CN107120660A - A kind of domestic garbage pyrolysis incinerator flue gas purification system - Google Patents

Abstract

The invention relates to a flue gas purification system of a domestic waste pyrolysis incineration device; comprising a quench tower, an electromagnetic pulse dust collector, a waste heat utilization and cooling device, a carbon fiber filter device, a heat exchange device, a dioxin chemical catalyst device, a water supply system, Flue gas pipeline and induced draft fan; it is characterized in that the inlet end of the quenching tower is connected with the flue gas pipeline of the domestic waste pyrolysis incinerator, the outlet end of the quenching tower is connected with the electromagnetic pulse dust collector, and the electromagnetic pulse dust collector is connected with waste heat utilization and The cooling device is connected, the waste heat utilization and cooling device is connected with the carbon fiber filter device, the carbon fiber filter device is connected with the induced draft fan, the outlet of the induced draft fan is connected with a heat exchange device, and the outlet of the heat exchange device is connected with a dioxin chemical catalyst device. The oxin chemical catalytic device is connected to the chimney, and the flue gas is finally discharged into the atmosphere after a series of purification. It can effectively remove pollutants in the incineration flue gas, including CO, SO ₂ , NO _X , dioxin, etc., and the concentration of dioxin meets the national standard.

Description

A flue gas purification system of domestic waste pyrolysis incineration device

technical field

The invention relates to a system in the field of domestic waste treatment and resource utilization, in particular to a flue gas purification system of a domestic waste pyrolysis incineration device.

Background technique

At present, the commonly used garbage disposal methods in my country include: sanitary landfill method, garbage composting method and heat treatment method. Sanitary landfill is the main way of waste disposal in my country at present. This treatment method is simple in technology and has a large processing capacity, but it occupies too much land resources, and there are problems such as difficult site selection, leachate pollution, and greenhouse gas emissions. resource utilization. Due to the increasing amount of packaging materials, paper and plastics in domestic waste, it has brought some problems to waste composting, and after composting, it is easy to cause land salinization and difficult market access for products, which limits its development. . The waste heat treatment technology has obvious advantages in volume reduction, volume reduction, and resource utilization. The new waste incineration technology has received national attention in recent years and will be the main direction of waste treatment and resource utilization in the future.

The essence of heat treatment technology is to oxidize and decompose garbage at high temperature to form stable solid residues. However, during pyrolysis and incineration, a large amount of harmful gases will be released, and dust and fine particles will fly with the wind, resulting in various pollutants in the air. Exceeding the standard, and will produce a large amount of strong carcinogen dioxin, which is the main factor restricting pyrolysis incineration treatment technology at present.

In order to prevent secondary pollution to the environment during the waste incineration process, strict measures must be taken to control the emission of waste incineration flue gas by using the flue gas purification system. There are three treatment processes for the removal of acid gases in flue gas: dry method, semi-dry method and wet method. The semi-dry purification process can achieve high purification efficiency, low investment and operating costs, simple process, and no waste water. Most European incineration plants use the semi-dry method. The semi-dry method has been successfully applied in many cases in China, and has accumulated a certain amount of operating experience. It is suitable for incineration plants with higher emission standards. Now most of the waste incineration power plants under construction and to be built in China use the semi-dry method. . The dry purification process is relatively simple in process, low in investment, and convenient in operation and maintenance, but the purification efficiency of the dry process is relatively low, and it has been widely used in the construction of incineration plants in Japan in recent years. The wet purification process has the highest pollutant purification efficiency and can meet the most stringent emission standards. However, due to the complex process, more supporting equipment, high one-time investment and high operating costs, it is widely used in economically developed countries, but not widely used in China. As far as the removal effect of NOx is concerned, the removal rate of SCR to NOx has reached more than 90%, while the removal rate of SNCR to NOx can also reach about 50%. In terms of cost-efficiency analysis, SCR is basically equivalent to advanced incineration control systems, and is obviously more expensive than SNCR technology. Since the late 1980s, more waste incineration plants have used bag filters, and their dust removal efficiency can reach more than 99.9%. my country's "Technical Specifications for Domestic Waste Incineration Treatment Engineering" (CJJ90-2009) clearly stipulates that the dust removal device of domestic waste incinerator must use a bag filter. Electrostatic precipitators have been widely used in waste incineration plants since the 1970s. With the strengthening of the concept of environmental protection, the adsorption of activated carbon on dioxins and heavy metals is increasingly used by waste incineration power plants.

