HRS heat exchangers for Scottish and Southern AD plant
5 Sep 2011
London – HRS Heat Exchangers has signed a Euro1.3m contract with Scottish and Southern Energy (SSE) to deliver a scraped surface vacuum evaporator, for its Barkip anaerobic digestion (AD) plant in North Ayrshire. The HRS evaporator system is designed to overcome fouling issues associated with the evaporation of organic digestate.
The Barkip plant will be the first of its kind to incorporate a novel digestate processing stage: Waste heat from the CHP engines is used to concentrate the liquid fraction of the digestate into a nutrient rich liquid fertiliser.
Under the terms of the contract, the HRS technology will enable the Barkip AD plant to process 75,000 tonne’s of waste annually, in a plant setup that produces around 2.5MW of renewable electricity.
HRS’ Unicus Dynamic scraped surface heat exchanger is designed to ensure that any high organic load in contact with hot surfaces does not lead to fouling. This patented technology is said to provide a continuous cleaning to the walls of the HRS evaporator.
For many environmental applications, standard evaporation technologies are not ideal and do not achieve the desired optimum thermal and waste recycling performance, according to HRS.
The HRS evaporator can work continuously with very little maintenance, at times for more than six months, the company claims.
The project was co-developed by Zebec Biogas, which has the specialist enzyme and biological process expertise.
