Water consumption and wastewater generation from small-scale crude palm oil extraction in Ghana


 This study assessed water consumption and wastewater generation by small-scale crude palm oil extraction mills in Ghana's Central Region. Twenty-five (25) mills were selected from four palm oil processing local government areas in the region. An interview guide was used to obtain information about the operations of the mills and corroborated through structured observations. Water consumption and wastewater generation were measured using a graduated plastic bucket. Water for processing was found to be sourced from hand-dug wells (56%), treated piped water (20%), boreholes with handpumps (16%) and rivers (8%). Water was bought at US$1.93 (boreholes) and US$2.89 (piped water) per cubic metre. The recurrent cost of water was the same as that paid for domestic use. For a litre of palm oil produced, 0.760–2.391 L of water was consumed and 68–82% returned as wastewater. 68% of the water was used for boiling. The distance to the water source influenced the consumption, with higher water consumption recorded for mills with on-plot water sources. Higher recurrent costs of water did not necessarily lead to lower water consumption. There was no significant difference in water consumption and wastewater production between the wet and dry processing methods.