Cleansing process granted US patent

A university environmental biotech firm that is attracting interest from major water companies has secured its third United States patent.

Advanced Bioprocess Development (ABD) is said to have perfected an innovative process for converting toxic ammonia in wastewater to non-toxic nitrate, which could lead to waste treatment at a fraction of the current cost.

The spin-out of Manchester Metropolitan University was granted its first patent in 2003 – for a nitrification process that uses bioparticles (biofilm on glassy coke particles) to oxidise ammonia, as well as remove dissolved organic matter and suspended solids from wastewater.

Two subsequent inventions – a biofilm control device and a moving bed distributor – were also granted patents.

Research microbiologist and ABD managing director Dr Mike Dempsey said the industry needs constant improvements in its techniques for water cleansing.

‘Our wastewater in the 21st century contains all sorts of new substances that have their origin in medicines and personal care products,’ he added. ‘So there is a real issue around effective clean-up of used water before it can be returned safely to the aquatic environment.

‘The pressure is very much on water companies to be more effective and to reduce costs. In our process, dissolved organic matter and suspended solids are removed by microorganisms and are thus destroyed biologically.

‘Our innovative technology, which has a much higher concentration of active biomass than present systems, can treat up to 10 times more wastewater than a plant of the same volume using current technology.’

The current nitrification process is not only useful for municipal wastewater treatment but also treatment of other wastewaters that contain toxic ammonia, from sources including aquaculture and industry.

A pilot-scale feasibility study has been conducted at United Utilities’ Davyhulme plant in Manchester.