Thanks to funding from the Big Lottery Local Food Fund work on our first test build micro anaerobic digestion system is well under way. The purpose of this section of the website is to share our ongoing experience of developing and operating the system - the blog in the page below will added to over time.
For some history on how we've reached this stage (Phase 1 and 2 of the project), and to access some great reports looking at the the idea of small scale AD in the industrialised world, the technology and biochemistry behind AD and a commercial component guide, start-up procedure and operational manual for a small digester please click here to open up the full page with links to the reports etc.
Micro AD - Project Context and Reports
Since the implementation of the Animal By-Products Regulations, the Community Composting of food waste has been a serious challenge to members of the CCN to the extent that to comply with the legislation, some projects had to stop their activities. A number of members pioneered small scale invessel composting, notably East London Commumunity Recycling Partnership, using Rocket systems. As members had to invest in a system to comply with the Regulations it was felt that small scale Anaerobic Digestion, with it's added benefits was worth serious investigation; but we were up against the received wisdom in the UK that large systems were the only feasible option because of economic constraints, despite the level of investment, planning and long lead time required to build such systems. Encouraged by the fact that there are millions of small scale units all over the world, especially in China and India we started some constructive thinking.This resulted first in an intial report exploring the idea of small scale AD in the industrialised world which can be downloaded here: CCN Biogas Gell report.pdf (148KB)
Funding from the WRAP & REalliance partnership programme - the Third Sector Capacity Building Programme allowed us to get started with a knowledge transfer initiative and look to the longer term aims of a bigger project.
We envisage the project having 4 phases:
For phases 1 and 2 CCN has subcontracted expert help from Lettinga Associates Foundation (LeAF) based in the Netherlands at Wageringen University.
The Phase One report is available to download here: CCN Micro AD report (.pdf 2MB)
The Phase One report, by LeAF, covers the project brief as established by the CCN; followed by the various UK legislation for which compliance is essential. This is followed by a detailed description of the biochemistry behind the anaerobic processes of organic decomposition giving rise to the production of methane, and the way this will occur within a digester. It then discusses the existing micro-biogas producing methods from throughout the world, and their suitability for the UK. Finally it deals with the type of substrate likely to be used by the CCN members and the possible test site scenarios, with reference to a generic decentralized biogas plant with potential associated equipment. A primary aim of this report is to introduce CCN members to the workings of and options for Anaerobic Digestion in a UK context.
The Phase Two report is available to download here: CCN Micro AD report (.pdf 382KB)
This report describes the outcomes of phase 2 of the decentralised Micro Anaerobic Digestion (AD) project by the Community Composting Network (CCN). It describes a conceptual design of a suitable decentralized AD system for the scope specified by the CCN Steering Group, a commercial component guide, start-up procedure and operational manual for the digester. The micro anaerobic digester plant has a volume of 1 m3 and is designed to treat kitchen waste.When operating the digester at a conservative retention time, the digester would process around 25kg kitchen waste/d (approximately waste of 10-15 households), and produce about 3 m3 biogas/d. The overall system includes the digester and auxiliaries. The component list identifies suitable components, possible suppliers, manufacturers, alternative manufacturers and component details.
The second CCN micro Anaerobic Digestion Event was held at the Centre for Alternative Technology on Saturday 10th July 2010. The event demonstrated a small-scale working AD system which set up especially for the day. You can view some of the days proceddings on our you tube channel: http://www.youtube.com/user/CommunityCompostingCopies of the powerpoint presentations can be downloaded here: