'Waste project developers like to view the Organic Fraction of Municipal Solid Waste, as a clear cut portion of harmless kitchen leftovers that miraculously turns into valuable fertilizer. Well, that is a myth' said CBE's Heinrich Seul in his presentation, fully packed to the last seat, during the Biogas Asia Pacific Forum in Kuala Lumpur April 18, 2018.
Seul: 'In practical terms MSW 'Organics' typically are the 0-50mm rejects from mechanical MSW processing, while household waste - post consumer waste from private residences - might account for less than half of total solid waste volume collected by a SE Asian municipality. Seul: 'This material is the concentrate of the central trouble makers in MSW: greenhouse gas emission, soil and water polluting leachate, biohazards, odor.'
Besides the little researched contamination with harmful bacteria and viruses, the biogas infeed material carries heavy metals and biotoxic chemicals in concentrations sometimes by factor 1,000 higher than what is legal for industrial effluents. Biogas creation is low, inhibited by toxic pollutants, biotoxic nitrogen levels and a massive sedimentation of contained solid non-organic particles like minerals from city street sweepings. The resulting digestate might in fact rather be hazardous waste than a fertilizer product meeting legal standards. Seul:' In our projects we urge project developers to lab analyze pollutants content and legal product liability before even considering digestate a revenue stream.'
CBE develops waste projects using MSW biogas in two ways. Case 1 - as a cost recovery strategy in engineered MSW leachate treatment systems in landfills, transfer stations or Waste-to-Energy plants. Case 2 - as stand-alone for loads of 50 tons per day MSW or off-grid locations using thermophilic dry fermentation systems with a 56°C process temperature, because of higher process stability and the fact that the resulting digestate is pathogen free'. The presentation paper is available at info(at)cbethai(.)com
Photo: Fabian Teja Boegershausen - All Rights Reserved.
H. Seul, CBE, Presentation on 'Biogas from MSW Organics - Challenges and Solutions', Biogas Asia Pacific Forum, April 18, 2018, Sunway Putra, Kuala Lumpur, Malaysia
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