Daily and spatial generation of palm oil mill effluent in determining volumetric capacity for bio-methane planning

Cumulative determination of wastes generated per day and in different periods is a necessary prerequisite for planning waste recovery and averting environmental degradation. This study examined palm oil mills (small, medium and large-scaled mills) in the oil palm (Elaeis guineensis) industry at Ohaji/Egbema Local Government Area (LGA), Imo State, Nigeria for daily and periodic generation of palm oil mill effluent (POME). Survey research design was used. Eight catchment communities of the large-scaled mill, Agricultural Development Authority Palm (ADAPALM) were categorised into three strata in relation to the number of small-scaled mills in each community. In each stratum, a community was randomly sampled. Nine small-scaled mills were sampled from the three communities using proportional sampling. The lone medium and large-scaled mill in the study area represented the other scales of milling. For small and medium-scaled mills, the volume of POME generated was measured from the dimensions of the vessels where POME was stored, while that of large-scaled mill was obtained from industrial records. Independent sample T-test revealed an average of 17.574±0.408m3 POME/day and 15.509±0.465m3 POME/day in wet and the dry seasons respectively (p˂0.01). Similarly, within milling-scales, ANOVA and T-test showed that significant variations occur (p