阅读说明：本技术 一种高效生物菌剂脱硫脱氮工艺 (High-efficiency biological agent desulfurization and denitrification process ) 是由 朱天文 陈川 汤华国 倪琦 于 2021-09-28 设计创作，主要内容包括：本发明涉及一种高效生物菌剂脱硫脱氮工艺,它包括以下步骤：步骤一：将含硫含氮的废气由风机送至除尘装置进行除尘,除尘后的废气进行使用换热器进行冷却处理；步骤二：分别将微生物及其营养物配料存在于液相中,形成脱氮菌剂液相和脱硫剂液相,两者形成复合菌剂,废气与复合菌剂在生物洗涤器中充分接触,废气中的污染物被微生物净化后排出；步骤三：对废气进行增湿,后进入生物滤床,废气中的污染物从气相转移到生物膜表面并被微生物净化后排出。本发明与现有技术相比的优点在于：微生物的环境条件及操作条件容易控制,不易发生二次污染,且净化效果好。(The invention relates to a high-efficiency biological agent desulfurization and denitrification process, which comprises the following steps: the method comprises the following steps: sending the waste gas containing sulfur and nitrogen to a dust removal device by a fan for dust removal, and cooling the waste gas after dust removal by using a heat exchanger; step two: respectively enabling microorganisms and nutrient ingredients thereof to exist in a liquid phase to form a denitrogenation microbial inoculum liquid phase and a desulfurizer liquid phase, wherein the denitrogenation microbial inoculum liquid phase and the desulfurizer liquid phase form a composite microbial inoculum, the waste gas is fully contacted with the composite microbial inoculum in a biological scrubber, and pollutants in the waste gas are discharged after being purified by the microorganisms; step three: humidifying the waste gas, then introducing the waste gas into a biological filter bed, transferring pollutants in the waste gas from a gas phase to the surface of a biological membrane, purifying the pollutants by microorganisms, and then discharging the pollutants. Compared with the prior art, the invention has the advantages that: the environmental condition and the operation condition of the microorganism are easy to control, the secondary pollution is not easy to occur, and the purification effect is good.)

1. A high-efficiency biological agent desulfurization and denitrification process is characterized by comprising the following steps: it comprises the following steps:

the method comprises the following steps: sending the waste gas containing sulfur and nitrogen to a dust removal device by a fan for dust removal, and cooling the waste gas after dust removal by using a heat exchanger;

step two: respectively enabling microorganisms and nutrient ingredients thereof to exist in a liquid phase to form a denitrogenation microbial inoculum liquid phase and a desulfurizer liquid phase, wherein the denitrogenation microbial inoculum liquid phase and the desulfurizer liquid phase form a composite microbial inoculum, the waste gas is fully contacted with the composite microbial inoculum in a biological scrubber, and pollutants in the waste gas are discharged after being purified by the microorganisms;

step three: humidifying the waste gas, then introducing the waste gas into a biological filter bed, transferring pollutants in the waste gas from a gas phase to the surface of a biological membrane, purifying the pollutants by microorganisms, then discharging the pollutants, and spraying the pollutants above the biological filter bed.

2. The desulfurization and denitrification process of the high-efficiency biological agent as claimed in claim 1, characterized in that: in the second step, the liquid-phase strain of the denitrifier is one or more of achromobacter, alcaligenes, bacillus, chromobacterium and corynebacterium, and the desulfurizing bacteria of the desulfurizing agent liquid phase is one of vibrio desulfurizati, thiobacillus thioparus and thiobacillus ferrooxidans.

3. The desulfurization and denitrification process of the high-efficiency biological agent as claimed in claim 1, characterized in that: and in the second step, the biological scrubber is a spray tower or a bubble tower.

4. The desulfurization and denitrification process of the high-efficiency biological agent as claimed in claim 1, characterized in that: the temperature of the waste gas cooled by the heat exchanger in the step one is below 30 ℃.

5. The desulfurization and denitrification process of the high-efficiency biological agent as claimed in claim 1, characterized in that: the biological filter bed consists of a filter material bed layer, a gravel layer and a porous air distribution pipe, wherein the porous air distribution pipe is arranged in the gravel layer, and the filter material bed layer is filled with bioactive fillers.

Technical Field

The invention relates to the field of flue gas treatment, in particular to a high-efficiency biological agent desulfurization and denitrification process.

