In a normal Palm Oil Mill, the oil extraction process recovers about 20.65% oil from the fruit but the process discharges 65% of waste water – which requires a large number of wastewater treatment (effluent) ponds to clean.
Being high in Chemical Oxygen Demand (‘COD) and Biological Oxygen Demand (‘BOD’), this waste releases high amounts of biogas into the atmosphere, and contaminated waterways. If not properly treated, this wastewater becomes toxic to life in the rivers when it inadvertently enters it. AQUAECO–SRORS system solves the issue of wastewater by intercepting the raw sludge and separating it into water, solids and oil components.
The system uses an innovative, self-cleaning membrane technology to filter out suspended solids and oil – leaving a clear filtrate with dissolved organics for further processing or recovery. The oil is recovered back as crude palm oil, while the suspended solid is removed as decanter cake in the decantering process.
All oil and suspended solids is stopped from entering the treatment ponds. Without the need to break down suspended solids, pond treatment becomes more efficient, reducing biogas emission and BOD of discharge by an astonishing 70 percent.
The technology can be adopted by mills with or without polishing or with and without biogas capture plants.
- For mills without polishing
- For mills with an existing biogas facility
- For mills without an existing biogas facility
For mills without polishing
For mills without a polishing plant at the end of the ponding system, AQUAECO–SRORS may help the mill to achieve their DOE discharge parameters if the ponding system has been designed to discharge the required BOD values as set by DOE.
This is because the COD/ BOD of the clear filtrate discharged to the pond is only about 60% of its original toxicity, even with EFB Liquor in the raw sludge. For example the ponding system was originally designed for a BOD of 25,000ppm, but with EFB Liquor, the BOD has increased to 50,000ppm. After the AQUAECO–SRORS installation, with a reduction of 70% BOD, the discharged BOD will be about 15,000ppm only. It is still significantly lower than the 25,000ppm and the raw sludge is without suspended solids.
For mills with an existing biogas facility
For existing mills with a biogas plant, oil in raw sludge has been a major issue for the biogas process. AQUAECO–SRORS will help to recover residue oil from raw sludge to increase mill’s OER and at the same time provide the biogas plant with a raw sludge without oil for processing. Suspended solids or decanter cake can be blended back with the filtrate, which is raw sludge without oil, for the biogas plant. Since AQUAECO–SRORS is a revenue generating system where the payback period is within 2-3 years, it is a viable stand alone business investment.
For mills without an existing biogas facility
For mills looking for a Biogas Capture/Avoidance Facility to meet the MPOB directive, Aqua Ecotech is working very closely with MPOB on phase 2 of AQUAECO–SRORS. In phase 2, filtrate will be processed to recover and recycle water for the mill’s use to give the mill zero discharge and provide the mill with a Biogas Avoidance Facility. This will provide the mill with a system that has negligible carbon footprint and a reduced water footprint of about 30-35% only. This will auger well for mills which are facing problems with water quality and quantity. Revenue from oil recovered and savings from desludging and water and waste water treatment will pay for the AQUAECO Plant. This will be the future for the palm oil mill.