Guliienko S. The process of spiral wound membrane modules regeneration.

The thesis is devoted to the objective laws investigation of mass transfer during removal of cake layer formed because of concentration polarization phenomenon from working surface of membrane and to the designing of effective process of regeneration of spiral wound membrane modules. The theoretical principle of process of precipitate removal from membrane surface in spiral wound membrane module was substantiated. The proposed method of regeneration allows recovering membrane flux without loss of selectivity and mechanical properties. The physical and mathematical models of fouled spiral wound membrane modules regeneration using of temperature cavitation phenomenon under subatmospheric pressure were developed. The equations of mass transfer kinetics in system liquid - solid were expanded to marrow conditions in membrane channel. The objective laws of mass transfer during cake layer removal in channel of spiral wound membrane modules were defined experimentally. The results were generalized in a form of dimensionless equation for mass transportation equations coefficient determination. The proposed equation is reliable in a range of Reynolds from 0,4 to 60. The proposed mathematical model was solved using numerical methods. The calculations using mathematical model were carried out and influence of hydrodynamic conditions, process temperature and cleaning solutions volume is determinated. The most rational flow regime is corresponding to Reynolds number values in a range from 15 to 25. The impact of process temperature and cleaning solution volume is negligible. It was experimentally defined that using of temperature cavitation phenomenon promote of increasing of intensity of cake layer removal process from membrane surface in spiral wound module. The regeneration can be carried out using environmentally acceptable cleaning solutions such as desalinated water and solutions of citric acid and sodium hydrocarbonate. The experimental examination of regeneration process effectiveness was carried out. The possibility of membrane flux recover for 90-95% was proved. It was shown by the experimental determination of total resistance to flux through the membrane of clean membrane module, fouled membrane module and regenerated membrane module that increase membrane flux after regeneration has occurred due to decreasing of cake layer resistance. Those results prove the principles of proposed physical model. The influence of technological parameters on mass transfer effectiveness during cake layer removal using temperature cavitation phenomenon was determinated. The methods of process intensification using periodical operating pressure increasing were substantiated. The effectiveness of periodical operating pressure increasing as an intensification technique which allows increase regeneration coefficient in 1,5 times was proved. The factors which influence on regeneration process effectiveness were determinated using experiment planning method. The regression equations were obtained. The recommendations for using of proposed technique of fouled spiral wound membrane modules regeneration under absolute pressure of 0,005-0,009 MPa and operating temperature of 45 °C were developed. The method of regeneration of spiral wound membrane modules regeneration and variants of technological schemes for its realization were proposed. The algorithm of regeneration time and membrane flux after regeneration was developed. The results of investigations were implemented on LLC "Chernivtsi factory of heat-insulating products" (Chernivtsi), LLC "Lucky-pharma" (Kyiv) and also in educational process in department of Machines and apparatus of chemical and petroleum industries of National Technical University of Ukraine "Kyiv Politechnic Institute". Key words: water, membrane module, fouling, regeneration, mass transfer.