CN114045229A

CN114045229A - Directional amplification method for bioremediation indigenous microorganisms of rivers and lakes and application

Info

Publication number: CN114045229A
Application number: CN202111181562.7A
Authority: CN
Inventors: 王炜
Original assignee: Sponge City Construction Shanghai Co ltd
Current assignee: Sponge City Construction Shanghai Co ltd
Priority date: 2021-10-11
Filing date: 2021-10-11
Publication date: 2022-02-15
Anticipated expiration: 2041-10-11
Also published as: CN114045229B

Abstract

The invention relates to the technical field of environmental remediation and sewage treatment, in particular to a directional amplification method and application of indigenous microorganisms for river and lake bioremediation. The invention enriches and screens three indigenous microbial functional floras of nitrifying bacteria flora, aerobic heterotrophic flora and denitrifying bacteria flora by directional amplification, and is applied to water purification and ecological restoration of rivers and lakes by matching with technologies such as river aeration, bottom mud bioremediation and the like. The indigenous microbial preparation is taken from the bottom mud of the river channel, has strong adaptability, can be directly planted in functional microbial populations or communities of the ecological systems of the river channel and the lake, realizes high-efficiency water purification and bottom mud restoration, and has good effect persistence; the problems of biological safety, biological invasion, ecological risks and the like do not exist; the method has low production cost, can be widely applied to treatment of black and odorous riverways and water quality improvement of urban riverways, and realizes 'one river one policy' and 'one river one bacterium' by matching with technologies such as riverway aeration, bottom mud bioremediation and the like according to specific conditions, thereby improving the treatment efficiency of the riverways.

Description

Directional amplification method for bioremediation indigenous microorganisms of rivers and lakes and application

Technical Field

The invention relates to the technical field of environmental remediation and sewage treatment, in particular to a directional amplification method for bioremediation indigenous microorganisms in rivers and lakes and application.

Background

At present, the method for maintaining and repairing the water quality of the river channel mainly comprises a physical method, a chemical method and a biological method, wherein the physical method comprises the steps of aerating the river channel, salvaging, putting in an adsorbent, shielding bottom mud, changing water and diluting, and the like, so that the method has the advantages of large investment, high operating cost and difficulty in persistence; the chemical method mainly comprises the steps of adding chemical agents such as an oxidant, a flocculating agent, a curing agent and the like into rivers and lakes, so that a large secondary pollution risk exists; the bioremediation is to put microbial agents or microbial growth promoters, enzyme preparations and the like into the water body or the bottom mud, so as to strengthen the degradation of the microorganisms to pollutants, enhance the self-cleaning capability of rivers and lakes and maintain the clean aerobic ecosystem of the rivers. Bioremediation is an in-situ remediation technology, does not need large-scale engineering, has small investment, high efficiency, environmental friendliness and no secondary pollution, and is successfully applied to pollution treatment of soil, underground water, river channels and offshore ocean surfaces.

