Trbovlje/Slovenia
Neurath/Germany

Wet limestone flue gas desulphurisation

A proven and cost effective system

Flue gas desulphurisation units have been successfully planned and built since the 1970s, mainly for power stations. Furthermore the expertise of an experienced workforce is behind the innovative AE&E scrubber design, which stands out for its reliability and high availability. Plant economics have also been optimised, assuring low investment and operating cost. An extensive list of references confirms the satisfaction of our customers. These are the main reasons why AE&E limestone FGD is one of the world’s most widely used processes.

Limestone-FGD – a new dimension

In international terms, the AE&E limestone-FGD sets new standards and not merely with regard to size. At the Neurath power plant (2 x 1100 MW), two AE&E scrubbers with a diameter of 23.6 m are being installed to deal with a flue gas flow of 4.7 million m³/h [stp, wet]. The engineering and construction of what at present is the world’s largest scrubber was only possible due to the use of highly innovative engineering tools and the longterm experience of the AE&E team.

The unique AE&E scrubber design, in combination with the optimum adjustment of the overall system concept to match the wishes and needs of our customers, represents our technological trademark. Technical and economic optimisation guarantee minimum investment and operating cost, as well as the highest levels of availability.

Limestone-FGD – advanced scrubber design

The nucleus of AE&E design is the scrubber, which takes the form of an open spraying tower that has been systematically developed in recent years, using computerised simulation techniques. AE&E has continued intensive development work in this field since 1995 and as a result, the company occupies a leading position in the area of scrubber simulation. This position not only allows us to simulate flow and temperature profiles, but also to calculate the distribution of SO₂ concentrations in the scrubber. During subsequent comparisons with actual plant measurements, the flow and temperature profiles have verifed the design parameters.

The result is optimum scrubber design, which is characterised by minimum dimensions, adaptable scrubber entry and exit geometry, and the optimum layout of the spray nozzles and spraying banks. This enables the achievement of a uniform SO₂ profile in combination with the highest possible superficial velocity in the scrubber, whereby maximum removal efficiences are attained with minimum power consumption.

Besides optimum technical design, AE&E gives high priority to the use of the latest materials and construction methods. GRP absorbers and reinforced concrete absorbers with polypropylene linings are used in addition to the proven steel absorbers with a variety of inner linings or stainless steel.

Key features

• An outstanding reference basis for all fuels (lignite, hard coal, oil, biomass, waste)
• SO₂ removal of over 99%
• Maximum HCl and HF removal levels
• Gypsum as a saleable end product
• Flue gas volume flows of up to approx. 5,000,000 m³/h [stp, wet] per scrubber
• Limestone as a favourably priced absorption agent
• Low operating cost and power consumption
• Open spray tower, low pressure loss
• A variety of materials are used (high alloy, carbon steel with rubber lining, concrete with PP-lining, glass fibre reinforced plastics)