Mannvit has actively participated in waste management planning for various municipalities including, Reykjavik and many others in Iceland. This work was done per the EEC directive 75/442, wherein all municipalities are obligated to produce a strategic plan on waste management.
The first common waste management plan for all the municipalities in Southwestern Iceland was issued at the end of 2005. In 2006, Mannvit was hired to compare the cost and benefits of aerobic composting, anaerobic digestion, incineration and new landfill sites. After the comparison was finished, in early 2007, the results were used in a revised waste management plan that was issued in 2009.
Participating areas:
Western Iceland - consists of 10 municipalities with approximately 15,000 inhabitants. The quantity of waste was estimated to be 29 thousand tons, of which 14 thousand tons were organic waste.
Reykjanes - consists of 5 municipalities with approximately 19,000 inhabitants. The quantity of waste was estimated to be 22 thousand tons, of which 14 thousand tons were organic waste.
The Capital Area (Reykjavik) - consists of the capital and 7 neighboring communities with approximately 192,000 inhabitants. The total quantity of waste was estimated to be 270 thousand tons, of which 150 thousand tons were organic waste.
Southern Iceland - consists of 11 municipalities with approximately 18,000 inhabitants. The total estimated quantity of waste was 33 thousand tons, of which 22 thousand tons were organic waste.
The number of inhabitants in these areas is estimated to increase to 290 thousand in 2020, by such time the total quantity of waste is estimated to increase to 480 thousand tons, of which 270 thousand tons of organic waste.
The main concern is the organic waste with potential greenhouse gas emissions. According to EEC directives, the landfilling of organic waste must be reduced considerably in the near future and eventually phased out. The waste companies are running out of landfill space and are having problems obtaining permission to open new landfills.
Waste Management Plan
During 2006 and 2007, several methods of treating organic and combustible waste were compared. The objective of the comparison was to determine the best method from an environmental and economic point of view. All the methods considered utilized “best available technology” according to the IPPC.
The different treatment methods, plant sizes and various possible sites were used in a cost optimization model to calculate the most cost effective solution for the area as a whole. This resulted in a waste management plan based on the following premises:
- All landfilling of organic and combustible waste will be terminated no later than 2020
- The hierarchy of waste treatment has been based on the European waste hierarchy
- There are available landfill sites for the next 12 years operation
- Milestones for the next three years have been set
The waste treatment hierarchy is as follows:
In the recycling stage, reusable and recoverable waste is removed from the waste stream to avoid wasting valuable raw materials and to reduce the total amount of waste for treatment.
From the recycling stage, suitable waste is fed to an anaerobic digestion step to make as much biogas as practical from the organic portion. The biogas is purified to >92% methane and used as vehicle fuel to replace fossil fuel.
The remaining waste from the anaerobic digestion step plus another incoming stream of suitable waste is composted in an aerobic composting step. Depending on the selected technology for the composting, reusable and recoverable waste is removed from the waste stream before or after the composting step.
From the recovered waste, e.g. plastics, rubber, wood, etc., solid recovered fuel (SRF) will be produced if economically viable. This fuel can be used to replace coal with subsequent carbon emission reduction.
Some types of waste are combustible but not suitable for anaerobic digestion or aerobic composting. And, over the next 3 years there will be more than 2 million tons of accumulated waste in the Álfsnes landfill. Therefore, a feasibility study is planned for a waste incineration plant at Álfsnes to handle the combustible waste stream, for energy production and to reduce the volume before landfilling.
To further reduce allocation of new space for landfilling, the oldest part of the landfill site will be opened, when the landfill gas production falls off, to burn the remaining combustibles. The bottom ash may be usable for construction purposes, as a top cover layer, or reduced in volume before landfilling again.