FI74695C - Process and apparatus for wastewater treatment. - 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treated liquid (14) is directed towards the area underlying the central portion of the foam layer (9) and subsequently withdrawn therefrom.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

· * § ** · I ANNOUNCEMENT

«ISPlt [B] (11) utläggimingsskrift 74 69 5'-r" (45) “v- (51) Kv.lk.4 / lnt.CI.4 C 02 F 9/00, 1/46, B 63 J 4/00

SUOMI FINLAND

(FI) (21) Patent application-Patentansökning 8008l6 (22) Application date - Ansökningsdag 17.03 * 80

National Board of Patents and Registration (23) Start date - Giltighetsdag 1 7.03.80

Patent- och registerstyreleen {41) Tuiiutjublicisen-bi, v „offo ,,. I, g 22.09.80 (44) Date of publication and earmarked publication - -jq 11 g 7

Ansökan utlagd och utl skiiften publicorad * (86) Kv. Application - Int ansökan (32) (33) (31) Privilege claimed - Begärd priority 21.03 * 79 11.05.79, 11 * 05 * 79, 11.05.79, 05.07.79, 05.07.79, Ο5.Ο7.79 USSR ( SU) 2733610, 2757001, 2757003, 2757004, 2777953, 2777954, 2777952 (71) Leningradsky Tekhnologichesky Institut Kholodilnoi Promyshlennosti, ulitsa Lomonosova 9, Leningrad, USSR (SU) (72) Gennady Sergeevich Zenin, Leningrad

Semen Alexandrovich Bogatykh, Leningrad,

Vladimir Nikolaevich Yatsenko, Leningrad,

Anatoly Timofeevich Soloviev, Leningrad,

Vadim Maximovich Shamshin, Leningrad,

Viktor Dmitrievich Veselkov, Vyborg, Leningrad Oblast,

Vladimir Efimovich Nefedov, Leningrad,

This invention relates generally to the control of environmental pollution and, more particularly, to methods and apparatus for treating sewage.

It is well known that the prevention of environmental pollution is a global problem today. Pollution of pools, rivers, seas and oceans is recognized as a particularly serious part of the biosphere pollution problem. "Sewage water" here means water which has been used in the household or in production and which has therefore received various, additional impurities (pollutants) which cause a change in its chemical composition or physical properties. The sewage generated on board as a result of the vital functions of the ship’s crew represents a class of its own in these contaminated sewage fluids. Given that ships at sea are highly mobile means of transport, there is always a risk of pollution spreading to different parts of the world 74695 and thus to the transmission of various infectious diseases and communicable diseases.

It is for this reason that many nations of the world seek to prevent ships from entering their territorial waters that do not have sewage treatment and sterilization equipment.

Pursuant to the 1973 International Agreement, treated sewage must meet certain requirements concerning the suspensions and coliforms it contains and the biochemical oxygen demand. In addition, this treated sewage must have the following characteristic values. for indices: - suspension content 50 mg / l (inland test); 100 mg / l (test on board); - coliform content 250 bacteria / 100 ml; - biochemical oxygen demand 50 mg / l.

Progress has already been made in the development of ship sewage treatment plants and various treatment processes, taking into account precisely the application in ships. Ship effluents usually have clear special properties, the most important of which are the large variation in effluent supply, the high concentration of contaminants, and the presence of large contaminants in these effluents that are virtually incapable of undergoing any physicochemical changes due to ship effluent.

Today, many different methods and flow process diagrams have been proposed for sewage treatment. However, only a limited number of these methods are suitable for use in actual ship conditions due to the special nature of the operation of sewage treatment plants on ships. The handling of organic compounds on board requires a small, efficient and simple plant capable of operating automatically, which can be started and stopped frequently and whose performance is satisfactory both when the salinity of the water varies and when the ship tilts and swings.

The simplest method of purifying a ship's sewage involves the reduction of contaminants in the water to be treated in stages and their chemical purification (e.g., U.S. Patent 3,472,390). The apparatus implementing this method includes a de-74695 sintering device, a crusher and a pump for transferring sewage. However, the ship's sewage treated with this equipment and method does not comply with current national and international pollution regulations and requirements, due to the fact that this method can only treat the sewage but does not reduce its suspension concentrations or biochemical oxygen demand. use.

Some biochemical methods for treating and purifying sewage have been used on a large scale (e.g., U.S. Patent 3,460,677). According to said patent, the sewage is treated with an active slurry while pressurizing the sewage. The device used to carry out the method includes a divided tank, a piping system for transporting sewage and a sewage aeration system. This method and device is known for a harmfully long start-up period (about 14 days) and a rather long cleaning process that takes at least 12-24 hours. Due to the latter, the device must be exceptionally large for large sewage treatment. Sewage treated with this method must not contain fats or petroleum products, as these impurities have been found to have a detrimental effect on the viability of the activated sludge. In addition, in the disinfection of sanitary equipment installed on a ship and in various sections of the ship, the active sludge is easily contaminated when disinfectants enter the equipment carrying out this method, leading to breakage or malfunction of the equipment.

According to the current requirements, the treatment of the ship's sewage is absolutely necessary only within territorial waters and enclosed sea areas. Therefore, sewage treatment only needs to be performed when the ship is in these areas. In areas that are open to the discharge of contaminated sewage, the device can be stopped, i.e. sewage treatment is not mandatory. But due to the long start-up time of a device using a biochemical purification method, such downtime periods are not allowed, resulting in a high need for energy and reagents. In addition, the interruption of the operating air of the biochemical cleaning device results in a considerable shortening of its service life. In order to carry out the method efficiently, a uniform contaminant load is a prerequisite for achieving the normal viability of the active sludge used in the method / which is almost impossible under ship conditions. Due to these properties, the biochemical method and device for treating ship sewage do not meet the requirements for ship equipment.

In addition, a physicochemical method for purifying sewage is known (e.g. DE patent 2,543,353). According to this patent, the ship's sewage treatment method uses a sewage collection tank, and by adding chemicals and decomposing the solids solids, the sewage is uniformized and fed to a pre-clarification tank where the sludge settles to the bottom while the fat rises. The oxygen released by electrolysis immediately oxidizes the organic matter in the sewage, while the hydrogen, which is also released by electrolysis, develops acids with the inorganic substances contained in the water. The effect of the acids formed neutralizes all the different microorganisms, after which the treated water with still solids is fed to the post-clarification tank, and then the slurry from the pre-clarification tank, electric reactor tank and post-clarification tank is collected in a sludge collection tank. out to sea.

The apparatus used to carry out the described method includes a collection tank, a tank for chemicals, equipment for dosing and decomposition, a pre-clarification tank, an electric reactor, a post-clarification tank and a sludge collection tank, all mounted in a common frame in a small rectangular shape.

The method and apparatus described for the physico-chemical treatment of ship's effluent are known from a complex reagent system and a complex structure of the apparatus because the chemicals used in the treatment must be metered. Hydrogen generated during operation of the device is not removed, which poses a risk of explosion of the device. The removal of sludge from the various sewage treatment units is performed in this method and apparatus by means of pre-clarification (standing in the pre-clarification tank, electric reactor tank and post-clarification tank). However, the normal conditions in a ship with constant vibration, rocking and tilting adversely affect the settling of the suppression particles, and therefore the efficiency of the cleaning in the device also deteriorates.

When the method, the solids content of the sewage undergoes crushing before treatment, which incurs additional costs for subsequent removal from the sewage due to both the energy required for cleaning and the time required for the sewage to stand still, not to mention the increase in disinfectant consumption.

In order to keep the equipment used to carry out this treatment method in normal use, the ship must have a large stock of chemicals, which must have a specially equipped compartment for storage, which is also the reason for the limited use of the physico-chemical sewage treatment method and equipment.

Today, combined methods of treating ship sewage are increasingly being used, as they apparently take full advantage of the advantages of the various methods previously developed.

Today, for example, a method is used which combines the physical removal and decomposition of impurities by electrochemical oxidation. One such typical combined method is disclosed in U.S. Patent 4,009,104, the technical spirit of which is closely related to the subject matter of the present invention. The ship's sewage treatment method of this patent performs sewage treatment in a series of successive steps, the first step being to remove solids from the water and collect them; the next step is to collect the sewage separated in the previous step and level it with respect to the average volumetric load and physicochemical composition, after which the leveled sewage undergoes an electrochemical treatment, followed by insulation of impurities and treated water the suspension impurities settle to the bottom, and the liquid from which the solids have been partially removed is pumped through the filter system.

An apparatus for carrying out said method of purifying sewage comprises a separator for removing solids from the sewage to be treated, a sewage collection and equalization tank connected by a pipeline to the separator for removing solids, an electrochemical treatment device with a liquid in which electrodes are immersed, and - and a surge tank with a pressure pipeline, a tank that receives treated water, filters, a mains appliance, a circulating tank, pumps and pipelines with valves. The device works by pumping the separated sewage through an electrochemical treatment plant, filters and a circulating tank. The electrochemical treatment device included in the unit is an electrolytic cell shaped as a hollow, cylindrical housing which acts as a cathode containing anodes, the anodes being made of graphite or platinum-coated steel. The housing of the electrolytic cell is closed. The electrically conductive solution and the sewage water flow through the ring between the anode and the cathode. The solids separator contained in the unit causes the solids contained in the sewage to be removed by directing them to a screen of the conveyor or centrifuge type.

