Obiettivo
The aim of the project is to demonstrate the possibilities of recovering of landfill gas for energy purposes from landfills in Portugal.
Landfill gas will be extracted from a completed landfill site in Lisbon to produce electricity by means of a 500 kW motor/generator plant. Approx. 1/3 of the electicity produced will be consumed on-site in the composting plant, the balance being fed into the grid.
The landfill is 10-12 m deep and contains approx. 950,000 t on partially compacted wastes (60% urban waste and 40% refuse of an adjacent composting plant) what renders the application of the technology demonstrated in project BM/741/83 attractive. Recovery of approx. 600 m3/h of landfill gas can be expected according to estimations of the gas production and according to results from a test pumping.
The landfill gas plant in Lisbon is built on a landfill that has just been completed and contains approx. 950,000 t of waste. The size of the site is approx. 16 hectares and it is 10-12 m deep.
160 extraction wells with a diameter of approx. 50 cm are established. We expected to apply these wells as gas rcovery wells, but a test pumping carried out in February 1992 indicated the impossibility of achieving an efficient recovery system applying these wells. Therefore, they have to be removed down to a depth of approx. 3 metres and then tightened with clay.
The extraction system will be made of approx. 50 wells drilled with a diameter of 0.6 -0.8 m and with a distance of 15-20 m. In the centre of the wells a perforated pipe will be placed for gas extraction and another pipe for pumping out water. There will be filled up with gravel around the pipes.
From each gas well a horizontal pipeline is connected to a container equipped with a gas pump with sucks the gas from the single wells and presses the gas through a transmission pipe to the utilization system. The container also includes a measuring and regulation system which measures the content of methane and carbon oxide for every 15 minutes. Depending on the quality of the gas a motor-controlled valve automatically adjusts the gas flow each well.
The production plant is a CHP (combined heat and power) unit consisting of a gas engine running an electrical generator. The power production is about 470 kW and the waste is about 920 kW. The electricity has to be used in a composting plant and the rest is sold to the grid. The waste heat from the engine may later on be used for drying in the composting plant.
The project is divided into four phases :
- Phase 1. DESIGN : The project will be planned and negotiated with authorities and a detailed project will be carried out.
- Phase 2. CONSTRUCTION : Drilling of wells, establishment of measuring, regulation and pump system in a container will take place. Furthermore,the utilization system with the gas engine/generator system will be established.
- Phase 3. MEASURING PROGRAMME : During a two year period a measuring programme will go on registering the gas flow, gas quality, total energy production and power and heat production.
- Phase 4. FINAL REPORT : The result from the measuring programme will be described in a final report besides other results/experience from the project period.
Programma(i)
Argomento(i)
Invito a presentare proposte
Data not availableMeccanismo di finanziamento
DEM - Demonstration contractsCoordinatore
1100 Lisboa
Portogallo