No abstract

No abstract

A novel laboratory equipment has been constructed to allow research in the development of solvent-resistant and solvent-tolerant nanofiltration applications. The equipment can control six parallel lines while concurrently feeding different solvents or mixtures of solvents over membrane samples housed in individual dead-end cells. Control feedback between the solvent flow (up to 40 g h–1) and pressure developing over the membrane sample (up to 40 bar­(a)) is realized independently for each line. The feedback enables one to set experiments in either a constant-flow or constant-pressure operation mode. At all times, the temperature of the process (up to 80 °C) is controlled and referenced for an accurate evaluation of the apparent permeability, accounting for changes in the physical properties of the used solvent (i.e., viscosity and density). The test equipment can be employed in long-term operations, initially following changes in the permeability of a fresh membrane during preconditioning (washing, swelling, and/or compacting), with subsequent process studies assessing the properties of the settled polymeric structures relevant in filtration.

No abstract

Reverse osmosis (RO) plays an outstanding role in water desalination worldwide. Performance of this technique depends on membrane fouling and the raw water seasonal variations, especially temperature and raw water salt concentration. Hence, to neutralize the impact of temperature and feed concentration on the performance parameters, the data collected from the brackish surface water plant were standardized through the use of the American Society for Testing and Materials methods. The value of this normalization is to be able to discern the performance variation which is due to the membrane aging and the membrane fouling, scaling or degradation. The present research investigates the real industrial results gathered from the first experience of brackish surface water demineralization by RO in Morocco. The results obtained evidently show that the feed water is subject to serious seasonal variations in terms of feed temperature and feed salts concentration, which noticeably affect the feed pressure, membrane permeability, and permeate conductivity. The standardized permeate flow, standardized pressure drop, and standardized salt passage show that the performance of the plant was steady all over the period of the monitoring and the observed performance decline-was due to membrane fouling.