The population is constantly growing, therefore, the amount of sludge produced by wastewater treatment is forever increasing. Improving the quality of the sludge is essential, as it can be used as a substitute for fossil fuels.

Throughout the years, we have treated sludge and thrown it away because it is seen as a liability and not a resource. Researchers at The William and Cloy Codiga Resource Recovery Centre believe that sludge could actually be a valuable resource and are working on ways to change our minds about how sludge should be treated.

The recent California drought identified a growing interest in wastewater reuse, to supply water resources for drinking water, as well as non potable uses like flushing the toilet.

Wastewater has a wide range of embedded resources such as nutrient, materials and energy. There is already a range of technologies that utilise this resource, but there are many still being developed. The William and Cloy Codiga Resource Recovery Centre allows researchers to use three different grades of wastewater to test different technologies, such as new membrane bioreactors or reverse osmosis processes.

What Other Resources can be Recovered from Sludge?

A traditional viewpoint is that wastewater is hazardous waste which needs to be dumped. However, we need to change this view. Wastewater contains water, nutrients, energy and materials, so you will be able to produce high-end materials from it - particularly, if you have fertilizers such as phosphorus and nitrogen. All you have to do is remove the impurities.


The production of nitrogen fertilizer consumes a vast amount of energy and produces a large amount of greenhouse gas emissions globally. However, in wastewater there is a free supply of nitrogen and phosphorus which could be recovered in a safe way.


Labs in Stanford, US have developed a process where methane, the biogas produced from the anaerobic treatment of wastewater, can be turned into a biodegradable plastic. In contrast to regular plastics, at the end of its life it can be recycled, sent to landfill where it will biodegrade or sent to an anaerobic digester where it can be turned right back into methane gas to make more plastic.

PlasticsThe labs in Stanford are commercialising technology to produce bioplastic from that methane. Research is also being carried out to show that this bioplastic can be used as a supplement in aquaculture to boost an organism's resistance to different bacterial infections, enabling them to reduce the amount of antibiotics that need to be used and, in turn, increase yields.

Belmar Technologies design, build, install, commission and service complete industrial wastewater treatment systems for a wide range of sectors. For more information or to discuss our services further, please feel free to get in touch either by email to or by calling +44 (0) 1327 586 008.