Flow Measurement of Sulphuric Acid in Titaniumdioxide Production

Titanium dioxide, a widely used basic chemical for paints, cosmetics, plastics and much more, can be processed either by the chlorine or the sulphate process. By applying the sulphate process, an approx. 24% concentrated sulphuric acid is formed during the production process.

In many cases, the diluted acid is completely reprocessed in separated recycling plants and then fed back into the production process. Such a recycling takes place by concentrating the diluted acid to a certain threshold and then feeding it into several vacuum evaporators - arranged one after another - to subsequently reach concentration levels above 60%.

Systematic inspection and maintenance of the recycling plants has to occur in regular intervals for safety reasons. When the plant is then put back into service, the pumps, which convey the diluted acid flow to the evaporators, are particularly subject to enormous stresses by the rapid rise in temperature. In order to carry out the process as carefully as possible and with the least amount of wear to the pumps, the responsible engineers were looking for a suitable solution for measuring the acid flow to the evaporators.

Given the requirements and the rather big pipe sizes (DN300), flow measurement with the FLUXUS clamp on flow meter proved to be the ideal and practically unrivaled solution for this challenging measuring task. Since the clamp-on ultrasonic transducers are simply mounted on the outside of the GFK plastic pipe, they are not subject to any wear by the aggressive medium as well as the solid particles contained in it.

By retrofitting the measurement point with a FLUXUS flow meter, which was installed during ongoing operation, the plant restart could be optimized effectively, not only in regard to lower wear of the pumps but also in regard to a reduction of the degree of solid particles caking in the heat exchangers which show a negative effect on the overall energy efficiency of the plant.

Advantages

Accurate and reliable non-invasive flow measurement - no media contact
No corrosion or wear and tear caused by solid particles carried in the acid flow
No risk of leakages
Cost-effective retrofitting without any impact on the pipe system and without any interruption to operation
Sturdy measuring system for permanent use in harsh industrial environment