Operations & Experience of the “Ecopro” Cambi Co-digestion Plant, Norway
Sargalski, W., Cambi AS, Norway
(free)
This paper describes the operations and experience of the Ecopro Cambi co-digestion plant, including waste quality problems and minor process difficulties that occurred and how we dealt with them. Technical optimisation is a continuous process and is our main focus. We have started to collect some data regarding energy and mass balance, however this program will be fully implemented from November 2008. The paper will also briefly describe the waste management system in Norway and how the country is meeting the challenge of diversion of biodegradable waste from landfills, as called for by Norwegian regulation.
In 2007 each person in Norway produced 429 kg of waste, of which 1/3 was biodegradable referred to as “biowaste” throughout the paper, not counting paper & carton. To meet the upcoming ban on 1 July 2009 of landfilling organic waste several municipalities have for several years implemented source-separation of such waste either to go to composting or to anaerobic digestion. However local composting solutions have been dealing with odour problems for many years.
Ecopro was established on 14 August 2002 by 50 municipalities and serves approx. 230,000 inhabitants. Most of these municipalities have been using landfills to dispose of the produced waste. So for that reason the main driver behind Ecopro’s establishment was regulatory pressures on waste disposal (EU landfill directive) implemented by Norwegian Authorities.
However, also increased focus on renewable energy and the implementation of Animal ByProducts Regulation (ABPR EC 1774/2002) were important drivers. The overall objective was to recover the maximum resource value from the diverted waste while following legal requirements, best available technology and environmental principles.
The Ecopro is a “Green-Field project” and the location was chosen very carefully by the client, hence the plant is located not too close to neighbours. Odour issues and local opinions were handled very seriously by the client. The client was also very focused on building a modern AD plant with minimum odour problems, an objective met by the project.
The project started with a pre-qualification in early 2004 followed by a tendering process where the pre-qualified participants where invited to submit an offer. After this process Cambi was awarded the contract in Dec. 2004, in a two-stage process commencing with a detailed engineering phase followed by contract award in June 2006. The preparation of the Environmental Impact Assessment Report also started at the same time. After 18 months of construction the plant was mechanically complete in March 2008 and is currently in the commissioning phase. The plant builds on the experience from the Cambi biowaste plant at Lillehammer, which has produced biogas and bio-fertilizer for the last 7 years.
Cambi is one of the first suppliers to design and build a commercial co-digestion plant according to the ABPR regulations.
KEY WORDS
Animal By Product Regulation (ABPR), Bio-fertiliser, Biowaste, Biogas, Co-digestion, Sludge,
Thermal Hydrolysis
