RU2471717C2 - Water treatment apparatus - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention may be used for removal of insoluble admixtures from fluids. Proposed apparatus consists of tank 1, rectangular in plan, equipped with feed and discharge branch pipes 2, 3, sediment collector composed of drive and driven shafts 4 running in bearings. Reel of permeable film is fitted on driven shaft 4. free end 6 of said reel is arranged on surface of permeable web 7 making closed chamber with walls and bottom and secured to driven shaft 8. Permeable film reel, a membrane, is fitted on driven shaft 4. Suction chamber of pump 12 is connected to closed chamber discharge branch pipe 3. In operation, film with deposited slime is reeled on drive shaft 8. In reeling and keeping the reel above water surface, sediment is dehydrated. After dehydration, film reel with sediment is directed to range for solid wastes. In case the tank is equipped with idle shaft 5, driven and idle shafts 4, 5 are located under water level while drive shaft 8 is located above water surface. Note that membrane edge is laid under idle shaft 5 and secured to drive shaft 8.

EFFECT: higher efficiency of treatment, extraction of dehydrated admixtures.

4 cl, 2 dwg, 2 tbl, 2 ex

Description

The invention relates to the field of purification of liquids from insoluble impurities, for example, the purification of natural and waste water.

Known reservoir for water purification by sedimentation, described in [1]. The tank contains a rectangular container in plan, a device for collecting and removing sludge, as well as receiving and distribution trays with nozzles.

The purified water is supplied to the tank through the pipe for supplying water to the receiving tray, and then moves horizontally to the discharge tray and is discharged through the pipe outside the sump. In this case, insoluble impurities in the form of a precipitate whose density is greater than the density of water fall out of the water being purified on the bottom of the tank. Then the sediment deposited on the bottom of the tank is removed from the tank using various devices for collecting and removing sediment, for example, scraper mechanisms.

The disadvantage of this solution is the high humidity of the sludge extracted from the sump and, as a result, the high costs of dewatering it.

The closest solution to the claimed invention is a water treatment plant in the form of a settling tank [2], containing a rectangular container in plan with inlet and outlet pipes located in its upper part. In the lower part of the tank at opposite walls are the leading and driven shafts. At the same time, a roll of a permeable film (membrane) is placed on the driven shaft, the free end of which is located on the bottom of the settling tank and is attached to the drive shaft equipped with a drive with its edge.

In the process, the liquid to be cleaned enters the tank through the inlet pipe and moves horizontally to the outlet pipe. When the liquid moves through the reservoir, insoluble impurities are released from it in the form of a precipitate that falls on a section of a permeable film (membrane), unwound from a roll and laid on the bottom.

The drive shaft is driven into rotation, which is accompanied by the horizontal movement of the permeable film (membrane) along the bottom, while the membrane along with the sediment is wound on the drive shaft.

Due to the fact that when winding a permeable film on the shaft there is a partial dewatering of the sludge, the moisture content of the sludge extracted from the sump is reduced compared with the known methods of sludge removal.

The disadvantage of this solution is the high cost of sludge dewatering and the low liquid purification effect.

The objective of the invention is to reduce the moisture extracted from the treated water sludge while increasing the effect of water treatment.

To solve this problem, it is proposed to additionally equip the capacity of the water treatment plant with a water-permeable partition, which forms a closed cavity with walls and a bottom and serves as a substrate for a water-permeable film (membrane), and connect the outlet pipe to the specified closed cavity. It is proposed to connect the pump to its outlet pipe with its own suction cavity. The tank is additionally equipped with guides in which the bearings of the drive and driven shafts are located, as well as with an intermediate shaft, while the drive shaft is located above the surface of the liquid.

During the operation of the installation, the purified water is supplied to the tank through the pipe for supplying water, and then penetrates through the permeable film and the permeable partition (substrate) into the closed cavity formed by the permeable partition and the walls of the container. From a closed cavity, water enters through a discharge pipe and is pumped out and sent for use, and the sediment accumulates in the pores of the film and on its surface. The film along with the precipitate is wound on a drive shaft in the form of a roll. From the roll, water flows by gravity into the reservoir.

New in the claimed invention is the retrofitting of a device for collecting and removing sludge, which is part of the installation for water purification, as follows:

- a permeable septum, forming a closed cavity with walls and a bottom, to which a discharge pipe is attached;

- a pump connected to the outlet pipe by its suction cavity;

- intermediate shaft;

- guides with bearings of the driven and intermediate shafts placed in them.

Also new is the location of the drive shaft above the surface of the water.

The use of the specified retrofitting of devices for collecting and removing sludge that are part of water treatment plants in order to reduce the cost of sludge dewatering while increasing the effect of water purification has not been identified from the existing level of technology, which allows us to conclude that the claimed invention meets the criterion of “inventive step” ".

Equipping a device with a water-permeable partition for collecting and removing sludge, which is part of the water treatment plant, allows you to remove sludge from the installation with a low water content, and therefore reduce the cost of its further dehydration. At the same time, this solution provides an increase in the effect of water purification. An increase in the degree of sludge dewatering is also facilitated by the placement of the drive shaft above the surface of the water.