Background

China is the largest coal producing country and consuming country in the world, coal accounts for about 75% of energy demand in China, sulfur, chlorine and nitrogen oxides generated by coal combustion are main pollution sources of air pollution, and besides acid rain is formed, photochemical smog can be formed by destroying the ecological environment, and the photochemical smog is harmful to human health, and large-scale power station boilers and numerous industrial boilers are main emission sources.

The desulfurization and denitrification integrated technology widely used at home and abroad at present is mainly wet flue gas desulfurization. The wet flue gas desulfurization is usually carried out by a calcium method using lime or limestone, the desulfurization efficiency is more than 90%, and the wet flue gas desulfurization has the defects of huge engineering, high initial investment and operation cost and easy formation of secondary pollution. When the temperature of the selective catalytic reduction denitration reaction is 250-450 ℃, the denitration rate can reach 70% -90%. The technology is mature and reliable, and is widely applied in the world, particularly in developed countries, but the process equipment investment is large, the flue gas needs to be preheated, the catalyst is expensive and has short service life, and meanwhile, the problems of ammonia leakage, easy corrosion of equipment and the like exist. The selective non-catalytic reduction temperature area is 870-1200 ℃, and the denitration rate is less than 50%. The disadvantages are large investment of process equipment, need of preheating treatment of flue gas, easy corrosion of equipment and the like.

Disclosure of Invention

The invention aims to solve the technical problems and provides a high-efficiency biological agent desulfurization and denitrification process.

In order to solve the technical problems, the technical scheme provided by the invention is as follows: a high-efficiency biological agent desulfurization and denitrification process comprises the following steps:

the method comprises the following steps: sending the waste gas containing sulfur and nitrogen to a dust removal device by a fan for dust removal, and cooling the waste gas after dust removal by using a heat exchanger;

step two: respectively enabling microorganisms and nutrient ingredients thereof to exist in a liquid phase to form a denitrogenation microbial inoculum liquid phase and a desulfurizer liquid phase, wherein the denitrogenation microbial inoculum liquid phase and the desulfurizer liquid phase form a composite microbial inoculum, the waste gas is fully contacted with the composite microbial inoculum in a biological scrubber, and pollutants in the waste gas are discharged after being purified by the microorganisms;

step three: humidifying the waste gas, then introducing the waste gas into a biological filter bed, transferring pollutants in the waste gas from a gas phase to the surface of a biological membrane, purifying the pollutants by microorganisms, and then discharging the pollutants.

Further, the liquid-phase strain of the denitrifier in the second step is one or more of achromobacter, alcaligenes, bacillus, chromobacterium and corynebacterium, and the desulfurizing bacteria of the desulfurizing agent liquid phase is one of vibrio desulfurizati, thiobacillus thiooxidans and thiobacillus ferrooxidans.

Further, the biological scrubber in the second step is a spray tower or a bubble tower.

Further, the temperature of the exhaust gas cooled by the heat exchanger in the step one is below 30 ℃.

Furthermore, the biological filter bed consists of a filter material bed layer, a gravel layer and a porous air distribution pipe, wherein the porous air distribution pipe is arranged in the gravel layer, and the filter material bed layer is filled with bioactive fillers.

Compared with the prior art, the invention has the advantages that: using suitable denitrifying bacteria to remove NO by using NOx as nitrogen source under the condition of external carbon source_xReduction to the most substantially harmless N₂The denitrifying bacteria can grow and propagate; the sulfur oxides in the flue gas are removed by utilizing the metabolism process of the chemoautotrophic microorganisms to SOx, and pollutants in an oxidation state such as SO are removed in the biological desulfurization process₂And sulfate, sulfite and thiosulfate are reduced by microorganisms to generate elemental sulfur and are removed.

The environmental condition and the operation condition of the microorganism are easy to control, the secondary pollution is not easy to occur, and the purification effect is good.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention more apparent, the present invention is further described in detail below with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The flue gas of the following examples is from simulated flue gas generated by a gas generating device, and the simulated flue gas is firstly introduced into a mixing device to mix the simulated flue gas with air before entering the synchronous desulfurization and denitrification treatment.

