Jasmine Grover Content Strategy Manager
Content Strategy Manager
Microbes of different kinds play a vital role in the production of biogas. Biogas is gaining acceptance and importance in the market due to its numerous benefits. The production of biogas is very simple. With minimum instruments, one can produce an ample supply of biogas. Biogas is also naturally produced in landfills.
| Table of Content |
Keyterms: Microbes, Biogas, Landfill, Gas, Methane, Sources of energy, Sewage treatment, Cellulose
Read More: Renewable and Non renewable sources of energy
Biogas
[Click Here for Sample Questions]
Biogas is an ideal fuel source that is made up of a mixture of several gases, especially methane (CH4) and is produced due to the activity of microbes. Biogas is one of the most widely used renewable sources of energy.
Biogas plant
Also Read:
| Related Articles | ||
|---|---|---|
| Microbes in Human Welfare | Microbiology | Pathogens |
| Human Health and Diseases | Infectious Diseases | E.coli |
Composition Of Biogas
[Click Here for Sample Questions]
Different kinds of microbes play different roles in the production of biogas. Microbes produce specific gases or a mixture of specific gases which is known as biogas. A class of microbes called methanogens exists which is well known for producing methane. One such bacteria belonging to this class is Methanobacterium. These bacteria are commonly found in anaerobic sludge during sewage treatment.
Methanobacterium
Other classes of microbes produce different gases. For example,
- Anaerobic bacteria produce carbon dioxide (CO2) and Hydrogen gas (H2) along with methane.
- Bacteria responsible for the fermentation of dough, the production of beverages, and the making of cheese produce carbon dioxide in large amounts.
| Name Of The Gas | Average Composition Present In Biogas |
|---|---|
| Methane | 50% to 70% |
| Carbon dioxide | 30% to 40% |
| Hydrogen | 5% to 10% |
| Nitrogen | 1% to 2% |
| Water vapour | 0.3% |
| Hydrogen Sulphide | Trace amounts |
Microbes In Production Of Biogas
[Click Here for Sample Questions]
Microbes used in the production of biogas are also present in a part of cattles' stomachs called the rumen. Cattle eat a variety of food, and cellulose is a major component of their food. When this cellulose enters rumen, the microbes present there react with it. The microbes help in breaking down the cellulose thus contributing greatly to the nutrition of cattle.
Rumen of cow
Some of these microbes run along with the excretory material. That is why cattle dung is full of microbes that can assist in the production of biogas. Cattle dung can be used to create gobar gas.
Read also: Population
Biogas Plant
[Click Here for Sample Questions]
Biogas plants are commonly located in areas that produce a lot of cattle dung. Villages are an ideal location to set up a biogas plant due to the large availability of cattle dung. Biogas can be used for lighting the house and cooking purposes. A biogas plant requires very little maintenance and can easily be handled by anyone. Trained professionals are not required for the production of biogas.
Biogas plant located in a village in India
Components Of Biogas Plant
[Click Here for Sample Questions]
A biogas plant has four major components namely a source, a digestion tank, a recovery unit, and a heat exchanger.
Structure of a Biogas plant
The functions of each of the components are tabulated below.
| Components | Functions |
|---|---|
| Source | The source is where the cattle dung and its slurry are collected. It is usually a large tank made of concrete. This tank is 10 to 15 feet deep. |
| Digestion tank | The cattle dung and slurry are fed into the digestion tank. This digestion tank has anaerobic properties. A floating cover is placed upon this digestion tank. As the biogas is created this floating cover rises upwards. |
| Recovery unit | The recovery unit is used to isolate the produced biogas from cattle dung and slurry. A pipe is connected to this recovery unit which carries the biogas to neighbouring houses. The used slurry is separated out through another outlet. |
| Heat exchanger | The heat exchanger is used to maintain the temperature of the digestion tank. |
Factors Affecting Production Of Biogas
[Click Here for Sample Questions]
Everything is affected by external and internal factors. Biogas is no exemption to that. The factors affecting the production of biogas are,
- Temperature
- Loading rate
- Total solid content
- Toxicity
- Degree of mixing
- Retention time
- Carbon/nitrogen (C/N) ratio
The quantity of biogas produced in a plant depends on all these factors.
Also Read:
| Related Articles | ||
|---|---|---|
| Life Processes | Typhoid | Active and Passive Immunity |
| Gram-negative bacteria | Binary Fission | Plant Cell |
Biogas And Landfills
[Click Here for Sample Questions]
Landfills are large pits dug in the ground to collect waste. Organic waste in the landfills decomposes and produces methane and carbon dioxide. Landfills can be modified by introducing an array of pipes to collect the biogas produced inside. It is often the case that landfills explode due to the collection of methane inside them.
Landfills Exploding
With the introduction of pipes, methane and carbon dioxide produced in the landfills can be collected and used as biogas. This technique is gaining acceptance in the market since it prevents the explosion of landfills as well as prevents the emission of methane into the atmosphere.
Substrates In Biogas Production
[Click Here for Sample Questions]
Various substrates used in Biogas production are as follows.
| Waste | Substrates |
|---|---|
| Animal waste |
|
| Plants |
|
| Plant waste |
|
| Urban waste |
|
| Human waste |
|
| By-products |
|
Advantages of Biogas
[Click Here for Sample Questions]
- Biogas is inexpensive and it is a renewable energy source.
- Biogas is safe to use and eco-friendly.
- Biogas is easy to generate and easy to store.
Advantages of Biogas
- Biogas can be easily transported.
