Investigations on the Cleaning Agent in A RO Hollow Fine-Fiber Module
This work was carried out to the make-up water for the boilers at the Tabriz power plant in Iran is treated by a reverse osmosis (RO) process.In this work foulants, cleaning agent on the membrane surface were investigated.The results for EDTA and oxalic acid for removal of foulant on the hollow fine-fiber surface, indicated that SDS and Goli cleaner are not suitable. It was concluded that EDTA and oxalic acid are more effective.
Investigation of the Processing Parameters on the Chemical Cleaning of Fouling Lead Layer from Chromium Surfaces by Using an Orthogonal Array Design Method
4 Abstract: In this research, an orthogonal array design (OAD), OA9 was exploited as a chemometric experimental method for the cleaning of chromium surfaces contamination by using an electrochemical cleaner solution that is established upon the redox reaction principle. The influence of cleaning procedure on the removal of lead fouling layer has been investigated by means of SEM/EDAX and ICP analysis. In order to estimate of the main effect of some experimental parameters, we examined the procedure with a statistical method and the results were quantitavely evaluated by the analysis of variance (ANOVA). The OAD estimation of experimental result provides optimized amount of the parameters including, H O 10% (V/V), stirring speed of the mixture 75 rpm 22 and temperature 28°C, to achieve the most cleaned sample, at which the total removal time of 3 g fouling lead layer is predicted only 7 minutes. The prediction has a complete conformity with experimental result achieve at the similar condition that is 8 minutes. Also, the reaction rate constant of the lead bar oxidation at optimum condition was obtained from the ICP spectroscopy data that proposed by Ostwald approximation method. Finally, the results of this study illustrated that the efficiency of the proposed chemometric cleaning method is higher than that our partner sequential experimental technique.
Cleaning and regeneration of membranes in desalination and wastewater applications: State-of-the-art
Abstract Membrane fouling is a major problem in brackish and seawater desalination and in wastewater reclamation by reverse osmosis processes. Proper pretreatment and periodic cleaning and regeneration are the only available and widely used solutions for this problem. A critical review of methods of cleaning and regeneration of brackish water, seawater, and wastewater reverse osmosis membranes is presented. The review covers physical, chemical and physio-chemical cleaning methods, in addition to the regeneration of reverse osmosis (RO) membranes. Recent developments in cleaning and regeneration techniques and areas of research are also discussed.