The flue gas produced during the incineration process of domestic waste mainly contains harmful substances such as SO ₂ , HCl, NOx, heavy metals and dioxins. In recent years, in addition to the traditional desulfurization and denitrification and the control of particulate matter, dioxin pollution has attracted widespread attention from people all over the world, and waste incineration plants are one of the main sources of dioxins. The mechanism has not yet reached a unified consensus, so it is difficult to determine the effect of inhibiting the formation of dioxins by only controlling the incineration parameters, so the subsequent treatment of dioxins becomes particularly critical. With the development of the economy, the emission standards of waste incineration flue gas are becoming more and more stringent. Dioxin has changed from 1mg/m ³ to 0.5mg/m ³ at the beginning, and now it is 0.1mg/m ³ . Processing is also in dire need of new changes.

Contents of the invention

The present invention provides a flue gas purification system of a domestic waste pyrolysis incineration device, which can effectively remove pollutants in the incineration flue gas, including CO, SO ₂ , NO _X , dioxin, etc., especially for dioxins, which are difficult to handle. The dioxins have been treated in multiple stages, and the concentration of dioxins in the exhaust flue gas can reach more than three times higher than the national standard, which has achieved the purpose of environmental protection.

Technical scheme of the present invention is as follows:

A flue gas purification system of a domestic waste pyrolysis incineration device, including a quench tower, an electromagnetic pulse dust collector, a waste heat utilization and cooling device, a carbon fiber filter device, a heat exchange device, a dioxin chemical catalyst device, a water supply system, and a flue gas pipeline and an induced draft fan; it is characterized in that the inlet end of the quenching tower is connected to the flue gas pipeline of the domestic waste pyrolysis incineration device, the outlet end of the quenching tower is connected with the electromagnetic pulse dust collector, and the electromagnetic pulse dust collector is connected with the waste heat utilization and cooling device , the waste heat utilization and cooling device is connected with the carbon fiber filter device, the carbon fiber filter device is connected with the induced draft fan, the outlet of the induced draft fan is connected with the heat exchange device, the outlet of the heat exchange device is connected with the dioxin chemical catalytic device, and the dioxin chemical The catalytic device is connected to the chimney, and the flue gas is finally discharged into the atmosphere after a series of purification.

Spray pipes are arranged on the upper part of the quench tower; the temperature of the flue gas after cooling is 160°C-180°C.

The electromagnetic pulse dust collector is composed of many cloth bags, and the pollutants in the flue gas are adsorbed on the surface of the filter bags.

The electromagnetic pulse dust collector is provided with a pulse valve.

An additive dosing device is installed on the flue gas pipeline between the quench tower and the electromagnetic pulse dust collector; calcium hydroxide and reaction additives are added to remove various acid gases and dioxins in the flue gas, The flue gas temperature is reduced to 100°C-140°C.

A waste heat utilization and cooling device is connected between the electromagnetic pulse dust collector and the carbon fiber filter device; the flue gas after thermal energy utilization enters the cooling device to reduce the temperature of the flue gas to 40°C-60°C.

The carbon fiber filter device is composed of several carbon fiber filter elements arranged in an orderly manner.

The induced draft fan is located behind the carbon fiber filter device, and adopts frequency conversion speed regulation to ensure the furnace pressure required by the pyrolysis incineration device under different working conditions.

The heat exchange device is located above the pyrolysis incinerator; the temperature reaches 210°C-250°C.

The dioxin chemical catalytic device is composed of several catalyst modules, and the whole is an upright cuboid. The catalyst in the module can catalyze, oxidize and decompose dioxin to generate harmless substances.

The specific instructions are as follows:

The main function of the quenching tower is to cool down the flue gas produced by the garbage pyrolysis incineration device. The upper part of the quenching tower is equipped with a spray pipe, and the spraying pipe is installed on the upper part of the quenching tower. Spray down the shower pipe to cool down the flue gas rapidly, and the cooling water is recycled.