In a method and apparatus for treating sewage such as that described, the suspension particles which are normally expected to settle in the circulating tank do not in practice do so under ship conditions of continuous vibration, heeling and swaying, and particle removal is mainly accomplished only by filters. When operating under excessive loads, these become clogged quickly and often require replacements or cleaning of the work surface. As the suspension particles do not settle efficiently enough in the circulating tanks, they remain in the valve system, which causes disturbances here and impairs the reliability of the operation of the entire plant as well as the efficiency of the sewage treatment.

Due to the small surface area of the electrodes, the electrolysis cell of this unit is only able to operate at high current densities, which involves rapid overheating of water in the electrolysis cell and thus the cell must be disconnected from the sewage source from time to time. The latter is to blame for the poor performance of the electrolytic cell. In addition, when the current density is high, there is a significant increase in the active energy loss of the treated sewage liquid, which causes an increase in the cost of energy consumed per cubic meter of the treated sewage water. When the electrolytic cell has such a structure, the time spent by the sewage in the space between the electrodes is short, which results in a lower treatment efficiency because the electric field exerts an insufficient effect on the impurities. When sewage is treated in an electrolytic cell having this structure, electrochemical flotation phenomena are not utilized to remove impurities. Contaminants are removed either by allowing them to settle in a circulating tank, which does not lead to the required degree of efficiency due to ship tilt, rocking and vibration, as noted above, or by stopping them in filters, which interferes with the performance of the entire plant.

A sewage treatment process using a single electrode in an electrolytic cell does not provide sufficient efficiency or reliability because electrode wear or an open circuit at the point of contact between the inlet and the active electrode of the electrolytic cell results in the unit standing. Another factor which also leads to a decrease in the degree of purification of the sewage in the electrochemical treatment unit is the passivation of the active electrodes of the electrolytic cell.

The closed design of the cell, as well as the need to disconnect it frequently from the overall system of the unit, require complex valve equipment and pose a serious problem in the operation of the unit. Since the sewage water is pumped in the electrolytic cell from the bottom upwards by means of a pump, if the latter ceases to function, e.g. due to overheating of the liquid in the electrolytic cell, the already treated liquid mixes with the untreated liquid as it settles from the top to the bottom. Repeated treatment of a previously treated liquid causes additional energy costs in the treatment of sewage and the procedure itself takes more time. Moreover, an electrolytic cell having a structure of the type described is not capable of completing the entire sewage treatment process and therefore must be pumped through filters to remove all contaminants from the sewage.

The solids separating screen, which is placed in a straight direction relative to the flow of sewage, has a uniform shape. When the screen has such a structure, the sewage stream tends to fall on it mainly within the local area, which results in both solids quickly clogging the screen and lower solids separation efficiency. However, the unit is not equipped with any special means for cleaning the strainer. Against the problem of strainer clogging, a sieve of the conveyor or vibration type is sometimes used. But more complex movements of the sieve can only be achieved at the expense of accessories, which makes the structure of the sewage treatment unit more complex.

Thus, the complex methods and equipment described for the treatment of ships' sewage do not achieve the required degree of efficiency or operational reliability. For the unit to operate normally, its filters and valves must be handled with extreme care, making the cleaning process more expensive and cumbersome. The efficiency of the cleaning process also suffers due to the fact that the liquid treated and untreated in the circulation system of the unit flows through the same pipelines.

The high explosiveness of the unit must also be noted, as it has no means of removing the hydrogen formed in the purification process that takes place in the electrochemical purification unit, i.e. the electrolytic cell. In addition, the unit does not have a ventilation system, which is why a bad smell penetrates the ship's compartments. The design principle of the electrochemical cleaning unit and the solids separation unit and the connection between these devices do not ensure efficient and reliable treatment of sewage under ship conditions, i.e. when the ship is constantly vibrating, tilting, rocking and other harmful phenomena occur.

The main object of the present invention is to develop a method and apparatus for purifying sewage, in which the directions of flows in the sewage solids separation unit and impurities in the electrochemical treatment unit and treated water 9 74695 must be arranged and and efficiency in swinging, tilting and vibrating the vessel containing this equipment, while simplifying the structure of the equipment.

To achieve this main goal, a method for purifying sewage has been developed by treating it in several successive steps, in the first step the solids are separated from the liquid and collected, in the second step the liquid separated in the previous step is homogenized for volume equalization and physico-chemical composition, thus the homogenized liquid is electrochemically treated in the third step. at a flow rate sufficient to form a foam layer on the surface, after which the impurities are separated from the purified water, and in accordance with the invention a vacuum is generated in the first step to separate solids during the electrochemical treatment so as to create opposite airflows to the foam layer. from the edge areas towards its center, from where it is moved in that way to the first stage in which the solids are separated from the liquid, that the foam mixes with the solids, and that electrochemically purified water is introduced into and removed from the zone below the center of the foam layer.

The apparatus implementing the method described above includes a unit for separating solid components from sewage, a tank connected to the unit for collecting and homogenizing sewage, an electrochemical unit for electrochemical treatment, the unit having means for supplying and discharging sewage that a vacuum vessel is placed in the unit for separating solid constituents from sewage, which tank is provided with a pipe socket, the lower end of which is continuously immersed in the liquid in the separation unit, the tank being connected by pipeline to an electrochemical electrically operated unit to remove the foam formed during processing.

By forming an electrochemical treatment unit in the foam layer without counterflows directing the foam from the edge areas of the foam layer towards its center and the treated liquid towards the area below the center of the foam layer, it is possible to collect foam and treated liquid in the part of the electrochemical treatment unit where they are subject to the smallest vertical displacements and their volume practically does not change when the sewage treatment plant moves sideways as the equipped vessel tilts and swings. This factor contributes to the rapid and efficient removal of foam and treated water from the electrochemical treatment unit.

By using a vacuum in the solids separation step (the unit that separates solids from the sewage) and further in the sewage electrochemical treatment step (the electrochemical treatment unit) it is possible to both form without counterflows at the top of the electrochemical treatment unit much simpler of the cleaning process and the structure of the device used to carry it out.

When electrochemical treatment is performed at sufficient flow rates of smoothed sewage to form a surface foam layer in the electrochemical treatment unit, electrochemical flotation phenomena can be utilized to force impurities on the surface of the liquid to be treated. By mixing the foam with solids separated from the sewage water, in the first stage of the solids separation unit, it is possible to remove both solids and electrochemical impurities from the same area, substantially simplifying the process flow diagram and the structure of the apparatus used to carry out this process.

By combining the solids separation unit, the electrochemical treatment unit and the sewage collection and 11,74695 equalization tank, the device requires as few valves as possible, which significantly simplifies its structure and operation and makes the operation of the device more reliable. In addition, such interconnection of the device allows the cleaning process to be performed without mixing the streams of treated and untreated liquid, which further enhances the treatment and improves the treatment efficiency of the sewage of the device. When sewage is treated in an electrochemical treatment unit, electrochemical foaming phenomena are utilized to remove impurities from the sewage, which removal is achieved by a rational coupling between the electrochemical treatment unit and the solids separation unit. via a pipeline to a solids separation unit from which they are subsequently removed. At the same time, the hydrogen formed in the electrochemical treatment unit and the ventilation of the device take place.

By using a container in the solids separation unit, the lower end of the tube seat is continuously immersed in the liquid in the separation unit, to which the liquid is fed during the solids separation process together with impurities separated in the electrochemical treatment process, an effective means of removing and disposing of foam which are separated in an electrochemical treatment unit and a solids separation unit.

Thus, the sewage treatment device of the present invention offers some structural and functional features that allow it to be utilized and highly efficient to perform sewage treatment under ship conditions with a high rate of continuous ship vibration, heeling and rocking.

According to one embodiment of the sewage treatment method, it is expedient that before the foam is mixed with the solids, these are separated from the sewage by filtration through a conical filter surface so that the sewage 74 695 is directed towards its tip. the force with which the contaminants adhere to the filter surface and the pressure applied to the inside of the filter surface to which the sewage is directed.

Filtration of sewage through a conical filtration surface combined with a supply of sewage to its peak promotes the best distribution of sewage over the entire filtration surface, resulting in very efficient separation of sewage solids and a steady and gradual increase in filtration surface contamination towards the bottom of the cone. At a later stage, the latter contributes to improving the efficiency of cleaning the filter surface when cleaning with centrifugal forces, which also increase in magnitude.

