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Pricey gas? I make mine with manure

Kibuye Waste Management CBO chair Harrison Otieno (left) and Bonface Okwero at the Kibuye market waste recycling center in Kisumu. They produce biogas from the waste. [Denish Ochieng, Standard]

Dear Dr Messo, I am really enjoying poultry farming, ‘hata gas wapandishe’ (even if they increase gas prices), I have free biogas from chicken manure. I encourage your farmers to do the same. [Wilson Indangasi]

Dear poultry farmers

Well done Indangasi for what you are doing. As pressure grows to raise poultry in a more sustainable manner and at the same time retain maximum margins, producers must now focus on the use of poultry manure for economic gains and in protecting our environment.

Poor disposal of this organic waste in the air, water and our soil may result into release of nitrogenous gases and pathogens that can have a negative impact in the environment and increase carbon footprint.  The term carbon footprint refers to the total amount of greenhouse gases (which includes carbon dioxide and methane) emissions caused by an individual, event, service, place, or product which impact negatively on environment. On average, one layer chicken can produce 47-54kg of manure per year. The high organic matter of this manure makes this product an ideal substrate mass for production of biogas for cooking. This deliberate choice will go along way in protecting our environment from global warming.

Russia-Ukraine conflict, the impact on gas prices

The current Russia-Ukraine conflict continues to disrupt gas and oil prices and supply chain globally and Kenya is no exception. As the war continues, economic effects following disruption on trade in gas, petroleum and fertilisers is being felt worldwide. In Kenya today, a bag of fertiliser is retailing at Sh6,000 ($51.7) without subsidy while 13kg gas is going for Sh3,400 ($29.3) in the open market.

So how can poultry manure be used to help alleviate some of these problems farmers are experiencing?

Production of methane gas

Let’s start with understanding what kind of gas is used for cooking. Methane which is commonly used for cooking is a hydrocarbon that produces more energy per unit compared to oil.

It is commonly used for cooking as it has no smell and rarely coats the cooking utensils. It is colourless, odourless and is the main component in natural gas. As it burns, it gives out a pale non luminous flame and, in the process, reacting with oxygen to produce carbon dioxide, water and heat.

There are innovative technologies available in harnessing poultry manure especially from layer flocks into a reactor that will allow anaerobic digestion to convert it into methane gas. This happens in a four- stage process of hydrolysis, acidogenesis, acetogenesis and methanogenesis. This technique is simple, cost effective, sustainable and will save farmers economically. There is no need to throw away poultry manure again.

Most of our commercial chickens are mainly raised in intensive deep litter system, where they are kept indoors and provided with comfortable conditions in form of dry litter, good ventilation, spacious accommodation, natural lights, and good nutrition. If properly taken care of, there is no need to replace litter every week. Let the litter work and form a rich manure that can easily be digested.

Wood shaving is still the best alternative bedding for commercial chickens as it has good moisture holding capacity and is easy to keep dry and friable.

More famers are now being encouraged to pursue this alternative form of burning methane and thus contributing immensely to protecting the environment against global warming, sustainably helping to fuel homes and businesses. 

We do have companies that provide this sort of technology of producing methane using commercially available microbes that are injected into poultry waste composting facilities with pipelines attached to a burner or cylinder. The residue digestrate can then be disposed of.

Turning poultry manure into fertiliser

Chicken manure is very rich in nitrogen, phosphorus, and potassium the three main components of a good fertiliser. Before you apply it in the shamba, it is important that it is first decomposed to kill any pathogens from the previous flocks. The process is easy. Just heap the manure, cover with a polythene bag, and allow to ferment for a few days. The product is then allowed to dry and can be used in the shamba or alternatively bagged and stored. It can also be pelleted and stored for use.

[The writer is the Head Vet at Kenchic Limited, [email protected]]


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