The electromagnetic pulse dust collector is composed of many cloth bags, and the pollutants in the flue gas are adsorbed on the surface of the filter bags, which can effectively remove acid and adsorb harmful gases such as dioxins.

The electromagnetic pulse dust collector is equipped with a pulse valve, and each time a group of pulse valves is opened to remove the dust in the part of the bag or filter cartridge it controls, while other bags or filter cartridges work normally, after a period of time, the next group The pulse valve opens and cleans the dust collector as described in the next section.

An additive dosing device is installed on the flue gas pipeline between the quench tower and the electromagnetic pulse dust collector, and calcium hydroxide and reaction additives (activated carbon powder) are added to remove various acid gases and Dioxins.

The carbon fiber filter device is composed of several carbon fiber filter elements arranged in an orderly manner, which can further filter and adsorb harmful gases such as dioxins in the flue gas.

The induced draft fan is located behind the carbon fiber filter device and adopts frequency conversion speed regulation. Its function is to ensure the furnace pressure required by the pyrolysis incineration device under different working conditions, and the second is to discharge the carbon fiber filter device. The flue gas is drawn into the heat exchange device.

The heat exchange device is located above the pyrolysis incinerator, and the flue gas is sent into the heat exchange device by the induced draft fan for temperature rise treatment.

The dioxin chemical catalytic device is composed of several catalyst modules, and the whole is a vertical cuboid. The catalyst in the module can catalyze and oxidize and decompose dioxin to generate harmless water vapor, carbon dioxide, hydrogen chloride and other substances , The service life is more than 16000 hours.

Compared with the prior art, the present invention has the following beneficial effects:

1. This system can purify the flue gas emitted by thermal incineration of domestic waste to meet or even significantly exceed the national standard, and can consider using the sensible heat in the flue gas to produce low-pressure steam for production and daily use in factories;

2. This system adopts a two-stage method for treating dioxins in flue gas, and the concentration of dioxins after treatment can reach higher than the national standard;

3. This system sucks the flue gas through the carbon fiber filter device into the heat exchange device to heat up, which is beneficial to the subsequent treatment of dioxin chemical catalyst device;

4. The system only has two water pumps, one air pump and one induced draft fan, which reduces auxiliary equipment, increases the safety and reliability of the system, and reduces the operating cost of the system;

5. The incineration flue gas has been thoroughly purified, reducing the emission of flue gas and reducing environmental pollution.

6. The flue gas purification system of the domestic waste pyrolysis incineration device provided by the present invention can effectively remove pollutants in the incineration flue gas, including CO, SO ₂ , NO _X , dioxin, etc., especially dioxins in the exhaust flue gas. The concentration of oxins can meet the national standard (<0.03ng/m ³ ).

Description of drawings

Figure 1: Schematic diagram of the structure of the flue gas purification system of the domestic waste pyrolysis incinerator.

Among them, 1. Domestic waste pyrolysis incinerator; 2. Rapid cooling tower; 3. Electromagnetic pulse dust collector; 4. Waste heat utilization and cooling device; 5. Carbon fiber filter device; 6. Induced fan; 7. Heat exchange device; 8 1. Dioxin chemical catalyst device; 9. Chimney; 10. Auxiliary dosing device 1; 11. Auxiliary dosing device 2; 12. Spray pipe; 13. Cloth bag.

detailed description

The present invention will be further described below in conjunction with accompanying drawing:

The flue gas purification system of the domestic waste pyrolysis incineration device proposed by the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. Advantages and features of the present invention will be apparent from the following description and claims. It should be noted that the drawings are all in a very simplified form and use imprecise ratios, which are only used to facilitate and clearly assist the purpose of illustrating the embodiments of the present invention.

Please refer to FIG. 1 , which is a schematic structural diagram of a flue gas purification system of a domestic waste pyrolysis incineration device provided by an embodiment of the present invention.

