CN101011591A

CN101011591A - Method and apparatus for treating malodorous gas by using composite microorganism and nano composite carrier

Info

Publication number: CN101011591A
Application number: CNA2007100730771A
Authority: CN
Inventors: 张涉; 马辉文
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-02-05
Filing date: 2007-02-05
Publication date: 2007-08-08

Abstract

The invention relates to a method for using composite microbe and nanometer composite carrier to treat the gas with bad smell, and relative device. The box of biological filter is divided by several upright baffle plates, which contains microbe nourishment storage pool, a liquid level controller, a porous baffle plate, a nourishment spray tube, and a nourishment circulate pump, while the bad smell flows in the box to contact with the nanometer composite mineral carrier stacked on the porous baffle plate, to degrade the object via the microbe group on/in the nanometer composite mineral carrier into the material without toxicity and harm, as water, carbon dioxide, nitrogen gas and sulfur. And the invention uses the bad smell object as the carbon source, energy source, nitrogen source and sulfur source of microbe to realize circulation, save cost and reduce nourishment consumption. The invention has simple structure and low cost, while the LQ-SSB composite microbe group and nanometer composite mineral carrier have high stability and efficiency.

Description

Method and device for treating malodorous gas by using composite microorganisms and nano composite carrier

The technical field is as follows:

the invention belongs to the technical field of removing malodorous gases generated by municipal domestic wastes and sludge of residential septic tanks, and particularly relates to a biological deodorization treatment method and a device. It can be used for removing malodorous gas generated in the treatment process of municipal domestic garbage and municipal fecal residue sludge.

Background art:

along with the enhancement of the environmental awareness of people, the requirement on the environmental quality is improved, and the pollution to malodorous gas is more sensitive. The substances generating the malodors can not only cause people to feel uncomfortable and aversive, but also harm the health and even life of people, and particularly, malodorous gas substances such as ammonia, hydrogen sulfide, methyl mercaptan, lower fatty acid, amines and the like generated by decomposing urban domestic garbage and excrement sludge become serious environmental pollutants. Therefore, when the municipal solid waste and the municipal fecal residue sludge are transported and treated, effective removal and control measures are taken against the malodorous gases generated by the municipal solid waste and the municipal fecal residue sludge.

The currently applied malodorous gas treatment methods mainly comprise a neutralization method, an incineration method, a water washing method, an activated carbon adsorption method, a high-temperature oxidation method, a chemical method, an activated sludge oxidation method and a biological filtration method. In the neutralization method, the neutralizing agent is a compound which can react with odor-presenting substances in the malodorous gas to eliminate the odor-presenting function of the malodorous gas. The neutralizing agent is sprayed to eliminate malodorous gas when or before the malodorous gas is expected to be generated. But the uncertainty factor is many and is not easy to control. The burning method has the advantages of high efficiency of removing the odor pollution, simplicity, easy operation, certain heat value of the odor and no consumption of a large amount of fuel in the burning process. However, the method has the disadvantages of large equipment investment, high running cost and possibility of generating secondary pollution. The water washing method can effectively remove the gas with good water solubility, but the water adsorbed with the odor substance needs to be further treated because the nature of the odor substance is not changed by the treatment method. In the process of treating malodorous gas by chemical method, the malodorous substance in the malodorous gas is removed by using an aqueous solution containing chemical drugs capable of absorbing, neutralizing and oxidizing the malodorous substance. However, this method requires a large amount of chemical agents, and is expensive to operate, and the produced wastewater needs to be separately treated. When activated carbon is used for adsorption deodorization, the activated carbon has a limited adsorption capacity, cannot be regenerated after consumption and needs to be refilled, and is easy to clog, and the like, so that the method cannot be used as a main odor treatment method. The high-temperature oxidation method is to treat odor at 760 ℃ for one second to oxidize odor-causing substances. The equipment investment and the operation cost of the method are high, and the deodorization efficiency of the method is not different from that of other methods. The principle of removing odor substances by using an activated sludge oxidation method is that the odor substances are absorbed and decomposed by microorganisms in activated sludge in a sludge oxidation pond of a sewage treatment plant. However, the malodorous gas is generated at a place which is far away from a sewage treatment plant, and the investment on equipment for delivering the malodorous gas over a long distance is too large. The biological filtration method is used for intercepting odor-presenting substances in odor by means of adsorption of solid fillers wetted by nutrient solution containing microorganisms in a biological deodorization device. The latter are degraded again by the microorganisms therein. Compared with the traditional deodorization technology, the biological filtration method has the advantages of low cost, high efficiency, capability of treating various pollutants simultaneously and the like. Has better treatment effect on various volatile organic compounds which are difficult to degrade, and is a current and internationally popular odor treatment method. However, this odor treatment method also has the following disadvantages: firstly, the microorganisms used in such biofiltration devices have not been specifically screened and acclimated, and the deodorizing effect is not yet satisfactory; secondly, the formula of the nutrient solution is set only according to the growth needs of the microorganisms, and odor substances are not considered and can be used as nutrient substances by the microorganisms, so that the nutrient solution is eutrophicated due to overgrowth of the microorganisms, and the nutrient solution needs to be updated regularly. Not only does this increase the operating cost, but also it needs to be disposed of to eliminate the pollution of the replaced eutrophic nutrient solution to the environment; thirdly, such biofiltration devices do not provide the required special ecological environment for each type of microorganism involved in the removal of odoriferoussubstances. This not only fails to fully exert the deodorizing ability of microorganisms, but also aggravates the enrichment of nutrient solutions.