The effect of the applied medium on the filter surface, which reduces the adhesion of the contaminants to the filter surface and which is applied under pressure against the inside of this surface opposite to the side to which the sewage is fed, greatly aids in cleaning the filter surface. washing this surface with an anti-adhesive medium directed against the flow direction of the sewage. At the same time, since this medium is supplied under pressure, impurities are prevented from penetrating inside the filter surface, which in turn prevents impurities from penetrating from the filter surface into the liquid to be treated.

When the anti-adhesive medium is fed after 50-60% of the filter surface has been covered, it is possible to prevent the penetration of sewage into the accumulating solids and to increase the filtration efficiency by using the optimal hydraulic resistance on the filter surface.

For example, hot water can be used as the adhesion reducing medium. The hot water, which is fed under pressure to the inside of the filter surface, removes greasy deposits which adhere to the fibrous impurities, forming agglomerations which can later be easily removed from the filter surface by means of centrifugal forces 13 74695. When hot water is used as described, the fibrous impurities on the filter surface are released, which also leads to a more efficient cleaning of the filter surface by centrifugal forces.

A mixture of steam and water can also be used as an adhesion reducing medium. When such a mixture is used, the solids removed from the filtration surface are less prone to flooding and a smaller amount of water penetrates the solids as they are collected.

One alternative anti-adhesive medium is a mixture of water and detergents, e.g. surfactants.

When such detergents are added to the water, the adhesion of greasy impurities to the filter surface is further reduced, because at the same time the adhesion of the fibrous impurities to the surface is reduced, so that even less water can be used to clean the filter surface.

It is also advantageous to use steam as an adhesion reducing medium, whereby the exposure of the solids removed from the filter surface to the flood is reduced and less water penetrates the solids as they are collected.

Warm air also acts as an adhesion-reducing medium, which avoids excessive flooding of the solids remaining on the filter surface and provides a certain drying effect on these solids, which facilitates the further treatment of impurities removed from the filter surface.

In one embodiment of the apparatus for carrying out the sewage treatment method described above, the unit for electrochemical treatment contained in the apparatus is in the form of a divided tank with a pipe vertically arranged in its center for receiving purified water and connected to a hydraulically treated water outlet and a part of the purified water. the upper end of the receiving tube extends above the surface of the liquid in the tank. The compartment structure of the electrochemical treatment unit makes it possible to clean the treated liquid more thoroughly and efficiently by gradually transferring the liquid from one compartment to another, and in addition the hydraulic shocks associated with the tilting and rocking movements of the device are minimized.

By placing the treated liquid tube in the center of the receiving tank and connecting it only to the part of the tank where the sewage is finally disinfected, mixing of the treated and untreated liquid under the ship's conditions can be prevented, as the central area of the tank is characterized by a constant volume of liquid and minimal vertical displacements. This leads to a more uniform cleaning of the liquid to be treated in the electrochemical treatment unit and prevents the liquid from flowing out of the tank as well as the risk of exposing the electrodes. By making the purified liquid receiving tube so that its upper end protrudes above the liquid surface of the tank, the untreated liquid and foam are prevented from flowing into the treatment water tank and further out of the ship.

Preferably, the pneumatic vaahdopoistolaite comprises IL-majohdon, which is disposed along the electrochemical processing unit to the upper edge and provided with ilmanpoistorei1illä-side surfaces and ilmansyöttörei'illä the inside of the unit and the foam the receiving member, which is located in the center of the unit unit of the liquid surface of the ceiling above and connected to a blower, which is intended to develop a vacuum in the tank located in the separation unit, in the foam receiving member and in a space bounded by the surface of the liquid in the unit, the unit lid and the air line.

By positioning the air duct so that the air inlet and outlet holes are along the upper edge of the electrochemical treatment unit, a rational distribution of air along the entire upper edge of the electrochemical treatment unit is achieved. When this occurs, air currents force the circumferential portion of the foam electrochemical treatment unit toward its center, where the liquid and foam layer move as little as possible. When the device moves strongly laterally due to ship tilt, rocking, or vibration, the volume of purified water and foam in the center of the electrochemical treatment unit is virtually unchanged, which promotes rapid and efficient foam removal from the unit to the foam receiver. By placing the foam receiving member in the center of the container, the foam can be collected within the area of the electrochemical treatment where the liquid and foam move least vertically, which also facilitates the removal of foam from the electrochemical treatment unit. Placing the foam receiver above the upper limit of the liquid surface of the electrochemical treatment unit prevents the treated liquid from penetrating the foam receiver.

By means of a coupling joint between the foam receiving element and the fan which creates a vacuum in the tank located at the top of the solids separator in the foam receiving member itself and in a space bounded by the electrochemical treatment unit liquid surface, unit cover and air line through which air is drawn in through the air duct inlet holes to transfer foam from the electrochemical treatment unit to the solids separation unit, and ventilates the device by a single device, i.e. a fan, this leads to both a simpler device structure and simpler joints between its processing units.

It is expedient for the vertical partitions to be arranged in a space bounded by the outside of the foam receiving member and the inside of the air duct, which partitions are intended to divide this space into parts. With such a structure, the air flows can be prevented from cutting with each other, so that they flow in a more rational way, whereby the foam in the electrochemical treatment unit also becomes more efficiently removed.

In addition, it is expedient for the vertical partitions to be arranged so that their lower edges are immersed in the liquid and their upper edges extend at least to the upper edge of the air duct. Such a partition structure prevents airflows from passing above or below the partitions, allowing airflows to flow under the best conditions, thus helping to force out the foam in the required direction.

74695 16

Preferably, the unit for separating solid constituents from the sewer comprises a seat inlet for the sewer, below the outlet hole of which a conical filter is arranged on the shaft, the side surface of which is folded in the direction of the filter tip. below the base, while coaxially with the shaft is placed a slight member which is a cylinder made of a flexible material and is located at a distance from the bottom surface of the filter that is greater than the largest particle size of the solids to be separated.

A shaft-mounted cone filter with a cover near the tip of the cone can evenly distribute the flows of treated liquid over the entire filter surface and prevent solids from accumulating near the center of rotation, where the centrifugal forces caused by the rotation of the cone filter are negligible. This makes it possible to reduce the rotation speed of the filter shaft, which is very important when using the filter in ship conditions. The even distribution of the sewage flows on the surface of the conical filter contributes to the efficiency of cleaning the filter surface and the liquid to be treated.

By placing the inlet line outlet hole above the tip of the filter cone, an even distribution of the liquid to be treated is provided over the entire surface of the cone filter, which promotes even contamination of the filter surface, which improves the efficiency of cleaning the contaminated liquid and the filter surface. By placing the conical filter so that its side surface is folded in the direction of the filter tip, downstream water flowing from outside the conical filter is prevented from penetrating the solids collection tank, i.e. separating solids with as little water as possible and enhancing the treatment of contaminated liquid. Such a side surface structure promotes the accumulation of solids near the bottom of the filter cone, which in turn improves the efficiency of cleaning the filter surface of the cone filter due to higher centrifugal forces on contaminants in the area near the bottom of the filter cone than at the cone tip.

74 695

A slight member coaxially mounted with the shaft to which the Cone Filter is attached prevents contaminants from adhering to the walls of the filter frame and from wearing these walls. Furthermore, it should be noted that the use of a mild member does not in any way prevent solids from penetrating the lower part of the solids separation unit, but it does prevent the repeated penetration of contaminants onto the filter surface due to the flexibility of the member itself.

Preferably, the side surface of the filter is folded at an obtuse angle. When the side surface has such a structure, a blind alley does not form in the conical filter, which increases the efficiency of cleaning the filter surface and improves the efficiency of the treatment of the contaminated liquid.

When the slight member is arranged so that its lower edge extends at least to the bottom surface of the conical filter, the protection of the walls of the filter frame against solids adhering thereto is improved, which prevents wear of the walls of the frame.

According a to another form of embodiment, it is appropriate that the separated liquid vastaanottosuppiloon is arranged a ring-shaped tube along the hopper kartiosuodattimen bottom side the top edge, wherein the tube has holes in the filter inside of the side surface of the pipe, wherein the pipe is a pressure regulator coupled to the fluid source, which is intended to reduce the force with which the contaminants adhere to the filter surface of the filter. In this case, it is possible to apply a pressurized liquid or gaseous anti-adhesive medium inside the filter surface, which by acting on the layers on the filter surface reduces their adhesion to said surface and thus contributes to better cleaning of the filter surface and more efficient use of centrifugal forces during filter cleaning. The holes in the tube through which the medium is applied to the inner surface of the filter are arranged so that the jets of anti-adhesive medium coming from them overlap on the entire inner side of the filter surface of the conical filter. By applying a pressurized medium by means of a pressure regulator, which reduces the adhesion of contaminants to the filter surface of the filter, the removal of contaminants from the internal filter surface is promoted, which in turn prevents contaminants from passing from the filter surface to the treated liquid.

In the above-mentioned embodiment, it is further expedient that the holes in the annular tube expand towards the outer wall of the tube. This structure takes full advantage of the dynamics of the effluent jets of the medium, which reduces the adhesion of contaminants to the filter surface.

