PROJECT DESCRIPTION
BACKGROUND
In Poland, volumes of solid waste and sewage sludge are increasing, and landfilling is the most common approach to waste management, accounting for 80% of waste disposal. Both municipal solid waste and sewage sludge, however, have high energy recovery potential and according to the EU Directives 2006/12/EC, they should be minimised, re-used, recycled or incinerated with energy recovery before disposal to landfill sites. Other EU countries, such as Austria, the Netherlands, Sweden, Denmark and Belgium have madegood progress in this area. Poland has introduced a ban on the storage of waste with a calorific value above 6MJ/kg and the Polish National Waste Management Plan (2010) requires the complete phasing out of sewage sludge storage from 2013. Implementation of this plan is difficult for small and medium size municipalities, where the volume of waste and sewage sludge is too small to warrant the construction of a waste incinerator. A potential solution is distributed small-scale energy generation from local sources.
OBJECTIVES
The overall objective of the LIFE COGENERATION PL project was to demonstrate the operation of an innovative technology for managing the energy fraction of municipal waste and sewage sludge. The technology consists of a unique gasification process and a highly efficient system for the production (cogeneration) of electricity and heat. Gasification is a method of producing gas by subjecting certain materials to high temperatures (>700C), without combustion, with a controlled amount of oxygen and/or steam. This gas is then used as a fuel. Specific objectives included the construction of a pilot-scale prototype demonstration plant that integrates five technological units: fuel preparation, gasification, syngas purification, syngas combustion and production of electricity and heat, and off gases discharge. The aim was for the plant to have the potential for application on an industrial scale.
RESULTS
LIFE COGENERATION PL developed an innovative approach to the pyrolytic combustion of waste and sludge for the cogeneration of electricity and heat, particularly targeted at small to medium municipalities. The project reached or exceeded all technological parameters, it also increased the environmental awareness of the local community in Poland by carrying out information and promotion activities, and demonstrated the technology to investors, designers, and local and state administrations.
The project beneficiaries designed, constructed, installed and demonstrated a prototype for energy generation from municipal waste and sewage sludge, with alternative fuel forming, gasification process and highly-efficient cogeneration along a single process line. They evaluated and optimised key parameters of individual operations of the technological process. This formed the basis for an Environmental Impact Statement - a document presenting the environmental impacts of the installation (in accordance with the Polish Act, Ustawa z dn. 31/10/2008). An Energy Balance document was produced, for energy flow throughout the whole technological process, while an Economic Analysis document presented evidence for the economic feasibility of the technology. LIFE COGENERATION PL supports EU policy directives concerning waste management and wastewater treatment among others. It also relates to national legislative acts, including the Polish Waste Management Law.
To increase knowledge among target audiences for this newly-developed technology for managing waste, the project team organised 17 national and 3 international (EU) debates/informational meetings, and 15 workshops for the direct demonstration of the technological process. The projects pilot technology enables a reduction of the volume of sewage sludge stored in sedimentation ponds, and therefore a reduction in the land needed for sedimentation ponds, with reduced associated smells and insect nuisance. It will also increase the volume of energy produced from renewable sources. Specifically, the pilot technology reached a processing capacity of 310 kg/h of sludge and waste; 240 kg/h of sieve fraction of the communal waste; 61 kg/h of dried sewage sludge; and 9 kg/h of plastic waste.
The innovative technology, for the management of the energy fraction of municipal waste and sewage sludge, used a unique gasification process and a highly-efficient cogeneration process for producing electricity and heat. The energetic value of the syngas produced was 5.6 MJ/m3. One kg of fuel gives up to 1 kW of electrical energy generation. Heat recovery was 485 kW for every 300 kg of fuel. These results exceeded the initial target parameters.
In terms of socio-economic benefits, the projects environmental survey showed how the pilot installation contributes to improved quality of life and the health of the local population. It will reduce the volume of transported waste, reduce health impacts associated with sludge ponds, and generate local jobs - estimated at 10-15 jobs per installation. The commercial scaling-up of the pilot technology will reduce costs of sewage sludge management and the cost of treating fine communal waste. It will also generate income from energy production. An economic analysis showed that the processing of 20 000 tonnes/annum of sludge and waste per installation is economically viable.
Further information on the project can be found in the project's layman report and After-LIFE Communication Plan (see "Read more" section).
