In various industries ranging from titanium dioxide, magnesium oxide, pulp
and paper to chemical processing, GEA Messo AG offers complete effluent
treatment solutions. The systems are built for:
- Recycling of reaction components
- Recovery of valuable by-products
- Recovery or discharge of components
GEA Messo AG has supplied worldwide more than 50 plants for various
industries with application of the following evaporation and crystallization
technologies:
- Multiple effect
- Thermal and mechanical vapour recompression
- Evaporative crystallization
- Vacuum cooling crystallization
Typical application of effluent treatment process as example:
Treatment of Waste Sulfuric Acid
The treatment of waste acid from the
production of TiO2 is illustrated as follows.
The production of white
pigment by the older of the processes in use today is based upon the leaching
of ilmenite ore with H2SO4. For every ton of TiO2 product, about 8 tons of
waste or weak acid with approximately 20% sulfuric acid is produced. This
stream which is contaminated with many soluble impurities is treated in a two
stage process. The treated acid can be reutilized for ore leaching. Through
systematic recycling, pollution of the oceans can be avoided.
The most common evaporator and crystallizer types used are: flash,
rising film, falling film and forced circulation evaporator as well as the
forced circulation type crystallizer. GEA Messo AG has extensive know how and
experience in designing the components in special material of construction like
carbon steel, rubber lined, special alloys, graphite, plastic materials such as
FRP, FEP and silicon cast iron etc.