CN111621441A

CN111621441A - Microbial composition, microbial agent and method for purifying black and odorous water body

Info

Publication number: CN111621441A
Application number: CN202010528814.8A
Authority: CN
Inventors: 庄毅璇; 谭自航; 梅立永; 李彬辉; 骆灵喜; 李建
Original assignee: Pku Hkust Shenzhen Hongkong Environmental Protection Engineering Co ltd
Current assignee: Pku Hkust Shenzhen Hongkong Environmental Protection Engineering Co ltd
Priority date: 2020-06-11
Filing date: 2020-06-11
Publication date: 2020-09-04

Abstract

The invention relates to a microbial composition, a microbial agent and a method for purifying black and odorous water. The microorganism composition comprises six microorganisms of which the serial numbers are QN-1, QN-2, QN-3, QN-6, QN-11 and QN-22, wherein the six microorganisms are obtained by selectively culturing black and odorous bottom sludge in rivers in south lakeside of the Shandong Shi Zhen of Dongguan city through a bottom sludge inorganic salt culture medium. The microbial composition can realize the synchronous nitrification and denitrification of the sediment-overlying water environment, quickly reduce the N content, eliminate the odor of the water body and purify the black and odorous water body.

Description

Microbial composition, microbial agent and method for purifying black and odorous water body

Technical Field

The invention relates to the technical field of biology, in particular to a microbial composition, a microbial agent and a method for purifying black and odorous water.

Background

The black and odorous water body has become a water environment problem which directly influences urban image and production and life due to extremely poor sensory experience. The types and sources of pollutants in the black and odorous water body are in a complicated trend, and various exogenous sewage enters the riverway and then physically and chemically reacts with the river bottom mud sofa in the growing period. In the bottom mud pollutants of polluted river channels, ammonia nitrogen and sulfide account for main components, and the water depth influences atmospheric reoxygenation, so that the bottom mud is gradually converted into an anaerobic state, and H is easily generated when organic substances in the anaerobic environment are decomposed₂S、NH₃And malodorous gases such as mercaptans and black substances such as suspended sulfide particles including FeS and MnS, thereby causing "black odor".

At present, the treatment of black and odorous water bodies can be mainly divided into three types, namely physical methods, chemical methods and biological methods. The physical method mainly comprises the steps of aerating the river channel and dredging bottom mud; the chemical method mainly comprises the steps of carrying out enhanced flocculation, chemical oxidation and chemical precipitation on organic pollutants in the black and odorous water body by using chemical reagents such as a coagulant, a precipitator and the like; the biological method is mainly to culture plants or microorganisms in the black and odorous water body to transfer, convert and degrade organic pollutants in the black and odorous water body, thereby improving the water quality of the black and odorous water body. Compared with physical and chemical methods, the biological method is not easy to destroy the ecological environment, however, the traditional biological method has not good treatment effect.

Disclosure of Invention

Based on the above, there is a need for a microbial composition capable of improving the treatment effect of black and odorous water.

A microbial composition comprises six microorganisms with the numbers of QN-1, QN-2, QN-3, QN-6, QN-11 and QN-22, wherein the six microorganisms are obtained by selectively culturing black and odorous bottom sludge in rivers in south China of the lakeside of enterprise Stone town of Dongguan city through a bottom sludge inorganic salt culture medium.

Six microorganisms in the microorganism composition are screened out from the bottom mud of the polluted river, so that the synchronous nitrification and denitrification of the bottom mud-overlying water environment can be realized, the N content is rapidly reduced, the ammonia odor of the water body is eliminated, and the organic N in the bottom mud is generated by the anaerobic nitrification and denitrification of the six microorganisms₂And the risk that the bottom mud releases N to the overlying water body is greatly reduced, and the thickness of the bottom mud can be obviously reduced, so that the upper layer of the bottom mud is in a desertification state. In addition, the six microorganisms and other microorganisms in the water body are bred in a symbiotic manner, and the visibility of the overlying water is improved and the odor is eliminated by utilizing the self-purification effect of the environment.

In one embodiment, every 1L of the sediment mineral salts medium comprises: 0.8 g-1 g KNO₃、0.3g～0.5g(NH₄)₂SO₄、0.6g～1gKH₂PO₄、9g～12gNa₂HPO₄·12H₂O、0.06g～0.1gFeCl₃·6H₂O、0.2g～0.4gCaCl₂·7H₂O、0g～4gMgSO₄·7H₂O, 6.7g of sodium citrate, 3g of glass beads and 1mL of trace element liquid, wherein each 1L of the trace element liquid comprises: the volume ratio of HCl to water is 1: 4 hydrochloric acid solution 10mL, 0.19gCoCl₂·6H₂O、0.07gZnCl₂、0.006gH₃BO₃、0.036gNa₂MoO₄·2H₂O、0.024gNiCl₂·6H₂O and 0.002g CuCl₂·2H₂O; the pH value of the substrate sludge inorganic salt culture medium is 6.8-7.2.

