SE440642B - PROCEDURE AND PLANT FOR WASTEWATER WASTE CLEANING - Google Patents

Abstract

A method of treating sewage comprises separating solids (3) from the sewage (1), accumulating and averaging the separated sewage (5), and further subjecting averaged sewage (7) to electrochemical treatment so as to produce a foam layer (9), forming in the resulting foam layer (9) air counterflows by means of rarefaction provided by a pump (10) at the solids separation stage such that the flows of air (11) and foam are directed from the peripheral areas of the foam layer (9) towards the central portion thereof and further onto the solids separation stage, while treated liquid (14) is directed towards the area underlying the central portion of the foam layer (9) and subsequently withdrawn therefrom. <IMAGE>

Description

8002019-1 Ship wastewater has a number of characteristics, the most important of which are a very non-uniform supply of wastewater, a high concentration of pollutants, and the occurrence of coarse pollutant fractions in the wastewater, which, as a result of ship-borne sewage systems have a short length, practically do not have time to undergo any physical and chemical changes.

A large number of different procedures and process schemes for wastewater treatment have currently been developed. Under ship conditions, however, a limited number of wastewater treatment procedures were used, due to the fact that the ship-borne wastewater treatment plants must operate under specific, typical ship conditions. The treatment of organic compounds under ship conditions requires compact, efficient and constructively simple devices, which are intended to work under automatic operating conditions, allow frequent shut-off and start and work safely at different salinities in the water, heeling and rolling of the ship.

A known, very simple process for the treatment of ship wastewater involves the atomization of pollutants in the wastewater and chemical decontamination (neutralization) of the wastewater (compare, for example, U.S. Pat. No. 3,472,390).

A device intended for carrying out this known method comprises a disinfection device, a crusher and a pump device for transporting waste water.

However, the ship's wastewater treated by this known device does not meet the applicable international and state requirements and standards.

This is because the wastewater in such a process for its treatment is only decontaminated, but the concentration of suspended solids and the biochemical oxygen consumption do not decrease. These circumstances mean that this known method and the device intended for its implementation have a limited area of use.

Biochemical processes are widely used for the treatment of wastewater with subsequent decontamination thereof (compare, for example, U.S. Pat. No. 3,4 &) 677).

In the process known from this patent, wastewater is treated with activated sludge during forced aeration of the wastewater.

A device intended for carrying out this procedure comprises a sectioned container, a system of pipelines for transporting wastewater and a system for wastewater aeration.

The known method for biochemical treatment of wastewater and the device intended for carrying it out are characterized by a considerable starting time period (approximately two) weeks and a long cleaning time (at least 12-24 hours), which requires an increase in the outer dimensions of the device during treatment. of a large amount of wastewater. The waste water to be treated by the known process must not contain fats and oil products, as these contaminants suppress the vitality of the active sludge.

In addition, when disinfecting the ship-borne sanitary equipment and various ship premises, the active sludge is destroyed by disinfectants entering the device for carrying out this known method, as a result of which the device becomes inoperable.

According to the current requirements, ship wastewater must only be treated within the boundaries of the territorial waters and within limited sea areas, which means that the wastewater must only be treated when the ship is in these areas. To divert contaminants in open areas, the device can be switched off, ie it may happen that the wastewater is not treated. However, because the start-up of the device, which is based on the biochemical process for wastewater treatment, requires a long period of time, this device should not be switched off, which results in a considerable energy and reagent consumption. The continuous operation of the device intended for carrying out the biochemical purification process significantly reduces the service life of the device due to the fact that the operating function of the device is rapidly depleted. In order to be able to successfully carry out the procedure, a uniform so-called pollution load, which ensures the normal vitality of the activated sludge, which is difficult to implement under ship conditions. 8002019-'1 These circumstances result in the biochemical procedure for waste water treatment and the ship-borne device for carrying out this procedure not meeting the requirements to be imposed on the ship's equipment.

Physical and chemical processes for the treatment of wastewater are known (compare, for example, the West German patent specification 2,543,353). The process known for the purification of ship waste water known from this patent is based on the waste water being stored in a storage container, homogenized during the addition of chemicals and atomization of its constituents in solid phase, and fed into a primary sedimentation container, where sludge and precipitates are precipitated. floats to the surface. The wastewater is then purified in an electric reactor tank by electrolysis. The oxygen released by the electrolysis immediately oxidizes the organic substances present in the wastewater, at the same time as the hydrogen released by the electrolysis also forms acids with the inorganic substances present in the wastewater. The acids formed act in such a way that the vitality (life activity) of all kinds of microorganisms is suppressed, after which the purified wastewater, which still contains solids, is introduced into a secondary sedimentation vessel. The sludge from the primary sedimentation tank, the reactor tank and the secondary sedimentation tank is then collected in a sludge collection tank, from where it is fed to a destruction stage, while the purified water from the secondary sedimentation tank is removed overboard.

An apparatus for carrying out this known process comprises a storage container, a container for chemicals, dosing and atomizing devices, a primary sedimentation container, an electric reactor, a secondary sedimentation container and a sludge collection container, which are arranged on a common body. compact rectangular shaped block.

The physical and chemical process and the device for purifying ship wastewater require complicated so-called reagent handling devices, while the device has complicated construction due to the fact that the reagent used in the wastewater treatment must be fed in metered amounts. 8002019-1 The hydrogen gas developed during the operation of the device is not removed, which is why the device is exposed to the risk of explosion. In the process and the device for carrying it out, the sludge is removed from various wastewater treatment steps by precipitating it in advance (the sludge is precipitated in the primary sedimentation tank, the reactor tank and the secondary sedimentation tank). Under ship conditions, ie. in the case of continuous vibrations, rolling and tilting of the vessel, suspended particles precipitate with low efficiency, so that this known device cannot effectively purify wastewater. in this known method, contaminants present in the waste water are atomized before the waste water is purified, which in the subsequent removal of the pollutants from the waste water requires an additional energy consumption and extra time to allow the wastewater to stand, as well as an increased consumption of bills. .

In order for the device for carrying out this procedure for wastewater treatment to be able to operate normally, a considerable stock of reagents must be disposed of on board the ship, which must be stored in a specially equipped room, which also limits extensive use of the physical the chemical process for wastewater treatment and the device for carrying it out.

At present, combined methods for the treatment of ship wastewater are increasingly used, in which the advantages of different process techniques for wastewater treatment are most effectively utilized. For example, physical removal can be combined with degradation of pollutants by electrochemical oxidation. A combined wastewater treatment process is a process known in U.S. Pat. No. 4,009,104 for the treatment of ship wastewater. This known method is almost technically similar to the method of the present invention and has been chosen as a prototype for the same. The process for wastewater treatment known from the said patent is based on the wastewater being treated in several successive steps, in the first step solid phase constituents are separated from the waste water and these constituents are collected. In the subsequent step, the waste water separated in the first step is stored, which is then brought to an average volume and physical and chemical composition, and treated electrochemically, whereupon the contaminants and the purified water are separated, partly by feeding the electrochemically treated liquid into a recirculation container, where the contaminants suspended in the liquid are partly precipitated on the bottom surface, and partly by pumping the liquid partially released from the contaminants in solid phase through filters.

A plant for carrying out this known method for wastewater treatment comprises on the one hand a unit for separating constituents in solid phase from the wastewater, and on the other hand a container connected to the separation unit through a pipeline for storing the wastewater, and bringing its parameters to the average values, on the one hand a unit for electrochemical treatment, which is filled with a liquid, in which electrodes are immersed, and which are connected to the container for storing the waste water and so-called transmission of its parameters through a pressure pipeline, partly a container for purified water, partly filters, partly an energy unit, partly a recirculation tank, partly pumps and partly pipelines with valves arranged in these. This system works by pumping the separated wastewater through the electrochemical treatment unit, the filters and the recirculation tank.

At the plant for carrying out the known method, the electrochemical treatment unit, which consists of an electrolytic cell, is built up in the form of a hollow, cathode-shaped cylindrical casing with anodes arranged therein, which are made of graphite or platinum-coated steel. . The housing of the electrolytic cell is hermetically sealed. An electrically conductive solution and the waste water are allowed to flow through an annular gap between the anode and the cathode.

At the plant's unit for separation of constituents in solid phase, the pollutants are removed in phase phase from the wastewater by passing it to a grid, which can be of the conveyor or centrifugal type.

The process and plant for wastewater treatment are characterized in that the suspended particles, which must be precipitated in the recirculation tank under ship conditions, ie in the case of continuous vibrations, heeling and rolling, are practically not precipitated, whereby they are mainly removed only by felt. clean. These work under exposed conditions, so they are quickly clogged and their work surface must be regenerated frequently or alternatively the filters must be replaced. The inefficient precipitation of suspended particles in the recirculation tank means that these particles are precipitated in the ventilation system, whereby the valves are made inoperable and the functional safety of the plant is reduced, and the wastewater treatment becomes less efficient.

Due to the small surface area of the electrodes, the electrolytic cell of this known plant can only operate at high current density, which leads to the water to be treated rapidly overheating, so that the electrolytic cell must periodically be disconnected from the wastewater source, thereby reducing the electrolytic cell efficiency. If the density of the current flowing between the electrodes is high, the losses of active electric power in the waste liquid to be treated increase significantly, which leads to an increase in the energy consumption per m3 of the waste water to be treated. With such a constructive design of the electrolysis cell, the residence time of the waste water in the space between the electrodes becomes short, which makes the waste water treatment less efficient due to the fact that the effect of the electric field's effect on the pollutants is not utilized sufficiently.