The bioremediation technology mainly comprises a biological strengthening technology and a biological growth promoting technology, wherein the biological strengthening technology emphasizes direct addition of a microbial preparation, and the biological growth promoting technology emphasizes a microbial growth promoter and a complex enzyme preparation, stimulates the growth of indigenous microorganisms, strengthens the degradation of pollutants and improves the water quality. In practical engineering application, the two are combined together, so that microorganisms are put in to increase and efficiently degrade the biomass of the microorganisms, and growth promoting agents are also put in to create favorable environmental conditions for the propagation and degradation of the microorganisms so as to accelerate the bioremediation process. Most of microbial preparations adopted by the biological strengthening technology are exogenous screening, even microbial preparations constructed by adopting a biological engineering means have the problem of biological safety, exogenous microorganisms are thrown into water, usually cannot compete with indigenous microorganisms, are difficult to fix and have strong functions and difficult lasting effect. The indigenous microorganisms have unique advantages which are not possessed by exogenous microorganisms in water environment treatment, are sourced from bottom mud of rivers and lakes to be treated, are the result of long-term selection in the nature, the metabolic activity of the indigenous microorganisms directly influences the water environment material circulation and ecological balance, and are completely adaptive to the environment, once the indigenous microorganisms are stimulated to reproduce or are amplified to a certain population number, the water quality purification function can be effectively exerted, and the exogenous microorganisms are commercial products screened, separated and amplified in a laboratory, have lower adaptability to the natural environment than the indigenous microorganisms and are difficult to be fixedly planted in the natural environment; the transformation of natural substances is completed by the synergistic action of various functional indigenous microbial populations or communities, and the exogenous microbes are only functional microbial populations consisting of one or more microbes. However, the conventional method for expanding and culturing indigenous microorganisms usually adopts laboratory screening, separation and amplification procedures, and is also only directed to certain functional microorganisms, so that a specific functional microbial flora or community is difficult to select, and the function of the method in the bioremediation engineering is limited to a certain extent. Patent CN10739981213B adopts Thiobacillus denitrificans powder, composite bacillus powder, composite yeast powder and the like to prepare a composite microbial preparation for treating black and odorous rivers, which can quickly improve the water quality of the black and odorous rivers and remove black and odorous sediment, but exogenous microbial strains cultured in laboratories have better effect than single strains, but the exogenous microbes are difficult to adapt to natural rivers and plant into functional populations or communities of natural ecosystems, and the water quality purification effect is difficult to persist; the patent with application number 201911022181.7 discloses a method for enrichment culture of indigenous nitrogen-converting microorganisms and application of the method in treatment, which comprises the steps of collecting sediment at different positions of a river channel to be treated, transferring the sediment to a nitrogen-converting microorganism enrichment culture medium to prepare a certain amount of nitrogen-converting microorganisms, obtaining a conversion matrix through 3-5 times of transfer culture, putting the conversion matrix into a culture tank for amplification to achieve an indigenous microorganism preparation, and testing the treatment effect through river water. However, the indigenous nitrogen-transformed microbial preparation prepared by the scheme is mainly aimed at nitrogen transformation, and nitrogen transformation in natural water is actually a complex process, and is at least designed to nitrify and denitrify two types of microbial communities, the two types of microbial communities are completely different in selection mode and enrichment medium, so that the two types of functional microbial communities (nitrifying bacteria are autotrophic bacteria and denitrifying bacteria are facultative heterotrophic bacteria) are difficult to produce simultaneously in a selection culture system, and each sampling point is screened and cultured separately and is difficult to enrich to the required functional microbial communities; the patent with application number 201910101603.3 discloses a method for efficiently removing ammonia nitrogen from a water body by culturing indigenous microorganisms, wherein sediment or coated fillers collected from a target river channel are dissolved in the target water body and then screened, secondary culture media are added for respectively carrying out in-situ aeration culture for 24-48 h and 24h so as to enrich the indigenous microorganisms, and finally bacterial liquid obtained by culture is added into the target river channel. The method needs to be developed for directionally amplifying indigenous microorganisms used for biological restoration of rivers and lakes, and microbial populations or communities with different indigenous functions suitable for river water bodies and bottom mud are amplified according to the requirements of water quality purification indexes in the ecological restoration of rivers and lakes.

Disclosure of Invention

The invention aims to provide a directional amplification method and application for bioremediation of indigenous microorganisms in rivers and lakes, aiming at the problems of environmental adaptability, biosafety, high price, single population, poor effect persistence and the like of exogenous microbial preparations and the problems that the production process of indigenous microbial preparations is usually aimed at single-function microorganisms, and the problems that directional amplification and functional microbial population or community enrichment screening are not available, the application efficiency is low and the like. The invention aims to enrich and screen out three indigenous microbial functional floras such as nitrifying bacterial flora, aerobic heterotrophic flora and denitrifying bacterial flora with strong functions by directional amplification according to the water quality purification indexes of rivers and lakes, and is applied to water quality purification and ecological restoration of the rivers and lakes by matching with technologies such as river aeration, sediment biological restoration and the like.