In this case, it is also advantageous for the holes in the annular tube to be provided with conically expanding nozzles. Although the structure is then slightly more complex, the dynamics of the jets discharging from the nozzles of the medium, which reduces the adhesion of impurities to the filter surface, can be used even more completely.

The invention will now be described in more detail by means of practical embodiments thereof and with reference to the accompanying drawings, in which: Figure 1 shows a flow chart showing a sewage treatment method according to the invention; Fig. 2 shows a block diagram of an electrochemical treatment unit showing the locations of the liquid and the foam layer during strong branches of the device according to the invention; Fig. 3 shows graphically the hydraulic resistances of the filter surfaces in relation to the degrees of clogging of the surfaces according to the invention; Fig. 4 shows a block diagram of an apparatus according to the invention for carrying out a sewage treatment method; Fig. 5 is a top view of the subject of Fig. 4; Fig. 6 shows an overview of the subject of Fig. 4; Fig. 7 shows the electrochemical treatment unit of Figs. 4, 5 and 6 in cross-section and on a larger scale; Fig. 8 is a top view of the subject of Fig. 7; Fig. 9 is a cross-sectional view taken along line IX-IX in Fig. 7; Fig. 10 is a cross-sectional view on a larger scale of another embodiment of the electrochemical treatment unit of Figs. 4, 5 and 6; Fig. 11 shows a cross-sectional view taken along line XI-XI in Fig. 10; Fig. 12 shows a cross-sectional view on a larger scale of a different embodiment of the electrochemical treatment unit according to the invention according to Figs. 4, 5 and 6; Fig. 13 is a cross-sectional view taken along line XIII-XIII of Fig. 5 on a larger scale; Fig. 14 shows an axonometric view of the air duct of Figs. 4, 5 and 6 on a larger scale (cubic shape); Fig. 15 shows the same subject as Fig. 14 (round shape); Fig. 16 shows the same subject as Fig. 14 and in which the electrochemical treatment unit has a cylindrical shape; Fig. 17 shows a cross-sectional view on a larger scale of the device according to the invention shown in Figs. 4 and 6, which separates solids from sewage and on which a Cone Filter is mounted; Fig. 18 shows on a larger scale a top view of the annular tube according to the invention shown in Fig. 17; Fig. 19 is a cross-sectional view taken along line XIX-XIX of Fig. 18; Fig. 20 shows a view of unit D of Fig. 19; and Fig. 21 shows a graphical view of the operation of the device according to the invention shown in Figs. 4, 5 and 6.

The diagram in Figure 1 illustrates a sewage treatment method. The treatment of the contaminated liquid is carried out in several successive steps, the first step being to filter the sewage 1 through a conical filter surface 2, the solids 3 being separated from the sewage liquid 1 and collecting in the lower part 4 separating the solids 3 from the sewage 1 and then disposed of while the purified sewage 5 is collected and leveled with respect to the volumetric load and physicochemical composition in the tank 6. The leveled sewage 7 undergoes electrochemical treatment in the electrochemical treatment unit 8, during which 74695 20 hydrogen bubbles and disinfection of sewage.

Depending on the chloride content, electrochemical disinfection of the sewage can be performed with chlorine (high chloride content), hydrogen peroxide and ozone (low chloride content). When this happens, the amounts of chlorine, hydrogen peroxide and ozone formed in the electrolysis of the sewage at different chloride concentrations are likely to change, whereby the total amount of said disinfectants in the treated sewage is kept the same.

The electrochemical treatment is carried out at a flow rate of smoothed sewage 7 sufficient to form a foam layer 9. During this process in the foam layer 9, the vacuum provided by the fan 10 in the unit 4 separating the solids 3 from the sewage 1 and thus in the electrochemical treatment unit 8 is connected to it, is formed without counter-currents 11, forcing the foam layer 9 from the peripheral areas towards its central part, indicated by the broken rectangle in the diagram of Figure 1, from which the foam suspension particles 12 are fed to a unit 4 separating solids 3 from sewage. The impurities 12 are then mixed with the solids 3 separated from the sewage 1 in the unit 4, and a mixture of these 13 is directed from the unit 4 which separates the solids 3 from the sewage 1 for disposal or use. The treated water 14 is directed to an area below the center of the foam layer 9, indicated by the rupture layer in the diagram, from where it is removed to a collection tank for later use or removal overboard.

By forming in the foam layer 9 during electrochemical treatment without countercurrents 11 forcing the foam layer 9 from the peripheral areas towards its center and the treated water 14 below the center of the foam layer 9, it is possible to collect foam and treated water 14 inside the zone where they are exposed to the smallest and their volume practically does not change when the electrochemical handling unit 8 moves strongly laterally as the ship tilts and swings. This is illustrated by a block diagram of the electrochemical treatment unit 8 (Fig. 2), which shows the positions of the liquid and the foam layer 9 during strong lateral movements of the device.

As can be seen from the diagram, during the sharp tilting of the electrochemical treatment unit 8, the boundary between the foam layer 9 and the water in the unit 8 can extend, for example, along lines A or B. In this case, the levels of water and foam layer 9 remain unchanged only in the middle part of the foam layer 9 and at point C of the water mass near it, and therefore the volumes of foam and water near point C also remain unchanged. Thus, it seems appropriate to force the foam and treated water to an area close to the center of the foam layer 9 when using the sewage treatment method described above in a ship designed for ship operation, i.e. under conditions caused by continuous ship vibration, heeling and rocking.

The sewage 1 (Fig. 1) is fed to the conical filtration surface 2 near its peak, which provides the best distribution of the sewage 1 to the entire filtration surface 2. This in turn results in efficient separation of solids 3 from the sewage 1 and a steady and gradually downward load on the filtration surface 2. The solids 3 accumulated on the filter surface 2 are removed therefrom by centrifugal forces caused by the rotation of the conical filter surface 2 and the effect of the medium 15 on them, which reduces the adhesion of the solids 3 to the filter surface 2 and is applied to the inside of the filter surface 2 opposite the side.

The supply of a medium 15 reducing the adhesion of the impurities to the filter surface 3 to the solids 3 which have accumulated on the filter surface 2 contributes to the cleaning of the filter surface 2, as it causes the impurities remaining on the filter surface 2 to loosen, melt and decompose. Since this medium 15 is supplied with pressure, impurities do not penetrate inside the filtration surface 2, which in turn prevents them from penetrating into the sewage 5 separated from the filtration surface 2. The pressure at which the medium 15, which reduces the adhesion of the contaminant to the filtration surface 2, is applied to the surface over a wide range and is highly dependent on a number of factors, the most important of which are: the state of the adhesion reducing medium 15, which may be gaseous or liquid or a mixture of liquid and gas; the temperature of the medium used; the nature of the deposits on the filter surface 2, etc.

The most preferred pressure of the liquid medium 15 is apparently 1-2 air-5 5 rings (10 Pa-2x10 Pa) and the gas medium 3-5 air-5 5 rings (3x10 Pa-5x10 Pa) and the liquid-gas mixture 2.5-3 air, respectively. -5 5 perimeters (2.5x10 Pa-3x10 Pa). It should be noted that the application of a medium to reduce the adhesion of contaminants to the filter surface 2 has a beneficial effect on the centrifugal forces which are the main means of removing contaminants from the filter surface 2. Once the adhesion of contaminants to the filter surface is reduced, they can be easily removed by either than the anti-adhesion medium 15 or later.

The medium 15 reducing the adhesion of impurities to the filter surface 2 is used only when 50-60% of the total area of the filter surface 2 is blocked. This limit is determined by the increase in the hydraulic resistance of the filter surface 2 as a result of large contaminants (paper, cotton, etc.) clogging the filter surface. The increase in the hydraulic resistance of the filter surface, which is proportional to its degree of clogging, has an exponential nature, as shown in Figure 2 graphically. In this diagram, the values of the hydraulic resistance of the contaminated filter surface 2 are plotted on the Y-axis without taking into account the hydraulic resistance of the clean filter surface 2. The values of the degree of clogging of the filter surface 2 are marked on the X-axis as a percentage of the total area of the filter surface 2. It follows from this diagram that when a surface is 50-60% covered, its hydral resistance is in the best range. When the values exceed the above, a clear increase in hydraulic resistance is observed, which causes a greater penetration of the liquid part of the sewage 1 into the unit 4 (Fig. 1), 74695 23 which separates the solids 3. When the adhesion reducing medium 15 is used when the contaminant covers the filtration surface below 50- 60%, this medium is consumed more and in addition the cleaning efficiency decreases due to time losses due to dense cleaning of the filter surface 2.

A variety of substances or mixtures thereof, both liquid and gaseous, can be used as a medium 15 to reduce the adhesion of contaminants to the filter surface 2, but hot water, a mixture of steam and water, a mixture of water and detergents such as surfactants, steam, hot air are preferred etc. The following are practical examples of cleaning the filter surface 2 from solids 3 by centrifugal forces and at the same time using various media 15 inside the filter surface 2, which reduce the adhesion of contaminants to the filter surface 2.

