A small part of the activated sludge is pumped back into the aeration tank to serve as the inoculum. The remaining major part of the sludge is pumped into large tanks called anaerobic sludge digesters where other kinds of bacteria grow anaerobically which digest the bacteria and the fungi in the sludge.
What type of inoculum is used in AD process?
Nov 19, 2021 · In its most general sense, an inoculum is a material used to inoculate some other material or substance, such as soil or compost. Inoculums are essentially live microorganisms, usually fungi. Some types can be added as amendments to benefit/improve soil or compost conditions, while others are harmful to plants.
Which type of sewage treatment is not possible in activated sludge?
It is sludge formed during primary sewage treatment. It is sludge formed during secondary sewage treatment. (ii) It possesses flocs of decomposer microbes. It does not possess flocs of decomposer microbes. (iii) It does not require aeration. …
How effective is inoculum for degrading dairy wastewater with high fat content?
In the first phase (P1), inhibition of methanogens in the sludge was evaluated using acetylene (1% v/v of headspace) and heat treatment (120 °C, 1 atm for 30 min). In the second phase (P2), three inoculum types obtained from common anaerobic sludges (bovine rumen and sludges from municipal and textile industrial wastewater treatment plants ...
How does sewage get treated?
Performance of a commercial inoculum for the aerobic biodegradation of a high fat content dairy wastewater. The effectiveness of a commercial inoculum for degrading a dairy wastewater with high fat content was evaluated, and compared with an activated sludge inoculum from a dairy wastewater treatment pond. Both inocula reached similar chemical oxygen demand removal in …
What is the use of inoculum?
Inoculum is a biological material used for inoculation, the process of introducing biological material, such as cells added to start a microbial culture. It may also refer to a biological material (like a virus or toxin or immune serum) that is injected to induce or increase immunity to a particular disease.Feb 16, 2022
What inoculum means?
In biology, inoculum refers to the source material used for inoculation. Inoculum may refer to: In medicine, material that is the source of the inoculation in a vaccine. In microbiology, propagules: cells, tissue, or viruses that are used to inoculate a new culture.
What is a bacterial inoculum?
The inoculum is any part of the pathogen that can initiate infection. Thus, in fungi the inoculum may be spores (Figs. 2-3A–2-3C), sclerotia (i.e., a compact mass of mycelium), or fragments of mycelium. In bacteria, mollicutes, protozoa, viruses, and viroids, the inoculum is always whole individuals of bacteria (Fig.
What is example of inoculum?
The definition of an inoculum is a substance introduced into the body to create or increase the body's resistance or immunity to a disease. A flu vaccine is an example of an inoculum.
How do you make an inoculum?
6.1. Inocula are prepared by growing C. neoformans in liquid YPAD overnight at 30 °C. Cells are counted by hemocytometer and, for an intranasal infection, 1×107 cells are washed twice with PBS and resuspended in 1 ml of PBS. Fifty microliters of this inoculum are used per mouse (5×105 cells).
What does the size of inoculum mean?
inoculum size is the required concentration of expected microorganism for a standard test. it is a believe to expect the standard suspension prepare is the inoculum size for a particular yield at different dilution rate for either pilot or industrial scale analysis.
What is inoculum consists of which material?
Inoculum preparation involves obtaining the organisms in an optimal state that is compatible with inoculation into cell culture, tissue culture, media, and fermentors. The prime objective is usually to achieve a high level of viable biomass in a suitable physiological state for use as an inoculum.
Why is inoculum not needed?
If the slurry of cow dung and water is fed into the biogas plant there is no need to provide inoculum for biogas production because the cow dung or excreta of cattle in itself contain a large number of anaerobic methanogenic bacteria. Therefore the slurry (cow dung and water) can be used for generation of biogas.Oct 13, 2018
What is the inoculum of a pathogen?
In other words, it is the portion of the individual pathogen that actually contacts the host.
How does an inoculum spread?
Inoculum can be spread by the wind, insects, rain, or by human disturbances. The inoculum must come into direct contact with the plant’s tissue to cause infection. An inoculum is considered any part of the pathogen fungus, such as the spore or mycelium.
What is the life cycle of a pathogen?
The pathogen’s life cycle runs from the time of primary inoculum to secondary inoculum, and on to secondary infection. Without the optimal conditions, the inoculum life cycle will fail and the crop will not become completely infected.
Is a secondary inoculum a primary inoculum?
However, if the inoculum already exists in the field and is infecting the crop, then it is considered a secondary inoculum. The secondary inoculum develops symptoms from the primary inoculum . Once symptoms develop from the secondary inoculum, the process is referred to as a secondary infection. This is the life cycle of the inoculum.
What is the effluent from a primary settling tank?
The effluent from the primary settling tank is taken for secondary treatment. The primary effluent is passed into large aeration tanks where it is constantly agitated which allows vigorous growth of useful aerobic microbes into flocs.
What is the BOD test?
The BOD test measures the rate of uptake of oxygen by micro-organisms, the greater the BOD of waste water, more is its polluting potential. The effluent is then passed into a settling tank where the bacterial ‘flocs’ are allowed to sediment and the sediment is called activated sludge .
What is the name of the tank where bacteria digest sludge?
