SU1000051A1 - Method of cleaning oil containing waters - Google Patents

Description

(54) METHOD FOR CLEANING OIL-CONTAINING WATER

The invention relates to methods for purifying ship water from petroleum products and can be used in shipbuilding and can also be used in other areas of technology that require purification of oil-containing water.

A known method for purifying oil-containing water in a filter with a granular load consists in alternating the processes of filtering contaminated liquid and washing the load by supplying washing water and draining the washed contaminants {oil products) l}.

The disadvantage of the method is its complexity, which consists in the need to determine and precisely maintain the optimum rate of flushing, at which an efficient flushing is simultaneously ensured and the entrainment of the load is prevented. This requires the use of special equipment and control of the rate of washing.

The closest to the proposed technical essence and the achieved result is a method of purification of oily water, including alternating filtration processes in a filter with granular loading

and rinsing the filter by supplying wash water L2 3.

The disadvantage of this method is its complexity.

The purpose of the invention is to simplify the cleaning process.

This goal is achieved by the fact that according to the method of purifying oil-containing water, which includes filtration and washing processes, the filtration level in the filtration process decreases the level of the filter, in the washing process the filter is filled with washing water and accumulates an oil product layer in the upper part of the filter, and then partial discharge of petroleum product.

The decrease in the filtering process

20 level of water in the filter before the formation of an air cavity above it with a volume equal to the volume of water supplied to the washing contributes to the process of washing the load without draining

25 of the fi rm of the wash water, which eliminates the possibility of carrying out the granular load and the need to accurately maintain the optimum speed of the spray, using the upper

30 retaining grids that require an hour of cleaning and replacement, and simplifies the process. The accumulation in the rinsing process in the aforementioned cavity of the wash water prevents the granular load from being carried away with the flushing water, which eliminates the need to precisely maintain the optimum rinsing speed, use the upper retention mesh that requires frequent cleaning and replacement, and simplifies the cleaning method. The termination of the discharge of petroleum products until the filter reaches a layer of at least H in size, .jyipe separated from the relation where 5 is the cross-filter area,, is the water content, c is the viscosity of the oil product, fg is the water area, p (, - the density of oil products contributes to the creation of the interface between two media with different physical properties, as a result of which granules of granular load, carried away by the flow of washing water, cannot enter the layer of oil products, which are greater and less dense than water. Thanks to this weighted in The loading granules are retained at the interface of the indicated media, since without the use of the upper retention mesh, they are prevented from being removed from the filter. This simplifies the cleaning method. Fig. 1 shows a vacuum filter diagram explaining how to clean the oily water in the process. filtration of polluted water1 in Fig. 2 - the same, in the washing process the Scheme contains pipe 1, filter loading 2, pump 2, device 4 for maintaining the level, layer 5 of oil products, pipe b of oil products, sensor 7 of media separation, air w cavity 8, the wash water supply pipe 9. The method is carried out as follows. During the filtration process, the contaminated water enters the filter through the nozzle 1, passes through a layer of filler load 2 consisting of granules of synthetic material with a density greater than the density of water, and is pumped out by pump 3 through the device 4 to maintain the level. At the initial moment of the filtration process, after the next flushing of the loading, a layer of washed petroleum products is located in the upper part of the filter between the nozzles 6 of the oil discharge and the sensor 7 of the media separation. . In the process of filtration, the level of liquid in the filter (the boundary between the cf oil product and water) is reduced to the formation of an air cavity above it by an 8 volume equal to the volume of water supplied to the flushing. The reduction of the level can be accomplished by installing the device to maintain the level of a known construction at a given distance from the oil discharge port b or by supplying air to a vacuum filter until an air cushion is formed and the level is reduced to a predetermined value, or by other known methods. During the flushing process of the load (, FIG. 2, the pump 3 is stopped and the water is fed to the flush through the nozzle 9. Water passes through the load 2 loosens it, puts it in suspension and washes the petroleum products adsorbed on the loading granules. Prog / water from the filter is not drained, but accumulated in the AIR 1 cavity 8. At the same time, the water level in the filter rises, and the washed oil products float up, are attached to layer 5, increasing its thickness. The loading granules transferred to the suspended state are distributed in the volume ... water. However Thanks to the presence of., the boundaries between which the upper medium (petroleum) has a viscosity is greater and the density is less than that of water, loading granules with a density greater than the density of water cannot enter the petroleum product layer and remain at the interface which eliminates the need to accurately maintain the optimal flushing speed, using the upper retention mesh and simplifies the method of purifying oil-containing water. After filling up the air cavity 8, drain the washed oil 5 through the nozzle b. The drain is stopped when a layer of oil products with a thickness of at least H, opposed to, remains in the filter. ratios H, where S is the cross section of the filter, is the viscosity of water, the viscosity of the oil product, p is the density of water, 5 is the density of non-product. The indicated thickness of the oil layer is determined experimentally and excludes at any cross section of the filter and at any effective speed of washing the deformation of the layer of oil products by the wash water flow and the entrainment of granules of the granular load. The control over the thickness of the residual layer of petroleum products can be carried out automatically using the sensor 7 of the media separation, installed below the nozzle 6 by the value H, When the oil-water-water interface reaches the interface.

Claims (3)

Claim The method of purification of oily water,. including alternating Filtration processes in the filter with a grain loading and filter flushing. by supplying washing water, characterized in that, in order to simplify the cleaning method, 5, the filtering process reduces the liquid level in the filter, during the washing process, fill the filter with washing water and accumulate a layer of oil in the upper part of the filter, and 10 then partially drain the oil.