The equipment of the water treatment plant with a pump, the suction cavity of which is connected to the outlet pipe, allows for an increase in productivity, and retrofitting it with guides with the bearings of the driven, intermediate and drive shafts placed in them provides the convenience of replacing rolls of a permeable film.

The invention is illustrated in the drawing, where figure 1 shows a longitudinal section, and figure 2 is a plan.

The water treatment plant contains a container 1, rectangular in plan, on the opposite sides of the tank are inlet 2 and outlet 3 pipes. A driven shaft 4 and an intermediate shaft 5 are placed under the water level in the tank. A roll of permeable film is placed on the driven shaft, the free end 6 of which lies on the permeable partition 7, passes under the intermediate shaft and is fixed with its edge on the drive shaft 8. The pores of the permeable partition are usually larger than the pores of the permeable film. The ends of the driven and intermediate shafts have bearings and are placed in the guides 9.

The drive shaft has a drive in the form of a gearbox 10 and an engine 11. The installation includes a pump 12 connected to its outlet pipe.

Installation works as follows. The liquid to be cleaned enters the container 1 through the inlet pipe 2. When the liquid is kept in the tank, insoluble impurities fall onto the area of the permeable film 6. At the same time, under the influence of the height of the water column, the liquid penetrates through the pores of the permeable film 6 and through the pores of the permeable partition 7 into the cavity under the permeable partition. From the cavity under the permeable partition, the water flows through the outlet pipe 3 to consumers by gravity and (or) under the influence of the vacuum created by the pump 12.

Simultaneously with keeping the liquid in the tank, a horizontal movement of the water-permeable film is organized along the surface of the water-permeable partition, which is ensured by rotation of the drive shaft 8 and winding of film 6. The rotation of the drive shaft is carried out in a known manner, for example, using a gearbox 10 and motor 11.

After the film is completely rewound from the driven shaft 4 and wound on the drive shaft 8, the latter can be sent for further dehydration or to the solid waste landfill, and a new roll of permeable film is loaded into the container. Bearings are put on the ends of the driven shaft of the new roll, these bearings are inserted into the guides 9 and the roll is lowered onto the permeable partition 7. Prior to loading, the end of the film is unwound from the roll and fastened to the drive shaft 8 with its edge, after which the intermediate shaft 5 is lowered and then the position is fixed drive shaft. After performing these operations, the area of the permeable film between the driven and intermediate shaft with its entire surface should be in contact with the surface of the partition 7.

Retrofitting the container with a water-permeable partition, which forms a closed cavity with walls and a bottom and serves as a substrate for a water-permeable film, as well as a discharge pipe attached to the specified closed cavity, allows to achieve a higher water treatment effect and lower moisture content of the extracted sediment.

Simultaneously with the achievement of these effects, the consumption of purified water (plant productivity) increases significantly due to an increase in the living cross-sectional area for the water flow.

The increase in the cleaning effect in the proposed installation is explained by the fact that in it there is not only the precipitation of large impurities into the sediment, but also the accumulation of smaller impurities in the pores of the permeable film, which ensures the formation of an additional filter layer. The inclusion of finer impurities in the sediment composition makes it more dense, which is an additional factor contributing to a decrease in the moisture content of the extracted sediment.

Attaching to the pump outlet pipe with its suction cavity allows increasing the flow rate of water passing through the permeable film.

Retrofitting the tank with an intermediate shaft and placing the driven and intermediate shaft below the water level and the drive shaft above the water surface can further reduce the moisture content of the sediment extracted from the water. An additional decrease in sludge moisture occurs due to sludge dehydration due to gravitational removal of water from it. For this reason, the moisture content of the sludge recovered from the installation is less than in known devices.

The retrofitting of the tank with guides, providing the possibility of moving bearings of the driven and intermediate shafts, provides the convenience of replacing contaminated rolls with clean rolls.

The installation device and its operation do not contain elements and operations that may not be feasible with the current level of development of science and technology, which allows us to conclude that the claimed invention meets the criterion of "industrial applicability".

Examples of the invention.

Example 1

To clean rainwater wastewater coming from the control tank and containing suspended solids, the first installation was used, made in accordance with the description of the prototype. It has a container with dimensions in terms of 400 × 3600 mm, the height of the water layer in it is 300 mm. The installation is equipped with a device for collecting sludge in the form of drive and driven shafts, resting their ends on bearings, while a roll of permeable film is put on the driven shaft, the free end of which is placed on the bottom of the tank and attached to the drive shaft with its edge.

As a water-permeable film used non-woven polypropylene material "Spanbond" having a density of 40 g / m ² .

The diameter of the roll of pure nonwoven material is 0.25 m, the length of the roll is 0.3 m, the length of the material in the roll is 150 m.

Purified water was passed through the unit, the flow rate of which was measured using a vane flow meter and a stopwatch. The accuracy of the vane flow meter is 0.15%.

Replacing the contaminated part of the web of the permeable film with a clean one was carried out by manually rotating the drive shaft, and the cloth was replaced over the entire length of the tank after 1 hour.