The invention content is as follows:

the invention relates to a method and a device for biological deodorization treatment. In order to achieve the purpose of efficiently removing malodorous gases, the structure and the deodorization process of the novel biological deodorization treatment device are as follows:

it is a box-shaped body made of stainless steel plates or PVC plates. The size and the structure of the box body are designed to ensure that the retention time of the malodorous gas in the box body is not less than 20 seconds; the flow velocity of the malodorous gas in the box body is less than 1 m/s; the total airflow resistance of the box body is not more than the air pressure of an exhaust fan for pressing and conveying the malodorous gas. The box body is divided into a plurality of parts which are communicated in a vertically staggered manner by vertical partition plates (2) in a vertically staggered manner so as to increase the retention time of the malodorous gas in the biological deodorization device. The bottom of the device is provided with a liquid storage tank (3) filled with microorganism nutrient solution (8), and the device is provided with a liquid level controller (4) which can supplement evaporated moisture in time. LQ-SSB complex microbial flora is put into the nutrient solution (see the Chinese patent 03140360.3). A porous shelf (5) is arranged at a position with a certain height away from the bottom of the box body, and porous plastic balls (9) with a certain height and nano composite mineral carriers (see Chinese patent 03140183.X) are stacked on the porous shelf; ammonia, hydrogen sulfide, sulfhydryl compounds, amine compounds, lower fatty acid andaldehyde are used as foul gas which is mainly odorous, and the foul gas is pressurized by an odor suction and exhaust fan (1) and then is introduced from an air inlet positioned between a nutrient solution surface (8) and a porous shelf (5). In order to reduce the power consumption as much as possible, the design scheme of the novel deodorization biological deodorization device is as follows: the air exhaust fan (1) can adopt a horizontal air exhaust mode to reduce the wind resistance of the pipeline. The connecting pipe between the biological deodorization device and the connecting pipe can be a round (square) square transition pipe, the sectional area of the connecting part of the connecting pipe and the air inlet of the box body is equal to the sectional area of the air inlet of the box body and is slightly larger than the sectional area of the odor collecting pipe. A nutrient solution spray pipe (7) is arranged in the upper space of the box body, and microorganism nutrient solution (8) filled in a liquid storage tank (3) of the nutrient solution is sprayed on the surface of a porous plastic ball (9) filled with the nano composite mineral carrier in a fogdrop mode through a nutrient solution circulating pump (6) and the nutrient solution spray pipe (7). After the odor collides and contacts with the stacked nano composite mineral carrier (9) and the falling nutrient solution fog drops through the porous shelf (5), the odorous substances in the odor are absorbed by nitrifying bacteria, denitrifying bacteria, hydrogen sulfide oxide bacteria and other microorganisms in the LQ-SSB composite microbial flora attached to the sprayed nutrient solution (8) and the nano composite mineral carrier (9), and are converted into water, carbon dioxide, nitrogen and elemental sulfur by the microorganisms in the biochemical conversion process shown in the following figure under the condition that the peculiar ecological environment is created by the deodorization biological deodorization device.