Example 1

As an example of embodiments of the sewage treatment method, consider the case where the filtration surface 2 having greasy and fibrous deposits is cleaned by centrifugal forces and hot water applied to the inside of the surface.

300 liters of sewage water 1 having a temperature of 20 ° C and containing an average of 650 mg / l of impurities were passed through the filter surface 2, of which an average of 0.1 g / l was greasy and 0.05 g / l was fibrous. Filter surface 2 stopped 27 g of greasy and 12 g of fibrous contamination. The cleaning of the filter surface 2 was performed as the surface rotated at a speed of 1000 rpm, and 60 liters of water having a temperature of 50 ° C and a pressure of 1 atmosphere (10 Pa) were fed inside.

When hot water at 50 ° C was used to wash the filtration surface, it was found that the grease contaminant adhered to the fiber contaminant, forming agglomerations that could be easily removed by centrifugal forces. Eleven experiments were performed in which the filter surface 2 was washed with hot water, and in the same number of experiments only centrifugal force was used. The experimental data are given in the following table, which shows that the efficiency of filter surface 2 cleaning when the combined effect of centrifugal forces and hot water on contaminants is increased, because the efficiency of filtration surface 2 centrifugal cleaning is improved by reducing the adhesion forces of contaminants and filtration. between surface 2 when the former are exposed to hot water. It is expedient to use hot water with a temperature of not more than 50 ° C to clean the filter surface 2 in large passenger ships with plenty of water of this temperature for the needs of the crew and passengers.

Example 2

As another embodiment of the method, consider the case where the filter surface 2 is cleaned by centrifugal forces and hot water having a temperature higher than the melting temperature of the fat contamination of the filter surface 2 is applied to its inner side.

Removal of grease and fiber contamination from the filtration surface only by centrifugal forces and with the help of these and at the same time hot water with which the filtration surface is washed.

No. Centrifugal cleaning of the filter surface- The weight of the filter impurities after stopping on the filter surface, the weight of the impurities remaining on the filter surface when the surface is cleaned- the weight of the impurities on the filter surface and washing with hot water__

Fat Fiber Fat Fiber Fat Fiber _3_2_2_2_2_2__ -3 1 27 12 0.5 1 Fat inclusions 10 -3 2 20 8 0.3 0.6 not visible to the eye. 2x10 -3 3 28 4 0.8 0.4 When removing 1x10 -3 4 15 10 0.1 0.9 fat solvent 5x10 5 17 5 0.09 0.1 washing occurred 1x10 3 -3 6 23 14 0.4 0.12 only minor 6x10 -3 7 12 9 0.8 0.08 traces of grease 1x10 -3 8 16 12 0.25 0.13 of contamination 1x10 9 22 7 0.4 0.2 8χ1θ “3 10 21 9 0 , 18 0.12 1x5.10 ~ 3 11 13 4 0.6 0.26 4x10 ~ 3 25 74 695

300 liters of sewage water with a temperature of 20 ° C and an average temperature of 30 ° C were passed through the filter surface. 650 mg / l of impurities, of which on average 0.1 g / l was fat contamination and 0.05 g / l fiber contamination. The filter surface 2 stopped 26 g of grease contamination and 13 g of fiber contamination. The filter surface 2 was cleaned as it rotated at a speed of 1000 rpm, and hot water having a temperature of 70 ° C exceeding the melting temperature of the grease pollution and a pressure of 1 atmosphere (10 Pa) were fed inside. Achieving the same degree of cleaning of the filter surface 2 as in Example 1 requires much less hot water, a total of 36 l, i. 24 1 less than at a water temperature of 50 ° C. Thus, by using a "hot" embodiment of the method, hot wash water can be saved and the method can be used in small vessels with limited hot water supplies.

Example 3

Another embodiment of the method is illustrated by the example of cleaning a filter surface contaminated with fat and fibrous layers by centrifugal forces and applying a mixture of steam and water inside it. 300 liters of sewage water having a temperature of 20 ° C and containing an average of 650 mg / l of impurities were passed through the filter surface 2. 0.1 g / l was fat contamination and 0.05 g / l fiber contamination. The filter surface 2 stopped 24 g of grease contamination and 12 g of fiber contamination. The cleaning of the filter surface 2 was performed as it rotated at a speed of 1000 rpm, and a mixture of steam and water was fed inside it at a pressure of 2.5 atmospheres (2.5 x 10 6 Pa). When the steam temperature was 127 ° C, the mixing ratio of steam and water was 2 kg of steam and 0.8 kg of water. 21 l of water were needed for washing. This embodiment of the method is particularly suitable for ships with a central steam supply system.

Example 4

Another embodiment of the method is illustrated by the example of cleaning a filtration surface contaminated with fat and fibrous deposits by centrifugal forces and applying a mixture of steam and water inside it.

The same amount of sewage was passed through the filter surface 2 as in Example 3, which had the same amount of contamination. In this case, the filtration surface stopped 28 g of grease contamination and 10 g of fiber contamination. The filter surface 2 was cleaned as it rotated at 1000 rpm, and a mixture of steam and water at a pressure of 3 atmospheres (3x10 4 Pa) was fed inside, the steam temperature being 134 ° C. The mixing ratio of steam and water was 1 kg of steam and 0.6 kg of water. 16 l of water were needed for washing.

As the temperature and pressure of the steam used were higher, less water was needed to clean the filter surface 2, whereby the water content of the solids 3 separated from the sewage water 1 to the filter surface 2 also decreased.

Example 5

Another embodiment of the method is illustrated by the example of cleaning a filtration surface contaminated with grease and fiber contaminants by centrifugal forces and feeding hot water to it with added detergent. 300 l of sewage water having a temperature of 20 ° C and containing an average of 300 l of water were passed through the filter surface in approximately the same manner as in the previous examples. 650 mg / l of impurities, of which on average 0.1 g / l was fat contamination and 0.05 g / l fiber contamination. The filtration surface stopped 27 g of grease contamination and 12 g of fiber contamination. Cleaning of the filter surface 2 was performed as it rotated at 1000 rpm, and hot water at a temperature of 50 ° C and a pressure of 1 atmosphere (10b Pa) to which disodium monoalkyl sulfosuccinate was added at a concentration of 0.5% was fed inside the surface.

To achieve the same degree of cleaning of the filter surface 2 as in Example 1, much less hot water was required, a total of 20 l, i. 40 l less than when using only hot water at 50 ° C.

The embodiment described above can well be used in small vessels with limited hot water, in which case the sewage passed through the filtration surface must be further treated and purified.

It should be noted that other surfactants can also be used as detergents.

Example 6

Another embodiment of the method is illustrated by the example of 74695 27 in which a filtration surface contaminated with fat and fibrous deposits was cleaned by centrifugal forces and hot water to which detergent had been added was introduced into it. The conditions for both sewage treatment and filtration surface cleaning were the same as in Example 4, but the water temperature was 70 ° C. In order to achieve the same degree of cleaning of the filter surface 2 as in Example 4, only a total of 14 l of water was needed, i.e. less than in the previous case. Thus, when there is limited water in the vessel, it is recommended to use this embodiment of the method to raise the water temperature.

Example 7

Another embodiment of the method is illustrated by the example of cleaning a filter surface contaminated with fat and fibrous deposits by centrifugal forces combined with steam applied to the inside of the surface.

As in the previous examples, 300 liters of sewage water with a temperature of 20 ° C and an average temperature were passed through the filter surface. 650 mg / l of impurities, of which on average 0.1 g / l was fat contamination and average. 0.05 g / l fiber contamination. The filtration surface stopped 24 g of grease and 13 g of fiber contamination. The cleaning of the filter surface 2 was performed as it rotated at a speed of 1000 rpm, and steam at a temperature of 120 ° C and a pressure of 2 atmospheres were applied to the inside. To achieve the same degree of purification of the filter surface 2 as in the previous examples, only 2.8 l of water would penetrate as a result of the condensation of steam into the impurities removed from the filter surface. When the impurities were further treated, e.g. during the heat treatment, the lower water content of the impurities, which is achieved by using steam to clean the filtration surface, makes it possible to substantially reduce the fuel consumed by the heat treatment. It is desirable to use this alternative embodiment of the method on ships with steam generating sources. An increase in the temperature of the steam as well as an increase in the pressure at which the steam is fed to the filter surface 2 leads to a better cleaning efficiency of the filter surface, but the choice of these parameters must be properly adapted to technical possibilities and the nature of deposits on the filter surface.

28

Example 8 7 4 6 9 5

To give an example of another embodiment of the method, consider the case of cleaning a filter surface contaminated with grease and fiber deposits by centrifugal forces combined with hot air applied to the inside of the surface. As in the previous examples, 300 liters of sewage water having a temperature of 20 ° C and containing an average were passed through the filter surface. 650 mg / l of impurities, of which on average 0.1 g / l was fat contamination and average. 0.05 g / l fiber contamination. The filtration surface stopped 24 g of grease and 13 g of fiber contamination. The cleaning of the filter surface 2 was performed as it rotated at a speed of 1000 rpm and hot air with a temperature of 250 ° C and a pressure of 2 atmospheres (2x10 Pa) was fed to the inside of the surface.

