Mrs. Chioma Nina is a Chemical Engineer and the Technical and Project Engineer of Avenam Links limited, she specialises on Environmental Engineering and an expert in Biogas Technology. In this edition of Shippers’ Guide with Emeka Chukwuaku, she explains what Biogas stands for and how it can serve as a supplement for electricity. Read on.
What is Biogas Technology?
Biogas technology is the production of gas by using organic materials. The gas got through an anaerobic process. It involves the digestion of organic materials like grass silage, Cow dung, Kitchen waste, food waste; of course you have to make sure that no inorganic materials like Bottle, Bones nylons is found among the waste. Every other organic material can be used for biogas production. So, it is basically the production of gas through biological process. The gas contains methane, CO2H2S and several other gases but the prominent gas is methane and methane is the gas that burns in blue flame. It can be used as cooking gas and to generate electricity. Biogas Technology gives you two things, the biogas and organic slurry which can be used as liquid fertilizer or solid fertilizer when separated. It is used for agricultural purposes in place of chemical fertilizer. It is also a way of removing waste from the environment.
How many Biogas plants do we have in the Country?
We have several biogas plants right from the mid-80s, there were biogas plant in Kano, there were some at Nsukka, Ibadan and here in Lagos but of course not functioning. We have few that are functional like that of PRESCO Company which became operational some months back.
What is the process of converting waste into power?
In a simple way, it is a digestion process just like when you eat food it has to be digested, after that you pass out the waste. The Body absorbs the beneficial ones and passes out the waste. If you are using the Cow dung, what you do is mix it with water, put it in an airtight container; then micro-organisms inside the waste will start their activities of decomposing the waste. As these activities are going on, they are producing gas. A very simple example is when you pass along a dump side, you will perceive some odour, those are gases of which you have methane, H2S that have rotten egg smell and several other gases in minute quantity but methane is more prominent. When you place the waste in an airtight environment it produces gas and liquid slurry which is a rich fertilizer for agricultural purposes. The gas is collected through a gas pipe and channelled through other equipment where you will make sure that there is no water. You will also remove H2S to prevent corrosion and purify the gas that is if you are using it for electricity production unlike cooking you will remove excess water and pass it through your cooker. But for electricity, after you must have removed water and H2S, you pass it through your Generator. So as long as you put waste through that process it will continue to give you gases that will be purified through a simple process that goes into your generator then you have your electricity.
Does Biogas have specially made generators or normal generator we use?
There are generators that are specifically made for biogas or the diesel generator can be converted to that purpose too.
How much waste is needed to power a three bedroom house?
When it comes to biogas plant construction, proper sizing is very important. Proper feeding is also very important. You make sure you don’t over feed or under feed. It is even better to under feed the plant than to over feed. For three bedrooms that have six to eight people living in it, the human waste can be used. The waste is channelled into a digester, you will have like two inlet, one from your kitchen and the other one from your toilet into the digester, is channelled maybe into 10cm3 biogas plant can give you like 5cm3 gas and that can cook up to 6hours but if you have a 2cm3 which is the normal one to have for residential home just at the back of your home, it can give you gas that you can use for cooking for about one hour thirty minutes every day from your kitchen waste. If you want something to power your entire electrical appliance, then you need something bigger. There is what is called power auditing. You audit the appliances in your house in terms of their difficult strength; it’s then that you will be able to know the right generator for your house and the quantity of gas to supply to it.
How affordable is this kind of power generation?
It is affordable because now we have other cheaper technology. This technology started in Nepal; there are quite a number of plants there, then China and Germany. That of the Germans is somehow sophisticated. This is because of their climate and their environment. I think the Chinese biogas plant is much more affordable than that of the Europeans. You just have to look for what is best for your locality. What it will cost you to do a 2cm3 German biogas can do a 10cm3 Chinese biogas plant. It is called the Chinese fix dome plant.
What awareness is Avenam creating about Biogas Technology?
We are doing what we can do to create awareness. I have two books that should be ready at least by February to enlighten people more on this form of energy generation; how to mitigate climate change and how to be aware of the changes in the environment. Biogas technology takes care of the methane that otherwise would have been released to the environment. The awareness is not much I agree and as a result, most people still don’t know how the technology works and they want to see proofs before they believe or want to invest in it. This is the reason Avenam links is going out of its way to make the project known to Nigerians. Thanks to the Federal Government who makes this project a reality through the you-win project. The project itself created awareness on its own because it shows that biogas technology has to stay. It shows that it is feasible, viable and can be invested in. We in collaboration with some people have registered the Biogas Association in Nigeria, very soon, the website will be up and running and people can register.
What are the safety precautions in a gas plant?
Safety is one of the reasons I chose the Chinese fix done Biogas plant. It is filled with water after set up and the water serves as a sealiant tp prevent gas leakage. If you have notice, there are also coverings for the plants to notify anyone coming around the area. There are also some cautionary signs like the ‘No smoking’ sign to ward smokers off and of course fire extinguishers. The plant is well sealed because as the gas is coming out, it is channelled through a pipe into the purification chamber and then out into the generator, you won’t have any contact with the gas. The steamers have nose masks, hand gloves, eye goggles and once the waste is inside the digester, you should not smell anything.
What is the way forward for Biogas in the country?
The future is green, it is a green technology, it is an environmentally friendly technology. With more awareness, it will really come to stay in the country. The banks are not all that aware of it. They are sceptical about getting funding for it is somehow difficult.