To meet the needs of future growth in the township.  HRC recently prepared a project plan and has now begun design for State Revolving Fund (SRF) loan for the digestion system expansion and improvements.  The Township will also receive a $500,000 S2 grant through the SRF program to fund the preliminary project and design engineering costs.

The digestion system will be improved to provide Class A biosolids and will generate electrical power for use within the plant.  Class A biosolids meet the most stringent United States Environmental Protection Agency (USEPA) requirements for stabilization of the biosolids.  This allows more options for ultimate use of the biosolids than farmland application, the typical use of less stringent Class B biosolids.

The anaerobic digestion system will be a Two Phase Anaerobic Digestion (2PAD™) system process by Infilco Degremont, Inc.  The process will use two thermophilic anaerobic digester tanks with 2 days of retention time operating at a temperature of 131°F, and two mesophilic anaerobic digester tanks with 10 days of retention time operating at a temperature of 98°F.

The anaerobic digestion system improvements also include the provision of a Combined Heat and Power (CHP) system.  The CHP system will use the methane gas produced during anaerobic digestion as a fuel to power microturbines.  The microturbines will create electrical energy for use at the wastewater treatment plant.  Initially, 60 kilowatt (KW) of electrical energy will be created with up to 120 KW available in the next 10 to 20 years.  The operation of the microturbines also creates a significant amount of heat which will be used to heat the thermophilic and mesophilic anaerobic digester tanks thus eliminating or significantly reducing the amount of natural gas used for heating the digester tanks.