To achieve the same degree of purification of the filter surface 2 as in the previous examples, the water content of impurities removed from the filter surface was reduced by 20% (initial impurity water content was 92-98%) by further treating the impurities, e.g. . It is desirable to use this embodiment of the method whenever a waste incinerator for solids is available near the sewage treatment plant, which greatly facilitates the transport of solids to the incinerator, and also when the ship has a hot gas source, e.g., oil-carrying vessels with inert gas generators.

From the embodiments of the invention described above, those skilled in the art will appreciate that the objects of the invention can be easily achieved within the scope of the appended claims. However, the invention is not intended to be limited to any of these described embodiments, but is provided solely to illustrate the invention. In the implementation of the method, it is also quite obvious that other insignificant modifications and alterations may be possible in the operating conditions, parameters and various means without deviating substantially from the idea of the invention.

For clarity, previous embodiments of the invention have been described using special vocabulary, but it is to be understood that each designation 74695 29 is intended to cover all available, equivalent parts which function in the same manner and are used to achieve the same objects.

The apparatus for carrying out the described method of purifying sewage comprises a unit 4 (Fig. 4) which separates the solids 3 from the sewage 1 and which is connected by a pipeline 16 to a tank 6. which collects and levels the solids separated by the unit 4, an electrochemical treatment unit 8 connected by a pressure pipeline 17 to a sewage collection and equalization tank 6.

Between this tank 6 and the leveled sewage treatment unit 8 there is a pump 18 which pumps the leveled sewage from the sewage collection and leveling tank 6 to the leveled electrochemical treatment unit 8. The leveled electrochemical treatment unit 8 is connected to the tank 20 by a pipeline water 14. This tank 20 is connected by a pipeline 21 to a pump which pumps the treated water overboard.

The sewage solids separation unit 4 is connected by a pipeline 23 to a pump 24 which removes the mixture of solids 3 and electrochemically removed impurities 12 from the sewage solids separation unit 4.

The pump 24 is connected to the sewage collection and equalization tank 6 separated by pipeline 23 and pipelines 25 and 26 to the electrochemical treatment unit 8 of piped water 23, 25 and pipelines 27, 28, 29 and 30, and by pipelines 23, 25, 27 and pipeline 31 to a sewage solids separation unit 4.

Valves 32 and 33 are used to dry the electrochemical treatment unit 8 of the smoothed sewage; by means of the valve 34 the sewage collection and leveling tank 6 is dried and by means of the valve 35 the sewage solids separation unit 4 is dried. If necessary, a crusher 36 is used between the sewage solids separation unit 4 and the pump 24. The crusher 36 is switched on and off by means of a valve 37. The sewage collection and leveling tank 6 is provided with a circulating pipe 38 for flushing out the deposits formed in the sewage collection and leveling tank and for controlling the speed at which the leveled sewage is fed to the electrochemical treatment unit 8 connected to the pipe 8. , which is located in the solids solids separation unit 4 and below the vacuum generated by the fan 10. The container 40 has a sleeve 41, the lower end of which is immersed in a liquid which is continuously in the solids separation unit 4 of the sewage water and penetrates here during the solids separation and together with the contaminant which is separated in the electrochemical treatment. In addition, the tank 40 has a hole 42 through which the sewage solids separation unit 4 is ventilated. Inside the sewage solids separation unit 4 there is an inlet sleeve 43 with a cone filter 45 mounted on the shaft 44 below the outlet hole. Under the bottom of the cone filter 45 there is a receiving funnel 46 cone filter actuators).

Sewage solids separation unit 4 (Figs. 5 and 6), leveled sewage electrochemical treatment unit 8, sewage collection and leveling tank 6 (Fig. 5), tank 20 (Figs. 5 and 6) containing treated liquid are small in size and are installed on the same platform 47. In the middle of the electrochemical treatment unit 8 of the leveled sewage (Fig. 5) there is a hole 48 through which the air intake takes place. There may be more such air intake holes 48. Sleeve 43 (Figures 5 and 6) connects the device to a ship's sewage source (not shown). The mains unit 49 is on top of the housing of the sewage solids separation unit. Electrochemical treatment unit for smoothed sewage: 8 are located on top of tanks 6 (Fig. 5) and 20 (Figs. 5 and 6). The sewage solids separation unit 4 is on the platform 47. Such an arrangement of the tanks 6 and 20 and the units 4 and 8 in the device has been found to be advantageous because it improves the rigidity of its structure and reduces the overall dimensions. An air-operated device 50 (Figures 4, 5 and 6) is mounted along the upper edge of the leveled electrochemical treatment unit 8 to remove the foam that develops in the leveled electrochemical treatment unit 8. The fan 10 is driven by an electric motor 51 (Figure 5) pump 24 driven by an electric motor 52, the drive 18 is driven by an electric motor 53 and a pump 22 by an electric motor 54.

74695

The sewage solids separation unit 4, the sewage collection and leveling tank 6 and the smoothed sewage electrochemical treatment unit 8 are provided with bottoms with a slope towards the respective pipelines 31 (Figs. 4 and 5), 26, 29 and 30.

The smoothed sewage electrochemical treatment unit 8 (Fig. 7) is made in the form of a divided tank 55 divided by partitions 56, 57 and 58 (Fig. 8). In the center of the divided tank 55 (Fig. 7) is a treated liquid receiving pipe 59 which is vertical and hydraulically connected to a liquid discharge means 60 in the form of a discharge pipe and to a compartment 61 of the tank 55 where the final disinfection of the sewage takes place. The upper end of the treated liquid receiving tube 59 is located so as to protrude above the liquid surface of the container 55.

One compartment 62 contains active aluminum electrodes 63 and one compartment 64 contains inert graphite electrodes 65 and compartment 61 contains inert graphite electrodes 66. The electrodes 63, 65 and 66 are connected in parallel with the mains device 49 (Figures 5 and 6) so that when there is a break in the electrode supply circuit or electrode is damaged in one of the compartments of the electrochemical treatment unit 8, current is maintained between the electrodes of the other compartments. In addition, an automatic reversal of the polarity of the electrodes is used to prevent the electrodes from being passivated by the oxides and insoluble compounds formed in the electrolysis. Compartment 67 (Figure 7) is for removing gas bubbles and coagulated colloidal contaminants from sewage.

The air-operated device 50 includes an air duct 68, located along the upper edge of the electrochemical unit 8 of the smoothed sewage and having air outlet holes 69 on the surfaces of the air duct 68 facing the inside of the electrochemical treatment unit 8. In order for the air to escape evenly from the holes 69, the upper part of the air duct 68 is provided with closed walls 70. The walls of the air duct 68 also have a hole 48 with a sleeve 71 for the intake of outdoor air. Below the sleeve 71 there is a partition 72 in the air duct 68 (Fig. 8) by means of which the air is evenly distributed between the two halves of the air duct 68. Mounted on the corners 74695 32 of the air duct 68 are dividers 73 intended to reduce the turbulence of the air currents and to eliminate stagnation areas at the corners of the air duct 68. Behind each vent hole 69 are cut-off portions 74 which cut and direct a portion of the air toward the center of the space bounded by the air line 68, the surface of the liquid in the electrochemical treatment unit 8, and the lid of this unit (not shown). The air line 68 has a septum 75 on the opposite side of the sleeve 71 which prevents air counterflows in the air line 68. The partitions 72 and 75 also prevent the treated liquid from overflowing as the device tilts from one half of the air line 68 to another.

Mounted in the center of the electrochemical treatment unit 8 above the upper limit of its liquid surface is a foam receiver 76 (Fig. 7) connected to a fan 10 (Figs. 4, 5 and 6) which creates a vacuum in the tank 40 in the solids separation unit 4. in the receiver 76 (Fig. 7) and in a space bounded by the liquid surface of the electrochemical treatment unit 8, the lid of this unit and the air line 68. Foam containing suspension impurities is fed from the foam receiver 76 to the line 77 and further to the line 39 (Figs. 6) through a tank 40, from where it is fed to a sewage solids separation unit 4, where the foam mixes with the solids and from which it is removed by means of a pump 24. In the space between the outer surface of the foam receiver 87 (Fig. 8) and the inner surface of the air duct 68, vertical partitions 78 are installed, which divide this space into compartments and are located so that their lower edges are immersed in the liquid in the leveled sewage electrochemical treatment unit 8. while their upper edges extend at least to the level of the upper edge of the air duct 68 and to the cover of the electrochemical unit 8 of the smoothed sewage. These partitions 78 may equally well be located above the upper edge of the air duct 68 and may extend to the cover of the leveled sewage electrochemical treatment unit 8. Because the partitions 78 divide the space formed by the air duct and the surface of the broth in the electrochemical treatment unit 8 of the leveled sewage, they prevent mixing of the air streams coming from each half of the air duct 68 towards the center of this space. Said partitions 78 further assist in transferring foam to the receiver 76. To prevent airflows above or below the partitions 78, their lower edge is immersed in the liquid in the leveled sewage electrochemical treatment unit 8, while their upper edge is at least at the upper edge of the air line 68 the lid of the sewage electrochemical treatment unit 8 contacts the upper edge of the air line 68). If the deck of the leveled electrochemical treatment unit 8 has a clearance between the cover and the upper edge of the air duct 68, the upper edge of the partitions 78 must be in contact with the cover of the leveling electrochemical treatment unit 8.

