Thermal Hydrolysis: The Missing Ingredient for Better Biosolids?

Introduction

One of the world's largest facilities in Davyhulme is proving the importance of thermal hydrolysis technology combined with digestion prior to sludge incineration. Bill Barber, Rick Lancaster and Harald Kleiven discuss reasons for the technology choice and results from an energy study measuring inputs and outputs.

The quantity of sewage sludge, an inevitable by-product of wastewater treatment, is increasing worldwide. This rise is fuelled by a combination of a growing and increasingly urbanized population especially in Far East Asia, and increasingly strict environmental legislation. Once treated, sewage sludge becomes a valuable source of nutrients, known as biosolids, which is used in a number of outlets. Numerous studies have shown that the use of biosolids as a fertilizer on agricultural land to exploit its nutrient and other valuable soil conditioning properties is the most environmentally sustainable and appropriate use for the product.

The authors discuss reasons for the technology choice and results from an energy study measuring inputs and outputs.

Read the full article in WaterWorld International.