№02|2015
DRINKING WATER SUPPLY
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UDC 628.161.2.66.081.63
Specific features of mass transfer of silicon compounds through reverse osmosis membranes
Summary
In the process of siliferous natural water treatment with different mineralization levels in two-stage reverse osmosis units the transfer of colloid (polymer) silica forms through permselective membranes at the second stage of water desiliconization takes place. Based on the results of the studies carried out in industrial-scale two-stage reverse osmosis units an attempt to analyze the results obtained in the model that took into account the efficiency of sediment formation on the active surface of a reverse osmosis membrane was made. The summary of the experimental results on siliferous natural water treatment with reverse osmosis is presented. A physico-chemical model of colloid silicon transfer through membranes is suggested that provides for precoat filtration effects and silicon depolymerization and polymerization processes during the solution passing through the corresponding filtering layers. In case of dynamic phase equilibrium availability precoat filtration results in the increase of dissolved silicon concentration fed on the effective membrane surface and subsequent (backward) recovery of the equilibrium composition in permeate. A proximate mathematical model for stable conditions of mass transfer is suggested.
Key words
sorption , reverse osmosis , natural water , colloid silicon , precoat filtration , membrane transfer
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REFERENCES
- Ailer R. Khimiia kremnezema [The chemistry of silica. Part 1. Moscow, Mir Publ., 1982, 416 p.].
- Tikhonov N. A., Kirshin V. V., Khamizov R. Kh. [On dependence of layer density on the sorbent granule surface at isothermal solution supersaturation in ionite from the concentration of components]. Zhurnal Fizicheskoi Khimii, 2000, v. 74, no. 2, pp. 309–315. (In Russian).
- Khamizov R., Tikhonov N., Muraviev D. Peculiarities of the dynamics of ion exchange in supersaturated solutions and colloid systems. Langmuir, 2003, v. 19, no. 25, pp. 10852–10856.
- Poliakov Iu. S. [Using the phenomenon of sediment formation for improving the efficiency of ultra-and microfiltration apparatus]. Teoreticheskie Osnovy Khimicheskoi Tekhnologii, 2007, v. 41, no. 5, pp. 499–506. (In Russian).
- Gorshkov V. S., Savel’ev V. G., Fedorov N. F. Fizicheskaia khimiia silikatov i drugikh tugoplavkikh soedinenii [Physical chemistry of silicates and other heat resistant compounds. Moscow, Vysshaia Shkola Publ., 1988, 400 p.].
- Venetsianov E. V., Rubinshtein R. N. Dinamika sorbtsii iz zhidkikh sred [Dynamics of sorption from liquid media. Moscow, Nauka Publ., 1983, 240 p.].
- Karelin F. N. Obessolivanie vody obratnym osmosom [Water desalination by reverse osmosis. Moscow, Stroiizdat Publ., 1988, 208 p.].