In one embodiment, the step of selectively culturing black smelly bottom mud in rivers in south of lakeside of enterprise stone town of Dongguan city in a bottom mud inorganic salt culture medium to obtain six microorganisms comprises the following steps:

mixing black and odorous bottom sludge in the river of the south lakeside of the enterprise stone town of Dongguan city with the bottom sludge inorganic salt culture medium, and culturing to prepare bottom sludge bacterial liquid;

inoculating the bottom sludge bacterial liquid to a bottom sludge inorganic salt solid culture medium for culture, selecting bacterial colonies, inoculating the bacterial colonies to a robust culture medium for culture, and preparing bacterial colonies with consistent apparent characteristics, wherein the bottom sludge inorganic salt solid culture medium consists of the bottom sludge inorganic salt culture medium and agar, and the concentration of the agar in the bottom sludge inorganic salt solid culture medium is 15-25 g/L; and

and inoculating the bacterial colonies with consistent apparent characteristics into a substrate sludge culture medium for rescreening to obtain six microorganisms, wherein each 1L of the substrate sludge culture medium is formed by sterilizing 24-40 g of black and odorous substrate sludge in rivers in the south of the lakeside of enterprises, town of Dongguan city and water.

In one embodiment, every 1L of the enriched medium comprises: 3 to 5g of beef extract powder, 0.5 to 0.8g of tryptone, 0.4 to 0.6g of yeast powder and 3 to 5g of NaCl.

In one embodiment, the culture conditions for preparing the bottom sediment bacterial liquid are as follows: shaking culture is carried out for 2d to 3d under the condition of 22 ℃ to 27 ℃.

In one embodiment, the ratio of the mass of the black smelly bottom mud in the river in south of the lakeside of enterprise stone town of Dongguan city to the volume of the inorganic salt culture medium of the bottom mud is 8 g-10 g: 120 mL.

In one embodiment, in the step of inoculating the picked colonies on a robust medium for culturing, and preparing colonies with consistent colony appearance characteristics, the inoculation method is a plate marking method, a dilution plate method or a coating method.

In one embodiment, the mass ratio of the six microorganisms numbered QN-1, QN-2, QN-3, QN-6, QN-11 and QN-22 is 1: (0.5-2.5): (1-5): (0.5-3): (0.5-1): 1.

a microbial agent comprises the microbial composition and auxiliary materials.

A method for purifying a black and odorous water body, comprising the steps of:

adding the microbial composition into black and odorous water, wherein the adding amount of the microbes in the microbial composition is not less than 21 × 10 per square meter¹⁰cfu。

Drawings

FIG. 1 shows various bacterial agents of example 3NH of (2)₃-N concentration versus time;

FIG. 2 is a graph showing TN concentration and time dependence of various microbial inoculants in example 3;

FIG. 3 shows NH in the rapid infiltration process of example 4₃Concentration of-N, NH₃-N removal rate versus time.

Detailed Description

The present invention will now be described more fully hereinafter for purposes of facilitating an understanding thereof, and may be embodied in many different forms and are not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

In the biological denitrification process of urban sewage, three different biological reactions of aerobic oxidation, nitrification and denitrification of organic matters generally occur. According to the traditional denitrification theory, nitrification and denitrification reactions cannot occur simultaneously, the nitrification reaction is carried out under aerobic conditions, and the denitrification reaction is completed under anoxic conditions. However, recent studies at home and abroad show that nitrification and denitrification can be performed in the same reactor, i.e. Simultaneous Nitrification and Denitrification (SND).

The invention provides a microbial agent, which comprises a microbial composition and an auxiliary material. The microbial agent can be applied to purifying water bodies, particularly black and odorous water bodies. When the microbial agent is used for purifying a water body, the synchronous nitrification and denitrification of the sediment-overlying water environment can be realized, the N content is rapidly reduced, the ammonia smell of the water body is eliminated, the upper layer of the sediment is in a desertification state, the visibility of the overlying water is improved, and the odor is eliminated.

Specifically, the microbial composition comprises six microorganisms with the serial numbers of QN-1, QN-2, QN-3, QN-6, QN-11 and QN-22, wherein the six microorganisms are obtained by selectively culturing black and odorous bottom sludge in rivers in south lakeside of the Shandong Shi town of Dongguan city through a bottom sludge inorganic salt culture medium.

The microorganism with the number QN-1 is gram-negative bacteria and is in a cluster rod shape; the microorganism with the number QN-2 is a gram-negative bacterium and is in a spiral shape; the microorganism with the number QN-3 is a gram-positive bacterium and is in a straight rod shape; the microorganism with the number QN-6 is gram-positive bacteria and takes the shape of a round bar; the microorganism with the number QN-11 is gram-negative bacteria and takes the shape of a heap; the microorganism designated as QN-22 is a gram-positive bacterium and is bifurcated.

Specifically, the method comprises the steps of a-c, wherein the method comprises the following steps of selectively culturing black smelly bottom mud in rivers in south lakeside of enterprise Shizhen of Dongguan city by a bottom mud inorganic salt culture medium:

step a: mixing black and odorous bottom sludge in a river in south lakeside of enterprise stone town of Dongguan city with a bottom sludge inorganic salt culture medium, and culturing to prepare a bottom sludge bacterial liquid.

