Lightweight and compact sludge thickening device offering huge cost savings and environmental benefits

Most Innovative Water & Wastewater Technology of the Year

The Sludge Opportunity

All biological treatment processes create waste bacteria and solids as by-products, known as sludge. Sludge can be a valuable product. Over the years the focus of disposal has been to apply sludge to land as an agricultural fertilizer. This can generate significant revenues, but its greater value today is as a source of energy created through anaerobic digestion (AD).

However, handling sludge has high associated cost, predominantly due to transport. Water and sewerage companies (WaSCs) spend tens of millions of pounds each year on tankers, so the potential savings to be made by reducing liquid sludge volumes are huge. They are also set to receive a separate price control by Ofwat for their sludge activities as part of the Ofwat PR19 price review process.

It pays therefore to invest now in systems which reduce costs relating to transporting and treating sludge.


The SST Solution

The Static Sludge Thickener (SST) is a very compact sludge thickening device developed from the original de Hoxar Spiral Separator. PWS has enhanced the original Spiral design and owns the IPR for the technology. The developments have been specifically targeted at reducing the costs of handling sludge for several applications.

The key advantages of the Static Sludge Thickener over alternative solutions are:

● thick energy rich sludge typically 6% (saving one stage of additional sludge treatment)
● small footprint
● dramatically reduced installation time and lower civil engineering costs
● ease of drain down (if reactive maintenance is required)
● inherently good flow distribution
● lower energy consumption
● low cost to cover for odour control.