In the treatment of wastewater in the electrolysis cell of said construction, electrochemical flotation is not used to remove the contaminants from the wastewater. The contaminants are either removed by precipitation in the recirculation tank, which, as pointed out above, is not effective under ship conditions due to heeling, rocking and vibrations of the vessel, or is retained by the filters which adversely affects the operation of the plant.

The wastewater treatment during the use of an electrode system in the electrolytic cell is not very efficient and reliable, as the system becomes inoperable when the electrodes wear out or the electrical circuit is broken at the contact point of a current supply means with the active electrode of the electrolytic cell.

The passivation of the active electrodes of the electrolytic cell also results in _. -._ .., ___.,. _ ..._ ._......._..__.._____...._.._._ 8002019-1 a reduction in the degree of purification of the wastewater in the electrochemical treatment unit. Hermetic sealing of the electrolytic cell and the necessity of frequently disconnecting the cell from the plant's common system require a complicated valve system and make the plant's use more complicated. By pumping the waste water in the electrolytic cell in the direction from below and upwards by means of the pump, the already purified liquid is mixed, if the pump's operation is interrupted, for example by overheating the liquid in the electrolytic cell, with the untreated liquid, while flowing downwards into the electrolytic cell. its lower part. The repeated purification of the already purified liquid requires an extra energy consumption for the wastewater. Nor is the wastewater completely purified in the electrolytic cell by the construction described. In order to finally be able to remove all contaminants from the wastewater, this must be pumped through the filters.

The grid in the unit for separating constituents in solid phase from the wastewater is flat and perpendicular to the wastewater stream. With the grille thus designed, the waste water jet falls on it preferably in a local zone, which results in the grille being quickly clogged by the constituents in solid phase and the separation of solid contaminants becoming less efficient. However, the system is not equipped with any special devices for cleaning the grille. In order to limit the fouling of the grille by means of solid phase components, grating-type grids are used in some cases in this plant, which can move forwards and backwards, or of the vibration type. However, in order to make the grid to perform composite movements, extra equipment is required, whereby the wastewater treatment plant has a more complicated construction.

The process and plant for wastewater treatment are thus complicated, provide relatively low efficiency and show low operational safety. In order for the plant to function normally, the condition of the filters and valves must be carefully checked, which considerably makes the purification of vessel wastewater more expensive by means of this known plant. The wastewater treatment also becomes less efficient because the purified and eoo2o19 ~ 1 untreated liquids in this plant circulate through one and the same pipeline system. The plant is also exposed to a high risk of explosion, as it does not remove the hydrogen gas that is developed during wastewater treatment in the electrochemical treatment unit, ie in the electrolysis cell. Nor is this known facility equipped with a ventilation system, which means that unpleasant odors penetrate ship premises. The constructive design of the electrochemical treatment unit and the solid phase pollution separation unit and the reciprocal connection between these units do not ensure efficient and functional wastewater treatment, under ship conditions, ie during continuous vibrations of the ship, and heeling and rolling. .

The main object of the present invention is to provide a method and a plant for wastewater treatment, in which the flow direction of the wastewater in the unit for separation of solid phase constituents and for the pollutants and the purified water obtained in the electrochemical treatment unit are so arranged, respectively, said units are so designed and connected to each other that it is possible to increase the functional safety and efficiency of wastewater treatment under rolling, heeling and vibration conditions for a vessel, whereupon the plant according to the invention is arranged, and at the same time, the construction of the facility is simplified.

This is achieved according to the invention by means of a process for wastewater treatment by treating it in several successive steps, wherein in the first step solid constituents are separated from the liquid and collected, in the second step the liquid separated in the previous step is homogenized with respect to volume equalization and physical / chemical composition, so that the liquid thus homogenized in the third step is subjected to an electrochemical treatment at a flow rate sufficient for the formation of a foam layer on the surface with subsequent separation of contaminants from purified water which characterized in that in the first step during the separation of the solid constituents a negative pressure is generated, which in the third step is maintained during the electrochemical treatment in such a way that under the influence of the negative pressure it is formed in the foam layer against each other. directed air currents, which drive the foam from the edge areas of the foam layer towards it center, and is transferred therefrom in such a manner as to the first step of separating the solid constituents from the liquid, that the foam is mixed with the solid constituents, and that electrochemically purified water is passed to the zone below the center of the foam layer and taken therefrom zone.

This object is further achieved by means of a plant for carrying out the method of wastewater treatment according to the invention which comprises a unit for separating the solid constituents from the wastewater, a container connected to the unit through a pipeline for collecting and homogenizing the wastewater, an electrode unit for a electrochemical treatment, which is provided with means for supplying and discharging waste water and is connected to the container by a pressure pipeline, which is characterized in that a pressurized container is arranged in the unit for separating the solid constituents from waste water. which container is provided with a pipe nozzle, the lower end of which is immersed in the liquid, which is continuously in the separation unit, the container being connected by a pipeline to the unit for the electrochemical treatment, which is provided with a pneumatic device for removing that at the electrochemical the treatment formed the foam.

By forming opposite air flows in the foam layer of the electrochemical treatment unit, which feed the foam from the peripheral portions of the foam layer to its center portion, and by introducing the purified water into a zone below the center portion of the foam layer, the foam can be collected and the purified liquid in the part of the electrochemical treatment unit, where they can move as short a height as possible and where their volume practically does not change, when the wastewater treatment plant is inclined at a considerable angle in the event of rolling and tilting of it. ships, on which the facility is located. This circumstance promotes the removal of the foam and the clean water from the electrochemical treatment unit in good time and safely.

The low pressure generated at the step of separating solids (in the solid phase separation unit from the wastewater) and transferred to the electrochemical treatment of the wastewater at the step of electrochemical treatment makes it possible to simultaneously form opposing air flows in the upper part of the electrochemical treatment unit and transfer the foam from this to the unit for separating solids from the wastewater, which makes the wastewater treatment and the construction of the wastewater treatment plant considerably easier.

By the electrochemical treatment taking place at the flow rate of the wastewater brought to the mean parameters, which is sufficient for a surface foam layer to be able to form in the electrochemical treatment unit, electrochemical flotation can be used to remove the contaminants to the surface of the liquid. to be treated.

By mixing the foam with the solid constituents, which in the first stage are separated from the waste water in the solid constituent separation unit, the solid constituents and the impurities formed during the electrochemical treatment can be removed from a single zone. , which significantly simplifies the process scheme for wastewater treatment and the design of the plant for carrying out the wastewater treatment process.

By connecting the units of the plant, ie the unit for separating solids from the wastewater and the unit for electrochemical treatment, as well as the container for storing the wastewater and bringing its parameters to the respective average values, the number of valves in the plant can be brought to a minimum, which considerably simplifies the facility's constructive design and use and increases the facility's functional reliability.

This interconnection between the units of the plant further makes it possible to purify wastewater without mixing the streams of pure and untreated liquid with each other and without this liquid being allowed to flow through one and the same pipeline system, which makes re- ... R-_ 8002019-1 12 even more efficiently and the efficiency of the plant even higher. In the treatment of the wastewater in the electrochemical treatment unit, electrochemical flotation is used to remove the contaminants from the wastewater, which through the rational interconnection between the electrochemical treatment unit and the unit for separating solids from wastewater, ie takes place in many ways. that the suspended impurities together with the foam formed in the electrochemical treatment unit are transported through the pipeline to the solid component separation unit, from which they are then removed, while removing the hydrogen gas emitted in the electrochemical treatment unit, together with the plant's ventilation is provided.

Since the container arranged in the unit for separating solids from wastewater is provided with a pipe socket, the lower end of which is immersed in the liquid which is continuously in the unit for separating solids and enters this unit. during the separation of said constituents and together the impurities isolated during the electrochemical treatment resulted in the foam being removed and extinguished effectively, and the contaminants separated in the electrochemical treatment unit and in the solid component separation unit are mixed with each other.

The wastewater treatment plant thus has a number of constructive and operational features, which make it possible to successfully and with high operating power use the wastewater treatment plant under ship conditions, ie in case of continuous vibrations and heeling and rolling of the vessel.

According to an embodiment of the method according to the invention for wastewater treatment, the solid constituents are suitably separated, before the foam is mixed with them, by filtering the wastewater through a conical filter surface through the wastewater being directed towards its surface with subsequent removal of the the filter surface accumulated the solid constituents by centrifugal force and by acting on these constituents by means of a medium which contributes to reducing the adhesion (adhesion force) of the contaminants to the filter surface, and under pressure on the inside of the filter surface, to which outside the wastewater is supplied.

The filtration of the wastewater through the conical filter surface while supplying the wastewater stream to the tip of the filter surface contributes to an optimal wastewater distribution over the filter surface, which leads to the solids being separated very effectively from the wastewater and the filter surface being contaminated. towards the base surface of the cone, which in the future promotes a more efficient cleaning of the filter surface by means of the centrifugal forces, which also increase in the direction of the base of the conical filter surface.

By acting on the contaminants collected at the filter surface by means of the medium, which helps to reduce the adhesive force of the contaminants at the filter surface and which is fed under pressure to the inside of the filter surface opposite the side where the wastewater is supplied, the filter surface is better cleaned the impurities precipitated on the filter surface in this case are loosened, melted and dissolved, and the filter surface is flushed with the flow of the adhesive-reducing medium, which is directed towards the wastewater stream. By supplying the medium under pressure, the contaminants cannot end up on the inside of the filter surface, which prevents the contaminants from the filter surface from entering the liquid to be purified.

According to one embodiment of the method, it is suitable that the medium which reduces the adhesive force of the contaminants at the filter surface is applied after 50-60% of the filter surface has become clogged by the contaminants.

In such an implementation of the process, the waste water can not enter the collected solid constituents, and the filtration becomes more efficient because the flow resistance of the filter surface is optimal.