The remaining major part of the sludge is pumped into large tanks called anaerobic sludge digesters where other kinds of bacteria grow anaerobically which digest the bacteria and the fungi in the sludge.
What is a floc?
Flocs are the masses of bacteria associated with fungal filaments to form mesh like structures. While growing, the microbes significantly reduces the BOD (biochemical oxygen demand) which is the amount of oxygen required to oxidize total organic matter in the effluent.
What is the gas produced by bacteria during digestion?
During digestion, bacteria produce a mixture of gases such as methane, hydrogen sulphide and carbon dioxide which form biogas . The effluent from the secondary treatment plant is generally released into natural water bodies like rivers and streams. Fig. sewage plant.
What is municipal waste water?
Municipal waste-water which contains large amounts of organic matter is called sewage. Before disposal, hence, sewage is treated in sewage treatment plants (STPs) by the heterotrophic microbes to make it less polluting. Sewage treatment is carried out in two stages. Primary treatment –. These treatment steps basically involve physical removal ...
How is floating debris removed?
These treatment steps basically involve physical removal of large and small particles. Initially, floating debris is removed by sequential filtration and then the grit are removed by sedimentation. All solids that settle form the primary sludge, and the supernatant forms the effluent.
What is the difference between sediment and supernatant?
The sediment is called primary sludge while the supernatant is called effluent. The primary sludge traps a lot of microbes and debris. It is subjected to composting, land fill or anaerobic digestion to produce biogas and manure. ADVERTISEMENTS:
What are the bacteria that grow in the aeration tank?
A large number of aerobic heterotrophic microbes grow in the aeration tank. They include bacteria of different types, some filamentous fungi, yeasts and protozoan. They form floes.
What are the two types of microbes that digest organic matter?
Anaerobic microbes digest the organic mass as well as aerobic microbes (bacteria and fungi) of the sludge. They are of two types, non-methanogenic and methanogenic. Methanogenic bacteria produce marsh gas which is a mixture of gases containing methane, H 2 S and C0 2.
What happens to the BOD of sewage?
As the BOD of the waste matter is reduced to 10-15% of raw sewage, it is passed into settling tank. In settling tank, the bacterial floes are allowed to undergo sedimentation. The effluent or supernatant is generally passed into natural waters like rivers and streams.
What is the sediment in a settling tank called?
The sediment of settling tank is called activated sludge. A part of it is used as inoculum in aeration tanks. The remaining is passed into a large tank called anaerobic sludge digesters. They are designed for continuous operation. The aerobic microbes present in the sludge get killed.
What is floes in biology?
Floes are masses of bacteria held together by slime and fungal filaments to form mesh like structures. The microbes digest a lot of organic matter, converting it into microbial biomass and releasing a lot of minerals. This reduces Biochemical Demand or BOD.
What are the stages of decomposition?
There are three stages of this treatment; primary, secondary and tertiary. Primary treatment is physical, secondary biological and tertiary chemical. Waste water can be passed into rivers after secondary treatment.
Most recent answer
Also you can check on the book "Biogas Handbook" it may be useful for your purposes.
All Answers (5)
According to the study by Jo De Vrieze et al.
Similar questions and discussions
How do you prepare inoculum for the biogas digester in the absence of animal manure?
Where can sewage be treated?
Sewage can be treated close to where the sewage is created , which may be called a "decentralized" system or even an "on-site" system (in septic tanks, biofilters or aerobic treatment systems ). Alternatively, sewage can be collected and transported by a network of pipes and pump stations to a municipal treatment plant.
What is sewage system?
Sewerage (or sewage system) is the infrastructure that conveys sewage or surface runoff ( stormwater, meltwater, rainwater) using sewers. It encompasses components such as receiving drains, manholes, pumping stations, storm overflows, and screening chambers of the combined sewer or sanitary sewer. Sewerage ends at the entry to a sewage treatment plant or at the point of discharge into the environment. It is the system of pipes, chambers, manholes, etc. that conveys the sewage or storm water.
What is wastewater used for?
Physical, chemical, and biological processes are used to remove contaminants and produce treated wastewater (or treated effluent) that is safe enough for release into the environment.
What is municipal wastewater treatment?
Sewage treatment (or domestic wastewater treatment, municipal wastewater treatment) is a type of wastewater treatment which aims to remove contaminants from sewage.
How much energy is needed for sewage treatment?
For conventional sewage treatment plants, around 30 percent of the annual operating costs is usually required for energy. The energy requirements vary with type of treatment process as well as wastewater load. For example, constructed wetlands have a lower energy requirement than activated sludge plants, as less energy is required for the aeration step. Sewage treatment plants that produce biogas in their sewage sludge treatment process with anaerobic digestion can produce enough energy to meet most of the energy needs of the sewage treatment plant itself.
What is wastewater treatment plant?
The term "sewage treatment plant" (or "sewage treatment works" in some countries) is nowadays often replaced with the term wastewater treatment plant or wastewater treatment station . Strictly speaking, the latter is a broader term that can also refer to industrial wastewater.
How much of the world's wastewater is treated?
At the global level, an estimated 52% of municipal wastewater is treated. However, wastewater treatment rates are highly unequal for different countries around the world. For example, while high-income countries treat approximately 74% of their municipal wastewater, developing countries treat an average of just 4.2%.
