Method for capturing and harmless treatment of organic pollutants and precursors emitted by coal burning

Abstract

The present application relates to a kind of method for capturing and harmless treatment of organic pollutants and its precursor discharged by coal-fired.The present application uses the mechanism of high-efficiency adsorption capture of adsorbent under different temperature field conditions, high-efficiency removal and collection of fine particles including adsorbent, high-temperature combustion of collected fine particles, so that the organic pollutants and its precursor discharged by coal-fired adsorbed in adsorbent are efficiently captured and finally completely harmless treated.The present application sets up hearth adsorbent injection device and fine particle combustion device in lower part of boiler furnace respectively, sets up tail adsorbent injection device in high-temperature flue at the tail of boiler, and sets up fine particle removal device in low-temperature flue at the tail of boiler, which provides a kind of method for high-efficiency removal and harmless treatment of organic pollutants and its precursor in industrial flue gas such as coal-fired, oil-fired and waste incineration, which has high removal efficiency, complete harmless treatment, low operation cost, convenient maintenance and operation maintenance, and is suitable for high-efficiency removal and harmless treatment of organic pollutants and its precursor in industrial flue gas such as coal-fired, oil-fired and waste incineration.

Description

Technical Field

[0001] This invention relates to a method for capturing and rendering harmless the organic pollutants and their precursors emitted from coal combustion, and more particularly to a method for efficiently capturing and rendering harmless the organic pollutants and their precursors emitted from coal combustion, comprising a furnace adsorbent injection device, a tail-end adsorbent injection device, a fine particle removal device, and a fine particle combustion device. Background Technology

[0002] Currently, my country's processes and technologies for capturing and harmlessly treating organic pollutants and their precursors emitted from coal combustion are still in the early stages of basic research and development. The processes and devices currently being tested and applied have not yet achieved efficient control and removal effects, and are characterized by complex processes, poor operational stability, large equipment investment, and high operating and maintenance costs. Furthermore, a more prominent problem is that some pollutants, after being removed, often re-enter the environment after transfer, failing to achieve final and complete harmless treatment.

[0003] This invention employs mechanisms such as efficient adsorption and capture of adsorbents under different temperature conditions, efficient removal and collection of fine particles including the adsorbent, and high-temperature combustion of the collected fine particles, so that organic pollutants and their precursors adsorbed in the adsorbent from coal combustion emissions can be efficiently captured and completely rendered harmless. Summary of the Invention

[0004] The purpose of this invention is to provide a method for capturing and rendering harmless the organic pollutants and their precursors emitted from coal combustion. This method employs a highly efficient method for capturing and rendering completely harmless the pollutants and their precursors by installing a furnace adsorbent injection device and a fine particulate combustion device in the lower part of the boiler furnace, a tail-end adsorbent injection device in the high-temperature flue at the boiler tail end, and a fine particulate removal device in the low-temperature flue at the boiler tail end. This invention achieves high capture efficiency and complete harmless treatment of organic pollutants and their precursors emitted from coal combustion, has low operating costs, and is convenient for inspection and maintenance. It is applicable to the purification of pollutants in industrial flue gas from coal, oil, and waste incineration.

[0005] To achieve the above objectives, the furnace adsorbent injection device of the present invention is located in the lower part of the boiler furnace. The injected adsorbent is a porous particulate matter with a high specific surface area, formed by activated and modified fly ash, possessing extremely strong physicochemical adsorption capabilities. After being injected into the furnace by this device, the adsorbent's rich ultrafine pores and metal oxide catalytic sites exert a strong physicochemical adsorption effect on organic pollutants and their precursors in the flue gas. Furthermore, after being injected into the furnace, the adsorbent is uniformly dispersed throughout the furnace, resulting in high efficiency and effectiveness in the physicochemical adsorption and capture of organic pollutants and their precursors in the flue gas. The tail-end adsorbent injection device of the present invention is located in the high-temperature flue at the tail end of the boiler. The injected adsorbent is a porous particulate matter with a high specific surface area, formed by activated and modified fly ash with a certain carbon content, exhibiting extremely strong physicochemical adsorption capabilities at this temperature range. After the adsorbent is sprayed into the high-temperature flue gas at the tail end through this device, its rich ultrafine pores, carbon adsorption sites, and metal oxide catalytic sites exert a strong physicochemical adsorption effect on organic pollutants and their precursors in the flue gas at the tail end, and the adsorption and capture efficiency is high and the effect is good.

[0006] The fine particle removal device of this invention is installed in the low-temperature flue at the tail end of the boiler. The fine particles, including the adsorbent, collected by the fine particle removal device are discharged through the fine particle discharge port. After being discharged through the fine particle discharge port, the fine particles are transported to the fine particle combustion device installed in the boiler furnace, where they are finally fully combusted at high temperature in the boiler furnace, achieving complete harmless treatment.

