Novel Hydrolysis Stage for High Throughput Anaerobic Digestion

Current commercial Anaerobic Digestion (AD) plants are inefficient, low-tech and large scale,
only capable of reliable operation within a very narrow range of operating conditions. New
Generation Biogas is exploiting research by North Wyke Research into AD and modern
process control technology to develop a high throughput Anaerobic Digester (HTAD). A
significant increase in biogas productivity will radically change the economics of small
Anaerobic Digesters and realise an unfulfilled need for Single Farm AD plants and cost
effective sewage processing by Water Companies. Research strongly indicates that a very
significant increase in biogas productivity can be achieved. A payback period for most
feedstocks of the order of 5 years or less is predicted, significantly less for higher energy
feedstocks.
AD takes place primarily in 2 phases: Hydrolysis during which the feedstock is broken down
into simpler soluble organic compounds and Methanogenesis during which the hydrolysed
feedstock is decomposed and synthesised to produce biogas. Recent laboratory research
indicates that significant improvements can be made in the performance of Hydrolysis in
small reactors on a range of feedstocks through the use of thermal, mechanical and enzyme
pre-treatments. The potential gain in performance arise from operation at lower temperatures
leading to lower plant operating costs and at higher rates leading to reduced reactor size and
reduced capital costs. These when employed with enhanced methanogenesis will lead to
significant gains in biogas productivity. The feasibility study will build on that laboratory
research and aim to demonstrate that the Advanced Hydrolysis results can be reproduced at an
industrial scale and applied within the environment of a highly controlled, high throughput
reactor.
A range of pre-treatments will be tested with a variety of feedstocks. The results will be
developed and then applied in a commercial High Throughput Anaerobic Digester.