The microorganisms in the bottom sludge are rich in variety, the black and odorous bottom sludge in the river in south of the lakeside of the enterprise stone town of Dongguan is mixed with the inorganic salt culture medium of the bottom sludge and cultured, the denitrification microorganisms in the black and odorous bottom sludge can be proliferated according to rich N sources and trace elements in the culture medium, other microorganisms which do not use the N source as energy are selectively eliminated, and then various microorganisms capable of carrying out synchronous nitrification and denitrification in the black and odorous water body are preliminarily screened.

Specifically, the ratio of the mass of the black smelly bottom mud in the river in the south of the lakeside of the enterprise stone town of Dongguan city to the volume of the inorganic salt culture medium of the bottom mud is 8 g-10 g: 120 mL. In an alternative embodiment, the ratio of the mass of the black smelly bottom mud in the river in south of the lakeside of enterprise stone town of Dongguan city to the volume of the inorganic salt culture medium of the bottom mud is 8 g: 120mL, 8.5 g: 120mL, 9 g: 120mL or 10 g: 120 mL.

In this embodiment, the black and odorous bottom sludge in the river in south lakeside of enterprise stone town of Dongguan city is collected by multipoint sampling. In an alternative specific example, black smelly substrate sludge with a space of 2m in the middle of the river in south of the lakeside of enterprise Shizhen of Dongguan city is selected.

In the present embodiment, per 1LThe substrate sludge inorganic salt culture medium comprises: 0.8g to 1g KNO₃、0.3g～0.5g(NH₄)₂SO₄、0.6g～1g KH₂PO₄、9g～12g Na₂HPO₄·12H₂O、0.06g～0.1g FeCl₃·6H₂O、0.2g～0.4g CaCl₂·7H₂O、1.0g～1.4g MgSO₄·7H₂O, 6.7g of sodium citrate, 3g of glass beads and 1mL of trace element liquid. Wherein each 1L of the trace element liquid comprises: the volume ratio of HCl to water is 1: 4 hydrochloric acid solution 10mL, 0.19g CoCl₂·6H₂O、0.07g ZnCl₂、0.006g H₃BO₃、0.036g Na₂MoO₄·2H₂O、0.024g NiCl₂·6H₂O and 0.002g CuCl₂·2H₂And O, the pH value of the substrate sludge inorganic salt culture medium is 6.8-7.2. KNO₃And (NH4)₂SO₄The method is a necessary N source for nitrifying-facultative denitrifying bacteria and heterotrophic nitrifying-aerobic denitrifying bacteria in the bottom sludge, and the denitrification activity of the heterotrophic nitrifying-aerobic denitrifying bacteria can be greatly improved by adding sodium citrate serving as a carbon source in an auxiliary manner, so that the richness is increased. In order to facilitate the rapid proliferation of the denitrifier, trace elements for promoting the proliferation are added.

In an alternative embodiment, the mineral salts are present in an amount of 0.8g to 1g KNO per 1L of sediment₃、0.3g～0.5g(NH₄)₂SO₄、0.6g～1g KH₂PO₄、9g～12g Na₂HPO₄·12H₂O、0.06g～0.1g FeCl₃·6H₂O、0.2g～0.4g CaCl₂·7H₂O、1.0g～1.4g MgSO₄·7H₂O, 6.7g of sodium citrate, 3g of glass beads, 1mL of trace element liquid and water, wherein the volume ratio of HCl to water in each 1L of trace element liquid is 1: 4 hydrochloric acid solution 10mL, 0.19gCoCl₂·6H₂O、0.07g ZnCl₂、0.006g H₃BO₃、0.036g Na₂MoO₄·2H₂O、0.024g NiCl₂·6H₂O、0.002g CuCl₂·2H₂O and water, wherein the pH value of the substrate sludge inorganic salt culture medium is 6.8-7.2.

Further, every 1L of the sediment inorganic salt culture medium comprises: 0.8g to 0.9g KNO₃、0.35g～0.45g(NH₄)₂SO₄、0.8g～0.9g KH₂PO₄、11g～12g Na₂HPO₄·12H₂O、0.08g～0.1g FeCl₃·6H₂O、0.3g～0.4g CaCl₂·7H₂O、1.2g～1.4g MgSO₄·7H₂O, 6.7g of sodium citrate, 3g of glass beads and 1mL of trace element liquid. Wherein each 1L of the trace element liquid comprises: the volume ratio of HCl to water is 1: 4 hydrochloric acid solution 10mL, 0.19g CoCl₂·6H₂O、0.07g ZnCl₂、0.006g H₃BO₃、0.036g Na₂MoO₄·2H₂O、0.024g NiCl₂·6H₂O and 0.002g CuCl₂·2H₂O。

In an alternative embodiment, each 1L of the sediment mineral salts medium comprises: 0.82g KNO₃、0.4g(NH₄)₂SO₄、0.87g KH₂PO₄、10.5g Na₂HPO₄·12H₂O、0.1g FeCl₃·6H₂O、0.4g CaCl₂·7H₂O、1.27g MgSO₄·7H₂O, 6.7g of sodium citrate, 3g of glass beads and 1mL of trace element liquid. Wherein each 1L of the trace element liquid comprises: the volume ratio of HCl to water is 1: 4 hydrochloric acid solution 10mL, 0.19g CoCl₂·6H₂O、0.07g ZnCl₂、0.006gH₃BO₃、0.036g Na₂MoO₄·2H₂O、0.024g NiCl₂.6H₂O and 0.002g of CuCl₂.2H₂O; the pH value of the substrate sludge inorganic salt culture medium is 6.8-7.2.