In yet another embodiment of the process, the medium, which is intended to reduce the adhesive force of the contaminants at the filter surface, consists of hot water.

The hot water, which is supplied under pressure to the inside of the filter surface, softens grease deposits, which deposits stick to fiber contaminants and thereby form so-called conglomerates, which are subsequently easily removed from the filter surface by centrifugal force. In the case of hot water supply, the fiber contaminants lying at the filter surface are also loosened, which also makes the cleaning of the filter surface more efficient by means of centrifugal force.

According to a further embodiment of the method according to the invention, suitably said adhesion-reducing medium consists of a mixture of steam and water, which helps to reduce both the water content of solid constituents to be removed from the filter surface and the amount of water which enters in the solids, when collected.

In yet another embodiment of the process, said medium suitably consists of a mixture of water and detergent, for example surfactants.

This helps to more effectively reduce the adhesion of the grease deposit at the filter surface and at the same time reduce the adhesion of the fiber contaminants, thereby further reducing the amount of water that must be used to clean the filter surface. According to another embodiment of the process, the adhesive reducing medium is vapor. , which makes it possible to reduce the water content of the solids to be removed from the filter surface and the amount of water that ends up in the solids when they are collected.

In a further embodiment of the process, the medium which reduces the adhesive force of the contaminants at the filter surface is suitably composed of hot air, which eliminates the increase of the water content in the solid constituents which precipitates on the filter surface, and contributes to to some extent, re-dry these constituents, which facilitate further treatment of the contaminants to be removed from the filter surface.

According to an embodiment of the plant according to the invention for wastewater treatment, it is suitable that the electrochemical treatment unit is built in the form of a sectioned container with a tube arranged vertically in its center part for receiving the purified (clean) liquid, which is hydraulically connected to the means for discharging the liquid and having the section of the container in which the waste water is finally decontaminated, the upper end of the pipe suitably projecting above the liquid level in the container.

By sectioning the container of the electrochemical treatment unit, it is possible by successive transfer of the liquid to be purified from one section to the other to better and more efficiently clean and decontaminate the liquid and reduce flow shocks during the tilting and rocking of the plant to a minimum. .

By arranging the pipe for receiving clean liquid in the center part of the container and only connected to the section where the wastewater is finally decontaminated, under ship conditions pure and impure liquid is mixed with each other, since it lies in the center part of the container. the zone is characterized by a constant volume of liquid and by the fact that it moves as short a vertical distance as possible when the ship is heeling and rolling.

This circumstance results in the purification quality of the liquid to be treated in the electrochemical treatment unit becoming stable and in the formation of liquid splashes in the container being eliminated and the electrodes not being able to be exposed.

Because the upper end of the tube for receiving pure liquid protrudes above the liquid level in the container, the impure liquid and the foam can not be introduced into the container for clean water and further into the water to be removed overboard.

According to a further embodiment of the plant according to the invention, the pneumatic device for removing the foam is provided with an air line, which is arranged along the upper edge of the electrochemical treatment unit and is provided with air outlet holes, which are received in the air surface facing the interior of the electrochemical treatment unit. , and with air intake holes, and on the one hand a foam receiving means, which is arranged in the center part of the electrochemical treatment unit above the upper limit of the liquid level in said unit and connected to a fan, which is intended to generate negative pressure in the container, which is arranged in the unit for separating solids from the wastewater, and in the foam receiving crane and in a space delimited by the liquid surface of the electrochemical treatment unit, its lid and the air line.

The air line arranged along the upper edge of the electrochemical treatment unit with the air outlet holes and the air suction holes makes it possible to rationally distribute air over the entire periphery of the upper edge of the electrochemical treatment unit, the air flows driving the foam from the electrochemical treatment unit peripheral parts to its center the foam layer moves as short a distance as possible. At the considerable angles of inclination of the plant resulting from rolling, vibration or heeling of the vessel on which the plant is arranged, the volume of the water to be purified and of the foam in the central part of the electrochemical treatment unit practically does not change, which promotes the foam to be removed in good time and safely to a foam collection container.

The foam receiving means arranged in the center part of the container makes it possible to collect the foam in the electrochemical treatment zone, where the liquid and the foam move vertically as little as possible, which also facilitates removal of the foam from the electrochemical treatment unit.

Because the foam receiving means is arranged above the upper limit of the liquid level in the electrochemical treatment unit, the liquid to be purified cannot be introduced into the foam receiving means.

Because the foam receiving means is connected to the fan, which generates low pressure partly in the container, which is arranged in the upper part of the unit for separating constituents in solid phase from the waste water, partly in the foam receiving means itself and partly in the space delimited by the liquid surface in the electrochemical treatment unit, its lid and the air duct, the air to be sucked in through the suction holes of the air duct can be discharged (distributed) at the same time through the air outlet holes, transported the foam from the electrochemical treatment unit to the solid separation unit and ventilated only device, ie. a fan, whereby the construction of the plant and the so-called process flow connections are made simpler. In another embodiment of the plant according to the invention, it is suitable that in the space, which is delimited by the outside of the foam receiving means and the inside of the air duct, vertical partitions are arranged for dividing the space into sections.

Such a constructive design makes it possible to prevent the air flows from crossing each other, which leads to a more rational flow of the air flows and consequently to a more efficient evaporation of the foam in the electrochemical treatment unit.

According to a further embodiment of the plant, it is suitable that the vertical partitions are arranged so that their lower edges are immersed in the liquid in the electrochemical treatment unit and their upper edge at least reaches the upper edge of the air duct.

The partitions so designed prevent the air flows from flowing above or below the partitions, which results in an optimal flow of the air flows and consequently facilitates the foam drift in the desired direction. in yet another embodiment of the plant the unit for separating solids comprises an inlet pipe socket for the waste water, under whose outlet hole a shaft is arranged a conical filter, the side surface of which is folded towards the tip, a screen being arranged on said shaft, while below the base surface of the conical filter a receiving funnel is arranged for the separated waste water, provided with an outlet pipe spout, a so-called skirt-shaped member coaxially with the shaft being arranged, which has the shape of a cylinder of elastic material and separated from the base surface of the conical filter by a distance exceeding the maximum particle size of the solid pollutants to be separated. The conical filter so designed makes it possible to evenly distribute the currents of the liquid to be purified over the filter surface and to prevent the solid contaminants from accumulating in the vicinity of the center of rotation, where centrifugal forces generated by rotation of the filter the conical filter, are low, so that when cleaning the filter surface it is possible to reduce the speed of the conical filter shaft, which is of particular importance, since the filter must operate under ship conditions.

The uniform distribution of the wastewater streams over the surface of the conical filter contributes to a more efficient purification of the filter surface of the filter and of the liquid to be purified.

Since the outlet hole of the inlet nozzle is formed above the tip of the conical filter, the liquid to be purified can be uniformly distributed over the surface of the conical filter, which promotes that the filter surface becomes contaminated uniformly, whereby the contaminated liquid and the filter surface can be cleaned more efficiently. .

Because the side surface of the conical filter is extended towards the tip of the filter, the waste water which drains along the outside of the conical filter cannot enter the container for collecting the solid constituents, which in other words means that the separated solid contaminants with the lowest possible water content and can purify the contaminated liquid more efficiently. The side surface thus designed promotes the accumulation of the solid constituents in the vicinity of the base surface of the conical filter, which makes the cleaning of the filter surface of the conical filter more efficient in that the centrifugal forces acting on the contaminants closer to the base surface of the conical filter are higher. than those operating near the tip of the filter.

By arranging the skirt-shaped member of elastic material coaxially with the shaft supporting the conical filter, the contaminants are prevented from sticking to the walls of the filter housing and the walls of the filter are eroded. The arrangement of this skirt-shaped member prevents however, not that the solid contaminants penetrate into the lower part of the solid component separation unit but prevent (by the skirt-shaped member being elastic) that the contaminants re-end up on the filter surface.

In yet another embodiment of the plant according to the invention, the side surface of the filter is suitably folded at an obtuse angle.

This prevents blind pockets from forming in the conical filter, which makes the cleaning of the filter surface of the filter and the contaminated liquid more efficient.

According to a further embodiment of the plant, it is suitable that the skirt-shaped member is arranged such that its lower edge extends at least up to the base level of the conical filter.

This helps the walls of the filter housing to be better protected against the solid contaminants sticking to the filter housing, thereby avoiding the erosion of the walls of the housing.

In yet another embodiment of the plant, it is suitable that in the receiving funnel for clean waste water, along its upper edge facing the base surface of the conical filter, an annular tube is arranged against holes which are accommodated in the tube surface facing the conical filter. inside, which tube through a pressure regulator is connected to a source of a medium which is intended to reduce the adhesive force (adhesion force) of the contaminants at the filter surface of the filter.

This makes it possible to supply the pressure-reduced medium in liquid or gas phase to the inside of the filter surface under pressure, which medium, by influencing the deposits at the filter surface, reduces the adhesion of the deposits at the filter surface, whereby the filter surface can be better cleaned and used more efficiently. centrifugal forces, which are generated by the rotational movement of the filter, when the filter runs.

The holes in the tube, through which the medium is supplied to the inside of the filter, are arranged such that jets of the adhesion-reducing medium flowing out of the holes bridge the entire inside of the filter surface of the conical filter.

By supplying the medium, which is intended to reduce the adhesion force of the impurities at the filter surface of the filter, under pressure by means of the pressure regulator, the impurities end up on the inside of the filter surface, so that the impurities from the filter surface cannot be introduced into the liquid to be purified.

