efficiency regenerator has a further "cleaning" effect on the flue gas, even if the flue gas discharged from the melting incinerator still contains Some harmful substances such as fly ash are accumulated in the bed when they pass through the bed of the high-efficiency regenerator. A closed-cycle treatment system that brings harmful substances such as fly ash into the gasification melting incinerator for remelting. The alternating and reverse flow of "flue gas-air" in the regenerator can achieve the effect of self-cleaning. The scale of the whole system is flexible, and the requirements for garbage sorting and calorific value are not strict. It can run stably with little or no auxiliary fuel, and the cost is low. pollutant emission. It is a high-efficiency, energy-saving and environment-friendly waste disposal solution, which meets the requirements of the sustainable development strategy.

Description of drawings

Fig. 1 is the structural representation of the municipal solid waste gasification melting incineration treatment system of the utility model;

Fig. 2 is the A-A cross-sectional view of the high-efficiency regenerator in Fig. 1;

Fig. 3 is a schematic diagram of the rotary connection of the high-efficiency regenerator in Fig. 1 (enlarged at B).

specific implementation plan

As shown in Figure 1, the municipal solid waste gasification melting incineration treatment system includes a storage bin 1, a gasification furnace 2, a dust collector 4, an incinerator 6, a high-efficiency regenerator 8, an ash hopper 5 and an auxiliary burner 7, And the blower 9 and the smoke exhauster 10; the storage bin 1 and the gasifier 2 are connected by a fully enclosed belt conveying mechanism; the outlet of the synthetic gas on the upper part of the gasifier 2 is connected to the dust collector 4, and the outlet of the dust collector 4 is connected to the incinerator 6 The joint is provided with a swirl burner with tangential air intake; the bottom of the dust collector 4 is provided with an ash hopper 5 connected with the gasification furnace; Connected, the flue gas side of the high-efficiency regenerator 8 communicates with the smoke exhauster 10, the air side inlet of the high-efficiency regenerator 8 communicates with the blower 9, and the heated high-temperature air exits through the delivery/nozzle 3 and the gasifier 2 It is connected with the incinerator 6.

The middle part of the incinerator 6 is provided with a partition wall, which divides the incinerator 6 into two chambers communicated at the bottom, so as to prolong the combustion residence time of the synthetic gas therein and make it burn more fully and thoroughly.

The auxiliary burner 7 is mainly used to start the gasification melting incineration waste treatment system and to perform automatic supplementary heat combustion when the temperature of the melting incinerator 6 is too low, and shut down when the system is in normal operation. If the calorific value of the garbage is high or the calorific value of the gasification synthetic gas is high, the remaining part of the waste heat after maintaining the normal operation of the system can be introduced into the hot water boiler 11; if the calorific value of the garbage or the gasification synthetic gas is too low, the melting When the temperature of the incinerator fails to meet the process requirements, the auxiliary burner 7 can be activated through the automatic temperature detection control system to supplement the heat appropriately to ensure the normal operation of the system. Among the figure, 12, 13 and 14 are switching valves.

As shown in Figure 2 and Figure 3, the high-efficiency heat storage chamber is composed of a shell 16 lined with refractory materials and heat storage pellets 15; the bottom and upper parts are respectively provided with flue gas and air delivery pipes; the high-efficiency heat storage The main body of the middle part of the chamber 8 is connected with the upper and lower parts, the inner side is sealed with a sand seal 17, and the outer side is a ball bearing 18 to achieve a high-efficiency regenerator. The regenerator can rotate 180° back and forth, and realize the alternation of small balls on the flue gas side and the air side in the high-efficiency regenerator. The purpose of heat storage and heat release; when the high-temperature flue gas of the incinerator passes through the high-efficiency regenerator, the heat storage ball on the side of the flue gas quickly absorbs the waste heat of the high-temperature flue gas and accumulates it in the body to reach saturation, then quickly rotates 180° Place the high-temperature heat storage balls on the air side, and when the normal temperature air blown by the blower passes through, the heat storage balls quickly release heat and heat the air to 1000°C-1050°C. The pellets are made of high-efficiency heat storage and heat release capabilities and good thermal shock resistance refractory materials, such as high alumina, mullite or cordierite refractory materials.

The method of gasification, melting and incineration of municipal solid waste is to store the primary crushed waste in the storage bin 1, transport it to the high-temperature air gasification furnace 2 through a fully enclosed belt, and heat it to 1000°C through the high-efficiency regenerator 8 The high-temperature air at 1050°C is sprayed into the gasification furnace 2 through the conveying/nozzle 3 to gasify the garbage. The air consumption coefficient is controlled within 0.3 to 0.5, so that the combustible components in the solid waste can undergo incomplete combustion reaction in a high temperature environment above 1300°C to 1350°C. Its incombustible components are transformed into liquid slag, and the synthetic gas with higher calorific value is discharged from the upper part of the gasifier 2 into the dust collector 4 . Harmful substances such as fly ash from the dust collector 4 settle into the ash hopper 5, and at the same time add appropriate absorbents (such as active limestone or lime slurry) to absorb and solidify the harmful substances, and use compressed air to regularly send them into the gasifier 2 for remelting. The purified synthetic gas is sent to the melting incinerator 6, and is fully burned under the high-temperature air combustion of 1000-1050°C. The temperature in the melting and incinerator 6 reaches 1300-1350°C, completely disintegrating the conditions for the existence of dioxins, and at the same time flying The ash melting and the slag discharged from the high-temperature gasifier are solidified to achieve harmless and comprehensive utilization of resources.

