ABSTRACT

Addition of metals, i.e. calcium, cobalt, iron, magnesium, molybdenum and nickel individually as well as in combination, enhanced biogas production and this was attributed due to the increase in methanogenic population in the digesters (Seenayya et al., 1992). Raju et al. (1991) observed that addition of cobalt, nickel and iron increased the production of biogas from mango peelfed digester to a level several fold higher than in the control.