In yet another embodiment of the plant according to the invention, it is suitable that the holes in the ring-forming tube widen in the direction of the outer wall (outside) of the tube.

This enables the most rational utilization kinetic energy 8002019-1 in the effluent medium, which is intended to reduce the adhesion force of the contaminants at the filter surface.

In a further embodiment of the plant, it is suitable that the holes in the annular pipe are provided with conical diverging nozzles.

This makes it possible, by an insignificant complication of the construction, to make even more rational use of the kinetic energy of the medium flowing out of the nozzles, which is intended to reduce the adhesive force of the contaminants at the filter surface. The invention is described in more detail below with reference to the accompanying drawings. Fig. 1 shows a process diagram for carrying out the method according to the invention for wastewater treatment, Fig. 2 shows a principle diagram of the electrochemical treatment unit, which diagram shows the position of the liquid level and the foam layer at considerable inclination angles for this unit, Fig. 3 shows a curve , which represents the relationship between the flow resistance of the filter surface and the degree of clogging of the filter surface, Fig. 4 shows a principle diagram of the plant for carrying out the method according to the invention for wastewater treatment, Fig. 5 shows a top view of the plant according to Fig. 4, fig. Fig. 6 shows a plan view of the plant according to Fig. 4, fi Fig. 7 shows, on an enlarged scale, a section through the electrochemical treatment unit shown in Figs. 4-6, Fig. 8 shows a top view of the unit shown in Fig. 7, Fig. 9 shows a section along line IX-IX in Fig. 7, Fig. 10 shows, on an enlarged scale, a section through another embodiment of the electrochemical treatment unit shown in Figs. 4-6, Fig. 11 shows a section along line XI-XI in Figs. Fig. 12 shows, on an enlarged scale, a section through another embodiment of the electrochemical treatment unit shown in Figs. 4-6, Fig. 13 shows, on an enlarged scale, a section along line XIII-XIII in Figs. Fig. 14 shows, on an enlarged scale, a perspective view of the overhead line shown in Figs. 4-6 (in the form of a hexahedron), Fig. 15 shows the overhead line shown in Fig. 14 (with circular shape) Fig. 16 shows the air line shown in Fig. 14 with the cylindrical electrochemical treatment unit, Fig. 17 shows, on an enlarged scale, a section through the unit shown in Figs. 4-6 for separation. Fig. 18 shows, on an enlarged scale, a top view of the annular pipe shown in Fig. 17, Fig. 19 shows a solid component of the waste water with the conical filter arranged on the unit. section along line XIX-XIX in Fig. 18, Fig. 20 shows a portion D shown in Fig. 19 and Fig. 21 shows a curve representing the working process of the plant according to the invention shown in Figs. 4-6.

The process for wastewater treatment is clarified by means of the process diagram shown in Fig. 1. Contaminated liquid (wastewater) is treated in several successive steps, the wastewater 1 being filtered through a conical filter surface 2 in the first step.

Solid constituents 3 are then separated from the liquid constituent of the waste water 1, stored in the lower part of a unit 4 for separating the solid constituents 3 from the waste water 1 and then fed to a destruction or utilization step. The separated waste water 5 is stored and its volume and physical and chemical composition are brought to an average volume and an average composition, respectively, in a container 6. The waste water 7 brought to the average volume and composition is treated electrochemically in an electrochemical treatment unit 8. At the same time the electrochemical treatment is carried out, coagulates colloid particles, whereby the coagulated colloid particles are exposed to flotation of hydrogen bubbles, which are formed by electrolysis and decontamination of the waste water.

The wastewater can, depending on its chloride content, be electrochemically decontaminated (neutralized) by means of chlorine (at high chloride content), hydrogen peroxide and ozone (at low chloride content). The amount of chlorine, hydrogen superoxide and ozone formed during the electrolysis of the waste water with different chloride contents may vary, while the total amount of decontaminants in the waste water to be treated is kept constant. g / The electrochemical treatment is carried out at the flow rate of the effluent 7 brought to the average volume and composition, which is sufficient for a foam layer 9 to be formed. Opposite air flows 11 are formed in the foam layer 9, the unit 4 for separating the solid constituents 3 from the waste water 1 and consequently in the electrochemical treatment unit 8 connected to the unit 4 under the influence of a low generated by a fan 8002019-1 22 10. pressure, the foam being driven from the peripheral portions of the foam layer 9 in the direction of the center portion of the foam layer 9, indicated in Fig. 1 by a dashed rectangle, from which impurities 12 suspended in the foam are transferred to the separation unit 4 under the influence of the same low pressure. is then mixed with the solid constituents 3 separated from the unit 4, the mixture 13 from the separation unit 4 being fed to a destruction or utilization step.

A purified (clean) water 14 is introduced into a zone located below the center portion 9 of the foam layer 9, from where it is removed to a collection container with subsequent utilization or removal of the pure water overboard.

In the electrochemical treatment, in the foam layer 9, the opposite air flows 11 are formed, which feed the foam from the peripheral portions of the foam layer 9 to its center portion and expel the pure water 14 to the zone below the center portion of the layer 9. possible to collect the foam and the clean water 14 in the zone with the least possible vertical distance of movement and with practically constant volume at considerable angles of inclination of the electrochemical treatment unit, which result from heeling and rolling of the vessel, on which this unit is arranged. This is clarified by the principle diagram shown in Fig. 2 of the electrochemical treatment unit 8, which principle diagram shows the level of the liquid and the foam layer 9, when the unit 8 tilts considerably.

As can be seen from the principle diagram, the phase boundary between the foam layer 9 and the water present in the unit 8 can run at considerable angles of inclination of the unit 8, for example along the lines A or B.

The water and foam layer level remains only constant in the center portion of the foam layer 9 and in the adjacent water volume, ie. at a point C, so that the volume of foam and water near the point C remains constant. It is thus suitable to drive the foam and the clean water to the zone located near the center portion of the foam layer 9, when using the method proposed according to the invention for wastewater treatment by means of plants intended to work on board ships, ie. in case of continuous vibrations, heeling and rolling of the ship. 8002019-1 23 The method is further characterized in that the waste water 1 (Fig. 1) is supplied to the tip of the conical filter surface 2, which contributes to the optimal distribution of the waste water 1 over the filter surface 2. This results in a very efficient separation of the solid constituents 3 from the waste water 1 and in that the filter surface 2 becomes uniformly contaminated with the degree of contamination gradually increasing in the direction of the base of the conical filter surface 2. The solid constituents 3 accumulated at the filter surface 2 are removed from the surface 2 partly under the influence of the centrifugal forces generated by rotation of the conical filter surface 2, and partly by exposing these constituents to the influence of the medium 15, which is intended to reduce at the adhesive force of the solid constituents 3 at the filter surface 2 and which under pressure is applied to the inside of the surface 2, which is opposite the side to which the waste water 1 is fed.

By causing the medium 15 to act on the solid constituents 3 accumulated at the filter surface 2, the surface 2 is better cleaned, since the impurities deposited on the filter surface are loosened, melted and dissolved.

Because the medium 15 is supplied under pressure, the contaminants cannot end up on the inside of the filter surface 2, which in turn prevents the contaminants from the filter surface 2 from being introduced into the separated waste water 5.

The pressure under which the medium 15 must be supplied can vary widely and depends on a number of factors, the most important of which are the type of the adhesion-reducing medium 15, which may be in the liquid or gas phase or may be a mixture of liquid. with gas, temperature of the medium, type of deposits on the filter surface 2, etc.

It is most suitable that the pressure for the medium 15 in the liquid and gas phase and for the medium 15 in the form of a liquid-gas mixture is 1-2 atoms (105 N / m 2 to 2,105 N / m 2), 3-5 atoms 13.105 N / mz to 5.105 N / mz) and 2.5-3 atoms (2.2-1o5 N / mz to 3.105 N / mz), respectively.

It should be noted that the supply of the medium 15 has a favorable effect on the effect of the centrifugal forces, which are a main means of removing the contaminants from the filter surface 2. The contaminants whose adhesive force to the filter surface is reduced are easily removed from the filter surface by the centrifugal forces. , whereby these can be caused to act on the contaminants either at the same time as the adhesive reducing medium 15 is applied or immediately after its application.

The medium 15 is applied after 50-60% of the filter surface 2 has been clogged by the impurities, which percentage is determined by the increase in the flow resistance of the filter surface 2, which results from the filter surface 2 being covered by impurities with large particle size, for example paper, cotton wool and the like. . In this case, the flow resistance increases exponentially depending on the degree of coverage of the filter surface 2, as can be seen from the exponential curve shown in Fig. 3.

In Fig. 3, along the ordinate, the flow resistance of the contaminated (clogged) filter surface 2 is plotted without taking into account the flow resistance of the clean filter surface 2. Along the abscissa, the degree of contamination of the filter surface 2 is expressed as a percentage of the total area 2. From the curve shown in Fig. 3 it appears that the flow resistance of the filter surface 2 is within the optimal limits when 50-60% of the filter surface 2 is clogged. If the surface 2 is clogged to a greater degree, the flow resistance suddenly increases, whereby a larger amount of liquid component of the waste water 1 to be purified is introduced into the unit 4 (Fig. 1) for separation of solid constituents. If the degree of clogging of the filter surface 2 is less 50-60%, the supply of the adhesion-reducing medium 15 entails a high consumption of the medium as well as a less efficient purification due to time consumption, which results from the filter surface 2 having to be regenerated frequently.

The medium 15, which is intended to reduce the adhesive force for contaminants at the filter surface 2, may consist of different substances or their mixtures in liquid or gas phase. The medium 15 can preferably consist of hot water, a mixture of steam with water, a mixture of water with detergent, for example surfactants, steam / hot air, etc.