An embodiment of the present invention provides a flue gas purification system of a domestic waste pyrolysis incineration device, which includes a quench tower (2), an electromagnetic pulse dust collector (3), a waste heat utilization and cooling device (4), and a carbon fiber filter device (5) , a heat exchange device (7), a dioxin chemical catalyst device (8), a water supply system, a flue gas pipeline and an induced draft fan (6), the inlet end of the quench tower (2) is connected to the smoke of the domestic waste pyrolysis incineration device The air pipeline is connected, the outlet end of the quench tower (2) is connected with the electromagnetic pulse dust collector (3), the electromagnetic pulse dust collector (3) is connected with the waste heat utilization and cooling device (4), and the waste heat utilization The cooling device (4) is connected with the carbon fiber filter device (5), the carbon fiber filter device (5) is connected with the induced draft fan (6), and the flue gas is sent into the fan (6) through the induced draft fan (6). After the heating device (7) heats up, it enters the dioxin chemical catalysis device (8), and the dioxin chemical catalysis device (8) is connected with the chimney (9), and the flue gas is finally discharged into the atmosphere after a series of purification.

A spray pipe (12) is arranged on the inner upper part of the quench tower (2), and the spray pipe (12) is installed on the upper part of the quench tower, and cooling water is sprayed down from the spray pipe 12.

The electromagnetic pulse dust collector (3) is composed of many cloth bags (13), and the pollutants in the flue gas are adsorbed on the surface of the filter bags, which can effectively remove acid and adsorb harmful gases such as dioxins.

An auxiliary agent dosing device 1 (10), an auxiliary agent dosing device 2 (11) are installed on the flue gas pipeline between the quench tower (2) and the described electromagnetic pulse dust collector (3), and the hydrogen oxidation Calcium and reaction additives (activated carbon powder) to remove various acid gases and dioxins in the flue gas.

Thermocouples are installed in each main part of the flue gas purification system of the domestic waste pyrolysis incineration device, and the PLC automatic control system is used to monitor the temperature change, and at the same time, the addition of additives and the power of the fan can also be controlled.

When the system is in normal operation, domestic garbage is thermally decomposed in the pyrolysis incinerator (1). The furnace body has a diameter of 1.2m and a height of 1.88m. It is made of Q235 carbon steel. The inner layer is refractory high-temperature material, and the outer wall steel plate is 6mm thick. , 8mm thick inner tank steel plate, 100mm thick refractory material layer, 8-10h working hours per day, 10t/d processing capacity, and 700°C-900°C furnace temperature. The flue gas produced by pyrolysis and incineration is sent into the quenching tower (2) through the flue gas pipeline, and the spray pipe (12) in the quenching tower (2) starts to spray water, and the cooling water rapidly cools the flue gas. Cooling, and the cooling water can be recycled. After cooling, the temperature of the flue gas is reduced to 160°C-180°C. Adding device 2 (11) adds activated carbon powder; the rated power of the lime pump and activated carbon powder pump is 0.75kw, and the dosage is adjusted by the PLC automatic control system, mainly to reduce various acid gases and dioxins in the flue gas, Calcium hydroxide neutralizes acid gas, and activated carbon powder adsorbs dioxins. After the flue gas is rapidly cooled and reacted by adding additives, the temperature decays to 100°C-140°C, and the unreacted calcium hydroxide and reaction additives (activated carbon powder) enter the electromagnetic pulse bag filter (3), Adsorbed on the surface of the filter bag, it can effectively remove acid and adsorb harmful gases such as dioxins. The content of particulate matter in the flue gas is reduced to below 5mg/ ^m3 , NOx is reduced to about 400mg/ ^m3 , and _SO2 is reduced to 100mg/ ^m3 About 2 ~ 3ng/m ³ of dioxins. Because the temperature required for carbon fiber adsorption is low, the high-temperature flue gas pipeline section at the outlet of the electromagnetic pulse dust collector (3) is provided with the waste heat recovery and utilization device (4), which collects heat energy in the high-temperature flue gas with a heat exchange device, The flue gas after thermal energy utilization enters the cooling device to continue to cool down, so that the temperature of the flue gas drops to 40°C-60°C. After the flue gas is cooled, it enters the carbon fiber filter device (5), which is composed of several carbon fiber filter elements arranged in an orderly manner. The price of the activated carbon adsorption material is 10w/t, and the consumption is 150kg. Dioxin and other harmful gases are filtered and adsorbed, and the dioxin content in the treated flue gas is reduced to below 1ng/ ^m3 . The induced draft fan (6) is arranged behind the carbon fiber filtering device (5), and the induced draft fan (6) adopts frequency conversion speed regulation, and its function is to ensure The required furnace pressure makes the incineration pyrolysis furnace in a negative pressure state; the second is to suck the outlet flue gas of the carbon fiber filter device (5) into the heat exchange device (7), because the adopted new The applicable temperature of the dioxin removal catalyst is 180°C-250°C, the flue gas passes through the heat exchange device (7) to reach 210°C-250°C, and then enters the dioxin chemical catalyst device (8). The device is composed of several catalyst modules, and the whole is a vertical cuboid. The catalyst is a new type of de-dioxin catalyst developed by a company in Shanghai. The catalyst is honeycomb or granular, and the price is 13w/m ³ . The catalyst inside can catalyze and oxidize and decompose dioxin to produce harmless water vapor, carbon dioxide, hydrogen chloride and other substances, and the service life is more than 16,000 hours. The treated flue gas can achieve the effects shown in Table 1, and meets the requirements of the "Standards for Pollution Control of Domestic Waste Incineration" (GB18485-2014) for the limit value of flue gas pollutants emitted by domestic waste incinerators, and finally passes through the chimney (9) into the atmosphere.