The first embodiment is as follows:

the method comprises the following steps: sending the waste gas containing sulfur and nitrogen to a dust removal device by a fan for dust removal, cooling the waste gas after dust removal by using a heat exchanger, and controlling the temperature of the waste gas at 40 ℃;

step two: respectively enabling microorganisms and nutrient ingredients thereof to exist in a liquid phase to form a denitrogenation microbial inoculum liquid phase and a desulfurizer liquid phase, wherein the denitrogenation microbial inoculum liquid phase and the desulfurizer liquid phase form a composite microbial inoculum, the denitrogenation microbial inoculum liquid phase is selected from alcaligenes, the desulfurizer liquid phase is selected from thiobacillus ferrooxidans, waste gas is fully contacted with the composite microbial inoculum in a biological scrubber, the biological scrubber is selected from a spray tower, and the spraying amount is 80m³/(m²H), the reaction time is 36 h;

step three: humidifying the waste gas, enabling the waste gas to enter a biological filter bed after the humidity reaches 20-30%, filling spherical-like ceramsite with the diameter of 1-1.5 cm into a filter material bed layer of the biological filter bed, transferring pollutants in the waste gas from a gas phase to the surface of a biological membrane, purifying the pollutants by microorganisms, and then discharging the pollutants.

As a result: detecting the concentration of sulfur dioxide and nitrogen oxide in the outlet waste gas after running for 1 period; through detection, the removal rate of the sulfur dioxide concentration is 90-95%; the removal rate of the nitrogen oxide is 70-90%.

Example two:

the method comprises the following steps: conveying the waste gas containing sulfur and nitrogen to a dust removal device by a fan for dust removal, cooling the waste gas after dust removal by using a heat exchanger, and controlling the temperature of the waste gas at 30 ℃;

step two: respectively enabling microorganisms and nutrient ingredients thereof to exist in a liquid phase to form a denitrogenation microbial inoculum liquid phase and a desulfurizer liquid phase, wherein the denitrogenation microbial inoculum liquid phase and the desulfurizer liquid phase form a composite microbial inoculum, the denitrogenation microbial inoculum liquid phase is Achromobacter, the desulfurizer liquid phase is vibrio desulfurization, waste gas is fully contacted with the composite microbial inoculum in a biological scrubber, the biological scrubber is selected from a spray tower, and the spraying amount is 50m³/(m²H), the reaction time is 24 h;

step three: humidifying the waste gas, enabling the waste gas to enter a biological filter bed after the humidity reaches 20-30%, filling materials filled in a filter material bed layer of the biological filter bed are made of porous acid-resistant plastic materials with the diameter of 80-100mm, and discharging pollutants in the waste gas after the pollutants are transferred to the surface of a biological membrane from a gas phase and purified by microorganisms.

As a result: detecting the concentration of sulfur dioxide and nitrogen oxide in the outlet waste gas after running for 1 period; through detection, the removal rate of the sulfur dioxide concentration is 95-100%; the removal rate of the nitrogen oxide is 80-96%.

Comparative example:

the method comprises the following steps: conveying the waste gas containing sulfur and nitrogen to a dust removal device by a fan for dust removal, cooling the waste gas after dust removal by using a heat exchanger, and controlling the temperature of the waste gas at 30 ℃;

step two: respectively enabling microorganisms and nutrient ingredients thereof to exist in a liquid phase to form a denitrogenation microbial inoculum liquid phase and a desulfurizer liquid phase, wherein the denitrogenation microbial inoculum liquid phase and the desulfurizer liquid phase form a composite microbial inoculum, the denitrogenation microbial inoculum liquid phase is Achromobacter, the desulfurizer liquid phase is vibrio desulfori, waste gas is fully contacted with the composite microbial inoculum in a biological scrubber and then discharged, the biological scrubber is a spray tower, the spraying amount is 50m3/(m2 h), and the reaction time is 24.

As a result: detecting the concentration of sulfur dioxide and nitrogen oxide in the outlet waste gas after running for 1 period; through detection, the removal rate of the sulfur dioxide concentration is 70-85%; the removal rate of the nitrogen oxide is 60-80%.

In the technical scheme, the biological filter bed is additionally arranged in the spraying of the biological agent, and the results of the examples 1-2 and the comparative example 1 show that the desulfurization and denitrification effects are better, and the waste gas purification is more thorough.

The present invention and the embodiments thereof have been described above, but the description is not limited thereto, and the embodiments shown in the examples are only one of the embodiments of the present invention, and the actual structure is not limited thereto. In summary, those skilled in the art should appreciate that they can readily use the disclosed conception and specific embodiments as a basis for designing or modifying other structures for carrying out the same purposes of the present invention without departing from the spirit and scope of the invention as defined by the appended claims.