Stadtwerke Lemgo: Boiler feed water for the energy supply

For operational and cost reasons, Stadtwerke Lemgo’s ageing water treatment plant was to be replaced with a modern boiler feed water treatment system.

Treated water for the gas turbine plant
The gas turbine system requires water, which must be specially treated, to be injected into the combustion chambers. High quality pure water. An extremely low silicate content and a minimum residual salt content were required. The water also had to be free of alkali elements and heavy metals. Otherwise there is a risk of high-temperature corrosion or critical deposit formation in the gas turbine part.

Treated water for the district heating network
One particular focus of the water treatment for the district heating network was the desire to reduce ongoing operating costs. Secondly, the ability to react flexibly to changing operating requirements thanks to modifiable system performance.

Environmentally friendly desalination using a membrane process
The experts at EnviroFALK came up with a convincing solution, an environmentally friendly desalination process using membranes. A precisely dimensioned boiler feed water treatment system was designed for this purpose, consisting of water softening, two reverse osmosis systems and mixed-bed ion exchangers for fine water desalination. When designing the system, the experts focused in particular on the desire to save running operating costs. The reverse osmosis systems were equipped with an integrated concentrate stage. By increasing the usual water yield, the reverse osmosis systems not only require less raw water, but the upstream water softener also requires less salt for regeneration.

Treatment of boiler feed water
Magnus Häbel, Key Market Manager for Process Water at EnviroFALK: “Stadtwerke Lemgo is a pioneer in innovative, climate-friendly in-house generation of electricity and heat. Consistently high water quality is therefore extremely important for a high level of supply security.”

A solution was also developed for handling within the confined installation options and space conditions. The reverse osmosis systems were pre-assembled on several divisible stainless steel frames, installed on site and put into operation in the available space.

The EnviroFALK boiler feed water treatment system not only reduces ongoing operating costs. Stadtwerke Lemgo is an exemplary pioneer for innovative, climate-friendly in-house generation of electricity and heat.

Matthias Rabe, head of the in-house generation department at Stadtwerke Lemgo’s Mitte cogeneration plant: “In EnviroFALK, we have found a good and trustworthy partner for water treatment. A company that scores with competent advice, professional implementation and customer-oriented service.”