Alternatives to spray irrigation of starch waste based distillery effluent Original Research Article

The distillery effluent from a starch waste based ethanol plant has been disposed of by spray irrigation for some time. The alternative methods of disposal are reviewed and their then costs compared for a 50 Ml/year plant. Anaerobic digestion can reduce pollution load significantly but it requires more investment and increased annual cost. Partial solids recovery by ultrafiltration (UF) does not reduce the pollution as much, but results in a byproduct for sale and a payback period of under six years for the extra investment. Further solids recovery by UF and nanofiltration requires a much longer payback period for the extra investment. Further research is required for more economical solids recovery and better value added byproducts.