Organic acid, ketone, aldehyde → water + carbon dioxide

The nutrient solution added in the biological deodorization treatment device disclosed by the invention has the following formula (each liter of nutrient solution water contains): 4-10 g of monopotassium phosphate, 1.5-0.2 g of sodium dihydrogen phosphate, 100 mg of magnesium sulfate heptahydrate and 0.05-0.2 mg of copper sulfate pentahydrate. The pH of the nutrient solution was adjusted to 7.4 with 10 molar sodium hydroxide solution. During the operation, tap water is added according to the evaporation amount of water.

Compared with the prior deodorization technology, the novel biological deodorization treatment method disclosed by the patent has the following obvious advantages:

1. the LQ-SSB composite microbial flora and the nano composite mineral carrier show high stability and effectiveness in the processes of garbage collection and transportation stations, deodorization of environment-friendly ecological toilets and sewage treatment through years of practical application;

2. the deodorization process of the traditional biological deodorization treatment device is changed, the equipment is simple, and the investment is small;because the equipment is reduced, the power consumption is also reduced;

3. the microorganisms in the biological deodorization treatment device utilize the odor-presenting substances as carbon sources, energy sources and nitrogen sources for the growth and substance conversion of the odor-presenting substances. The nutrient solution contains only limited trace elements required for the growth of microorganisms. Therefore, the growth of microorganisms in the biological deodorization treatment device is limited, nutrient solution enrichment is not caused, and the sewage discharge is not feared.

Description of the drawings:

the attached drawing is a schematic diagram of the biological deodorization treatment device of the patent:

in the figure, the device comprises an air exhaust fan 1, a vertical partition plate 2, a liquid storage tank 3, a liquid level controller 4, a porous shelf 6, a nutrient solution circulating pump 7, a nutrient solution spray pipe 8, a microorganism nutrient solution 9 and a nano composite mineral carrier.

The specific implementation mode is as follows:

example one:

the biological deodorization treatment device is made into a box body by a PVC plate. The retention time of the malodorous gas in the box body is 30 seconds; the flow velocity of the malodorous gas in the box body is 0.5 m/s; the total airflow resistance of the box body is equal to the air pressure of an exhaust fan which pumps the malodorous gas. The box body is divided into four parts which are communicated in a vertically staggered manner by vertical partition plates (2)in a vertically staggered manner. The bottom of the device is provided with a liquid storage tank (3) filled with microorganism nutrient solution, and a liquid level controller (4) is arranged to supplement evaporated moisture in time. LQ-SSB compound microbial flora is put into the nutrient solution. A porous shelf (5) is arranged at a certain height away from the bottom of the box body, and porous plastic balls (9) filled with nano composite mineral carriers are stacked at a certain height on the porous shelf; ammonia, hydrogen sulfide, sulfhydryl compounds, amine compounds, lower fatty acid and aldehyde are used as foul gas which is mainly odorous, and the foul gas is pressurized by an odor suction and exhaust fan (1) and then is introduced from an air inlet positioned between a nutrient solution surface (8) and a porous shelf (5). The air exhaust fan (1) adopts a common air exhaust mode. The connecting pipe between the biological deodorization device and the connecting pipe is a standard transition pipe, the sectional area of the connecting part of the connecting pipe and the air inlet of the box body is equal to the sectional area of the air inlet of the box body and is slightly larger than the sectional area of the odor collecting pipe. A nutrient solution spray pipe (7) is arranged in the upper space of the box body, and microorganism nutrient solution (8) filled in a liquid storage tank (3) of the nutrient solution is sprayed on the surface (9) of the porous plastic ball filled with the nano composite mineral carrier in a fogdrop mode through a nutrient solution circulating pump (6) and the nutrient solution spray pipe (7).

The microbial nutrient solution is an inorganic salt solution prepared from tap water, and the formula of the inorganic salt solution is as follows (the content in each liter of the nutrient solution): 6 g of monopotassium phosphate, 1.3 g of sodium dihydrogen phosphate, 300 mg of magnesium sulfate heptahydrate and 0.2 mg of copper sulfate pentahydrate. The pH of the nutrient solution was adjusted to 7.4 with 10 molar sodium hydroxide solution. During the operation, tap water is added according to the evaporation amount of water.