[0007] Compared with existing technologies, this invention has the following characteristics:

[0008] (1) Due to the use of different types of adsorbents to carry out efficient physicochemical adsorption of organic pollutants and their precursors formed and emitted during coal combustion under different temperature field conditions, the organic pollutants and their precursors during coal combustion are fully adsorbed and captured, and the purification efficiency of organic pollutants and their precursors is >90%.

[0009] (2) The adsorbent that adsorbs organic pollutants and their precursors achieves the final and complete harmless treatment of organic pollutants and their precursors by high-temperature incineration in the furnace.

[0010] (3) The present invention has a compact structure, high efficiency in removing organic pollutants and their precursors formed and emitted during coal combustion, and achieves the final complete harmless treatment of organic pollutants and their precursors. The equipment investment and operating costs are low, and the inspection and maintenance are convenient. Attached Figure Description

[0011] The present invention will now be described in further detail with reference to the accompanying drawings.

[0012] Figure 1 This is a schematic diagram of the present invention.

[0013] In the diagram: 1. Boiler, 2. Furnace adsorbent injection device, 3. Tail adsorbent injection device, 4. Fine particle removal device, 5. Fine particle discharge port, 6. Fine particle combustion device, 7. Clean flue gas outlet. Detailed Implementation

[0014] Figure 1 In the boiler (1), a furnace adsorbent injection device (2) and a fine particle combustion device (6) are respectively installed in the lower part of the furnace. A tail adsorbent injection device (3) is installed in the high-temperature flue at the tail of the boiler, and a fine particle removal device (4) is installed in the low-temperature flue at the tail of the boiler. The tail adsorbent injection device (3) is connected to the fine particle removal device (4) through the flue. The fine particles, including the adsorbent, collected by the fine particle removal device (4) are discharged through the fine particle discharge port (5). The fine particle removal device (4) is connected to the fine particle combustion device (6) through the conveying pipe of the fine particle discharge port (5). After being discharged through the fine particle discharge port (5), the fine particles are transported to the fine particle combustion device (6) installed in the furnace of the boiler (1) and finally fully combusted at high temperature in the furnace of the boiler (1) to achieve complete harmless treatment.

[0015] When the method of the present invention is in operation, the furnace adsorbent injection device (2) located in the lower part of the furnace of the boiler (1) and the tail adsorbent injection device (3) located in the high-temperature flue at the tail end of the boiler (1) inject adsorbents of different specifications into the furnace and the flue, respectively. After the adsorbent is injected, its rich ultrafine pores, carbon adsorption sites, metal oxide catalytic sites, etc., play a strong physicochemical adsorption role on organic pollutants and their precursors in the flue gas under different temperature field conditions. The adsorbent enters the fine particle removal device (4) located in the low-temperature flue at the tail end of the boiler (1) with the flue gas. The fine particles, including the adsorbent, collected by the fine particle removal device (4) are discharged through the fine particle discharge port (5). After being discharged through the fine particle discharge port (5), the fine particles are transported to the fine particle combustion device (6) located in the furnace of the boiler (1) and finally fully combusted at high temperature in the furnace of the boiler (1) to achieve complete harmless treatment.

[0016] The above are merely specific embodiments of the present invention. The technical features of the present invention are not limited thereto. Any changes or modifications made by those skilled in the art within the scope of the present invention should be included in the patent scope of the present invention.

Claims

1. A method for capturing and harmlessly treating organic pollutants and precursors emitted from coal combustion, wherein the method is implemented through a device for capturing and harmlessly treating organic pollutants and precursors emitted from coal combustion, wherein the device includes a furnace adsorbent injection device, a tail-end adsorbent injection device, a fine particle removal device, and a fine particle combustion device, characterized in that: A furnace adsorbent injection device and a fine particle combustion device are respectively installed in the lower part of the boiler furnace. The adsorbent injected by the furnace adsorbent injection device is a porous particulate matter with a large specific surface area formed by activated and modified fly ash. A tail-end adsorbent injection device is installed in the high-temperature flue at the tail end of the boiler. The adsorbent injected by the tail-end adsorbent injection device is a porous particulate matter with a large specific surface area formed by activated and modified fly ash with a certain carbon content. A fine particle removal device is installed in the low-temperature flue at the tail end of the boiler. The fine particle removal device is connected to the fine particle combustion device through the conveying pipe of the fine particle discharge outlet. The tail-end adsorbent injection device is connected to the fine particle removal device through the flue.

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