Concrete examples are described below of the cleaning of the filter surface 2 from the solid constituents 3 deposited thereon and of the effect of the adhesion-reducing medium 15 of varying kinds on the inside of the filter surface 2.

Example 1. An example of the implementation of the procedure for wastewater treatment is the cleaning of the filter surface 2 contaminated with grease and fiber deposits by means of centrifugal forces and the action of hot water on the inside of the surface 2.

The filter surface 2 may be permeated by 300 liters of waste water 1 with a temperature of 20 ° C, which on average contains 650 mg of pollutants per liter, which pollutants consist of fat pollutants and fiber pollutants, which occur at levels of 0.1 g and 0.05 g per liter. 27 g of fat contaminants and 12 g of fiber contaminants adhere to the filter surface 2. The filter surface 2 is regenerated, at the same time as it rotates at a speed of 1000 rpm and 60 liters of water with a temperature of 50 ° C at a pressure of 1 atm (105 N / m2) are fed to the inside of the surface 2.

It has been found that the fat contaminants, if the filter surface 2 is washed with hot water at a temperature of 50 ° C, together with the fiber contaminants form so-called conglomerates, which are easily removed under the influence of centrifugal forces. 11 experiments have been performed with washing of the filter surface 2 by means of hot water and 11 experiments with washing of the surface 2 only by centrifugal purification. The experimental results are reported in the table. The table shows that the purification of the filter surface 2 using a combined effect of centrifugal forces and hot water on contaminants becomes more efficient by the increase in the efficiency of the centrifugal process for cleaning the filter surface 2, which results from the adhesion force (adhesion force) of the contaminants to the filter surface 2 is reduced by the effect of hot water on the pollutants. hot water with a temperature of not more than 50 ° C is suitably used for cleaning the filter surface on board large passenger boats, where a considerable supply of water with said temperature is available to the passengers and crew.

Example 2. Another example of carrying out the process is the purification of the filter surface 2 by means of centrifugal forces and the influence of hot water on its inside, the hot water temperature exceeding the melting point of the grease precipitates on the filter surface 2.

The filter surface may be permeated by 300 liters of waste water with a temperature of 20 ° C, which on average contains 650 mg of pollutants per liter, which consist of fat and fiber pollutants, which on average occur in concentrations of 0.1 g and 0, respectively. 05 g per liter. vid fil- HH _ HH 8002019-1 TOHH _ 36. wa H m øHamuH NHá æHá m HN OH m | o. fi. w NHO zHO N. NN m m | oH »HHC m ~ .o NH @H w n OH w Hwssox æO.o æno m NH H | | mnom mm: HswHonæmuuwu m | oH.m> m hmmm ummøsm »Hm .umm mH.o: .o: H mm w H OH -H> wa: w = HH @ nmH» xw »» @ H H_o mO.om HH m 1 m: m.Hnmhmuuw fl mE.Hm © wE _ n | oH.m | mw: HcwmH wwë m: H: upm> B mo Ho oH mH m TQH w H5 wa H ä H. mm .muuxm fi .. H n | oH N »HHw: wH> hm sax w O m Q m om .m n | oH nmw: Hcwnonnmpumm H m.o mH Nm H w w H m w. ww nmwn fi c nmwcwc HmmnH: nmw: H: Hmw: H: mmw: Hc | mnonmmnwpHm nmmonmmpumm | mnoawHnwnHm uwnomwmpumm | mnonwmmmnH nmnommmupmm cwp »æ> Enm>» nHmømHHm> HHmm> wu | pcøo »wHmømE m: Hnwn mmwu mm» umHwnms m: Hsmm mmmu nmpmw: mm: m @ anm »HHm cH> m @ mcEmHnm> x: mp> mw» HHm øH> mumcEmHnmuwm mcmmwcHcwmspm Hmwmmm. mv> m @xH> Eom .mmw: H: mnonmw mv> m pxH>: mu> mopHHw UH> mn> m @xH> xnwnmm. .: mapm> snm> uwë: mp> mw »HHw> mw: Hcpum> u umë soHpmcHnEox H Hm» mwmxHmw: m x fl nusmo umHmvwE: oo uw »HmnxHmwsuHhuswo pmHwumE nmmcHcwnoam Hmwmhmmhm: mm HHQQMB 27 8002019-1 surface 2 sticks 26 g fat impurities and 13 g fiber impurities.

The filter surface 2 is regenerated at the same time as it rotates at a speed of 1000 rpm and hot water with a temperature of 70 ° C and under a pressure of 1 atm (105 N / m2) is fed to the inside of the surface 2, which temperature exceeds the melting point of the grease deposits on the filter surface 2. In order to achieve the same degree of purification for the filter surface 2 as in Example 1, a considerably lower amount (total 36 liters) of hot water with a temperature of 70 ° C is required, ie with 24 liters less than in use of water with a temperature of 5000.

The use of hot water with a temperature of 70 ° C for cleaning the filter surface thus makes it possible to save washing hot water. This embodiment of the method is suitably used on board small boats, where the supply of hot water is limited.

Example 3 as another example of the implementation of the process is considered here the purification of the filter surface contaminated by grease and fiber contaminants by means of centrifugal forces and the action of a steam-water mixture on the inside of the filter surface.

The filter surface 2 is permeated by 200 liters of waste water with a temperature of 20 ° C, which on average contains 650 mg of impurities per liter, which consist of fat and fiber impurities, which on average occur in concentrations of 0.1 g and 0, respectively. 05 g per liter.

24 g of fat contaminants and 12 g of fiber contaminants adhere to the filter surface 2. The filter surface 2 is regenerated at the same time as it rotates at a speed of 1000 rpm and a steam-water mixture under a pressure of 2.5 atm (2, p.185 N / mz) is supplied to the inside of the surface z.

At a steam temperature of 127 ° C, a mutual weight mixing ratio between steam and water is equal to 2: 0.8 (ie 2 kg of steam per 0.8 kg of water). In this case, 21 liters of water are consumed for washing.

This embodiment of the process is suitably used on board vessels with a centralized steam supply system.

Example 4. Another example of carrying out the process is the cleaning of the filter surface contaminated by grease and fiber deposits by centrifugal forces and the action of a steam-water mixture on its inside. The filter surface 2 may be permeated by the same amount of waste water as in Example 3 and with the same average levels of impurities. 28 g of fat contaminants and 10 g of fiber contaminants adhere to the filter surface.

The filter surface 2 is regenerated at the same time as it rotates at 1000 rpm and a meadow-water mixture under a pressure of 3 atm (3J05 Nmå) is added to the inside of the filter surface. The steam temperature is 134 ° C. Per 0.0 kg of water, 1 kg of steam was used. In this case, 16 liters of water are consumed for washing.

If the vapor temperature and the vapor pressure increase, the water consumption for regeneration of the filter surface 2 decreases, which reduces the water content of solid constituents 3, which at the filter surface 2 are to be separated from the waste water 1.

Example 5. Another example of carrying out the process is considered here the purification of the filter surface contaminated by grease and fiber deposits by means of centrifugal forces and the action of hot water with the addition of detergent on the inside of the filter surface.

The filter surface is permeated by 300 liters of waste water with a temperature of 20 ° C, which on average contains 650 mg of pollutants per liter, which pollutants consist of fat and fiber pollutants, which occur on average at levels of 0.1 and 0.05 g per liter. 27 g of fat contaminants adhere to the filter surface 2 and 12 g of the fiber contaminant. The filter surface 2 is regenerated by rotating at 1000 rpm and hot water at a temperature of 50 ° C and under a temperature of 1 atm (105 N / mg) is added to the inside of the filter surface 2. , the hot water being added with detergent consisting of disodium salt of monoalkylsulphosuccinic acid in a concentration of 0.5%.

In order to be able to achieve the same degree of purification for the surface 2 as in Example 1, a considerably smaller amount of hot water is required (a total of 20 liters), ie with 40 liters less than when using only hot water with a temperature of 50 ° C.

This embodiment of the method is suitably used for small boats with a limited supply of hot water, where the waste water which has been allowed to flow through the filter surface must be subjected to further purification and decontamination.

The detergent can also consist of other surfactants. . 80020194 29 pexample 6. Another example of carrying out a process is the cleaning of the filter surface contaminated by grease and fiber deposits by means of centrifugal forces and the effect of hot water with detergent additive. The wastewater is treated and the filter surface 2 is purified under the same conditions as in Example 4, except that the water temperature in this case is 70 ° C.

To achieve the same degree of purification for the filter surface 2 as in Example 4, a considerably lower amount of hot water (a total of 14 liters) is required.

In the case of a limited water supply, it is therefore appropriate to increase the water temperature when using this embodiment of the process.

Example 7. Another example of carrying out a process is considered here the cleaning of the filter surface contaminated by grease and fiber deposits by means of centrifugal forces and the action of steam on the inside of the filter surface.

The filter surface 2 may be permeated by 300 liters of waste water with a temperature of 20 ° C, which on average contains 650 mg of pollutants per liter, which consist of fat and fiber pollutants, which on average occur in average levels of 0.1 and 0.05 respectively. g / liter. 24 g of fat contaminants and 13 g of fiber contaminants adhere to the filter surface 2. The filter surface is regenerated by rotating it at 1000 rpm and steaming at a temperature of T20 ° C and a pressure of 2 atm is applied to the inside of the filter surface.

In order to achieve the same degree of purification for the filter surface 2 as in the examples described above, a total of 2.8 liters of water is introduced into the contaminants removed from the filter surface by steam condensation.

With continued treatment of the contaminants, for example with heat treatment of these, by reducing the water content of the contaminants by using steam for cleaning the filter surface, the fuel consumption for the heat treatment can be significantly reduced.