In the embodiment, 0.5mL to 2mL of the acid-base indicator is further included in 1L of the sediment inorganic salt culture medium. In an alternative specific example, the acid-base indicator is bromothymol blue. Further, the acid-base indicator is 0.1% by mass of bromothymol blue ethanol solution. Of course, in other embodiments, the acid-base indicator is not limited to bromothymol blue, but may be other acid-base indicators. Of course, the substrate sludge inorganic salt medium is a medium sterilized at 121 ℃ for 20 min.

In this embodiment, the culture conditions for preparing the bottom sediment bacterial liquid are as follows: shaking culture is carried out for 2d to 3d under the condition of 22 ℃ to 27 ℃. In an alternative specific example, the culture conditions for preparing the bottom sediment bacterial liquid are as follows: shaking at 22 deg.C, 23 deg.C, 25 deg.C or 27 deg.C for 2d or 3 d. Further, the frequency of oscillation is 160 r/min.

In the embodiment, the method further comprises the step of taking a supernatant obtained by mixing and culturing the black and odorous bottom sludge in the river in south lakeside of enterprise stone town of Dongguan city with the bottom sludge inorganic salt culture medium, and inoculating the supernatant obtained by mixing and culturing the black and odorous bottom sludge in the river in south lakeside of enterprise stone town of Dongguan city with the bottom sludge inorganic salt culture medium to the bottom sludge inorganic salt culture medium for culturing, so as to screen out microorganisms which can take the black and odorous bottom sludge as a nitrogen source and an energy source. Of course, the step of inoculating the supernatant from the culture in the substrate inorganic salt medium to the culture in the substrate inorganic salt medium without any bacteria can be repeated. In an alternative embodiment, the number of repetitions is 2 to 5.

Step b: inoculating the bottom sediment bacterial liquid to a bottom sediment inorganic salt solid culture medium for culture, selecting a single colony, inoculating the single colony to a strong culture medium for culture, and preparing the colony with consistent colony apparent characteristics.

Specifically, the bottom sediment bacterial liquid is inoculated on a bottom sediment inorganic salt solid culture medium for culture by adopting a gradient dilution plate method. In an alternative embodiment, the dilution gradient of the bottom sediment liquid is 10²、10³、10⁵、10⁷. Of course, in other embodiments, the dilution gradient is not limited to the above, and may be adjusted as appropriate.

The culture conditions in the step of inoculating the bottom sediment bacterial liquid to the solid culture medium of the bottom sediment inorganic salt are as follows: culturing for 1-3 days at 27-30 ℃. In an alternative specific example, the conditions for culturing in the step of inoculating the bottom sediment bacterial liquid on the bottom sediment inorganic salt solid culture medium are as follows: culturing at 30 deg.c for 1-3 days.

Specifically, the substrate sludge inorganic salt solid culture medium consists of a substrate sludge inorganic salt culture medium and agar, and the concentration of the agar in the substrate sludge inorganic salt solid culture medium is 15 g/L-25 g/L. In an alternative specific example, the concentration of agar in the sediment inorganic salt solid medium is 18 g/L.

The strong culture medium can improve the thallus density and the microbial degradation activity, and ensure that the strong bacteria liquid has high-efficiency degradation capability when being inoculated to the culture medium containing the black and odorous substrate sludge. In this embodiment, each 1L of the robust medium comprises: 3 to 5g of beef extract powder, 0.5 to 0.8g of tryptone, 0.4 to 0.6g of yeast powder and 3 to 5g of NaCl. Further, each 1L of the robust medium comprises: 3.5 to 5g of beef extract powder, 0.5 to 0.8g of tryptone, 0.45 to 0.6g of yeast powder and 3.5 to 5g of NaCl. In an alternative specific example, each 1L of the enrichment medium consists of 3g to 5g of beef extract powder, 0.5g to 0.8g of tryptone, 0.4g to 0.6g of yeast powder, 3g to 5g of NaCl and water. Of course, both the substrate sludge inorganic salt solid culture medium and the rich culture medium are culture media which are sterilized at 121 ℃ for 20min and cooled.

Specifically, the culture conditions for culturing on the strong culture medium are as follows: shaking culture is carried out for 12 to 24 hours at the temperature of between 25 and 30 ℃. In an alternative embodiment, the conditions for culturing on the robust medium are: shaking and culturing at 30 deg.C for 12 h. Further, the rotation speed of the shaking culture was 160 r/min.

In this embodiment, the robust medium is an inclined tube medium, and the culture conditions for culturing on the robust medium are as follows: sealing the sand core rubber plug, and carrying out shaking culture at the rotating speed of 160r/min for 12-24 h at the temperature of 25-30 ℃.