The high-temperature flue gas from the incinerator 6 is drawn into the high-efficiency regenerator 8 through the smoke exhauster 10 to exchange heat with the heat-storage pellets 15, so that the high-temperature flue gas from 1300°C to 1350°C is quickly reduced to 200°C to 150°C, avoiding The temperature for dioxin resynthesis is 250°C to 450°C. The air is sent into the high-efficiency regenerator 8 by the blower 9 for heat exchange with the regenerator ball 15, heating the air to 1000°C-1050°C, and the high-efficiency regenerator 8 can rotate back and forth by 180° to ensure the reversing to realize heat storage The heat storage/heat release of the sphere 15 alternates, as shown in FIG. 2 . The heated air is reintroduced into the gasification furnace 2 and the melting incinerator 6 as the air required for garbage gasification and the combustion air required for melting and incinerating garbage, and the remaining part of the waste heat after maintaining the normal operation of the system can be introduced into the hot water boiler 11 .

The high-temperature air temperature of gasification waste reaches 1000℃～1050℃, which can strengthen the gasification reaction, improve the gasification speed and gasification efficiency, and can be carried out at a low air consumption coefficient, while allowing a large proportion of water gas reaction, which can be very good Adapt to the changing characteristics of domestic waste such as calorific value and composition. The air consumption coefficient is controlled within 0.3 to 0.5, so that the combustible components in the solid waste undergo incomplete combustion reactions in a high-temperature environment of 1300°C to 1350°C to produce synthetic gas with a high calorific value, and its non-combustible components are transformed into liquid slag .

The combustible gas discharged from the gasifier is fully combusted under the condition of high-temperature air combustion, and the temperature in the melting and incinerator reaches 1300 ° C ~ 1350 ° C, which completely disintegrates the conditions for the existence of dioxins. Harmless and comprehensive utilization of resources can be realized after curing treatment. Harmful components such as H ₂ S, HCl, and smoke in the synthetic gas are removed by purification, and the ash is returned to the high-temperature gasifier for melting and solidification. Part of the soot that enters the incinerator with the synthetic gas is incinerated, melted and solidified under the condition of high-temperature air combustion. The molten slag is quenched and solidified to form an extremely stable glassy slag, which prevents the release of toxic and heavy metals, and eliminates the possibility of releasing dioxins from the garbage fly ash. The solidified slag can be used as a building material raw material. In addition, there are many similarities between ash and metallurgical charge based on the composition. When the content of valuable metals in ash and slag is high, a certain amount of additives (flux, binder) is added to the solidified fly ash and slag, resulting in Balls, depending on their composition, are used as raw materials for blast furnaces or submerged arc furnaces, allowing the ash to be fully utilized. At the same time, the combination of high-temperature air and low-oxygen combustion technology in the incineration process can effectively suppress the formation of NOx.

The utility model adopts the principle of high-temperature air gasification, and the key is to have a low-cost continuous high-temperature air source. Therefore, the generation of high-temperature air and its optimization and integration with garbage gasification, melting and incineration have become key technical issues for future system promotion and application. For this reason, when formulating the implementation plan, fully consider the goals of harmless waste treatment, reduction and resource utilization, and the ash-containing synthetic gas discharged from the gasifier is treated by a dust collector and then burned in a high-temperature melting incinerator to completely disintegrate Under the condition of dioxins, the fly ash is melted, quenched and solidified to form a very stable glassy slag, so that the poisonous heavy metals will not be dissolved out. The high-temperature flue gas at 1300°C to 1350°C is introduced into the high-efficiency regenerator, and the temperature of the high-temperature flue gas is reduced to 200°C to 150°C through heat exchange, and the cold air is heated to 1000°C to 1050°C to be melted and incinerated as gasified garbage and synthetic gas high temperature air source.

Claims (3)

1. Municipal solid waste gasification melting incineration treatment system, including storage bin (1), gasification furnace (2), dust collector (4) and incinerator (6), characterized in that storage bin (1) and gasification furnace (2) are connected by a fully enclosed belt conveying mechanism; the upper synthetic gas outlet of the gasifier (2) communicates with the dust collector (4), and the outlet of the dust collector (4) communicates with the incinerator (6). A swirl burner with tangential air intake; the bottom of the dust collector (4) is provided with an ash hopper (5) communicated with the gasifier (2); the high-temperature flue gas outlet of the incinerator (6) and the high-efficiency regenerator ( 8) The flue gas side is connected, the flue gas side of the high-efficiency regenerator (8) is connected to the exhaust machine (10), the air side inlet of the high-efficiency regenerator (8) is connected to the blower (9), and the heated high temperature The air outlet communicates with the gasifier (2) and the incinerator (6) through the delivery/nozzle pipe (3). 2. The gasification melting incineration treatment system according to claim 1, characterized in that the high-efficiency regenerator (8) is composed of a shell (16) lined with refractory material and heat storage pellets (15), and the bottom The upper part and the upper part are respectively provided with flue gas and air conveying pipes; the middle body of the high-efficiency regenerator is connected with the upper and lower parts, and the inner side is sealed with a sand seal (17), and the outer side is a ball bearing (18) to achieve the high-efficiency regenerator. 180° reciprocating rotation; the ball is made of refractory material with high-efficiency heat storage and heat release capacity and good thermal shock resistance. 3. The gasification melting incineration treatment system according to claim 1, characterized in that the high-efficiency regenerator (8) is introduced into the hot water boiler (11) through the delivery pipe (3).