Table 1 Flue gas pollutant indicators after treatment

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (10)

1. A flue gas purification system of a domestic waste pyrolysis incineration device, including a quench tower, an electromagnetic pulse dust collector, a waste heat utilization and cooling device, a carbon fiber filter device, a heat exchange device, a dioxin chemical catalyst device, a water supply system, and a flue gas Gas pipeline and induced draft fan; it is characterized in that the inlet end of the quenching tower is connected with the flue gas pipeline of the domestic waste pyrolysis incineration device, the outlet end of the quenching tower is connected with the electromagnetic pulse dust collector, and the electromagnetic pulse dust collector is connected with waste heat utilization and cooling The device is connected, the waste heat utilization and cooling device is connected with the carbon fiber filter device, the carbon fiber filter device is connected with the induced draft fan, the outlet of the induced draft fan is connected with the heat exchange device, the outlet of the heat exchange device is connected with the dioxin chemical catalyst device, and the dioxin The British chemical catalytic device is connected to the chimney, and the flue gas is finally discharged into the atmosphere after a series of purification. 2. The device according to claim 1, characterized in that a spray pipe is arranged on the upper part of the quench tower; the flue gas temperature is 160°C-180°C after cooling. 3. The device according to claim 1, characterized in that the electromagnetic pulse dust collector is composed of many cloth bags, and the pollutants in the flue gas are adsorbed on the surface of the filter bags. 4. The device according to claim 1, characterized in that the electromagnetic pulse dust collector is provided with a pulse valve, each time a group of pulse valves are opened to remove the dust of the part of the bag or filter cartridge it controls, while the other The bag or filter cartridge works normally, and after a period of time, the next set of pulse valves is opened to clean the dust collector described in the next section. 5. The device according to claim 1, characterized in that an auxiliary agent dosing device is installed on the flue gas pipeline between the quench tower and the electromagnetic pulse dust collector; add calcium hydroxide and reaction auxiliary agent, Various acid gases and dioxins in the flue gas are removed, and the temperature of the flue gas is reduced to 100°C-140°C. 6. The device according to claim 1, characterized in that a waste heat utilization and cooling device is connected between the electromagnetic pulse dust collector and the carbon fiber filter device; the flue gas after thermal energy utilization enters the cooling device again, so that the smoke Air temperature drops to 40°C-60°C. 7. The device according to claim 1, characterized in that the carbon fiber filter device is composed of several carbon fiber filter elements arranged in an orderly manner. 8. The device according to claim 1, characterized in that the induced draft fan is located behind the carbon fiber filter device and adopts frequency conversion speed regulation to ensure the furnace pressure required by the pyrolysis incineration device under different working conditions. 9. The device according to claim 1, characterized in that the heat exchange device is located above the pyrolysis incinerator; the temperature reaches 210°C-250°C. 10. The device according to claim 1, characterized in that the dioxin chemical catalytic device is composed of several catalyst modules, the whole is an upright cuboid, and the catalyst in the module can catalyze the oxidation of dioxin Decomposes to produce harmless substances.