The electrochemical treatment unit 8 is provided with a pressure line 17 (Figures 5 and 6) for supplying leveled sewage to the unit. The removal of treated and purified sewage from the compartment 61 (Fig. 7) is provided by a double bottom 79 (Figs. 7 and 9), a hole 80 in the treated liquid receiving tube 59, a liquid outlet means 60 made as a discharge pipe, and a pipeline 19 (Fig. 7). 5) to a tank 20 containing treated sewage. The connection of the compartment 6 to the treated liquid receiving pipe can be made by a pipe 81 (Figures 10 and 11). The treated liquid discharge means 60 may be located inside the treated liquid receiving tube 59, as shown in Fig. 12. In this case, the sewage is removed through the bottom of the electrochemical treatment unit 8.

Fig. 13 shows the connection of the foam receiver 76 in the middle of the electrochemical treatment unit 8 above the upper limit of the surface of this liquid, the fan 10 which creates a vacuum in the sewage solids separation unit tank 40, the foam receiver 76 and the space bounded by the liquid surface of the electrochemical treatment unit 8 , the lid of this unit 8 and the air line 68. The container 40 has a partition 82 which separates the foam from the air.

Figures 14, 15 and 16 show axonometric views of various embodiments of overhead line 68. The air duct 74695 34 to 68 of Fig. 14 is made in the shape of a hexagon (plan view), the air duct of Fig. 15 is circumferential and the hexagon of Fig. 16 is shaped, the electrochemical treatment unit 8 being cylindrical.

Fig. 17 shows a solids separation unit 4 including a cone filter 45. The side surfaces 83 of the cone filter 45 face rearwardly towards its apex and the filter is mounted on the shaft 44 below the outlet hole of the solids separation unit 4 sleeve 43. The side surface 83 of the cone filter 45 is made in the form of a uniformly braided mesh. The cover 84 is mounted on the shaft 44 at the apex of the conical filter 45. Below the bottom of the conical filter 45 is a separated sewage receiving funnel 46 and the outlet sleeve 16 is connected to the tank 6, while a threshold 85 made of a cylindrical resilient material, e.g. rubber, is mounted coaxially with the shaft 44 at a distance from the bottom of the conical filter 45. exceeds the maximum size of the solids separated.

The side surface 83 of the cone filter 45 is at a backward obtuse angle. The threshold 85 is located so that its lower edge extends at least to the level of the bottom of the conical filter 45, but it can be placed just as well below this level.

A ring tube 86 with holes 87 (Figures 18 and 19) in the surface of the tube facing the inside of the cone filter 45 (Figure 17) is mounted in the treated sewage receiving hopper 46 along its upper edge towards the bottom of the cone of the filter 45. The annular tube 86 is connected by a pressure regulator (not shown) to the source of the medium (not shown) which reduces the adhesion of contaminants to the filter surface of the filter 45.

The holes 87 in the annular tube 86 (Fig. 19) may be made to enlarge toward the outer wall of the tube, or they may be provided with conically expanding nozzles 88 (Fig. 20).

The pipe 16 (Fig. 17) of the solids separation unit 4 is provided with a network-equipped emergency overflow sleeve 89, which keeps the device in working order if the Cone Filter 45 strikes. For eye inspection of the side surface 83 of the cone filter 45, there is an inspection hole 90.

The sewage treatment plant works as follows. The sewer 74695 35 from the sanitary fittings of the ship is fed through a sleeve 43 (Fig. 4) to a cone filter 45 which removes large contaminants (paper, cotton, food waste, etc.) from the sewage. The partially purified sewage water is introduced into the receiving hopper 45 and further through the pipe 16 to the separated sewage collection and leveling tank 6.

The smoothed sewage is collected in a tank 6. When the sewage reaches a certain level, a transfer device (not shown) in the tank 6 starts to operate, after which the supply of power begins to the electrodes 63, 65, 66 (Fig. 7) and the fan 10 (Fig. 4). The pump 18, which pumps the smoothed sewage via the pipeline 17 to the electrochemical treatment unit 8, starts simultaneously. Some of the liquid is returned via line 38 to the sewage collection and leveling tank 6, whereby it flushes out the deposits accumulated in the tank 6, mixes the sewage therein to smooth this physicochemical composition and ensures 38 through.

Through the pipeline 17 (Fig. 8), sewage water is fed to the lower part of the compartment 62 (Fig. 7) of the electrochemical treatment unit 8. Compartment 62 contains active aluminum electrodes 63 which are in parallel and through the clearances of which the sewage to be treated is circulated. When this occurs, the colloidal impurities in the sewage water coagulate under the influence of an electric field and under the influence of aluminum ions which enter the solution due to this effect. As a result, hydrogen is released at the electrodes acting as cathodes. This released hydrogen forms gaseous miniature bubbles which, on coagulated and suspended, fine impurities, carry on the surface of the liquid, forming a foam on the surface of the treated liquid. The liquid passing the partition 56 is then fed from top to bottom into a compartment 64 which contains a parallel array of inert graphite electrodes 65. As a current passes through the inert graphite electrodes 65, these electrodes also generate hydrogen, which removes contaminants from the flotation fluid. This process involves the release of the purifying substances, i.e. chlorine 74695 36 hydrogen peroxide and ozone, at the anodes. The liquid treated from the lower part of the compartment 64 flows under the partition 58 (Figs. 8, 9) to the compartment 67 (Fig. 7), where the impurities containing the smallest hydrogen bubbles and accompanying the liquid flowing down from the compartment 64 are removed from the liquid to be treated. From compartment 64, fluid flows to compartment 61, which contains graphite electrodes 66 arranged in parallel. Other contaminants remaining in the treated liquid are finally removed in compartment 61. The final treated liquid is fed from the bottom of compartment 61 either below the double bottom 79 (Figs. 7, 9, 12) or through line 81 (Figs. 10, 11) to the treated liquid receiving tube 59 (Fig. 7). , from which, through a treated liquid discharge means 60 in the form of a tube, the liquid is introduced via a pipeline 19 (Figures 4, 5, 6) to a container 20 containing the treated liquid and from there is directed by a pump 22 through a pipeline 21 either for further use or over side.

The removal of the treated water from the electrochemical treatment unit 8 can be performed through a means 60 (Fig. 12) made in the form of a tube and placed inside the treated liquid receiving tube 59. In this case, the sewage is removed through the bottom of the electrochemical treatment unit 8. Such an arrangement also makes it possible to improve the manufacturing properties of the electrochemical treatment unit 8.

After the electrochemical treatment of the sewage water, the coagulated and fine impurities carried by the hydrogen bubbles released in the electrolysis on the surface of the liquid to be treated form a foam layer 9 on the surface of the liquid (Figs. 1, 8). To remove foam during electrochemical treatment of sewage, the fan 10 (Figs. 4, 5, 6) creates a vacuum in the tank 40 (Figs. 4, 5, 6, 13) which is conveyed by pipelines 77 (Fig. 13) to the foam receiver 76 and to a space limited by electrochemical treatment. the liquid surface of the unit 8, the cover of this unit 8 and the air duct 68. As a result of this vacuum, outside air penetrates through the sleeve 71 and through the hole 48 into the air duct 68, from where it passes through the holes 69 to the foam receiver 47.

74695

Trapped by the outside air currents, the foam enters the foam receiver 76 via line 77 to tank 40 in solids separation unit 4. This is followed by foam loss resulting from sudden changes in the velocity and direction of the foam and air in tube 77 and tank 40. The suspension thus formed is passed through the sleeve 41 to the lower part of the solids separation unit 4, where it mixes with the solids separated from the sewage by the conical filter 45 (Figs. 4, 6, 17).

The air and hydrogen separated from the foam by the fan 10 are vented to the outside air. The septum 82 (Fig. 13) separates the liquid droplets carried by the air currents.

Solid contaminants in the sewage water remaining on the side surface 83 of the cone filter 45 (Fig. 17) are removed here by regularly rotating the cone filter 45 from the actuator (not shown). In order to distribute the sewage water more evenly to the side surface 83 of the cone filter 45, water is fed to the top of the filter 45 cone and the flat surface screen 84 also promotes the distribution of contaminants over the entire side surface 83. impurities from this surface.

In order to reduce the amount of water which, together with the impurities, penetrates the lower part of the solids separation unit 4, the side surface 83 is turned towards the top of the cone filter 45 at an obtuse angle down to stop the running water flowing along the side surface 83. As the load on the conical filter 45 suddenly increases, its inverted edge stops water that has not yet been filtered by the side surface 83. In addition, contaminants stopped by the inverted side surface 83 are subsequently easily removed from the surface during this cleaning due to the magnitude of the wrapping angle of this surface and the fact that the contaminants are sufficiently spaced from the axis of rotation of the conical filter 45.

