AeroThermal Ltd has revealed its twin Thermo-Pressure Hydrolysis vessels developed for an Irish power distributor are now onstream and on target to process 90,000 tonnes of household and municipal waste per year.

The 65m³ TPH vessels which were designed, developed and engineered by AeroThermal Ltd in Poole, Dorset, utilise technology which pre-treats food waste and other bio-waste organics prior to going to mesophilic anaerobic digestion.

Christian Toll, AeroThermal’s CEO, said: “The successful operation of our two units is a proud moment for us. Our investment in research and development has come to fruition with technology which will vastly reduce waste going to landfill and help create sustainable fuel, clean recyclables and soil conditioners.”

The two Thermal Pressure Hydrolysis units,(TPH) operate in cycles of 2.0 – 2.5 hours, each processing more than 20 tonnes of bio-waste translating to approximately 90,000 tonnes per year.

The advantage of using TPH units is that they allow the blending and co-processing of bio-waste in one simple process which pasteurises, homogenises and hydrolyses.

The process is initiated with a vacuum, then followed by high temperature saturated steam and this combination creates a process that has the ability to deal with highly cross-contaminated wastes, at the same time as delivering higher gas yields in a shorter period of residency time.

The waste material is hydrolysed and after the process is complete, the product exits the vessel as a pumpable liquid. It is then separated into the predominant organic fraction which goes into anaerobic digesters, producing higher yields of biogas that ‘traditional’ digester systems.

The biogas is used as a fuel source for reciprocating spark ignition gas engines to generate electricity that is exported into the grid.