Gas purification by metering of sulfur with LEWA ecoflow packed plunger and diaphragm metering pumps

Flue gas is produced during various combustion processes and can contain different dust particles, oil vapors and acid vapors, carbon monoxide as well as other toxic substances. In order to reduce the environmental impact, arising flue gas has to be purified.

One possibility for flue gas purification is electric filtration. In this process, ash and dust particles are ionized in an electric field. The electrically charged particles migrate to the collecting electrode, where they are discharged. Then they stick to the electrode in form of a dust layer because of adhesive forces. The electrode needs to be cleaned regularly.

To improve the efficiency of the electrostatic precipitator, sulfur trioxide (SO₃) can be added to the flue gas. For this purpose, sulfur is first melted and fed in liquid form into a sulfur burner, where a sulfur-trioxide-air mixture is produced.

This mixture is added to the flue gas. The SO₃ reacts with the fly ash, and thereby changes the electrical resistance of the flue gas. 

The conditioning of the flue gas increases the collection efficiency of the electrostatic precipitator substantially and has approximately the same effect as doubling the filter volume.

By using LEWA pumps, legal emission limits are met and the environmental pollution is reduced. Our progressive and elaborate technology provides an efficient solution in such applications.