Flue gas condensation
An extremely cost-effective method of recovering energy for a district or local heating grid is by condensing the water in flue gases. The amount of energy recovered depends on the district heating water temperature. But it is also possible to improve energy recovery by using a heat pump.
As a rough guide, a condensation installation without a heat pump can increase energy recovery by up to 15 percent of furnace output. The corresponding figure for an installation with a heat pump is just over 20 percent. This can be contrasted with the fact that most waste incineration installations in Europe only produce electricity, and do so at an efficiency of 20–25 percent of furnace output.
Babcock & Wilcox Vølund AB installed its first flue gas condensation system for energy recovery that included absorption heat pumps as early as the 1980s. These systems are still in operation and are working very well.
Sweden and Denmark are considered to be the world leaders in this type of energy efficiency improvement, and we note today an increasing international interest in the process. This is partly as a result of the EU's stricter standards for energy-efficient waste incineration. A condensation system may enable an installation to meet the level requirements of the so-called R1 factor. Flue gas condensation systems also reduce emissions, increase fuel flexibility and have the potential to reduce chemical usage and thus the amount of residual products.
So far we have installed flue gas condensation at more than 35 installations fired by waste-incineration or biofuels. Heat pumps are included in the majority of the systems Condensate water is treated in our water treatment processes to purity levels that correspond to drinking water quality. Our condensing scrubbers are fitted with tower packing and droplet separators in ADIOX® material to eliminate dioxin problems caused by the memory effect.
We provide the following subsystems within the framework of this energy-related product group: