Biogas potential determination and production optimisation through optimal substrate ratio feeding in co-digestion of water hyacinth, municipal solid waste and cow dung

Abstract

Modelling and optimisation of biogas production from different substrate mixtures is lagging behind in research and development. Current biogas production processes are not fully exploiting co-digestion of multifaceted biomaterials with manures and other biowastes. A model is presented for the determination of biogas production potential from Water Hyacinth (WH), Municipal Solid Waste (MSW), and Cow Dung (CD) as well as the subsequent optimisation of the co-digestion mix ratios of these substrates. In this study biogas is assumed to comprise of methane, carbon dioxide, ammonia and hydrogen sulphide. Baseline biogas potential yields of 747.4 ml/gVS , 790.83 ml/gVS and 884.24 ml/gVS were obtained from WH, MSW and CD respectively. A linear programming mathematical optimisation was done. The objective is to find substrate blend ratios in the co-digestion mixture that maximises biogas production. Optimal co-digestion results in percentage substrate blending ratios of 53.27 : 24.64 : 22.09 for WH, MSW and CD respectively in a case study. 1 kg of substrate mixture yields 124.56 m 3 of biogas which translates to 124560 ml/gVS . Co-digestion and optimisation of substrate blend mix proportions increased the biogas output by 157.11%. The biogas fratenity benefits in having an informed optimal co-digestion model that foretells substrate blending ratios.

Enhancing Biodegradability of Coffee Husk and Water Hyacinth using Food Waste: Synergistic and Kinetic Evaluation under Co-digestion

“…This value agrees with the ranges reported in the former review [24]. Using different feedstocks in anaerobic digestion, depending on their C/N ratios, improves anaerobic digestion performance and signi cantly increases biogas generation and biodegradability [53]. Furthermore, biogas production was reduced at the highest/lowest percentage of the C/N ratio due to a higher/lower nitrogen consumption rate from acid-producing microbes than from methanogenic microorganisms [20].…”

“…In this study, the maximum CBY recovered at the optimum C/N ratio was improved by 179.7 and 51.36% when compared with the C/N ratios of 34.46 (mono digestion of CH) and 25.53 (mono digestion of WH), respectively. This improvement is comparable with the study of Kunatsa et al [53], who achieved the best improvement of biogas yield by 157.11% at WH, municipal solid waste (MSW), and cow manure (CM) mixture of (53.27:24.64:22.09) over water hyacinth alone.…”

Impacts of Anaerobic Co-Digestion on Different Influencing Parameters: A Critical Review

“…This fluctuation is owing to the excess formation of volatile fatty acids (VFAs) [19,75]. In the past, in AD, different wastes, such as municipal solid waste, food waste, kitchen waste, and animal manure, were used for biogas generation [50,[76][77][78]. However, recently, attention has shifted to the co-digestion of lignocellulose material with kitchen waste, food waste, and animal manure to generate biogas due to various advantages [14,47,79].…”

Identifying Advanced Biotechnologies to Generate Biofertilizers and Biofuels From the World’s Worst Aquatic Weed

“…Co-digestion has the potential to increase methane yield and reduce the duration of incubation ( Unpaprom et al, 2020 ). Some studies indicated that the use of food waste, cow dung and some other organic waste decreased the incubation to 30 days ( Priya et al, 2018 ; Kunatsa et al, 2020 ). In some cases, microbial pretreatment was used to generate methane from WH.…”