The indigenous microbial preparation is taken from the bottom mud of the river channel, has strong adaptability, can be directly planted in functional microbial populations or communities of the ecological systems of the river channel and the lake, realizes high-efficiency water purification and bottom mud restoration, and has good effect persistence; the problems of biological safety, biological invasion, ecological risks and the like do not exist; the method has low production cost, can be widely applied to treatment of black and odorous riverways and improvement of urban riverway water quality, and realizes 'one river one policy' and 'one river one bacterium' by matching with technologies such as riverway aeration, bottom mud bioremediation and the like according to specific conditions of riverways and lakes, thereby improving the treatment efficiency of the riverways.

The technical concept of the invention is as follows:

the microbial flora related to the water quality purification of the riverways and the lakes mainly comprises three functional microbial populations or communities, namely nitrifying bacteria flora, denitrifying bacteria flora, aerobic heterotrophic microbial flora and the like. The nitrifying bacteria flora is mainly used for removing ammonia nitrogen in water; the denitrifying bacteria flora is mainly used for denitrifying the anaerobic layer of the bottom mud in the river to remove organic matters in the bottom mud and the intermittent water of the bottom mud, and is generally matched with calcium nitrate for use; the aerobic heterotrophic microorganism flora is mainly used for removing organic matters in water or bottom sludge, and oxygen is used as an electron acceptor, so that the aerobic heterotrophic microorganism flora is used in combination with aeration, calcium peroxide and other oxygenation measures. Aiming at three functional microbial populations or communities such as nitrobacteria flora, denitrifying bacteria flora, aerobic heterotrophic microbial flora and the like, a functional indigenous microbial flora enrichment culture medium is designed, riverway and lake sediment to be treated is used as an indigenous microbial provenance, the required functional microbial flora is enriched and screened under the aeration (nitrobacteria flora and aerobic heterotrophic microbial flora) or stirring (denitrifying bacteria flora) condition, the cultured indigenous microbial flora is put into the collected treated riverway river water for testing, the water quality purification capacity of the functional indigenous microbial flora is determined, and three functional indigenous microbial flora protospecies are formed by flocculation precipitation, functional microbial flora concentration and secondary culture concentration. Adding the functional indigenous microbial community stock into a culture tank, adding a corresponding expanded culture medium, and carrying out large-scale culture on indigenous nitrogen-converted microorganisms to finally form three functional indigenous microbial community products, wherein the liquid product can be directly used for improving the water quality of rivers and lakes, and if the liquid product is required to be used for substrate sludge remediation, a solid loading agent and a binder can be added, and tabletting and granulating are carried out to prepare a substrate sludge remediation microbial preparation product.

The invention adopts functional indigenous microbial flora enrichment culture medium, takes riverway and lake bottom mud to be treated as indigenous microbial provenance, enriches and screens three functional microbial populations or communities of required nitrifying bacterial flora, denitrifying bacterial flora, aerobic heterotrophic microbial flora and the like under the condition of aeration (nitrifying bacterial flora and aerobic heterotrophic microbial flora) or stirring (denitrifying bacterial flora), concentrates the functional microbial flora through flocculation precipitation, and forms three functional indigenous microbial flora stocks through secondary concentration and culture. Adding the functional indigenous microbial community protospecies into a culture tank, adding a corresponding expanded culture medium, and carrying out large-scale culture on the functional indigenous microbial community to finally form three functional indigenous microbial community products, wherein the liquid products can be directly used for improving the water quality of rivers and lakes; if the microbial preparation is required to be used for bottom sediment remediation, a solid loading agent, a counterweight agent and a binder can be added, and the microbial preparation product for bottom sediment remediation can be prepared by tabletting and granulating.

The purpose of the invention can be realized by the following technical scheme:

the invention aims to provide a method for directionally amplifying indigenous microorganisms for biological repair of rivers and lakes, which comprises the following steps:

(1) bottom mud collection and cleaning: collecting bottom mud from rivers and lakes, and cleaning and removing garbage and sand in the bottom mud;

(2) enrichment culture: carrying out primary culture on the cleaned substrate sludge obtained in the step (1) through an enrichment medium to obtain first indigenous microorganisms, and screening 2-3 groups of the first indigenous microorganisms;

(3) and (3) secondary culture: taking the first indigenous microorganism stock screened in the step (2) as a strain, adding an enrichment medium again for secondary culture to obtain a second indigenous microorganism stock;

(4) and (3) amplification culture: and (4) adding the second original strain of the indigenous microorganisms obtained in the step (3) into an amplification culture medium, and culturing by using a culture tank to finally form a functional indigenous microbial flora product.

