METHOD FOR CONVERTING PALM OIL MILL LIQUID EFFLUENT TO A SOLID BIOMASS TO FACILITATE RECYCLING

摘要

A method is disclosed for treating liquid effluent (200) discharged from the palm oil milling process by converting it to a solid biomass (214) with significantly reduced moisture content to make it suitable for recycling either as a biofuel or as a biofertilizer. The liquid effluent (200) may initially be pre-treated using a mechanical separation means to reduce its suspended solids content and/or treated using a steam stripping means to reduce its volatile matter content. Its moisture is then significantly reduced using an evaporating means (207). The concentrated sludge (209) discharged from the evaporating means (207) is mixed with one or more bulking materials (211) frorn the palm oil milling process to increase its porosity. The mixed biomass is then dried (213) using a drying means to produce the solid biomass (214). Drying may be achieved using an external heat source or by biodrying. Drying using external heat source is achieved using a convection dryer such as a rotary dryer or conveyor dryer. Biodrying makes use of the heat generated during the initial stages of composting using either the windrowing technique or in-vessel biodrying technique. The condensate (208) containing the evaporated components discharged from the evaporating means (207) is either treated and recycled back to the palm oil mill or treated and discharged.