This embodiment of the method is suitably used when the vessels in question are provided with steam generating devices. the increase in the steam temperature and the pressure at which the steam is supplied to the filter surface 2 make the purification thereof more efficient, but the choice of the steam temperature and the steam pressure must be determined by technical considerations and the type of deposits at the filter surface.

Example 8. Another example of carrying out the process is considered here the cleaning of the filter surface contaminated by grease and fiber deposits by means of centrifugal forces and the action of hot air on its inside.

The filter surface 2 is permeated by 300 liters of waste water with a temperature of 20 ° C, which on average contains 650 mg of pollutants per liter, which consist of fat and fiber pollutants, which occur in average levels of 0.1 and 0.05 g per liter, respectively. liter. 24 g of grease contaminants and T3 g of fiber contaminants adhere to the filter surface 2. The filter surface is regenerated by rotating it at 1000 rpm and hot air at a temperature of 250 ° C and a pressure of 2 atm (2,105 N / m2) is applied to the filter surface. inside.

To achieve the same degree of purification for the filter surface 2 as in the examples described above, the water content of the impurities removed from the surface 2 is reduced by 20% (the initial water content of the impurities is 92-98%).

With continued treatment of the pollutants, for example during heat treatment of these, by post-drying the pollutants when removing them from the filter surface 2, the fuel consumption for the heat treatment can be significantly reduced.

This embodiment of the process is suitably used when a solid combustion furnace is located in the immediate vicinity of the plant for carrying out this wastewater treatment process, which considerably simplifies the transport of these constituents to the furnace, and when there is a board on board the vessel. source of hot gas, for example on board oil tank steamers, where a generator for generating inert gases is arranged.

The plant for carrying out the above-described method for wastewater treatment comprises on the one hand a unit 4 (Fig. 4) for separating the solid constituents 3 from the wastewater 1, which unit is connected by a pipeline 16 to the container 6 for 8002019-1 31 storage of the wastewater separated in the unit 4 and bringing its volume and composition to the average volume and the average composition, respectively, and on the other hand an electrochemical treatment unit 8, which is connected to the container 6 by a pipeline 17. Between the container 6 and the unit 8 a pump 18, which is intended to pump the waste water brought to the average volume and composition from the container 6 to the electrochemical treatment unit 8, which is connected by a pipeline 19 to a container 20 for the purified water 14. The container 20 is through a pipeline 21 connected to a pump 22 for pumping clean water over ship tables.

The unit for separating solids from the wastewater is connected by a pipeline 23 to a pump 24 for removing the mixture 13 of the solids 3 and impurities 12, which during the electrochemical treatment were isolated from the separation unit 4.

The pump 24 is connected to the container 6 through pipes 23, 25, 26 and to the electrochemical treatment unit 8 via pipes 23, 25, 27-30. The pump 24 is connected to the separation unit through the pipes 23, 25, 27 and 31. 4.

To empty the unit 8 for electrochemical treatment from the waste water brought to the average volume and composition, valves 32 and 33 were used. To empty the container 6 and the separating unit 4, valves 34 and 35, respectively, were used. If necessary, one can between the separating unit 4 and the pump 24 arranges a crusher (a atomizing device) 36, which is intended to be connected and disconnected by means of a valve 37. The container 6 for storing the waste water and bringing its volume and composition to the downhole and the average composition is provided with a recirculation pipe 38. , which is intended to wash away the precipitate formed in the container 6 and control the supply speed of the wastewater brought to the average parameters to the electrochemical treatment unit 8, which is connected by a pipeline 39 to a container 40 arranged in the separation unit 4, which is below the low pressure to be generated by the fan 10.

The container 40 is provided with a pipe nozzle 41, the lower end of which is immersed in the liquid, which is continuously located in the lower part of the separating unit 4 and which is inserted into this part during the separation of the solid constituents and together with those at the electrochemical treatment isolated the contaminants.

The container 40 is further provided with a hole 42 for ventilating the separating unit 4. The separating unit 4 is provided with an inlet pipe socket 43, below whose outlet holes are arranged on a shaft 44 with a conical filter 45. Below the base of the filter 45 a receiving funnel 46 for the separated waste water is arranged. A drive device for the conical filter is not shown in the drawings.

The separation unit 4 (Figs. 5 and 6), the electrochemical treatment unit 8, the container 6 (Fig. 5) and the container 20 (Figs. 5 and 6) for clean water have compact outer dimensions and are arranged on a common platform 47. In the center part of the unit 8 (Fig. 5) is at least one air intake hole 48 occupied. The plant is connected through the pipe nozzle 43 to a ship-borne, not shown waste water source. An energy unit 49 is arranged on the housing of the separation unit 4. The electrochemical treatment unit 8 is arranged on the containers 6 (Figs. 5) and 20 (Figs. 5 and 6). The separation unit 4 is supported by the platform 47. Such an arrangement of the containers 6 and 20 as well as the units 4 and 8 contributes to increasing the structural rigidity of the plant and reducing its outer dimensions. Arranged along the upper edge of the unit 8 is a pneumatic device 50 (Figs. 4-6) for removing the foam formed in the electrochemical treatment unit 8. The fan 10 is driven by an e-bed clamp 51 (Fig-5) - The pumps 24 , 18 and 22 are driven by electric motors 52, 53 and 54 respectively.

The unit 4, the container 6 and the unit 8 are formed with bottom parts, which are inclined in the direction of pipelines 31 (Figs. 4,5) 26, 29 and 30, respectively.

The electrochemical treatment unit 8 (Fig. 7) consists of a sectioned container 55, which is divided into sections by means of partitions 56, 57 and 58 (Fig. 8). In the center part of the sectioned container 55 (Fig. 7) is arranged vertically a pipe 59 intended for receiving purified liquid, which is hydraulically connected to a means 60 for discharging the liquid constructed in the form of an outlet pipe and to the section 61 of the container 55, in which the waste water finally decontaminated. The upper end of the tube 59 projects above the liquid level in the container 55.

In a section 62, active aluminum electrodes 63 are arranged, while in sections 64 and 61 inert graphite electrodes 65 and 66, respectively, are arranged. The electrodes 63, 65 and 66 are connected in parallel with the energy unit 49 (Fig. 5.6) so that when the supply circuit for the electrodes is broken or the electrodes are damaged in any section of the electrochemical treatment unit, electric current continues to flow. between the electrodes in the other sections.

To prevent the electrodes from being passivated by oxides and insoluble compounds formed during electrolysis, the polarity of the electrodes can be changed automatically.

A section 67 (Fig. 7) is intended for removing gas bubbles and coagulated colloidal contaminants from the wastewater.

The pneumatic device 50 comprises an air duct 68, which is arranged along the upper edge of the electrochemical treatment unit 8 and is provided with air outlet holes 69, which are received in the surfaces of the air duct 68, which face the inner space of the unit 8.

In order for air to be able to flow uniformly out of the holes 69, curtain-shaped members 70 are arranged in the upper part of the air duct 68.

The walls of the air duct 68 are further provided with a hole 48 with a pipe socket 71 for receiving air from the atmosphere. Arranged in the air duct 68 under the pipe socket 71 is a partition wall 72 (Fig. 8), which is intended to uniformly distribute air over both halves of the air duct 68. At the corners of the air duct 68 are arranged guide means 73, which are intended to limit vortex formation in the air flows and eliminate stagnation zones at the corners of the air duct 68. After each air outlet hole 69 are arranged guide means 74, which are intended to direct a part of the air flow towards the center portion of a space , which is formed by the air line 68, the liquid surface of the electrochemical treatment unit 8 and the lid of the unit 8 not shown. In the air line 68, a partition 75 is formed at the side opposite the pipe nozzle 71, which is intended to prevent the opposing air flows in the air line 68 are mixed with each other. The partitions 72 and 75 are furthermore intended to prevent the liquid to be purified from flowing out of one half of the air duct 68, into its other half, when the plant is inclined.

In the center part of the unit 8, above the upper limit of the liquid level in the unit 8, a foam receiving means 76 (Fig. 7) is arranged, which is connected to the fan TO (Figs. 4-6) intended to generate low pressure in the part arranged in the separation unit 4. the container 40, the foam receiving means 76 and in the space delimited by the liquid surface in the unit 8, its lid and the air duct 68. The foam with the contaminants suspended therein flows out of the foam receiving means 76 through the pipeline 77 and further through the pipeline 39 (Figs. 4-6) into the container 40, from where it is fed into the separation unit 4, where it is mixed with the solid constituents after which it is removed from the unit 4 by means of the pump 24. In a space delimited by the foam receiving means 76 (Fig. 8) outside and the inside of the air duct 68, are arranged vertical partitions 78, which are intended to divide this space into sections and placed so that their lower edges are immersed in the liquid in the electrochemical b the handling unit 8 and their upper edges at least extend up to the upper edge of the air duct 68. The partitions 78 can also be arranged above the upper edge of the air duct 68 and extend up to the lid of the unit 8. By dividing the space formed by the air line 68 and the liquid surface of the electrochemical treatment unit 8 into sections, the partitions 78 prevent the air flows, which are directed from both halves of the air line 68 towards the center part of said space, from mixing with each other. .

The partitions 78 further promote that the foam flows in the direction of the foam receiving means 76. To prevent the air flows from flowing above or below the partitions 78, their lower edge is immersed in the liquid in the unit 8, while the upper edge of the partitions 78 is at least flush with the air duct. 68 upper edge (the cover of the onlet unit 8 abuts against the upper edge of the overhead line 68). If a gap is formed between the lid of the unit 8 and the upper edge of the air duct 68, the upper edge of the partitions 78 must be in contact with the lid of the unit 8.