In one embodiment of the invention, the indigenous microorganisms used for the bioremediation of rivers and lakes comprise nitrifying bacterial flora, denitrifying bacterial flora and aerobic heterotrophic bacterial flora.

In one embodiment of the invention, in the step (1), the bottom mud 20-40mm below the mud-water interface is collected, and the particles of the bottom mud are less than 25 μm.

In one embodiment of the present invention, in step (2), the nitrobacteria flora enrichment medium comprises the following components, ratio and culture mode:

the culture mode is as follows: aerating until dissolved oxygen is kept above 4mg/l, and adding calcium carbonate to keep pH at 7-8; culturing for 3-7 days.

In one embodiment of the present invention, in step (2), the denitrifying bacteria flora enrichment medium comprises the following components, ratio and culture mode:

the culture mode is as follows: culturing under stirring for about 15 days until pH is reduced to 3-4.

In one embodiment of the present invention, in step (2), the aerobic heterotrophic bacteria flora enrichment medium comprises the following components, ratio and culture mode:

the culture mode is as follows: aerating until dissolved oxygen is kept above 4mg/l, adding calcium carbonate to keep pH at 7-7.3, and culturing for 3-5 days.

In one embodiment of the present invention, in step (2), the screening is a screening of a high efficiency microbial flora, that is,

adding glucose and dipotassium hydrogen phosphate into river water to ensure that the COD of the river water is 200-300mg/l and the TP of the river water is 3-7mg/l, and adopting aeration treatment to screen high-efficiency aerobic heterotrophic bacteria;

replacing glucose with ammonium sulfate to make ammonia nitrogen 30-50mg/l, and performing aeration treatment to screen out high-efficiency functional nitrifying bacteria flora;

adding sodium nitrate into the river water to replace ammonium sulfate to ensure that the concentration of nitrate nitrogen is 30-50mg/l, simultaneously adding glucose to ensure that the COD of the river water reaches 100-200mg/l, and adopting stirring treatment to screen out denitrifying bacteria flora.

And taking the three screened functional indigenous microbial floras as strains, adding the corresponding concentrated culture medium again, and carrying out secondary culture.

In one embodiment of the invention, in the step (2), after the nitrifying bacteria flora in the bottom sediment is subjected to primary culture by the enrichment medium, flocculation, precipitation and concentration are further performed, that is, a PAM flocculating agent is added to precipitate and concentrate the nitrifying bacteria flora to obtain a concentrated solution; and using the concentrated solution as a first stock of nitrobacteria flora;

in the step (3), after the first stock species of the nitrifying bacteria flora is subjected to secondary culture by the enrichment medium, performing flocculation, precipitation and concentration, namely adding a flocculating agent to precipitate and concentrate the nitrifying bacteria flora to obtain a concentrated solution; and using the concentrate as a second stock of nitrifying bacterial flora.

In one embodiment of the present invention, in step (4), the nitrobacteria flora expanding medium comprises the following components, ratio and culture mode:

the culture mode is as follows: aerating until dissolved oxygen is kept above 4mg/l, adding calcium carbonate to keep pH at 7-8, and culturing for 3-7 days.

In one embodiment of the present invention, in step (4), the denitrifying bacteria flora expanding medium comprises the following components, proportion and culture mode:

the culture mode is as follows: culturing under stirring for 10-20 days.

In one embodiment of the present invention, in step (4), the aerobic heterotrophic bacteria flora expanding medium comprises the following components, ratio and culture mode:

the culture mode is as follows: aerating until dissolved oxygen is kept above 4mg/l, adjusting pH to 7-7.3, and culturing for 3-10 days.

The invention also aims to provide application of the indigenous microbial community product for biological remediation of rivers and lakes, wherein the indigenous microbial community product is used for improving the water quality of a river water body or remedying bottom mud of the river.

