The two variants were charged into the 50 liter metal prototype digesters as originally weighed out. The wastes were charged up to ¾ of the digester leaving ¼ head space for collection of gas. The digester contents were stirred adequately and on a daily basis to ensure homogenous dispersion of the constituents of the mixture. Gas production measured in dm3/kg of slurry (35kg) was obtained by downward displacement of water by the gas.