The principle of microbial treatment of sewage is discussed, and the microbiological principles and

Biochemical treatment is a process that uses microorganisms to treat organic matter and pollutants in wastewater, so it is also called biological treatment of wastewater.

Microorganisms are a class of organisms with small size and simple structure, mainly including bacteria, actinomycetes, algae, fungi, rickettsia bacteria, mycoplasma, protozoa and metazoa, among which some species of bacteria, actinomycetes, protozoa and metazoa are closely related to wastewater treatment.

1. Bacteria: It is a single-celled organism, with three types: spherical, rod-shaped and spiral-shaped. The main role in the wastewater treatment process is the colloidal group composed of a variety of bacteria. In a suitable environment, bacteria can be cleft every 20 30min to generate 2 bacteria.

2. Filamentous bacteria: It is a general term for a large group of microorganisms that form filamentous microorganisms by connecting cells to form filaments, also known as filamentous microorganisms. These include microbiota such as filamentous bacteria, filamentous fungi, and filamentous algae.

Filamentous bacteria are the main skeleton materials of activated sludge flocs in the process of wastewater biochemical treatment. If the number of filamentous bacteria is insufficient, activated sludge flocs cannot be formed, and efficient slurry-water separation cannot be carried out. As a result, a clear supernatant cannot be obtained, making the effluent turbid.

But when there are too many filamentous bacteria, it can cause the activated sludge to swell.

3. Protozoa: In the wastewater activated sludge treatment method, there are three main types of protozoa: carpods, flagella and cilia. There are representative organisms such as amoeba, flagellates and ciliates.

The biological contact oxidation method is an intermediate method of activated sludge.

Biofilm between the biofilter and the biofilter.

The process is characterized by setting the filler in the pool and aerating the bottom of the pool.

The sewage is oxygenated, and the sewage in the pool is in a flowing state, so as to ensure that the sewage is in full contact with the filler in the sewage, and avoid the defect of uneven contact between the sewage and the filler in the biological contact oxidation tank.

In this method, the oxygen required by the microorganisms is supplied by blast aeration, and after the biofilm grows to a certain thickness, the microorganisms on the filling wall will carry out anaerobic metabolism due to lack of oxygen, and the resulting gas and the scouring effect formed by aeration will cause the biofilm to fall off and promote the growth of new biofilm, at this time, the shedding biofilm will flow out of the pool with the effluent.

The biological contact oxidation method, also known as the submerged biological filter, is provided with a packing in the reactor, and the oxygenated wastewater is connected with the filler covered with biofilm, and the wastewater is purified under the action of the biofilm. In the early stage of the biological contact oxidation method, a small amount of bacteria adheres to the surface of the filler, and a thin biofilm is gradually formed due to the reproduction of bacteria. in dissolved oxygen.

Under the condition that there is sufficient food, the microorganisms multiply very rapidly, and the biofilm gradually thickens. Dissolved oxygen and organic matter in sewage are used by microorganisms by diffusion. However, when the biofilm reaches a certain thickness, oxygen can no longer diffuse to the inner layer of the biofilm, aerobic bacteria die, and facultative bacteria and anaerobic bacteria die.

In the inner layer, the anaerobic layer is formed, and the dead aerobic bacteria are used as the substrate, and the anaerobic bacteria continue to develop on this basis. After a period of time, the number begins to decline, coupled with the escape of metabolic gas products, which causes a large amount of the inner biofilm to be shed. On the surface of the filler where the biofilm has been shed, a new biofilm develops again.

Inside the contact oxidation tank, due to the packing surface area.

larger, so each stage of biofilm development is present at the same time, so that the ability to remove organic matter is stabilized at a certain level. The biofilm has a three-dimensional structure in the cell, which is beneficial for maintaining stable treatment capacity.

Extraction code: w5d8 "It is an engineering technology that applies microbial wild mushrooms or engineering fungi to serve large-scale production in industry, agriculture, medicine, environmental protection, etc., it is directly based on the microbial industry, and is a discipline that has developed rapidly with the rapid development of the microbial industry. Due to the close integration of microbial industry and chemical engineering, microbial engineering has been continuously developed.

Microbial engineering has been involved in many fields, including: clean production of biochemical raw materials, food and beverages, pharmaceutical products, biofuels, microbial oil recovery, biomaterials, magnetic materials, etc.

There are four main types of organisms involved in wastewater treatment:

1.Bacteria: Bacteria are the smallest of the biota used in wastewater treatment, and they have the ability to decompose and absorb various organic matter under aerobic and anaerobic conditions.

There are bacteria that play a role in the biological treatment of sewage. Colloids. Jersey bacteria.

Nitrifying bacteria. Denitrification bacteria. There are several kinds of polyphosphate bacteria.

2.Protozoa: Protozoa have the ability to swallow organic matter in sewage, bacteria, rapidly oxidative and decompose in the body, so in the activated sludge method and biofilm.

In addition to removing organic matter and accelerating the decomposition rate of organic matter, it can also regenerate the surface adhesion ability of biofilms, and acoustic animals are single-celled aerobic organisms.