In one embodiment of the invention, the prepared three functional indigenous microbial community products can be directly used for the water quality of the river channel water body and can also be used for restoring bottom mud of the river channel.

When the composite material is used for bottom sediment repair, 80% of zeolite powder, 0.5% of chitosan glacial acetic acid solution and 20% of diatomite are added into a nitrifying bacteria indigenous microbial community product, and the mixture is uniformly mixed and pressed into tablets with the diameter of 10mm and the height of 4mm, and the tablets are used for repairing bottom sediment on the surface layer of a river bottom sediment mud-water interface; adding 80% of zeolite powder, 0.5% of chitosan glacial acetic acid solution and 20% of diatomite into an aerobic heterotrophic bacteria indigenous microbial community product, uniformly mixing, and pressing into tablets with the diameter of 10mm and the height of 4mm, wherein the tablets are used for repairing bottom mud on the surface layer of a river bottom mud-water interface; adding 40% of zeolite powder, 0.5% of chitosan glacial acetic acid solution and 60% of sand grains into a denitrifying bacteria indigenous microbial community product, uniformly mixing, pressing into tablets with the diameter of 20mm and the height of 20mm, and using the tablets for repairing bottom mud at a bottom mud-water interface of river sediment.

In one embodiment of the present invention, the substrate is,

compared with the prior art, the invention has the following beneficial effects:

(1) the microorganism source in the invention is from the sediment of the riverway and the lake to be treated, belongs to indigenous microorganisms, avoids the introduction of external strains, and has no biological safety problem and ecological risk.

(2) The indigenous microorganisms have strong adaptability to the treatment of rivers and lakes, can be rapidly planted in a river and lake ecological system, purify water quality, repair bottom mud, and have high efficiency and sustainability.

(3) The method realizes the directional amplification of indigenous microorganisms by the formula of an enrichment medium and the adjustment of a microorganism culture process, specifically enriches and screens three functional indigenous microorganism flora products such as nitrifying bacteria flora, denitrifying bacteria flora, aerobic heterotrophic bacteria flora and the like, and applies the products to river and lake treatment.

(4) According to the method, indigenous microorganisms taken from the local environment are cultured in stages, concentrated functional indigenous microorganism protospecies are obtained through secondary enrichment culture, and then the concentration of bacterial liquid is ensured through propagation culture in a constant-temperature culture tank, so that the treatment effect of the bacterial liquid on a water body when the bacterial liquid is actually applied to a target river or lake is improved.

(5) The indigenous microorganisms take particles with the particle size of less than 25 mu m of the primary sediment as carriers, the specific surface area of the carriers is large, and the immobilized microorganism biomass is high, so the removal rate of pollutants is high, the removal load is high, the effect maintenance time is long, the ecological environment of a target river channel can be rapidly improved, and the self-cleaning capability is improved.

(6) The prepared indigenous microorganism product can be directly put into water bodies of rivers and lakes, water purification is realized by combining measures such as aeration, ecological bank protection and the like, and the indigenous microorganism product can also be combined with growth promoting agents, weighting agents, bonding agents and the like to prepare a bottom mud repairing agent for repairing bottom mud of rivers.

Detailed Description

The invention provides an indigenous microorganism directional amplification method for river and lake bioremediation, which comprises the following steps:

(2) enrichment culture: carrying out primary culture on the cleaned substrate sludge obtained in the step (1) through an enrichment medium to obtain a first indigenous microorganism stock, wherein 2-3 groups of the first indigenous microorganism stock are selected;

In one embodiment of the invention, in the step (2), the screening is the screening of the high-efficiency microbial flora, namely, the river water is utilized, glucose and dipotassium hydrogen phosphate are added to ensure that the COD of the river water is 200-300mg/l and the TP is 3-7mg/l, and aeration treatment is adopted, so that the high-efficiency aerobic heterotrophic bacteria flora is screened; replacing glucose with ammonium sulfate to make ammonia nitrogen 30-50mg/l, and performing aeration treatment to screen out high-efficiency functional nitrifying bacteria flora;

in the step (3), after the first stock species of the nitrifying bacteria flora is subjected to secondary culture by an enrichment medium, performing flocculation, precipitation and concentration, namely adding a PAM flocculating agent to precipitate and concentrate the nitrifying bacteria flora to obtain a concentrated solution; and using the concentrated solution as a second stock species of nitrobacteria flora.

the culture mode is as follows: culturing under stirring for 10-20 days.

