Objective
The aim is to demonstrate a district heating plant firing wood chips of high moisture content without any influence on the total heating effect of the plant.
The plant furthermore offers the option of firing coal in combination with wood chips for regions where there is not sufficient biomass available for maintaining heat production.
The Kibaek District Heating Plant produces energy in the forum of hot water for the heating of approximately 1000 households. The boiler has a travelling grate of total active area 10.4 m2 with a travelling speed of 2.8 - 28.6 cm/min. The maximum boiler output is 8 MW for confiring of woods chips and coal.
During the demonstration phase, the plant was operated with wood chips and/or coal with moisture contents in the range of 46-63%.
In all cases, the measured and calculated efficiencies were high (>90%).
Corrosions problems in the economiser resulted in partial shutdown and these were overcome by replacing the economiser tubes with polyropylene tubes. Corrosion was also formed in the convection part of the boiler and this was solved by increasing the temperature of the return water from 65, 70, 75 deg. C.
The simple payback calculations resulted in 9.3 years although the overall project cost exceeded the original project cost by 40%.
A plant for production of heat using wood chips as its source of energy is established at Kibaek near Herning. The heat produced is distributed to the houses in the town via the central district heating network.
The maximum heating effect is 8 MW resulting in the present oil supply of the heating plant being totally replaced. Furthermore the consumption of coal will be considerably reduced as the boiler operates as the basic heating unit all year.
The heat production of Kibaek District Heating Plant - with the planned connections - amounts to approx. 130 TJ/year.
This is especially so, because coal can be added as supplementary fuel and the system for drying the chips can quickly be adapted to the quality of the fuel.
Environment-wise this project with its integrated flue gas purification system minimizes emissions of dust and other pollutants. Furthermore, an optimal exploitation of the calorific content of the flue gas is obtained, especially during the winter months.
Call for proposal
Data not availableFunding Scheme
DEM - Demonstration contractsCoordinator
6933 Kibaek
Denmark