Gas from a domestic biogas reactor can be used as energy source for lamps. This is particularly useful in areas without access to electricity.
There are various types of biogas lamps available in Indonesia, and all are very easy to operate. A BIRU lamp is not unlike a kerosene lamp, but instead of a fuel tank, a thick rubber hose pipe is connected to the biogas pipeline.
Gas valve is installed in the pipeline to regulate the flow of gas to the stove. This will help achieve an optimum gas usage. Biogas in the pipeline will reach high pressure (indicated by the pressure gauge) when bio-slurry is overflowing in the outlet, which means the gas dome is completely filled with gas. Pressure will drop along with usage of gas. Flow of gas will vary according to gas pressure.
Stove efficiency depends on the pressure and flow of gas. In order to maintain high efficiency, gas pressure and flow rate must be adjusted as needed. This adjustment can be done by using the gas valve.
A leak in the gas valve may occur due to wear and tear of the rubber seal. The seal should be lubricated regularly and must remain in a dry condition at all times. Engine oil or any other lubricants can be used. The valve must be checked regularly to ensure it is not too tight or too loose. Gas valves used in biogas units must have approval from the IDBP.
Biogas flowing within the pipeline may get saturated by water vapor that condensates in inner wall of pipes. If not regularly drained, the water can clog the pipeline and block gas flow.
If this clogging occurs, biogas flame in stove will appear yellowish in color for quite a long time until the water concentration reaches a certain point and will result in gas not being able to ignite at all. To address this issue, a water drain is installed in the lowest point of the pipeline system.
The primary function of the water drain is to collect and retain water drops and vapor in the pipeline, therefore ensuring a regular flow of gas. After some time, the drain will be full; by that time the water in the drain must be regularly pumped out.
Biogas is produced in the reactor and stored in the gas storage dome, then circulated by the pipeline system. Any damages in the system may result in an irregular flow of gas usage..
Pipes used to circulate gas must be of high quality. A galvanized-iron pipe is excellent for this purpose; however high-quality PVC pipe can also be used. All pipes and accessories such as elbows, sockets, tees etc. must comply with standards of BIRU and IDBP.
The use of the mixer is to prepare feed for the reactor by establishing correct mixing between materials (manure and water) which must be galvanized and constructed properly. The mixer is positioned within the inlet tank. A domestic biogas unit must use a vertical mixer of high quality.
The main gas valve is an important element of the biogas reactor. The valve is installed between the main gas-collecting pipeline and the pipeline system. It controls the flow of gas in the whole pipeline system, and must be opened and closed as needed. The valve prevents gas loss due to leaks in pipelines or appliances. With this important role, a leak in the main gas valve is dangerous. A medium-quality valve carries inherent leak risks, so main gas valve used in the reactor system must be of high quality and have approval from IDBP.
Cooking is one the main uses of biogas. The gas from the reactor is used as fuel for the stove.
A BIRU stove is not unlike a regular one-burner LPG stove. A one-burner biogas stove on average consumes 350-400 liters of gas per hour.