The invention provides an application of an indigenous microbial community product for bioremediation of rivers and lakes, wherein the indigenous microbial community product is used for restoring water quality of a river water body or bottom mud of the river.

In one embodiment of the invention, the three functional indigenous microbial community products can be directly used for the water quality of the river channel water body and also can be used for restoring bottom mud of the river channel.

The present invention will be described in detail with reference to specific examples.

And (3) screening the bottom sludge which is 20-40mm below a mud-water interface and collected from a river channel of Guangzhou by using 2mm and 25 mu m sieves, respectively removing garbage and sand in the bottom sludge, precipitating for 24h, and collecting sediments to obtain an indigenous microorganism provenance.

Example 1

This example provides a method for the directed amplification of indigenous nitrifying bacterial flora.

(1) Enrichment culture

Taking 10kg of river water, adding 1kg of the cleaned bottom mud of the river and the lake, adding a nitrobacteria flora enrichment culture medium for culture,

enrichment medium of nitrobacteria flora:

10kg of water were added: aerating until dissolved oxygen is kept above 4mg/l, adding calcium carbonate to keep pH at 7-8, culturing for 3-7d, adding 0.5mg/l flocculant when ammonia nitrogen in river water is reduced to below 20mg/l, precipitating, and collecting precipitate.

(2) Expanding culture

Adding the concentrate of the indigenous nitrobacteria flora protospecies into a corresponding expanding culture medium according to 10 percent, adding the concentrate into a 20kg culture tank, adding a corresponding concentrated culture medium, and carrying out large-scale culture on the functional indigenous microbial flora to finally form a functional indigenous microbial flora product.

Nitrifying bacteria flora expanding culture medium:

20kg of water were added:

aerating until dissolved oxygen is kept above 4mg/l, adding calcium carbonate to keep pH at 7-8, culturing for 3-7d, adding 0.5mg/l flocculant when ammonia nitrogen in river water is reduced to below 20mg/l, precipitating, and collecting precipitate.

(3) River Water treatment test

Taking 20kg of river water to be treated, adding a certain amount of ammonium chloride to ensure that the ammonia nitrogen concentration of the river water reaches 10mg/l, and adjusting the river water to be treated to be test river water; adding 100mg/l of liquid indigenous nitrobacteria flora concentrated solution, aerating to ensure that the dissolved oxygen of the river water reaches 4mg/l, taking a test river water without adding nitrobacteria as a control, and sampling every 12h to test ammonia nitrogen.

TABLE 1 river Water treatment test results

	0	12	24	36	48
						Indigenous microorganisms	10	4.2	1.3	0.7	0.3
Control	10	9.1	8.7	8.9	8.5

As can be seen from Table 1, the addition of indigenous nitrobacteria flora can significantly reduce the ammonia nitrogen in the river water, the ammonia nitrogen in the river water is reduced from 10mg/l to 1.3mg/l within 24 hours, the ammonia nitrogen reaches the standard of the earth surface 4, and the ammonia nitrogen in the river water is reduced to below 0.3mg/l within 48 hours. The concentration of ammonia nitrogen of the river water without adding the indigenous microorganisms is basically unchanged along with aeration, which shows that the indigenous nitrobacteria flora produced by the method can obviously reduce the ammonia nitrogen of the river water body,

example 2

This example provides a method for the directed amplification of indigenous denitrifying bacteria flora.

(1) Enrichment culture

Taking 10kg of river water, adding 1kg of the cleaned bottom mud of the river and the lake, adding a denitrifying bacteria flora enrichment culture medium for culture,

denitrifying bacteria flora enrichment medium: 10kg of water were added:

stirring, culturing for about 15 days until pH is reduced to 3-4, adding 0.5mg/l flocculant, precipitating, and collecting precipitate.

