Water hyacinth was freshly harvested from Ibiteinye Integrated farms ltd by a worker and the experiment commenced on Monday 1^st, July 2019. Samples of the plant excluding the leaves were reduced using a knife then shredded thrice with an improvised machine cassava grater (Larsen et al., 1991 and Moorhead and Nordstedt, 1993) to improve its density to a higher value as well as to increase the active site for higher microbial action on it during digestion.

One (1) single 120 litres of improvised rubber cylinder can was used as an anaerobic digester. The biogas digester consists of a control valve for biogas flow regulation and a thermometer attached on the cover for temperature readings. (53.9g) of the shredded biomass and 6 kg of cow dung obtained from an abattoir at the marina junction, Eket was used. Three (3) litres of water were added for the 30 days retention time. The cow dung was mixed with water at a ratio of 3:1. The slurry of cow dung and water hyacinth was then fed to the digester for the fermentation process to begin. Experiments were carried out during the cool season and dry season (20– 40◦C).

The metal cover that slides into the hydraulic joint hermetically seals the mixture. The gas was collected and stored in the gas bag. The volume of biogas was measured using an EL- STER HANDEL GMBH MAINZ volumetric meter, which has a limit of detection of less than 0.0010m₃.

The products obtained from the anaerobic digestion of water hyacinth were biogas and the compost that is removed from the digester at the end of the digestion process. The compost is an organic fertilizer having the appearance of farm manure and proven agronomical value. In the case of biogas, the digester and water container were rotated daily so that the heat is evenly distributed. The facility was raised on metal stools so that it would not be in contact with the floor and absorb cold.

For biogas, the starting material and the process (fermentation, digestion or other) usually dictate the compound list and/or method/analysis requirements. Anaerobic digestion produces biogas as a result of its degradation of organic matter. Biogas composition is mainly methane (CO₂, 25-50%), with the remainder being nitrogen (N₂), hydrogen (H₂), oxygen (O₂), and traces of Hydrogen Sulphide (H₂S) and ammonia (NH₃). These two trace gases are responsible for the odour of the biogas and their concentration levels depend on the nature of the feedstock and process conditions. They can be removed from the biogas using scrubbers with adsorbing materials. The energy content (Lower Heating Value, LHV) of methane is 35.8 MJ/m_3, and the LHV of biogas as a whole can range from 21.3 to 23.4 MJ/m_3, depending on its methane content. Biogas is commonly used in Combined Heat and Power (CHP) processes to produce heat and electricity, depending on the digester and the climate of the region the facility is located at. It can be upgraded to biomethane for the production of Compressed Natural Gas (CNG) and liquefied natural gas (LNG), which have similar energy properties as fossil-fuel natural gas and can be used as transportation fuels. It is estimated that 1172 m₃ of methane is equivalent to 1 tonne of oil equivalent.