Name
Full-scale implementation of the microbial hydrolysis process (MHP) technology
Description
Development of the Microbial Hydrolysis Process (MHP) has progressed from research to implementation at VCS Denmark’s Ejby Mølle plant. MHP is simply adding a hyper-thermophilic (75 OC), anaerobic digester (AD) with a 2-day retention time to a conventional AD system. MHP biologically augments any AD system using anaerobic bacteria, like caldicellulosiruptor bescii, to make complex carbohydrates like surplus activated sludge (SAS) and lignocellulosic material, biologically available for conversion to biogas through methanogenesis. Results from additional pilot testing, calibrated process modeling, detailed design, and equipment procurement improve the business case. Pilot studies consistently demonstrate volatile solids reduction (VSR) of 75 percent! Additional pilot test results include biogas production and pathogen reduction. The design now includes vacuum flash heat recovery for energy efficiency and improved dewatering. Enhanced (Class A) biosolids can now be achieved with the flexibility to operate in a pretreatment configuration. The risk of implementing MHP is reduced with the flexibility to operate the hyper-thermophilic AD as a conventional thermophilic or mesophilic AD. Already being energy-positive, adding MHP will increase VCS’ revenues from selling more renewable energy. Increased VSR and improved dewatering will reduce their biosolids distribution costs. Utilities seeking similar high performance will benefit from following VCS’ example.
Authors
David Parry, Jacobs, USA
Per Henrik Nielsen, VandCenterSyd (VCS), Denmark
Cristhian Gonzalez, Jacobs, UK
Maddy Fairley-Wax, Jacobs, USA
Per Henrik Nielsen, VandCenterSyd (VCS), Denmark
Cristhian Gonzalez, Jacobs, UK
Maddy Fairley-Wax, Jacobs, USA