Specifically, single colonies with good color, shape, growth vigor and separation degree on a substrate sludge inorganic salt solid culture medium are selected and inoculated on a strong culture medium for culture so as to prepare colonies with consistent colony appearance characteristics. In an alternative specific example, after culturing in the robust medium for 12-24 h, the method further comprises the step of picking a plurality of single colonies in the robust medium to respectively inoculate the single colonies in the robust medium which is not inoculated with any bacteria. This step can be repeated until the apparent characteristics of the colonies growing in the medium are completely consistent. In this embodiment, the step of picking up a plurality of single colonies in the robust medium to inoculate the single colonies in the robust medium without any bacteria is repeated 3 times, and of course, in other embodiments, the number of repetitions may be adjusted according to the apparent characteristics of the colonies.

Step c: and (4) inoculating the bacterial colonies with consistent apparent characteristics into a substrate culture medium for re-screening to obtain six microorganisms.

Specifically, every 1L of the substrate sludge culture medium is formed by sterilizing 24 g-40 g of black smelly substrate sludge in rivers in south lakeside of enterprise stone town of Dongguan city and water. The purpose of adopting the substrate sludge culture medium for re-screening is to screen out strains which can use black and odorous substrate sludge as a nitrogen source and energy and have good growth vigor. In an alternative embodiment, each 1L of the substrate sludge culture medium is formed by sterilizing 32g or 40g of black and odorous substrate sludge in rivers in south of the lakeside of the enterprise Shizhen of Dongguan city and water. Specifically, the substrate sludge culture medium is prepared by mixing black smelly substrate sludge in rivers in south of lakeside of enterprise and stone town of Dongguan city and water according to the proportion of 24 g-40 g of substrate sludge per 1L of substrate sludge culture medium, sterilizing at 100 ℃, and standing and cooling for later use.

In an alternative embodiment, the step of inoculating colonies with consistent colony appearance characteristics into the sludge medium and rescreening the colonies comprises: inoculating the bacterial colony with consistent apparent characteristics in a substrate sludge culture medium, placing the bacterial colony in a shaker at the temperature of 25-30 ℃ and the speed of 160r/min for 15-20 d, and then measuring NH in the overlying water body in the substrate sludge culture medium₃-N, TN (Total Nitrogen) and NO₃Concentration change of-NH-is screened out₃The inoculation amount of the bacterial colonies with consistent bacterial colony appearance characteristics when being inoculated in a substrate sludge culture medium is 3-6% (v/v), wherein the concentration of the bacterial colonies with consistent bacterial colony appearance characteristics is 1 × 10¹⁰cfu/L。

In an alternative embodiment, the mass ratio of six microorganisms numbered QN-1, QN-2, QN-3, QN-6, QN-11 and QN-22 is 1: (0.5-2.5): (1-1.5): (0.5-3): (0.5-1): 1. further, the mass ratio of six microorganisms numbered QN-1, QN-2, QN-3, QN-6, QN-11 and QN-22 was 1: 2.5: (1-1.5): 3: 1: 1. the nitrogen degrading efficiency of the microorganism combination is further improved by compounding the six microorganisms numbered as QN-1, QN-2, QN-3, QN-6, QN-11 and QN-22.

Six microorganisms in the microorganism composition are screened out from the polluted river sediment, so that the synchronous nitrification and denitrification of the sediment-overlying water environment can be realized, the N content is rapidly reduced, and the ammonia smell of the water body is eliminated; and the organic N in the bottom mud is generated into N by the anaerobic nitrification-denitrification of the six microorganisms₂And the risk that the bottom mud releases N to the overlying water body is greatly reduced, and the thickness of the bottom mud can be obviously reduced, so that the upper layer of the bottom mud is in a desertification state. In addition, the six microorganisms and other microorganisms in the water body are bred in a symbiotic manner, and the visibility of the overlying water is improved and the odor is eliminated by utilizing the self-purification effect of the environment.

Specifically, the auxiliary material is at least one selected from a dispersant, a carrier and a stabilizer. The dispersing agent is beneficial to uniform dispersion of six microorganisms in the microorganism composition during use; the carrier and stabilizer facilitate the storage and transport of the microorganisms in the microbial composition. It is understood that in other embodiments, the auxiliary material is not limited to the above, but may be other materials.

The invention also provides an application of the microbial composition in water purification.

Specifically, the microbial composition can be applied to purifying black and odorous water bodies and can also be applied to a rapid infiltration process to replace traditional activated sludge.

Tests show that the microorganism composition is adopted to treat closed black and odorous water, and NH is covered with water within 1-2 weeks₃The removal rate of N is more than 90%, the water body is clear and odorless, the visibility is high, and the phenomenon of black and odor is avoided. Under the same test condition, compared with 4 commercially available black and odorous riverway repairing bactericides (Henan Youjing black and odorous elimination bactericides, Bivofeng BZT bactericides, EPSB engineering bactericides and Shanghai Probo BE bactericides), the microbial composition has the advantages of quick response, strong decontamination, no rebound and the like.