The electrochemical treatment unit 8 is provided with a pressure pipeline 17 (Fig. 5,8) for feeding the waste water brought to the average volume and composition into the unit 8. The purified and decontaminated waste water is removed from the section 61 (Fig. 5,8). .7) through a double bottom part 79 (fig. 7,9), a hole 80 in the pipe 59 for receiving clean liquid, the liquid discharge means 60 built up in the form of an outlet pipe and through the pipe line 19 (fig.5) to the container 20 for clean wastewater.

The section 61 can be connected to the pipe 59 through a pipe 81 (Figs. 10, 11).

The means 60 for discharging pure liquid can be arranged in the tube 59 for receiving pure liquid, as shown in Fig. 12. In this case, the waste water is removed through the bottom part of the unit 8.

Fig. 13 shows how the foam receiving means 76, which is arranged in the center part of the electrochemical treatment unit 8 above the upper limit of the liquid level in the unit 8, is connected to the fan 10, which is intended to generate low pressure in the container 40 container 40, the foam receiving means 76 and in the space delimited by the liquid surface in the unit 8, its lid and the air duct 68. In order to separate foam from air, a partition wall 82 is arranged in the container 40.

Figs. 14-16 show a perspective view of different embodiments of the overhead line 68.

The air line 68 shown in Fig. 14 has, seen in a plan view, the shape of a hexaeder, while the air line shown in Fig. 15 is circular. The air duct 68 according to Fig. 16 is in the form of a hexahedron, the electrochemical treatment unit 8 being cylindrical. 1: Fig. 17 shows the unit 4 for separating a solid constituents from the waste water with the conical filter 45 arranged therein.

In the unit 4, below the outlet hole of the pipe nozzle 43, on the shaft 44, the conical filter 45 is arranged, the side surface 83 of which is bent out towards the tip of the filter 45.

The side surface 83 of the conical filter 45 consists of a so-called evenly twisted net. 8002019-1 36 At the tip of the filter 45, a screen 84 is arranged on the shaft 44. Below the base surface of the filter 45 is arranged a funnel 46 for receiving the separated waste water, which is provided with the outlet pipe socket 16 connected to the container 6, a so-called so-called shaft 44 is arranged. skirt-shaped member 85, which is in the form of a cylinder of elastic material, for example rubber, and is separated from the base surface of the filter 45 by a distance exceeding the maximum particle size of the solid contaminants to be separated. Side surface 83 of the conical filter 45 is folded at an obtuse angle. The skirt-shaped member 85 is arranged such that its lower edge extends at least to the base level of the conical filter 45, but it may be arranged below the base level.

In the funnel 46 for receiving clean waste water, along the upper edge of the funnel 46 towards the base of the conical filter 45, an annular tube 86 is arranged with holes 87 (Figs. T8, T9), which are received in the tube surface facing the filter. 45 (fig, T7) inside. The annular tube 86 is connected by a pressure regulator (not shown) to a source (not shown) of the medium TS, which is intended to reduce the adhesive force of the contaminants at the filter surface of the filter 45.

The hole 87 of the pipe 86 (Fig. 19) may expand in the direction of the outer wall of the pipe 86 or may be provided with conical diverging nozzles 88 (Fig. 20). In the unit 4 (Fig. T7) for separating solid constituents the pipe 16 is provided with a mesh overflow 89 which is intended to ensure that the system functions normally, when the conical filter 45 is rendered inoperable. The condition of the side surface 83 of the conical filter 45 can be visually checked through a peephole 90.

The system works as follows.

Wastewater from the ship-borne sanitary equipment is fed through the pipe socket 43 (Fig. 4) to the conical filter 45, where coarser constituents of contaminants (eg paper, cotton wool, food waste products, etc.) are removed from the wastewater. The partially purified wastewater is fed into the receiving funnel 8002019-1 I 37 46 and flows through the tube 16 into the container liner for storing the separated wastewater and bringing its volume and physical and chemical composition to an average volume and average composition, respectively. and the average composition brought (so-called equalization) the wastewater accumulates in the container 6. After the wastewater has reached a predetermined level in the container 6, a sensor (not shown) is affected, at the same time as the supply current is supplied to the electrodes 63, 65, 66 (Fig. 7) (Fig. 4), at the same time as the pump 18 is started, which feeds the equalized wastewater through the pressure pipeline 17 into the electrochemical treatment unit 8.

A portion of the liquid is returned through the pipeline 38 to the container 6, where it washes away the precipitate accumulated in the container 6 and stirs the waste water in the container 6 to bring the physical and chemical composition of the waste water to the average composition and ensure the desired flow rate for equalization. is introduced into the electrochemical treatment unit 8 by recirculating a part of the liquid through the pipeline 38.

The wastewater is fed through the pipeline 17 (Fig. 8) in the lower part of the unit 62 section 62 (Fig. 7), where the active aluminum electrodes 63 are arranged parallel to each other. The wastewater to be treated flows through the gaps between these electrodes. The colloidal contaminants present in the wastewater coagulate under the influence of the electric field and aluminum ions, which are transferred to the solution under the influence of electric current, at the same time as hydrogen gas is developed at the electrodes acting as cathodes. The evolved hydrogen gas forms gas microbubbles, which remove the coagulated and suspended atomized contaminants to the liquid surface, thereby forming foam at the surface of the liquid to be treated. The liquid then flows past the partition wall 56 and is fed in the direction from top to bottom in the section 64, where a parallel row of the inert graphite electrodes 65 is arranged. When the electrodes 65 are flowed through by electric current, hydrogen gas is evolved therewith, whereby the impurities are isolated from the liquid to be treated by flotation. At the anodes, decontamination substances, ie chlorine, hydrogen peroxide and ozone, are developed in this case. The liquid to be treated then flows out of the lower part of the section 64 under the partition 58 (Fig. 8,9) into the section 67, where the contaminants with the finest hydrogen bubbles are removed from the liquid, which contaminants are carried by the one from the section 64 downward fluid flow. From section 64, the liquid flows into section 6T with the graphite electrodes 66 arranged therein parallel to each other. In section 61, the contaminants remaining in the liquid are removed by flotation, and the liquid is finally decontaminated. The finally purified liquid is fed from the lower part of the section 6T either under the double bottom part 79 (Fig. 7.9, T2) or through the tube 81 (Fig. T0.11) in the groove: 59 (Fig. 7) for receiving pure liquid , from which it is fed through the tubular means 60 for discharging pure liquid and nm fl ednhkæn'w (Figs. 4-6) into the container 20 for clean water, from which the purified liquid is transferred through the pipeline 21 by means of the pump 22 to further utilization steps or is removed over table.

The pure water can be removed from the unit 8 through the member 60 (Fig. 12), which is built up in the form of a tube, which is arranged in the tube 59 for receiving pure liquid. In this case, the wastewater is removed through the bottom part of the unit 8. The unit 8 so designed becomes, technologically speaking, easier to manufacture.

In the electrochemical treatment of the wastewater, the coagulated and atomized impurities which are removed to the surface of the liquid to be treated, by means of the hydrogen bubbles developed by the electrolysis, form the foam layer 9 (Fig. 1.8) at the liquid surface.

In order to be able to remove the foam during the electrochemical treatment of the waste water, a low pressure (vacuum) is generated in the container 40 (Figs. 4-6, 13) by means of the fan 10 (Figs. 4-6, 13), which pressure through the pipeline 77 (Fig. 13) is transferred to the foam receiving means 76 and the space defined by the liquid surface in the unit 8, its lid and the air duct 68. The generated low pressure acts so that atmospheric air flows through the nozzle 71 and the hole 48 into the air duct 68, from where it passes through the holes 69, which are intended to form the opposite air flows, are introduced into the foam receiving means 76 and entrain the foam.

The foam entrained by the atmospheric air flows from the foam receiving means 76 flows out through the pipeline 77 into the container 40 arranged in the separation unit 4. The foam is extinguished by the flow rate and flow direction of the foam and the air in the pipeline 77 and the container 40 suddenly changing. The formed suspension is introduced through the pipe nozzle 41 into the lower part of the separating unit 4, where it is mixed with the solid constituents separated from the waste water by means of the conical filter 45 (Figs. 4, 6, 17).

Air and hydrogen, separated from the foam by the fan 10, are diverted to the atmosphere. The partition 82 (Fig. 13) is intended to separate droplets of the liquid entrained by the air flows. The solid constituents of the contaminants in the waste water, which are adhered to the side surface 83 of the filter 45 (Fig. 17), are removed therefrom by the filter 45 periodically In order to be able to more evenly distribute the wastewater stream over the side surface 83 of the conical filter 45, the wastewater is supplied to the tip of the filter 45, the smooth surface screen 84 contributing to a better distribution of the contaminants over the side surface 83. This results in that the contaminants are mainly precipitated on the side surface 83 at such a distance from the axis of rotation of the filter 45 that the centrifugal forces generated by the rotation of the filter 45 are large enough to be able to remove the contaminants from this surface.

In order to reduce the amount of water which, together with the contaminants, is introduced into the lower part of the separating unit 4, the side surface 83 is folded towards the tip of the conical filter 45 at an obtuse angle in order to be able to retain the waste water draining along the side surface 83. .

When the load on the filter 45 suddenly increases, the water which has not had time to filter through the side surface 83 is retained by this unfolded edge. In addition, the contaminants retained by the unfolded side surface 83 can be easily removed from the side surface 83 afterwards during regeneration of the side surface 83, which is made possible by suitable selection of the unfolding angle of the side surface 83 and by the contaminants being separated by a sufficient distance from the axis of rotation of the filter 45.

