RU2067081C1 - Plant for purification of liquids from oils and suspended matter - Google Patents

Abstract

FIELD: purification of production sewages. SUBSTANCE: plant is applicable in gradual reduction of concentration of floating oils (oil products) with the help of wire brush in the coarse purification section and unit of obliquely directed plates in section of fine-layer settling, filter element from dusty sawdust with regulator of density of fiber packing in final purification section. Floating oils (oil products) in each section is removed together with thin surface layer of water through unloading holes made in side walls of the plant. EFFECT: higher degree of purification of production sewages from oils (oil products) up to 3/10 mg/l and suspended matter up to 10-15 mg/1, reduced operating costs for water purification and increased filter service life. 1 dwg

Description

 The invention relates to the treatment of wastewater from oils (petroleum products) and suspended solids and is aimed at improving the quality of purified water.

 Known oil trap containing a housing divided by semi-submerged partitions into pre-treatment chambers equipped with a stirrer with flexible blades in the form of ruff counts; a settling chamber equipped with a floating oil gathering screen made hollow with an upper shell of oleophobic material with heating elements in the layer of the upper shell and a lower one of oleophilic material with holes, two thin-layer blocks installed respectively at the beginning and end of the settling chamber and pivotally connected to partitions; chambers of purified water; devices for supply and removal of phases; oil collecting tray.

 The drawback of the oil trap is, firstly, that the agitator with flexible blades introduces additional emulsification of wastewater in the pre-treatment chamber, and secondly, thin-layer blocks installed at the inlet and outlet of the settling chamber, adsorbing oil products on their planes, are a potential source of saturation wastewater with a finely divided fraction of oil products, and thirdly, a high content of residual oil products (more than 5 mg / l) in purified water.

 The aim of the invention is to provide a device that would be simple and reliable in operation with minimal capital and operating costs, which would ensure the purification of industrial effluents from mechanical impurities, as well as oils, gasoline, kerosene, diesel fuel and other floating petroleum products to concentrations of 0.1 -0.5 mg / l of petroleum products (NP) and suspended solids (BB) up to 10-15 mg / l, which is a prerequisite for the reuse of purified water for technical purposes.

 The installation comprises a sewage supply pipe, a housing divided by vertical partitions into a rough cleaning section with a ruff block, a thin-layer separation with a block of inclined plates for collecting purified liquid, an oil pan, and a system for removing sediment. According to the invention, the installation has a post-treatment section located after the thin-layer separation section with a filter element consisting of a layer of wood dusty sawdust, bounded above and below by a fine-mesh stainless steel mesh, a series of small-diameter through holes made in cascade with lowering from section to section in the wall of the installation casing, connected to the L-shaped nozzles directed into the tray.

 Performing a post-treatment section with a filter element from a layer of woody dusty sawdust allows you to purify water from a hard-to-separate fraction of oil products with a particle diameter of 5-10 μm and suspended particles of 10-25 μm in size, followed by their removal through a series of rounded through holes and a tray in the oil sump.

 The interconnection of these elements allows, firstly, to carry out cleaning by gravity, i.e. without additional energy costs, secondly, it eliminates the use of expensive adsorbents, and thirdly, to bring the concentration of residual oil products in purified water to 0.3 mg / l and suspended solids to 10-15 mg / l. The obtained degree of purification allows the use of water not only in the reverse water supply system for washing cars, but also in other technological processes.

 The drawing shows a diagram of an installation for cleaning liquids from oils, gasoline, kerosene, diesel fuel and suspended solids in the context. The installation has a rectangular housing 1, located under the floor of the production room, an oil pan 2, sections 3, 4 and 5, respectively, of rough cleaning, thin-layer separation, after-treatment, and also section 6 for collecting purified water. The oil pan 2 is separated from the sections by a continuous partition 7. Between the sections, paired vertical partitions 8 and 9 are installed, the first along with the liquid having a cut-out for the flow of liquid from below and the second from above. In section 3, a grid 10 is placed on top, a ruff 11 block and a sludge drain pipe 12 with a scraper mechanism are installed. The bottom 13 of section 3 is conical in shape. In section 4 of the thin-layer separation, a block of inclined plates 14 is placed, made corrugated and coated on one side with a paraffin-vaseline mixture. A slurry pan 15 is installed under the plate block 14. In the post-treatment section 5 there is a filter element consisting of a layer of wood dusty sawdust 16, bounded above and below by a fine-mesh stainless steel mesh 17. The purified water collection section 6 is equipped with a drain pipe 18, a float mechanism and an automatic water reuse system for reuse (not shown in the drawing). On top of the rear longitudinal wall of the housing 1, in cascade with decreasing from section to section, a series of rounded through holes of small diameter are made — unloading holes 19, to which L-shaped pipes (not shown) are connected, communicating with a drain tray (not shown inclined to the side oil pan 2.

 Installation works as follows. Wastewater through the feed pipe passes to section 3 with a block of ruff 11, for example, synthetic. Suspended substances are concentrated in the conical part of the bottom 13, from where they are removed by means of a moving pipe 12 connected to the scraper mechanism. Oils (petroleum products) are concentrated in the upper part of the sections and discharged together with a thin surface layer of water through a series of cascade-shaped rounded through holes 19 connected to L-shaped nozzles directed to the tray.

 From section 3, drains through flows in partitions 8 and 9 fall into section 4 of a thin-layer separation. The lower surface of the corrugated plates is preliminarily coated with a layer of paraffin-vaseline mixture. In section 4, the sediment is collected in a pan 15, and oil on the surface of the water. The oils are removed together with water in the same way through the discharge openings 19. In the post-treatment section 5, during the operation of the installation, the untreated water passes through a layer of wood dusty sawdust 16, bounded above and below by a fine-mesh stainless steel mesh. Through partitions 8 and 9, practically purified water enters the purified water collection section 6, from where it is sent to the sewer or is sent through a drain pipe 18 to a car wash and other production purposes.

 A high effect of the installation is achieved, firstly, due to the sequential treatment of effluents in the listed sectors of the installation. The effluent flows into sector 4 of the thin-layer separation with an NP concentration of up to 40 mg / L, the after-treatment section is 5-10 mg / L NP, respectively, and the residual oil concentration is 0.1-0.5 mg / L into the purified water collection section 6. Secondly, the use of a hydrophilic filter element from wood dusty sawdust with pore spaces between individual fibers to 100 microns, reduces the passage of floating oil through the filter.

Claims (1)

 Installation for cleaning liquids from oils and suspended solids, containing a sewage supply pipe, a housing divided by vertical partitions into sections for rough cleaning with a means for trapping oils and suspended solids, thin-layer separation with a block of inclined plates and collecting purified water, an oil sump communicating with the oil collecting tray , a system for removing sludge, characterized in that it is provided with a post-treatment section after the thin-layer separation section with a filter element consisting of a layer of wood flour having previously undergone heat treatment in an aqueous medium and washed from soluble compounds and bounded from above and below by a fine-mesh stainless steel mesh, the inclined plates of the thin-layer separation unit are corrugated, coated on one side with a paraffin-vaseline mixture, and the installation is equipped with L-shaped guides directed to the oil collecting tray pipes connected to the discharge holes of small diameter, made in the upper part of the longitudinal wall of the housing.