4.2 Discussion
The basis of this study was to explore the possibility of producing biogas with water hyacinth and using it, instead of firewood for cooking which has been proven, as confirmed by certain authors (Chanakya et al., 1993; Kivaisi and Mtila, 1998; Singhal and Rai, 2003; Kumar, 2005). In this study, Biogas outflow was clearly related to seasonal variations in temperature. For the same retention time, the total volume of biogas obtained during the warm season was greater than that obtained during the cool season.
The biogas produced was flammable, combustible with odor, and on combustion produced blue flame indicating the presence of methane. This odor can be attributed to the presence of other gases such as H2S. The study thereof revealed that the higher the dilution level and presence of cow dung, the higher the biogas production yields. Thence, the production of biogas from water hyacinth can serve as a sustainable control measure for managing weed proliferation. Additionally, the slurry can serve as a rich fertilizer for crops.

4.2.1 Observation