Swedish CHP plant orders Flow Scanner XL
The Igelsta biofuel plant, operated by energy company Söderenergi, was taken on-line in 2009 and is a modern CHP (combined heat and electricity) biofuel combustion plant. It is one of the biggest bio power plants in Europe, producing 200 MW of heat and 85 MW of electricity yearly. It’s located just outside Södertälje, about 35 kilometres south of Stockholm.
The plant uses a variety of biofuels, primarily renewable forest residue such as tree tops and branches, but also wood chips, saw dust, recycled paper etc.
As with any tightly controlled process using organic biomass as raw material, the inherent properties of the fuel is important. In fact, the quality of the fuel is the main source for quality problems since it has such a large impact on combustion and heat transfer in the boiler.
Today Söderenergi uses a standard sampling method to analyse the quality of their fuel, something that is both time-consuming and imprecise when it comes to inhomogeneous organic materials such as forest residue.
Automatic realtime analysis
The new Flow Scanner XL will weigh and analyse all of the fuel unloaded from the ships supplying the plant with their raw material. This will all be done automatically as the ship is unloaded and the fuel is transported on conveyor belts to the storage terminal. Fully operational, the Flow Scanner XL will measure:
- The fuel’s energy and moisture content.
- The weight (total mass) of the shipload.
- Type of fuel.
- Ash content.
In addition, the Flow Scanner XL will detect any existing debris, such as rocks and metal parts, which could have become intermingled with the fuel – so that they can be deducted from the invoice and separated to avoid further damage and costly production stoppages.
Better biofuel management
The real-time information from the Flow Scanner will allow Söderenergi to calculate the monetary value of the fuel, and provide better information for classifying, fuel mixing, and optimisation of the combustion process. It will potentially also allow Söderenergi to use a higher fraction of cheaper biofuels in their mix.
The Flow Scanner XL will go on-line in 2015.
(Photos by Söderenergi and Siemens).