Download product sheet Reverse Osmosis - Kurita Europe GmbH

water management
process management
Pretreatment
Cleaning of Membranes
© 2012 Kurita Europe GmbH
Kurita Europe GmbH
To achieve a long run length of the RO membranes, it is beneficial to reduce the load
on the membranes as much as possible by using an effective pretreatment of the
feedwater. Depending on the raw-water quality, this pretreatment could consist of
coagulation, flocculation, sedimentation, filtration etc.
Kurita possesses expert-knowledge and has developed special and innovative products
for this application range. On the basis of diverse analytical test-observations
and calculations, such as Silt Density Index, a selection of the best performing
products could already be achieved in the laboratory testing stage.
An effective pre-treatment of water is the basis for a smooth operation of the reverse
osmosis plant. However, it cannot be prevented that fouling processes and scaling
processes on membranes result in a decrease of performance during the time of
operation. This increases the energy demand of the plant while the quality of the
produced water diminishes. The loss of performance results from colloidal and microbiological
depositions as well as from deposits of metal hydroxides. In addition,
deposits of CaCO 3, CaSO 4, SiO 2, BaSO 4, CaF 2 also reduce the yield of permeate.
For this reason, it is necessary to clean the membranes regularly. Specific demands
require individual solutions in the establishment of the proper cleaning procedure.
For this reason, we perform a range of preliminary investigations in order to develop
a suitable cleaning procedure. The following aspects are of importance:
Autopsy of membranes
Performance tests
Analysis of water
Purification test
Analysis of deposits
Energy Considerations Increasing energy costs directly influence the costs of the production of reverse
osmosis water. The energy consumption of the high-pressure pumps play a central
role.
Regular monitoring of the pressure losses across the membranes and the flow rates
are important control parameters that give valuable information on possible scaling
or fouling on the membranes.
A further important aspect in the examination of energy consumption and saving is
the preheating of the feed stream by means of waste heat from other processes as
water temperature has a dramatic influence on the production of permeate.
Best choice for you is Kurita as your partner. Kurita´s engineers look at your plant
as an entire unit in order to achieve the best cost performance in an efficient and
effective way.
www.kurita.de Product Sheet Reverse Osmosis, page 3