Quick Answer: The Biogas Generation Working Model is a small digester tank with a feed opening, a gas pipe leading to a burner and a lower outlet tube with a clamp, set on a tray base. It shows how microbes break down organic waste without oxygen to produce biogas, a fuel made mostly of methane and carbon dioxide.
How the Model Digester Works
The listing image of the biogas generation working model shows a blue cylindrical tank labelled as a biogas plant, standing on a tray with a wooden frame. A red cap closes an opening on top of the tank, a clear tube runs from the top of the tank to a black burner base, and a second tube near the bottom of the tank is closed by a pinch clamp. In models of this design the top opening is used for charging the tank with feed, and the lower tube for drawing off spent slurry.
Inside a real digester, several groups of microbes work in sequence once air is excluded. Some break large molecules in the waste into sugars and fatty acids, others turn those into acetic acid, hydrogen and carbon dioxide, and methane-producing microbes finish the job. The gas that collects above the slurry is typically around half to two thirds methane, with most of the rest carbon dioxide. The process is slow and depends on warmth: gas production usually takes days to weeks to get going and is fastest at around 30 to 40 degrees Celsius.
The model mirrors the household biogas plants widely built in rural India, where cattle dung and water are fed into a sealed digester and the gas is piped to a kitchen burner. The leftover slurry, called digestate, keeps most of the nutrients of the original waste and is used as fertiliser. Tank capacity and the burner fitting should be confirmed at enquiry. For another renewable-energy model, see the Water Wheel Dynamo Model.
Specifications
| Model type | Small-scale anaerobic digester (biogas plant) model |
| Digester | Cylindrical tank with a capped opening on top, as pictured |
| Gas line | Tube from the top of the tank to a burner base |
| Lower outlet | Tube closed by a pinch clamp |
| Base | Tray with wooden frame |
| Tank capacity and burner fitting | Confirm at enquiry |
Safety & Handling
- Biogas is flammable: light it only in a brief, teacher-led demonstration at the burner, in a ventilated space, and never bring a flame near the tank or its openings.
- Wear gloves when handling dung or food-waste slurry, and wash hands thoroughly afterwards.
- Leave space above the slurry for gas to collect, and do not overfill the tank.
- Empty and rinse the tank outdoors at the end of a project; raw biogas and slurry smell because of traces of hydrogen sulfide.
Uses in Teaching
- Demonstrating anaerobic digestion of cattle dung or kitchen waste
- Teaching renewable energy and waste-to-energy in environmental science
- Running a project that compares gas output at different temperatures or feeds
- Displaying a working rural-energy model at science exhibitions
Why Choose LabEquip
Environmental science and biology teachers use this model to connect waste management with energy, and it is a common choice for school exhibitions on sustainable living. LabEquip supplies it through the STEM kits range, and our contact page can help with questions about setting it up.
Frequently Asked Questions
What is biogas made of?
Mainly methane, typically around half to two thirds of the gas, with most of the rest being carbon dioxide. Small amounts of hydrogen sulfide and water vapour are also present, which is why raw biogas can smell of rotten eggs.
What should be put in the digester?
A slurry of fresh cattle dung mixed with a similar amount of water is the traditional feed, and vegetable peelings and other soft kitchen waste can also be used. Oils, plastics, soap and disinfectants should be kept out because they harm the microbes.
How long does it take to produce gas?
Usually several days to a few weeks, depending mostly on temperature. The microbes are most active in warm conditions of around 30 to 40 degrees Celsius, so gas production slows noticeably in cold weather.
Why must air be kept out of the tank?
The methane-producing microbes are anaerobic, and oxygen stops them working. Sealing the tank also keeps the gas in and prevents air from mixing with methane inside the tank, where the mixture could burn.
Is it safe to burn the gas in class?
Only as a brief demonstration led by a teacher, in a well-ventilated space away from other flames, with the gas lit at the burner and never near the tank. Students should not light the gas themselves.
What happens to the leftover slurry?
The digested slurry, called digestate, keeps most of the nutrients of the original waste and smells less than fresh dung. It is widely used as an organic fertiliser on fields and gardens.
Last Updated: September 2026