Example two:

the biological deodorization processing device is made of a stainless steel plate into a box body. The retention time of the malodorous gas in the box body is 25 seconds; the flow velocity of the malodorous gas in the box body is 0.8 m/s; the total airflow resistance of the box body is smaller than the air pressure of an exhaust fan which is used for pressing and conveying the malodorous gas. The air exhaust fan adopts a horizontal air exhaust mode to reduce the wind resistance of the pipeline. The box body is divided into five parts which are communicated in a vertically staggered way by vertical partition plates (2) in a vertically staggered way so as to increase the retention time of the malodorous gas in the biological deodorization device. The bottom of the device is provided with a liquid storage tank (3) filled with microorganism nutrient solution, and a liquid level controller (4) is arranged to supplement evaporated moisture in time. LQ-SSB compound microbial flora is put into the nutrient solution. A porous shelf (5) is arranged at a certain height away from the bottom of the box body, and porous plastic balls (9) filled with nano composite mineral carriers are stacked at a certain height on the porous shelf; ammonia, hydrogen sulfide, sulfhydryl compounds, amine compounds, lower fatty acid and aldehyde are used as foul gas which is mainly odorous, and the foul gas is pressurized by a horizontal exhaust fan (1) for sucking and delivering odor and then is introduced from an air inlet positioned between a nutrient solution surface (8) and a porous shelf (5). The connecting pipe between the biological deodorization device and the connecting pipe is a round and square transition pipe, the sectional area of the connecting part of the connecting pipe and the air inlet of the box body is equal to the sectional area of the air inlet of the box body, and is slightly larger than the sectional area of the odor collecting pipe. A nutrient solution spray pipe (7) is arranged in the upper space of the box body, and microorganism nutrient solution (8) filled in a liquid storage tank (3) of the nutrient solution is sprayed on the surface (9) of the porous plastic ball filled with the nano composite mineral carrier in a fogdrop mode through a nutrient solution circulating pump (6) and the nutrient solution spray pipe (7).

The microbial nutrient solution is an inorganic salt solution prepared from tap water, and the formula of the inorganic salt solution is as follows (the content in each liter of the nutrient solution): 5 g of monopotassium phosphate, 1.0 g of sodium dihydrogen phosphate, 200 mg of magnesium sulfate heptahydrate and 0.1 mg of copper sulfate pentahydrate. The pH of the nutrient solution was adjusted to 7.3 with 10 molar sodium hydroxide solution. During the operation, tap water is added according to the evaporation amount of water.

Claims

1. The utility model discloses a device for malodorous gas is handled to compound microorganism and nanometer composite carrier, the structure of its box of its characterized in that, the box is crisscross by a plurality of vertical partition boards and separates, the bottom is microorganism nutrient solution liquid storage tank, be equipped with liquid level controller, apart from the porous baffle of the position installation of bottom half take the altitude, nanometer composite mineral carrier is stacked on upper portion, at box upper portion space installation nutrient solution shower, the microorganism nutrient solution of liquid storage tank passes through the nutrient solution circulating pump and sprays on nanometer composite mineral carrier with the form of droplet via the nutrient solution shower.

2. The method for treating malodorous gas by using composite microbe and nano composite carrier is characterized by its biochemical conversion process. Nitrifying bacteria, denitrifying bacteria, hydrogen sulfide oxidizing bacteria and other microorganisms in the microbial flora attached to and in the nano composite mineral carrier can absorb odor-forming substances and convert the odor-forming substances into water, carbon dioxide, nitrogen and elemental sulfur. Uses the odor-presenting substances as carbon source, energy source, nitrogen source and sulfur source of the microorganism.

3. The apparatus for treating malodorous gas by using composite microorganisms and nano-composite carriers as claimed in claim 1, wherein the size and structure of the box body are designed so that the retention time of malodorous gas in the box body is not less than 20 seconds; the flow velocity of the malodorous gas in the box body is less than 1 m/s; the total airflow resistance of the box body is not more than the air pressure of an exhaust fan for pressing and conveying the malodorous gas.

4. The method for treating malodorous gas by using composite microbe and nano composite carrier as claimed in claim 2, wherein the nutrient solution of microbe is inorganic salt solution prepared from tap water, and its formulation is (per liter of nutrient solution): 4-10 g of monopotassium phosphate, 0.2-1.5 g of sodium dihydrogen phosphate, 100 mg of magnesium sulfate heptahydrate and 0.05-0.2 mg of copper sulfate pentahydrate.