Biochemical Methane Potential of Agro Wastes

Abstract

The focus of our work is on anaerobic digestion of locally available agro wastes like coconut oil cake, cashew apple waste, and grass from lawn cuttings. The most productive agro waste, in terms of methane yield, was coconut oil cake and grass. The results showed that the initial volatile solids concentration significantly affected the biogas production. The methane yield from coconut oil cake was found to be 383 ml CH4/g VS and 277 ml CH4/g VS added at 4 and 4.5 g VS/l. In case of grass the biogas production increased with increasing VS concentrations with methane yield of 199, 250, 256, 284, and 332 ml CH4/g VS at 3, 3.5, 4, 4.5, and 5.0 g VS/l. For cashew apple waste single-stage fermentation inhibited biogas production. However, phase separation showed methane yield of 60.7 ml CH4/g VS and 64.6 ml CH4/g VS at 3.5 and 4.0 g VS/l, respectively. The anaerobic biodegradability of coconut oil cake was evaluated in fed batch mode in a 5 L anaerobic reactor at 4 g VS/L per batch, and the maximum methane yield was found to be 320 ml CH4/g VS.

Hydrothermal Carbonization of Biosolids from Waste Water Treatment Plant

“…COD for this ranges from 6000 to 90,000 mg/L [28]. Considering theoretical methane production of 0.35 L/g-of-COD [29], an average methane production of 0.03 Nm 3 /L of process water could be obtained which can supplement the energy needed for the hydrothermal process.…”

Effect of Organic Load and Alkalinity on Dairy Wastewater Biomethanation

“…These authors observed that the greatest biogas volume occurred with an HRT of 2 days, reaching a relative biogas production of 0.280 L CH4.g CODrem -1 . The theoretical biochemical methane potential per gram of CODrem is 0.350 L (Prabhudessai et al, 2013). However, some organic matter is used for growth of microorganisms and maintenance of cellular metabolism (Raposo et al, 2011).…”

Effect of Microwave Pretreatment on BMP of Decanter Cake from Palm Oil Mill Factory

“…However, the rate of biogas and methane productions differs significantly according to the operation of microwave pretreatment for decanter cake at various powers and heating times. The cumulative methane also increases with the increasing of the total amount of organic matter in a substrate after microwave pretreatment (Prabhudessai et al, 2013).…”

“…Total Volatile Solids (TVS) analysis determines the total amount of organic matter in the substrate. Thus, the increasing of TVS can enhance the organic biodegradability and the biogas and methane productions for anaerobic digestion (Prabhudessai et al, 2013). Microwave pretreatment has proved to be an effective way to break down the structure of fiber and lignocellulosic materials such as rice straw and switch grass (Zhu et al, 2006;Hu and Wen, 2008).…”

“…The highest cumulative biogas is produced by the reactor containing the decanter cake pretreated with the 360 watts of heating power and 4 min of heating time (R6). The cumulative biogas increases with the increasing total amount of organic matter in the substrate after the microwave pretreatment process (Prabhudessai et al, 2013). Figure 5 shows the cumulative methane of pretreated decanter cake at the end of the 45-day anaerobic digestion.…”