Water management is enormously important in the present day for the sustainable use of water as an essential resource. Various treatment processes can be used to help remove impurities from waste water, thereby preparing it to be used anew. One customer of Röchling Industrial is using Polystone® P CubX® to build the housing for a membrane filter plant for process water treatment.
Some two thirds of the Earth's surface are covered with water, the majority of which is salt water. Fresh water accounts for only 2.5% of the global water supply, and less than 1% of this is accessible to humans. This clearly illustrates the value of water as a resource, and the importance of handling it with care.
The fresh water that we are able to access is used not only as drinking water, but in industry as well. Virtually no industrial process can be carried out without water use. This so-called "process water" performs a variety of functions, including heating, cooling, lubricating, conditioning, and cleaning.
Sustainability, cost-efficiency, and legal requirements mean that process water is fed back into natural or internal cycles. Systematic water treatment processes are required for this to be possible. In order for process water to be reusable, the impurities introduced into it during the industrial production process must be removed.
One commonly employed physical treatment technology is the process of membrane filtration. In this process, the mixture of water and the solid or dissolved impurities contained within is mechanically filtered and separated using a fine-pored membrane. This is termed micro-, ultra-, or nanofiltration, according to the size of the pores used. The choice of membrane material is dependent on the requirements of the process. Where corrosive resistance - especially against concentrated acids and alkalis - is a strong requirement, together with temperature and pressure stability, ceramic silicon carbide is the membrane material employed. The filter housing is also subject to varying requirements depending on the scale of the system and process-specific conditions.
One customer of Röchling Industrial has chosen to build the housing for a membrane filter plant using Polystone® P CubX®. An exceptional filter size of 4,400 x 2,000 x 3,300 mm required a construction material with an especially high level of rigidity. Polystone® P CubX® is an innovative tank construction sheet for tanks based on polypropylene (PP). The special characteristics of the product are provided by its internal grid construction, which combines extremely high longitudinal and transverse rigidity within the sheet. This enables highly stable static rectangular tanks to be built even on a large scale which, if built using standard sheets, would require additional steel reinforcements.
Extensive avoidance of steel reinforcements and the excellent corrosive resistance of PP to concentrated alkalis and acids made an outstanding complement to the characteristics of the filter material used in this project. This convinced the tank builder of the value of Polystone® P CubX® as the construction material of choice for the housing of this membrane filtration system for process water treatment.