After a specified period of time, water samples were taken before installation and at the exit of the installation. In the selected samples, the content of suspended solids was determined in accordance with the guidance document [3].

After 8 hours, the contaminated spunbond roll was cut off from the canvas and weighed on a floor scale with an accuracy of 0.1%.

The mass of water in a roll after an eight-hour cleaning cycle was determined by the formula

m _in = m _p -m _h -m _s ,

where m _p is the mass of the roll after the cleaning cycle;

m _h - the mass of a clean roll;

m _with - the mass of trapped impurities in dry matter per cleaning cycle.

To calculate the last value, the formula was used

m _s = (C _out. -C _och. ) · Q · τ,

where C _ref. and _Pts. - the concentration of suspended solids in the source and purified water, respectively;

Q is the flow rate of water supplied for treatment;

τ is the cleaning cycle time (8 hours).

The moisture content of the sediment in the roll was calculated by the formula

w = m _in 100 / (m _in + m _s ).

After performing a series of experiments, the tank was equipped with a permeable partition in accordance with claim 1, while the “Perima” mesh laid on the TENAX biplanar (two-plane) drainage mesh, which is in It is in turn laid on the bottom of the tank. For the removal of purified water from a closed cavity formed by the permeable baffle (mesh) described above and the walls of the tank, a pipe for removing purified water is attached to the bottom.

The previously described experiments were repeated for a retrofitted installation.

The parameters of the installation, made in accordance with the prototype and in accordance with claim 1 of the claims, are presented in table 1.

Table 1 Name of parameters Installation Options According to the prototype According to claim 1 of the claims The consumption of purified water, m ³ / h 4.3 8.0 The concentration of suspended solids, mg / l At the entrance to the installation 400 400 At the exit of the installation 160 one hundred The cleaning effect,% 60 75 Net roll weight, kg 0.46 0.46 The mass of the roll after a cleaning cycle, kg 49.03 83.94 The mass of trapped impurities in dry matter per cleaning cycle, kg 8.26 19,2 The mass of water in a roll, kg 40.31 64.28 Humidity of sediment,% 83 77

From a comparative analysis of the results of the experiments, we can conclude that the additional equipment of the tank with a permeable septum, forming a closed cavity with walls and a bottom and serving as a substrate for a permeable film, as well as a discharge pipe attached to the specified closed cavity, allows to achieve a higher water treatment effect (75% instead 60% of the prototype) and lower moisture content of the extracted sediment (77% instead of 83% of the prototype).

Simultaneously with the achievement of these effects, the consumption of purified water increases significantly (plant productivity).

Example 2

Installation for water purification, made in accordance with claim 1 and described in example 1, was additionally equipped with an intermediate shaft, while the driven and intermediate shafts are located below the water level, and the drive shaft is located above the water surface.

The parameters of the installation, made in accordance with claim 1 and paragraph 3 of the claims are presented below in table 2.

table 2 Name of parameters Installation Options According to claim 1 of the claims According to claim 3 of the claims The consumption of purified water, m / h 8.0 8.0 The concentration of suspended solids, mg / l At the entrance to the installation 400 400 At the exit of the installation one hundred one hundred The cleaning effect,% 75 75 Net roll weight, kg 0.46 0.46 The mass of the roll after a cleaning cycle, kg 83.94 83.94 The mass of trapped impurities in dry matter per cleaning cycle, kg 19,2 19,2 The mass of water in a roll, kg 64.28 64.28 Humidity of sediment,% 77 75

From the analysis of the table it can be seen that the additional equipment of the tank with an intermediate shaft and the placement of the driven and intermediate shaft below the water level, and the drive shaft above the water surface, can further reduce the moisture content of the sediment extracted from water from 77% to 75%.

Information sources

1. Yakovlev S.V., Karelin Y.M., Zhukov A.I., Kolobanov S.K. Sewerage. - M.: Stroyizdat, 1975, p. 238.

2. RF patent No. 2173570, issued October 14, 1992.

3. RD 52.24.468-2005. Guidance document. Suspended matter and total impurity content in water. Methodology for measuring mass concentration by the gravimetric method. - M .: Federal Service for Hydrometeorology and Environmental Monitoring.

Claims (4)

1. Installation for water purification, containing a rectangular container in plan with inlet and outlet pipes, equipped with a device for collecting and removing sludge in the form of drive and driven shafts, resting their ends on bearings, while a roll of a permeable film is put on the driven shaft, free end which is placed on the bottom of the tank and attached to the drive shaft with its edge, characterized in that the tank is additionally equipped with a permeable partition that forms a closed cavity with walls and the bottom and serves under ozhkoy for film-permeable membrane, and a discharge pipe connected to said closed space. 2. Installation according to claim 1, characterized in that the pump is connected to the outlet pipe by its suction cavity. 3. Installation according to claim 1 or 2, characterized in that the tank is additionally equipped with an intermediate shaft, while the driven and intermediate shafts are located below the water level, and the drive shaft is located above the water surface. 4. The installation according to claim 1 or 2, characterized in that the container contains guides that provide the ability to move bearings of the driven and intermediate shafts.

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