And putting all the sediments into a denitrifying bacteria flora enrichment medium, carrying out secondary culture, and obtaining denitrifying bacteria flora stock without concentration.

(2) Expanding culture

Adding the native denitrifying bacteria flora stock seed concentrated solution into a 20kg culture tank according to 20 percent of corresponding expanding culture medium, adding the corresponding concentrated culture medium, and carrying out large-scale culture on functional native microbial flora to finally form a functional native microbial flora product.

Denitrifying bacteria flora expansion medium: 20kg of water were added:

stirring, culturing for 10-20d, and obtaining denitrifying bacteria flora products when the pH value in river water is reduced to 3-4.

(3) River Water treatment test

Taking 20kg of river water to be treated, adding a certain amount of calcium nitrate to enable the nitrate nitrogen concentration to reach 20mg/l, adding a certain amount of glucose to enable the COD of the river water to reach 100mg/l, and adjusting the river water to be tested; adding 100mg/l of liquid indigenous denitrifying bacteria flora product, stirring, taking test river water without adding nitrifying bacteria as a control, and sampling every 6h to test COD.

TABLE 2 river Water treatment test results

	0	6	12	18	24
						Indigenous microorganisms	100	67.2	41.5	21.7	15.3
Control	100	93.1	87.2	88.7	83.4

As can be seen from the table 2, the addition of indigenous denitrifying bacteria flora can effectively utilize nitrate nitrogen to remove COD in the water body, the COD of the river water within 18 hours is reduced from 100mg/l to 21.7mg/l, the standard of the earth surface 4 is reached, and the ammonia nitrogen of the river water within 24 hours is reduced to below 15.3 mg/l. The COD concentration of the native microorganism river water is basically unchanged without adding the native microorganism river water, which shows that the native denitrifying bacteria flora produced according to the invention can obviously activate the denitrification reaction of the river channel, reduce the COD of the river channel water body and can be applied to the treatment of black and odorous river channels and the water quality improvement engineering of urban river channels.

Example 3

This example provides a method for the directed amplification of indigenous aerobic heterotrophic bacterial flora.

(1) Enrichment culture

Taking 10kg of river water, adding 1kg of the cleaned bottom mud of the river and the lake, adding an aerobic heterotrophic bacteria flora enrichment culture medium for enrichment culture,

an aerobic heterotrophic bacteria flora enrichment medium: 10kg of water were added:

aerating until dissolved oxygen is kept above 4mg/l, culturing for about 15 days, adjusting pH to 7-7.3, adding 0.5mg/l flocculation agent, precipitating, and collecting precipitate.

And putting all the sediments into an aerobic heterotrophic bacteria flora enrichment culture medium, carrying out secondary culture, and obtaining an aerobic heterotrophic bacteria flora stock without concentration.

(2) Expanding culture

Adding 20% of the aerobic heterotrophic bacteria flora stock into a corresponding enlarged culture medium, adding a corresponding concentrated culture medium, and culturing functional indigenous microbial flora on a large scale to finally form a functional indigenous microbial flora product

An aerobic heterotrophic bacteria flora expanding culture medium: 20kg of water were added: aerating until dissolved oxygen is kept above 4mg/l, adjusting pH to 7-7.3, and culturing for 3-10 d.

Aerating until dissolved oxygen is kept above 4mg/l, adjusting pH to 7-7.3, and culturing for 15d to obtain aerobic heterotrophic bacteria flora product.

(3) River Water treatment test

Taking 20kg of river water to be treated, adding a certain amount of glucose to ensure that the COD concentration of the river water reaches 100mg/l, and adjusting the river water to be treated to be test river water; adding 100mg/l aerobic heterotrophic bacteria flora product, aerating to make the dissolved oxygen of the river reach 4mg/l, taking test river water without adding aerobic heterotrophic bacteria flora product as a control, and sampling every 12h to test ammonia nitrogen.