Tests show that when the microbial composition is applied to a rapid infiltration process, the microbial composition replaces the traditional activated sludge to perform rapid start, and NH in rural domestic sewage is treated within 10-18 days₃the-N can be largely removed and stabilizedThe water reaches the first grade A standard.

The invention also provides a method for purifying black and odorous water, which comprises the step of adding the microbial composition into the black and odorous water, wherein the adding amount of the microorganisms in the microbial composition is not less than 1.21 × 10 per square meter¹⁰Further, the amount of the microorganism added in the microbial composition was 1.21 × 10 per square meter¹⁰cfu～1.35×10¹⁰cfu。

In an alternative embodiment, the microorganism composition is mixed with water to form a mixture, and the mixture is added to the black and odorous water body, wherein the concentration of the microorganisms in the mixture is not less than 0.67 × 10¹⁰cfu/L, and the adding amount of the mixture is 1.8L-2.0L.

DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION

The following detailed description is given with reference to specific examples. The following examples are not specifically described, and other components except inevitable impurities are not included. The examples, which are not specifically illustrated, employ drugs and equipment, all of which are conventional in the art. The experimental procedures, in which specific conditions are not indicated in the examples, were carried out according to conventional conditions, such as those described in the literature, in books, or as recommended by the manufacturer.

Example 1

(1) A plurality of black and odorous bottom mud with the depth of 1.2m is grabbed by a mud bucket at the four positions with the interval of 2m along the shore of the river in the south of the lakeside of the enterprise and the stone town of Dongguan city. Taking 10g of the 4 groups of sludge samples out respectively, placing the samples in 200mL triangular flasks containing 120mL bottom sludge inorganic salt culture medium and sterile glass beads (dispersed bottom sludge), plugging wood stoppers, performing shaking culture at the constant temperature of 160r/min and 25 ℃ for 2d, then taking 10% (V/V) supernatant liquid to inoculate a fresh bottom sludge inorganic salt culture medium (the fresh bottom sludge inorganic salt culture medium refers to a sterilized bottom sludge inorganic salt culture medium which is not inoculated with any bacteria), keeping the culture condition unchanged, and continuing to culture for 2 d. Then repeating the operation of taking 10% (V/V) supernatant bacterial liquid of the substrate sludge inorganic salt culture medium and re-inoculating the supernatant bacterial liquid to a fresh substrate sludge inorganic salt culture medium for 2d 3 times to obtain 4 groups of substrate sludge bacterial liquids containing bacteria which can take black and odorous substrate sludge as a nitrogen source and an energy source. Wherein:

every 1L of the substrate sludge inorganic salt culture medium consists of 0.82g KNO₃、0.4g(NH₄)₂SO₄、0.87g KH₂PO₄、10.5gNa₂HPO₄·12H₂O、0.1g FeCl₃·6H₂O、0.4g CaCl₂·7H₂O、1.27g MgSO₄·7H₂O, 6.7g of sodium citrate, 3g of glass beads and 1mL of trace element liquid. Wherein, every 1L of the microelement liquid is prepared by mixing HCl and water according to the volume ratio of 1: 4 hydrochloric acid solution 10mL, 0.19g CoCl₂·6H₂O、0.07g ZnCl₂、0.006g H₃BO₃、0.036g Na₂MoO₄·2H₂O、0.024gNiCl₂.6H₂O and 0.002g of CuCl₂.2H₂O and water, and the pH value of the substrate sludge inorganic salt culture medium is 6.9. The sediment inorganic salt culture medium is sterilized at 121 ℃ for 20min, and after sterilization, 1mL of bromothymol blue (BTB, 1% ethanol solution) is added and cooled for standby.

(2) Respectively taking 2mL of the supernatant of the 4 groups of bottom mud bacterium liquid obtained in the step (1), respectively placing the supernatant into sterilized centrifuge tubes, and then carrying out 10% treatment on the 4 groups of bottom mud bacterium liquid by using sterile normal saline²、10³、10⁵、10⁷Diluting, respectively sucking 200 mu L of bacterial liquid after each gradient dilution, coating the bacterial liquid on a substrate sludge inorganic salt solid culture medium, and culturing for 1-3 days in a 30 ℃ incubator until obvious bacterial colonies grow out. The substrate sludge inorganic salt solid culture medium consists of a substrate sludge inorganic salt culture medium and agar, and the concentration of the agar in the substrate sludge inorganic salt solid culture medium is 20 g/L.

(3) And (3) selecting a single colony with good color, shape, growth and separation degree by using an inoculating loop, inoculating the single colony into a 100mL inclined tube assembled with 80mL of a strong culture medium, sealing a sand core rubber plug, placing the sand core rubber plug at 30 ℃, performing shaking table culture at 160r/min for 12-24 h, and performing plate streaking separation when turbidity occurs. The steps are repeated for 2 times until the apparent characteristics of the colonies growing on the culture medium are completely consistent, and the single bacterial strain is obtained. Wherein each 1L of the culture medium comprises 3g of beef extract powder, 0.6g of tryptone, 0.4g of yeast powder, 3g of NaCl and deionized water, and is sterilized at 121 ℃ for 20 min.