3.Algae: Algae are plants, containing chlorophyll, when chlorophyll absorbs carbon dioxide and water for photosynthesis to produce carbohydrates, it will release a large amount of oxygen into the water, and the stabilization pond is to use this oxygen to oxidize the organic matter of sewage.

4: Metazoans, the organisms introduced above are single-celled, and there are various organs in the body, and the metazoans involved in sewage treatment include various types of metazoans such as smaller rotifers to beetles, insects, and larvae that inhabit biological filters.

You can look at drainage engineering or environmental biology, the basic principle of sewage treatment is the growth curve of microorganisms.

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There are physical, chemical and biological methods for wastewater treatment, and the biological method of treating wastewater with microorganisms is widely used due to its high efficiency and low cost. The microorganisms that can remove poisons are mainly bacteria, molds, and yeasts.

and some protozoa.

They can turn organic matter in water into simple inorganic matter, and purify sewage through growth and reproduction activities. There is a kind of bacillus that can convert phenolic substances into acetic acid for absorption and utilization, and the phenol removal rate can reach 99%; A mercury-resistant bacterium can absorb mercury from wastewater into the bacteria through artificial culture, and after changing the conditions, the bacteria release the mercury into the air with activated carbon.

Not **. Some microorganisms can detoxify DDT by converting it into a substance that dissolves in water. Every year, 1.5 million tonnes of ** are transported into the world's waters, polluting the oceans, removing these oils, fungi are more capable than bacteria.

In detoxification and purification, different microorganisms have their own "tricks"! Subtilis.

Potato bacillus can remove hexanecoolamine; Pseudomonas sol can oxidize highly toxic cyanide.

Red yeast and psoriasis.

The bacteria have the ability to decompose polychlorinated biphenyls.

The biofilm method is commonly used to treat wastewater with microorganisms. All sewage treatment plants have fixed filter media such as gravel, cinder and plastic, etc., and the surface of the filter media is covered with a layer of viscous composed of various microorganisms, called biofilm. The biofilm is mainly composed of bacterial colloids and a large number of fungal hyphae, and many protozoa also inhabit the surface.

When the sewage passes through the surface of the filter material, the biofilm adsorbs a large amount of various organic matter in the water, and at the same time, the microbial community on the membrane uses dissolved oxygen to decompose the organic matter, producing soluble inorganic matter that flows away with the water and produces carbon dioxide.

and hydrogen, etc., are released into the atmosphere to purify the wastewater.

There is also an activated sludge method. The so-called activated sludge is a brown flocculent mud particle formed by the condensation of bacteria and protozoa that can form a colloidal group, and the organic and inorganic suspended solids adsorbed by them, which has a strong adsorption and oxidative decomposition ability to organic matter.

Although the use of microorganisms to purify sewage has made gratifying achievements, there is still a lot of work to be done in improving work efficiency, so it cannot be widely used to eliminate pollution.

Treatment of organic pollutants: the use of microorganisms, microorganisms need nutrients, it absorbs nutrients in organic matter, and then microorganisms multiply themselves. The use of microorganisms to treat sewage is to let microorganisms decompose organic matter as its food, and then after the microorganisms grow, they decompose the microorganisms and then treat the sludge, and the microorganisms are suspended.

CDC ammonia nitrogen and total nitrogen in sewage treatment and rapid degradation wastewater meet the discharge standard in a short time. Microbial strains are suitable for high ammonia nitrogen chemical wastewater, landfill leachate, petrochemical wastewater, municipal sewage and ecological restoration of black and odorous water bodies. The main role is to control ammonia nitrogen exceeding the standard, CDC exceeding the standard, and total nitrogen exceeding the standard; Mainly for large sewage treatment plants, garbage treatment plants; Landfill leachate treatment.

Answer]:Principle: Bioadsorption: Some non-degradable pollutants in wastewater, such as synthetic organic matter, metal salts and some radioactive substances, can be removed by the adsorption characteristics of microorganisms.

Biological oxidation: Some rapidly degradable pollutants in wastewater are oxidized and decomposed by microorganisms, and are eventually released in the form of carbon dioxide and other gases.

Biosynthesis: Microorganisms use the organic matter in wastewater to synthesize Danchangchong's own fine-mold cell annihilation composition, and achieve the purpose of evolving sewage by removing microorganisms.

Common methods: activated sludge method;

biofilm method; oxidation pond method;

Anaerobic treatment.

Microorganisms can be divided into aerobic and anaerobic two, their treatment methods are different, in the aerobic treatment process, people need to continuously inject oxygen into the sewage pool, sufficient oxygen to make the microorganisms in the orange lead sewage multiply. Microorganisms can be divided into aerobic and anaerobic two kinds of good natural plums, their treatment of sewage is different, in the aerobic treatment process, people need to continuously inject oxygen into the sewage pool, sufficient oxygen to make the microorganisms in the sewage multiply. Microorganisms will eat it.

After the various substances in the sewage are full, they sink to the bottom of the water and become sludge, and the cleaned water passes. The activated sludge becomes clear after sedimentation and separation.