BioReact AD boosts biogas 32%, lowers NG use 10% at 55-MGD WWTP
• Biogas generation: +32 percent (212 MWH/month)
• Natural gas consumption: -10 percent (221 MWH/month)
• Volatiles Solids (VS) reduction: +10 percent
• Total Solids (TS) reduction: +9 percent (2.82 dry tons/day)
• Gross savings: $22,000 per month
The 55-MGD wastewater treatment plant has been a leader in the use of renewable energy for wastewater treatment. It currently generates 95percent of the energy it uses from onsite biogas, purchased natural gas, and solar energy generation. Only 5 percent of its energy requirement is imported from the local power utility.
Dryletʼs innovative technology draws from material science and microbiology. Its BioReact AD product is comprised of carefully selected beneficial microbes embedded inside non-toxic particles made of an engineered porous media substrate. The particles are approximately 200-600 µm in size. They protect the microbes, allowing them to thrive and replicate fast so they can be effectively integrated into microbial ecosystems.
BioReact AD was added to the digesters starting in November 2018 with a daily dosing of 50 lbs. The goal was to boost biogas and enhance solids reduction. The demonstration took place over 90 days. Training was provided to facility personnel on the best points of product application.
BioReact AD was fed to both the 10 primary and 3 secondary digesters in varying amounts, totalling 50 Ibs per day (one of the secondary digesters was offline and under maintenance during the demonstration period.) The sludge-feeding arrangement into the secondary digesters is as follows:
Primary solids and thickened WAS are mixed in a sludgeblending tank prior to being fed into the primary digesters. During the feeding of solids into the 10 primary digesters, the overflow of the corresponding quantity of fed raw digester solids (primary digestate) flows into the connected secondary digester. A single feed point was used for all the primary digesters. The overflow from three selected primary digesters (PD3, PD5, PD11), was used for applying product dosage into the secondary digesters.