After rejuvenation culture, 19 strains which can grow by using black and odorous substrate sludge as a nitrogen source and energy and have good growth vigor are obtained.

(4) Culturing the 19 strains obtained in the step (3) in a robust culture medium to a logarithmic growth phase, collecting bacterial liquid, performing high-speed centrifugation at 12000r/min for 8min, washing residues on the surface of bacterial mud precipitates by using sterile physiological saline, repeating the centrifugation for 1 time, discarding supernatant, re-dispersing the bacterial mud precipitates into the sterile physiological saline to prepare 19 groups of bacterial suspensions, wherein the concentration of bacteria in each group of bacterial suspensions is 1 × 10¹⁰cfu/L。

(5) Respectively inoculating the 19 groups of bacterial suspensions into a substrate sludge culture medium according to the volume ratio of 3% (v/v), and carrying out shake cultivation for 15d at 30 ℃ and 160r/min to degrade the overlying water body N. Wherein, every 1L of the substrate sludge culture medium is formed by sterilizing 4 sludge samples (10 g of each sludge sample) and deionized water which are uniformly mixed. Method for measuring NH in overlying water by adopting Hash spectrophotometry₃-N, TN and NO₃-rate of change of concentration, NH after 15d₃Screening with-N degradation rate of above 39% and TN degradation rate of above 18% as standard to obtain six strains, numbered as QN-1, QN-2, QN-3, QN-6, QN-11 and QN-22. NH in overlying water numbered QN-1, QN-2, QN-3, QN-6, QN-11 and QN-22₃The degradation rates of-N and TN are shown in Table 1.

TABLE 1

(6) The DNA of six bacteria, numbered QN-1, QN-2, QN-3, QN-6, QN-11 and QN-22, were extracted and sequenced from the respective genes, and then the 16S rDNA gene sequences of QN-1, QN-2, QN-3, QN-6, QN-11 and QN-22 were uploaded to the NCBI database for BLAST alignment, the results of which are shown in Table 2. Further, gram stain (G stain) and microscopic observation were carried out on six kinds of bacteria, numbered QN-1, QN-2, QN-3, QN-6, QN-11 and QN-22, and the results are shown in Table 2.

TABLE 2

As is clear from Table 1, the bacterium with the number QN-1 belongs to the genus Methylobacterium (Methylobacterium), the bacterium with the number QN-2 belongs to the genus Nitrospira (Nitrospira), the bacterium with the number QN-3 belongs to the genus Bacillus (Bacillus), the bacterium with the number QN-6 belongs to the genus Lactobacillus (Lactobacillus), the bacterium with the number QN-11 belongs to the genus Paracoccus (Paracoccus), and the bacterium with the number QN-1 belongs to the genus Bifidobacterium (Bifidobacterium).

Example 2

(1) The 6 strains of bacteria obtained in example 1 are compounded according to the following mass ratio to obtain six groups of microbial compositions:

a first group: QN-1: QN-2: QN-3: QN-6: QN-11: QN-22 ═ 1: 1: 1: 1: 1: 1;

second group: QN-1: QN-2: QN-3: QN-6: QN-11: QN-22 ═ 2: 1: 2: 2: 1: 2;

third group: QN-1: QN-2: QN-3: QN-6: QN-11: QN-22 ═ 1: 2: 1: 1: 2: 1;

and a fourth group: QN-1: QN-2: QN-3: QN-6: QN-11: QN-22 ═ 1: 2: 2: 2: 1: 1;

and a fifth group: QN-1: QN-2: QN-3: QN-6: QN-11: QN-22 ═ 1: 2.5: 1.5: 3: 1: 1.

(2) the six groups of microbial compositions obtained in step (1) were added to the substrate sludge medium in a ratio of 5% by volume of the microbial compositions to the substrate sludge medium (same formulation as in example 1), with the bacterial concentration in each group of microbial compositions being 1 × 10¹⁰cfu/L, then placing the mixture in a shaking table at 30 ℃ and 160r/min for 15 d; synchronously setting blank contrast, and measuring NH in overlying water by adopting Hash spectrophotometry₃-N, TN and NO₃ ^-Rate of change of concentration. The results are shown in Table 3.

TABLE 3

As can be seen from Table 3, QN-1: QN-2: QN-3: QN-6: QN-11: the mass ratio of QN-22 is 1: 2: 1: 1: 2: at 1 time, NH is degraded₃The effect of-N and TN is better.

Example 3

4 existing microbial agents for treating black and odorous water are purchased and compared with the third group of microbial compositions (QNF) in the embodiment 2 for comparison, wherein the microbial agent 1 is Henan Youjing Oaku-black and odorous eliminating microbial agent, the microbial agent 2 is Biwofeng BZT microbial agent, the microbial agent 3 is EPSB engineering microbial agent, and the microbial agent 4 is Shanghai Proro BE microbial agent. The specific operation is as follows:

adding a microbial inoculum 1, a microbial inoculum 2, a microbial inoculum 3, a microbial inoculum 4 and QNF into a substrate sludge culture medium according to the volume ratio of 5% of the microbial inoculum to the substrate sludge culture medium (with the same formula as in example 1), wherein the bacterial concentration in each microbial inoculum is 1 × 10¹⁰cfu/L, shake culturing at 30 deg.C and 160r/min, and measuring NH in overlying water by Hash spectrophotometry₃-N, TN and NO₃ ^-Rate of change of concentration. The results are shown in FIGS. 1 and 2.