TABLE 3 river Water treatment test results

	0	12	24	36	48
						Indigenous microorganisms	100	58.3	41.7	27.3	21.7
Control	100	79.5	68.3	59.3	48.5

As can be seen from the table 3, the COD of the river water can be obviously reduced by adding the indigenous aerobic heterotrophic bacteria flora product, the COD of the river water in 36 hours is reduced from 100mg/l to 27.3mg/l, the standard of the surface 4 is reached, and the COD of the river water in 48 hours is reduced to be less than 21.7 mg/l. The river water without the indigenous microorganisms is aerated, and the COD concentration is reduced, but the reduction range is far smaller than that of an experimental group, so that the aerobic heterotrophic bacteria flora product produced by the method can obviously reduce the COD of the river water body and improve the river water quality.

The embodiments described above are described to facilitate an understanding and appreciation of the invention by those skilled in the art. It will be readily apparent to those skilled in the art that various modifications to these embodiments may be made, and the generic principles described herein may be applied to other embodiments without the use of the inventive faculty. Therefore, the present invention is not limited to the above embodiments, and those skilled in the art should make modifications and alterations without departing from the scope of the present invention.

Claims

1. An indigenous microorganism directional amplification method for river and lake bioremediation is characterized by comprising the following steps:

(4) and (3) amplification culture: and (4) adding the second original strain of the indigenous microorganisms obtained in the step (3) into an expanded culture medium, and culturing by using a culture tank to finally form a functional indigenous microbial flora product.

2. The method according to claim 1, wherein the indigenous microorganisms used for the bioremediation of rivers and lakes comprise nitrifying bacteria flora, denitrifying bacteria flora and aerobic heterotrophic bacteria flora.

3. The method for directionally amplifying the indigenous microorganisms used for the bioremediation of rivers and lakes according to claim 1, wherein in the step (1), bottom sludge 20-40mm below the interface of sludge and water is collected, and the particles of the bottom sludge are less than 25 μm.

4. The method for directionally amplifying the indigenous microorganisms used for the bioremediation of rivers and lakes according to claim 1, wherein in the step (2), the enrichment culture medium of nitrobacteria flora comprises the following components, proportions and culture modes:

the culture mode is as follows: aerating until dissolved oxygen is kept above 4mg/l, and adding calcium carbonate to keep pH at 7-8; culturing for 3-7 days;

the denitrifying bacteria flora enrichment medium comprises the following components in percentage by weight and culture mode:

The aerobic heterotrophic bacteria flora enrichment medium comprises the following components in percentage by weight and culture mode:

5. The method for directionally amplifying the indigenous microorganisms used for the bioremediation of rivers and lakes according to claim 1, wherein the screening in step (2) is a screening of high-efficiency microbial flora, that is,

6. The method according to claim 1, wherein in the step (2), after the nitrifying bacteria flora in the bottom mud is cultured for one time in the enrichment medium, flocculation, precipitation and concentration are further performed, that is, a PAM flocculant is added to precipitate and concentrate the nitrifying bacteria flora to obtain a concentrated solution; and using the concentrated solution as a first stock of nitrobacteria flora;

in the step (3), after the first stock species of the nitrifying bacteria flora is subjected to secondary culture by an enrichment medium, performing flocculation, precipitation and concentration, namely adding a PAM flocculating agent to precipitate and concentrate the nitrifying bacteria flora to obtain a concentrated solution; and using the concentrated solution as a second stock of nitrifying bacteria flora.

7. The method for directionally amplifying the indigenous microorganisms used for the bioremediation of rivers and lakes according to claim 1, wherein in the step (4), the components, the mixture ratio and the culture mode of the nitrobacteria flora expanding culture medium are as follows:

8. The method for directionally amplifying the indigenous microorganisms used for the bioremediation of rivers and lakes according to claim 1, wherein in the step (4), the components, the mixture ratio and the culture mode of the denitrifying bacteria flora expanding culture medium are as follows:

the culture mode is as follows: culturing under stirring for 10-20 days.

9. The method for directionally amplifying the indigenous microorganisms used for the bioremediation of rivers and lakes according to claim 1, wherein in the step (4), the components, the mixture ratio and the culture mode of the aerobic heterotrophic bacteria flora expanding culture medium are as follows:

10. The application of the indigenous microbial community product for bioremediation of rivers and lakes is characterized in that the indigenous microbial community product is used for restoring the water quality of a river water body or riverway sediment.