- The residue of biogas can be used as manure.
- Biogas improves the sanitation of the surrounding areas.
Things to Remember
- Biogas is an ideal fuel source that is made up of a mixture of several gases, especially methane (CH4) and is produced due to the activity of microbes.
- Biogas is composed of methane, carbon dioxide, hydrogen, nitrogen, water vapour, and hydrogen sulphide.
- Methanogens are the microbes used in the production of biogas.
- The biogas plant has a source, a digestion tank, a recovery unit, and a heat exchanger.
- Biogas has numerous advantages over other fuel sources.
Also Read:
Sample Questions
Ques. Arrange the following in the decreasing order (most important first) of their importance, for the welfare of human society. Give reasons for your answer. [2 marks]
Biogas, Citric acid, Penicillin and Curd
Ans. Biogas is a renewable source of energy. It is used for cooking purposes and lighting. It is an eco-friendly alternative to other fuel sources. Citric acid is used as a preservative for packed food items. Penicillin belongs to the antibiotics class of drugs. It has multiple uses ranging from treating cold, fever to syphilis. Curd is a milk product commonly used in households. It is used for eating, cleaning, cooking, etc. Thus, the order of importance is
Penicillin > Biogas > Curd > Citric acid
Ques. Explain the working of a biogas plant. [2 marks]
Ans. In a biogas plant, substrates are added to the source tank in the form of a slurry. This slurry is pushed into a digestion tank where microbes are present. These microbes react with the substrates and produce biogas. On production of biogas, it is taken out of the digestion tank through an outlet pipe. This outlet pipe is directly connected to neighbouring houses. The used-up slurry is removed from the digestion tank through another outlet. After the used up slurry is removed, the new substrate can be added to the digestion tank.
Ques. If you compare biogas with Liquified Petroleum Gas (LPG) then which one is better? [2 marks]
Ans. Biogas is always better than Liquified Petroleum Gas (LPG). Biogas is eco-friendly as compared to LPG. It is also lighter in weight hence disperses quickly in the atmosphere. It does not contain harmful gases so is a much safer alternative than LPG. Biogas is easy to produce, store and transport but LPG on the other hand needs extensive processes for production and sophisticated instruments for storage and transfer. All these factors make biogas better than LPG.
Also Read: How to get rid of waste
Ques. Give advantages of Biogas. [2 marks]
Ans. Advantages of biogas are:
- It is inexpensive
- It is safe to use
- It is a renewable energy source
- It is eco-friendly
- It is non-polluting
- It is easy to generate
- It is easy to store
- It is easy to transport
Ques. Explain how the same microbes that produce biogas help in the digestion of cattle. [3 marks]
Ans. Microbes in the production of biogas play an important role. These microbes that are helpful for the production of biogas are also present in the rumen of cattle. The rumen is a part of the stomach of cattle where microbes such as methanogens are present. These microbes are very well capable of reducing cellulose. The diet of cattle is rich in cellulose. When this cellulose enters the rumen, microbes present there break down the cellulose. The nutrition thus obtained is absorbed by the body and the remaining material is thrown out of the body by the process of excretion. Some of the microbes present in the rumen leave the body along with the excreta.
Ques. Define biogas. Give the composition of components present in Biogas. [3 marks]
Ans. Biogas is an ideal fuel source that is made up of a mixture of several gases, especially methane (CH4) and is produced due to the activity of microbes.
| Name Of The Gas | Average Composition Present In Biogas |
|---|---|
| Methane | 50% to 70% |
| Carbon dioxide | 30% to 40% |
| Hydrogen | 5% to 10% |
| Nitrogen | 1% to 2% |
| Water vapour | 0.3% |
| Hydrogen Sulphide | Trace amounts |
Ques. Explain the importance of a digestion tank in a biogas plant. [2 marks]
Ans. The digestion tank is the most important component of a biogas plant. The cattle dung and its slurry are fed into the digestion tank. This digestion tank has anaerobic properties. A floating cover is placed upon this digestion tank. As the biogas is created this floating cover rises upwards. Without a digestion tank, the production of biogas will be impossible. That is why the digestion tank plays such an important role in a biogas plant.
Ques. Which substrates can be used to generate biogas? [2 marks]
Ans. A number of substrates can be used in the production of biogas. Some of the animal-based substrates are waste from slaughterhouses, sheep, buffaloes, cows, etc. Some of the plant-based substrates are sticks of jute, fodder, branches, twigs, straws, etc. Some of the human-generated substrates are paper, tobacco waste, urban waste, bran, etc.
Ques. What are Methanogens? [2 marks]
Ans. Methanogens are commonly found in the anaerobic sludge during sewage treatment and are also present in the rumen (a part of the stomach) of cattle. In the rumen, methanogens help in the breakdown of cellulose and their excreta called gobar, is rich in these bacteria. Therefore, cow dung can also be used to produce biogas commonly called gobar gas.
Ques. Why is Rhizobium categorised as a symbiotic bacterium? How does it act as biofertilisers? [CBSE 2012] [2 marks]
Ans. The nodules on the roots of leguminous plants are formed by Rhizobium bacteria for their survival. These bacteria fix atmospheric nitrogen into an organic form, which is used by the plant as nutrients. Since Rhizobium forms symbiotic association with leguminous plants these are considered symbiotic bacteria. So, it is used as biofertilisers.
For Latest Updates on Upcoming Board Exams, Click Here: https://t.me/class_10_12_board_updates
Do Check Out:
Comments