The skirt-shaped member 85 arranged in the separating unit 4 is intended to reduce the speed of movement of the solid components which are discarded from the side surface 83 during the filtration of the waste water and during the regeneration of the filter surface of the filter 45 under the influence of the centrifugal forces generated. , when the filter 45 is periodically caused to rotate. The means 85 is furthermore intended to prevent the solid components from sticking to the walls of the separating unit 4 and these walls eroding.

The side surface 83 of the conical filter 45 is regenerated automatically. After a predetermined amount of waste water has passed through the side surface 83, the level sensors (not shown) arranged in the container 6 are actuated, which start the drive device for the shaft 44. The operating time of this drive device is preset by a time relay (not shown). Before the rotation of the filter 45 begins, the medium intended to reduce the adhesive force of the contaminants at the filter surface of the filter 45 is fed through the annular tube 86 to the inside of the filter 45. The medium supply ceases at the same time as the drive device stops. Said medium can be supplied before the filter 45 has started to rotate and be interrupted, when the drive device of the filter 45 is started.

The first embodiment of the media supply is suitably used in the treatment of only so-called taps. When treating the entire waste water formed on board the vessel, the second embodiment is suitably used for supplying the adhesive reducing medium.

When the plant operates under automatic operating conditions, a certain pressure should be selected, at which said medium is supplied to the inside of the conical filter 45. However, when the filtration conditions are disturbed by large particle size contaminants or high adhesion contaminants ending up on side surface 83, the pressure of the medium can be significantly increased. The adhesion reducing medium 15 (Fig. 17) is fed through the holes 87 (Fig. 19) or the nozzles 88 (Fig. 20) in the annular tube 86, which are designed so that the jets flowing out of the holes 87 and the nozzles 88, respectively, uniformly bridge the entire inside of the conical filter 45.

The shafts 87 (Fig. 19) which are received in the annular tube 86 and expand towards its outside ensure the optimum hydrodynamic outflow conditions for the adhesion reducing medium. This is further promoted by the fact that the holes 87 are provided with the nozzles 88 (Fig. 20).

When carrying out the work for preparatory inspection and conservation of the plant and when troubleshooting, the separation unit 4 (fig. 4), the electrochemical treatment unit 8 and the container 6 are emptied by means of the pump 24.

The units 4 and 8 as well as the container 6 can be emptied simultaneously or individually. When emptying at the same time, the valve 37 is stopped or the valves 32-35 are emptied. In the case of individual emptying, the valve 37 is closed or only the valve belonging to the respective unit or container is opened.

In order to facilitate the transport of the solid constituents through the system of pipelines and the destruction of them in a suitable ship furnace, these constituents are atomized by means of the crusher 36 (Figs. 4-6).

The fan 10 is intended to, in addition to transporting the foam and removing hydrogen gas from the plant, ventilate the units and containers by keeping the low pressure constant in the plant and preventing unpleasant odors from entering ship premises.

The curves shown in Fig. 21 represent the test results for the operation of the plant for a period of 90 days. In Fig. 21, the concentration (K) of suspended solids and the biochemical oxygen demand (BS5) plotted along the ordinate are plotted, with the content of carbon bacteria in untreated wastewater and in clean wastewater being 10 - 1014 bacteria per liter and 20 bacteria per liter, respectively. Curve E represents the variation in the quality of untreated sewage n iaoo2o19-1 water (curves G 'and H' represent the variation in the content of suspended solids and the variation in the biochemical oxygen demand BS5, respectively).

Curve F represents the quality of the treated wastewater after treatment by the plant. This curve shows that the content of suspended solids (curve G) and the biochemical oxygen demand (curve H) meet the requirements of the International Convention of 1973 with consideration for the prevention of water basins being polluted by wastewater from ships.

The method and plant according to the invention for wastewater treatment can be used very efficiently for vessels of any type.

Claims (19)

8002Û19 "1 413 Patentkrav A process for wastewater treatment by treating it in several successive steps, wherein in the first step solid constituents are separated from the liquid and collected, in the second step the liquid separated in the previous step is homogenized with respect to volume equalization and physical / chemical composition, why the liquid thus homogenized in the third step is subjected to an electrochemical treatment at a sufficient flow rate for the formation of a foam layer (9) on the surface with subsequent separation of impurities from purified water (14), characterized in that - in the first stage during the separation of the solid constituents (3) a negative pressure is generated, which in the third stage is maintained during the electrochemical treatment in such a way that - under the influence of the negative pressure air currents (11) are formed in the foam layer (9) , which drives the foam from the edge areas of the foam layer (9) towards its center, and is transferred therefrom on such a manner as to the first step of separating the solid constituents (3) from the liquid, that the foam is mixed with the solid constituents (3), and that - to the zone located below the center of the foam layer (9) electrochemically purified water is led ( 14) and is taken out of this zone. Method according to claim 1, characterized in that the solid constituents (3), before the foam is mixed with them, are separated by filtering the waste water (1) through a conical filter surface (2) by passing the waste water (1) in the direction of its tip, after which the solid solids (3) accumulated at the filter surface (2) are removed by centrifugal forces and by the action of a medium (15) intended to reduce the adhesion force of the contaminants at the filter surface (2), and under pressure on the inside of filter surface. 8002019-'1 1114 (2), to the outside of which the waste water (1) is supplied. Method according to claim 2, characterized in that the adhesion-reducing medium (15) is applied after 50-60% of the filter surface (2) has been clogged. Method according to claim 2, characterized in that the adhesion-reducing medium (15) consists of hot water. Method according to claim 2, characterized in that the adhesion-reducing medium (15) consists of a mixture of steam with water. Method according to claim 2, characterized in that the adhesion-reducing medium (15) consists of a mixture of water and detergent, for example surfactants. Method according to claim 2, characterized in that the adhesion-reducing medium (15) is constituted by steam. Method according to claim 2, characterized in that the adhesion-reducing medium (15) consists of hot air. Plant for carrying out the method according to claim 1, which comprises a unit (4) for separating the solid constituents (3) from the waste water (1), a container (6) connected to the unit (4) by a pipeline (16) for collecting and homogenizing the waste water, (1), a unit (8) provided with electrodes (63, 65, 66) for an electrochemical treatment, which is provided with means for supplying and discharging waste water and is connected to the container (6 ) through a pressure pipeline (17), characterized in that a pressurized container (40) is arranged in the unit (4) for separating the solid components (3) from the waste water (1), which container is provided with a pipe socket (41), the lower end of which is immersed in the liquid, which is continuously in the separation unit (4), the container (40) being connected to the unit (8) of the the electrochemical treatment, which is provided with a pneumatic device (50) to remove the foam formed during the electrochemical treatment. Plant according to claim 9, characterized in that the unit (8) for the electrochemical treatment is constructed in the form of a sectioned container (55) with a tube (59) arranged vertically in its center part, which is intended for receiving of purified water and hydraulically connected to a means (60) for withdrawing purified water and to the section (61) of the container (55), the upper end of the tube (59) for receiving purified water projecting above the liquid level in the container (55). Plant according to claim 9, characterized in that the pneumatic device (50) for removing the foam comprises partly an air line (68), which is arranged along the upper edge of the electrochemical treatment unit (8) and provided with air outlet holes (69), which are accommodated in the surfaces facing the interior of the unit (8), and with air intake holes (48), and partly a foam receiving means (76), which is arranged in the center part of the unit (8) above the upper limit for the liquid level in the unit (8) and connected to the fan (10), which is intended to generate negative pressure in the container (40) arranged in the separation unit (4), in the foam receiving means (76) and in a space delimited by the liquid surface in the unit (8), its cover and the overhead line (68). Plant according to claim 11, characterized in that vertical partitions (78) are arranged in a space delimited by the outside of the foam receiving means (76) and the inside of the air duct (68), which partitions "eat 8002019-1 _ ae intended therein. to divide said space into sections. Plant according to claim 12, characterized in that the vertical partitions (78) are arranged such that their lower edges are immersed in the liquid and their upper edges extend at least to the upper edge of the air duct (68). Plant according to one of Claims 9 to 13, characterized in that the unit (4) for separating the solid constituents (3) from the liquid in the waste water (1) comprises an inlet pipe (43) for the waste water (1). , under whose outlet hole on a shaft (44) is arranged a conical filter (45), the side surface (83) of which is folded out in the direction of the tip of the filter (45), at which a screen (84) is arranged on the shaft (44), wherein a receiving funnel (46) provided with an outlet pipe socket (16) for the separated waste water is arranged below the base of the conical filter (45), while a skirt-shaped member (85) is arranged coaxially with the shaft (44). ) in the form of a cylinder of elastic material separated from the base surface of the filter (45) by a distance less than the maximum particle size of the solid phase constituents to be separated. Plant according to Claim 14, characterized in that the side surface (83) of the filter (45) is folded out at an obtuse angle. Plant according to claim 14, characterized in that the skirt-shaped member (85) is arranged such that its lower edge extends at least to the base surface of the conical filter (45). Plant according to claim 14, characterized in that an annular tube (86) is arranged in the receiving funnel (46) for separated liquid along the upper edge of the funnel (46) facing the base of the conical filter (45), which tube (86 ) 8002019-'1 4? are provided with holes (87) which are received in the surface of the tube (86) facing the inside of the filter (45), the tube (86) being connected by a pressure regulator to a source of the medium (15) which is intended to reduce the adhesion of the contaminants to the filter surface of the filter (45). Plant according to claim 17, characterized in that the holes (87) in the annular tube (86) expand in the direction of the outer wall of the tube (86). Plant according to claim 17, characterized in that the holes (87) in the annular tube (86) are provided with conical diverging nozzles (88).