Method of removing volatile organic substances from small water sources by making use of combined pervaporation and microaeration using membranes with nanopores and apparatus for making the same

摘要

The invented method of removing volatile organic compounds from small water sources by making use of combined pervaporation and microaeration using membranes with nanopores, according to the present invention, is carried out that water to be purified enters the water treatment apparatus (4) through the inlet (3) and in the lower section thereof it flows into a module (6) with a bundle (2) of hydrophobic membranes (1) in the form of hollow fibers, which are provided with nanopores (16) and micropores (17) of at least two sizes within the range of from about 10 to about 500 nanometers, where water, contaminated with volatile organic compounds, flows past the hydrophobic membrane (1) bundle (2). Internal pressure of gas supplied inside the membrane (1) fibers is then adjusted to such a pressure value that is higher by tens of kPa to 0.5 MPa than water pressure, whereby air of the membranes (1) starts to escape into water through the nanopores (16) and the volatile organic compounds bind to the gas and are then removed from the purification module (6) and supplied into a gas separator (7) wherefrom the gas is withdrawn via an automatic bleeding valve (13) through the outlet (14). Micropores (17) on the membrane (1) diffuse the volatile organic compounds through the membrane (1) and subsequently the contaminants are removed via a control valve (11) through the outlet (14) from the apparatus (4). Division of air into pervaporation and microaeration is controlled by means of the control valve (11) and water being freed of the volatile organic compounds flows through an outlet (5) out of the apparatus (4). The apparatus (4) for removing volatile organic compounds (VOC) from small water sources by means of combined pervaporation and microaeration using membranes with pores of different size, consists of a compressor (9) for pumping air and mounted onto a plate (15), a purification module (6), control valves (11), (13) and components connecting fragments of the apparatus. The module (6) consists of a bundle (2) of membranes (1) in the form of hollow fibers, wherein the separated fibers comprise nanopores (16) and micropores (17), and the purification module (6) is provided with both a control valve (11) to regulate the amount of flowing gas and a gas separator (7).