As can be seen from FIGS. 1 and 2, NH was observed after 38 days for the QNF group₃The content of-N is lower than that of the other four microbial inoculums, and after 34 days, the content of TN is lower than that of the other four microbial inoculums, and the effect of degrading N is better than that of the other four microbial inoculums.

Example 4

(1) Numbering QN-1, QN-2, QN-3, QN-6, QN-11 and QN-22 according to a mass ratio of 1: 2: 1: 1: 2: 1 to form the microbial composition.

(2) And (2) inoculating the microbial composition in the step (1) into a rejuvenation culture medium (the formula is the same as that in the example 1), and enriching for 48 hours in aeration sunlight to activate strains to obtain a composite bacterial liquid.

(3) The rapid infiltration tank is fully filled with pretreated domestic sewage to submerge surface filler, the height of the rapid infiltration tank is 3cm, and then the surface filler is distributed according to the proportion of every 1m²Adding 0.08kg of composite bacterial liquid into the filler, pouring the composite bacterial liquid obtained in the step (2) into a rapid infiltration tank to be mixed with domestic sewage,closing the water outlet ball valve to hold water for 48h, and hanging the membrane.

(4) After 48h of biofilm formation, draining, then introducing domestic sewage to be treated, and adopting a Hash spectrophotometry method to detect NH rapidly permeating into and out of water every day₃-N, TN and NO₃The rate of change of the concentration, the results are shown in FIG. 3.

As can be seen from FIG. 3, the microbial composition obtained in step (1) was applied to a rapid infiltration process, and NH in water was continuously extracted by rapid infiltration on day 8₃N and TN meet the criteria of class A.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A microbial composition, which comprises six microorganisms numbered as QN-1, QN-2, QN-3, QN-6, QN-11 and QN-22, wherein the six microorganisms are obtained by selectively culturing black smelly bottom sludge in rivers in the south of the lakeside of enterprises, township of Dongguan city through a bottom sludge inorganic salt culture medium.

2. The microbial composition of claim 1, wherein each 1L of the sediment mineral salts medium comprises: 0.8g to 1g KNO₃、0.3g～0.5g(NH₄)₂SO₄、0.6g～1g KH₂PO₄、9g～12g Na₂HPO₄·12H₂O、0.06g～0.1g FeCl₃·6H₂O、0.2g～0.4g CaCl₂·7H₂O、1.0g～1.4g MgSO₄·7H₂O, 6.7g of sodium citrate, 3g of glass beads and 1mL of trace element liquid, wherein each 1L of the trace element liquid comprises: the volume ratio of HCl to water is 1: 4 hydrochloric acid solution 10mL, 0.19g CoCl₂·6H₂O、0.07g ZnCl₂、0.006g H₃BO₃、0.036g Na₂MoO₄·2H₂O、0.024g NiCl₂·6H₂O and 0.002g of CuCl₂·2H₂O; the pH value of the substrate sludge inorganic salt culture medium is 6.8-7.2.

3. The microbial composition of claim 1, wherein the step of selectively culturing black smelly substrate sludge from rivers in south lakeside of enterprise stone town of Dongguan city in substrate sludge inorganic salt medium to obtain six kinds of said microorganisms comprises:

4. The microbial composition of claim 3, wherein each 1L of said robust culture medium comprises: 3 to 5g of beef extract powder, 0.5 to 0.8g of tryptone, 0.4 to 0.6g of yeast powder and 3 to 5g of NaCl.

5. The microbial composition of claim 3, wherein the culture conditions for preparing the bottom sludge broth are as follows: shaking culture is carried out for 2d to 3d under the condition of 22 ℃ to 27 ℃.

6. The microbial composition according to claim 3, wherein the ratio of the mass of the black smelly bottom mud in the river in south lakeside of enterprise stone town of Dongguan city to the volume of the inorganic salt culture medium of the bottom mud is 8-10 g: 120 mL.

7. The microbial composition according to claim 3, wherein in the step of inoculating the picked colonies on a robust medium to culture the colonies with consistent apparent characteristics, the inoculation method is a plate-streaking method, a dilution plate method or a spreading method.

8. The microbial composition according to any one of claims 1 to 7, wherein the mass ratio of the six microorganisms numbered as QN-1, QN-2, QN-3, QN-6, QN-11 and QN-22 is 1: (0.5-2.5): (1-1.5): (0.5-3): (0.5-1): 1.

9. a microbial agent, comprising the microbial composition of any one of claims 1 to 8 and an adjuvant.

10. A method for purifying black and odorous water is characterized by comprising the following steps:

adding the microbial composition according to any one of claims 1 to 8 into black and odorous water, wherein the addition amount of the microorganisms in the microbial composition is not less than 1.21 × 10 per square meter¹⁰cfu。