Scaling

A bench scale RO process simulator was operated in a batch concentration mode to determine the effects of product water recovery and feed water temperature on flux, rejection, and inorganic fouling by gypsum scale formation for simulated brackish water. As feed water temperature increased, salt reje

A comprising thermodynamic approach is presented to investigate the behavior of saline solutions with respect to CaCO3, CaSO4 and SiO2 scaling in water treatment processes. The Pitzer activity coefficient model is used to describe the aqueous species activities and the corresponding equilibrium reac

Scaling and fouling of membranes are an on-going performance issue for most plants This presentation outlines innovations in speciality chemicals designed to inhibit membrane scaling and fouling and to clean membranes where deposition has occurred. There is an increasing trend to treat recycled wast

Scaling, often due to the precipitation of calcium carbonate, is a current problem in economical and technical life. To study this phenomenon, some experimental procedures have been developed. They are based for example on electrochemical precipitation, use of nanofiltration and rapid controlled pre

Whilst carbon dioxide is water soluble the system is somewhat complex and results in the presence of carbonate anions which interact with cations such as Ca2+ and Mg2+ present in seawater to form insoluble carbonates, especially at high temperatures. In multistage flash (MSF) desalination plants CO2

This study identified the membrane fouling of a two-stage RO process of the Bai-sha brackish water desalination plant facing serious fouling problems. Two membrane modules, one from each stage, were autopsied and diagnosed for the cause for the failure of the RO system. Different morphologies were e

Polyaluminium chloride (coagulant) is a very complex compound. The change in the ratio HCO3/CO2 during coagulation cause a change in pH in the subsequent RO unit (because CO2 is not rejected by the RO membrane), and it was found that this change is constant for any given recovery, e.g. at 75% recove

Over the years the phenomenon of salinization of the soil has become a major problem in areas of low precipitation. For example, in the South-Western area of Israel there are areas of land with high salinity as well as increase of the salinity in the upper layer of underground water. The solution th

Within the lifetime of most membranes some fouling will adversely affect membrane performance and cleaning will be necessary. The cleaning will depend on the type of deposit such as organic fouling, inorganic scaling or colloidal deposition. However strong the circumstantial evidence as to the ident

Mineral scaling prediction in industrial processes involving high salinity solutions at high temperatures remains notoriously intricate, due particularly to difficulties incurred by modelling the thermodynamic and kinetic behaviour of the mineral deposits in such systems. In addition to these comple