The threshold 85 located in the solids separation unit 4 slows down the solids which bounce off the side surface during the filtration of the sewage and when the filtration surface of the conical filter 45 74695 38 is cleaned by centrifugal forces generated during its rotation. In addition, said threshold 85 prevents solids from adhering to the walls of the solids separation unit 4 and protects them from wear.

The side surface 83 of the cone filter 45 is cleaned automatically. After a predetermined amount of sewage has passed through the side surface 82, the level sensors (not shown) located in the sewage collection and leveling tank 6 actuate the shaft 44 power source. The Interval of the power supply operation is adjusted in advance with the time switch (not shown). Prior to rotation of the conical filter 45, a medium that reduces the adhesion of contaminants to the filter surface of the filter 45 is fed through the annular tube 86 to the inner surface of the filter. The supply of this medium is interrupted when the drive is stopped. The supply of the medium which reduces the adhesion of contaminants to the filtering surface of the conical filter 45 can be performed before the conical filter 45 has started to rotate and can be stopped at the moment when its drive is started.

A first method of feeding medium that reduces the adhesion of contaminants to the filter surface of the conical filter 45 is recommended for use in treating only black water, while a second method of feeding medium is recommended for treating all sewage generated on board.

When the sewage treatment device operates automatically, a predetermined pressure is applied to supply a medium to the inner surface of the conical filter 45 which reduces adhesion. However, if the filtration conditions are worse because very large or strongly adhering contaminants penetrate the side surface 83, the pressure of this medium can be considerably increased. The medium 15 (Fig. 17), which reduces the adhesion of contaminants to the side surface 83, is fed through holes 87 (Fig. 19) or nozzles 88 (Fig. 20) in the annular tube 86, so that the jets of medium from them overlap evenly over the entire inner surface of the conical filter 45. The holes 87 (Fig. 19) are made in the annular tube 86 so as to expand towards the outside of the tube and thus provide the best hydrodynamic conditions for the outflow of the medium which reduces the adhesion of contaminants to the data surface of the conical filter 45. This is also partly due to the use of said holes 87 and nozzles 88 (Fig. 20).

When performing periodic maintenance when the device is stopped or the faults are eliminated, the solids separation unit 4 (Fig. 4) has to be dried by the sewage electrochemical treatment unit 8 and the collection and leveling tank 6 by means of a pump 24. Said units and the tank can be dried both simultaneously and separately. When done simultaneously, valve 37 is closed, while valves 32, 33, 34 and 35 are opened. In separate drying, valve 37 is closed and the valve belonging to the unit is opened.

To facilitate the transport of solids in the piping system and to facilitate their disposal in a specially designed ship furnace (waste incinerator), the solids are decomposed by a crusher 36 (Figures 4, 5, 6).

In addition to transferring foam and removing hydrogen, the fan 10 ventilates the units and tanks while maintaining a low vacuum in the device and preventing bad odors from penetrating the ship's compartments.

The graphical diagram in Fig. 21 shows the performance data of the device obtained over 90 days and plots on the Y-axis the values of the concentrations of the suspending agents (C) and the biochemical oxygen demand (BOD,.), Whereby the coliform content in the untreated sewage water is 10 ^ -10 ^ pcs / 1 and in treated sewage 20 pcs / 1. Graph E shows the variation in the properties of the untreated sewage (curve G '- suspending agents and curve h1-bod5).

Graphic diagram F shows the properties of the sewage treated in the apparatus of the invention and shows that the concentrations of the suspending substances (curve G) and BOD (curve H) meet the 1973

D

requirements of the International Convention for the Prevention of Pollution from the Sea.

Thus, the proposed sewage treatment method and equipment can be used in many different applications on all types and categories of ships and provides rare efficient operation and treatment.

Claims (19)

1. A process for wastewater purification by treating it in several successive steps, wherein in the first stage solid constituents are separated from the liquid and collected, in the second stage the liquid water separated in the previous stage is homogenized with respect to the volume equalization and physical / chemical composition, the liquid homogenized in this way in the third step is subjected to an electrochemical treatment at a sufficient flow velocity (9) on the surface with subsequent separation of impurities from purified water (14). another - characterized in that - in the first step during the separation of the solid constituents (3), 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 is formed in the foam layer (9) directed against each other air streams (11) which drive the foam from the edge areas of the foam layer (9) towards its center, and are transmitted therein from in such manner to the first stage of separation of the solid constituents (3) from the west, that the foam is mixed with the solid constituents (3), and that - electrochemically purified water (to the zone located below the center of the foam layer (9)) 14) and is taken out of this zone. Process according to Claim 1, characterized in that, before mixing the foam with the foam, the solid constituents (3) are separated by filtration of the wastewater (1) through a conical filter surface (2) by passing the wastewater (1) in the direction thereof. tip, after which the solid constituents (3) collected at the filter surface (2) are removed by centrifugal forces and by the action of a medium (15) which is intended to reduce the adhesive force of the impurities at the filter surface (2), and under pressure on the inserts. then of the filter surface (2), to the outside of which the wastewater (1) is supplied. Method according to claim 2, characterized in that the adhesion-reducing medium (15) is applied after clogging 50-60% of the filter surface (2). 4. A process according to claim 2, characterized in that the adhesion-reducing medium (15) is hot water. 45 74695 Process according to claim 2, characterized in that the adhesion-reducing medium (15) is a mixture of meadow with water. 6. A process according to claim 2, characterized in that the adhesion reducing medium (15) is a mixture of water and detergent, for example surfactants. Process according to claim 2, characterized in that the adhesion-reducing medium (15) is made of meadow. 8. A method according to claim 2, characterized in that the adhesion-reducing medium (15) consists of hot air. An installation for carrying out the process according to claim 1, comprising a unit (4) for separating the solid constituents (3) from the wastewater (1), a container (4) connected by a pipe (16) 6) for collecting and homogenizing the wastewater (1), a unit (8) equipped with electrodes (63, 65, 66) for an electrochemical treatment, which is provided with means for entering and discharging wastewater and connected to the container ( 6) by a pressure pipe (17), characterized in that a container (40) under pressure is provided in the unit (4) for separating the solid components (3) from the waste water (1), which container is provided with a pipe plug (41), the lower end of which is immersed in the liquid, which is continuously located in the separating unit (4), the container (40) being connected by means of a pipe (39) to the unit (8) for the electric - the chemical treatment, which is provided with a pneumatic device (50) for breeding ownership of the foam formed during the electrochemical treatment. Installation according to claim 9, characterized in that the electrochemical treatment unit (8) is constructed in the form of a sectioned container (55) with a tube (59) arranged vertically in its center part, for receiving purified water and hydraulically connected to a means (60) for receiving purified water and to the section (61) of the container (55), the upper end of the purified water receiving tube (59) projecting above the liquid level in the container (55). Installation according to claim 9, characterized in that the pneumatic device (50) for removing the foam comprises an air conduit (68) arranged along the top of the electrochemical treatment unit (8) and provided with air outlet sheath (69), which are accommodated in the surfaces facing the interior of the unit (8) and with air intake housing (48), and one-foam receiving means (76) arranged in the center portion of the unit (8) above the upper boundary of the floor level in the unit (8) and connected to the bottle (10), which is intended to produce suppression in the container (40) arranged in the separating unit (4), in the foam receiving means (76) and in a space which is defined by The wiper surface of the unit (8), its cover and the air line (68). 12. Installation according to Claim 11, characterized in that vertical intermediate walls (78) are arranged in a space defined by the outside of the foam receiving means (76) and the inside of the air conduit (68), which are designed to divide spaces. in sections. Installation according to claim 12, characterized in that the vertical intermediate walls (78) are arranged so that their lower edges are lowered in the liquid and their upper edges extend at least to the top of the air line (68). Installation according to any of claims 9 - 13, characterized in that the unit (4) for separating the solid constituents (3) from the liquid in the wastewater (1) comprises an inlet pipe nozzle (43) for the wastewater ( 1), below whose outlet head, an axis (44) is arranged on a conical filter (45), the side surface of which (83) faces in the direction of the tip of the filter (45), at which a screen (84) is arranged the pS shaft (44), wherein a receiving funnel (46) provided with a discharge pipe nozzle (46) for the separated wastewater Sr is disposed beneath the base of the conical filter (45), while providing a skirt-shaped member coaxially with the shaft (44) (85) in the form of a cylinder of elastic material, which is separated from the base surface of the filter (45) by a spacing which is larger than the maximum particle size of the solid phase constituents to be separated. A device according to claim 14, characterized in that the side surface (83) of the filter (45) is folded at an obtuse angle. 16. A device as claimed in claim 14, characterized in that the skirt-shaped member (85) is arranged so that its lower edge extends at least to the base surface thereof.