RU2281256C1 - Method of fine cleaning of water - Google Patents

Abstract

FIELD: ecology; multi-stage methods of cleaning and decontamination of portable water; final cleaning and conditioning of tap water.

SUBSTANCE: proposed method includes preliminary filtration of water at first stage of micro-filtration through porous filter element made in form of tube from porous titanium or radiation-modified porous polyethylene at size of pores from 1 to 5 mcm in direction perpendicular to water flow; part of treated water is periodically discharged for use; after preliminary filtration, water flow rate is averaged to 15-20 l/h, after which is treated with ions of decontaminant; silver is used as contaminant; procedure is continued till concentration of silver reaches 0.1-0.0025 mg/l; second stage of micro-filtration is effected by means of porous filter element made from ceramics or cermet at size of popers of 0.2-0.4 mcm and then water is subjected to degassing.

EFFECT: low cost of process; possibility of performing ecologically pure technology of cleaning water.

6 cl, 2 ex

Description

The invention relates to the field of ecology, in particular to multistage methods for purifying and disinfecting drinking water in domestic conditions, and can be used to create installations for the purification and conditioning of tap water at drinking water supply facilities for individual and collective use, such as apartments, children's and medical facilities, and etc.

The ever-growing demand of the population for drinking water creates the problem of providing consumers with environmentally safe drinking water, in particular in Russia in accordance with GOST 2874-82 “Drinking water”, as well as sanitary rules and norms - SanPiN 21.4.559-2002. The quality of the tap water supplied to the consumer for drinking purposes sometimes does not meet the requirements of existing standards, in particular, the deterioration of most water supply networks contributes to this. To obtain environmentally safe and air-conditioned drinking water, the creation of low-cost methods for deep complex tertiary treatment of tap water immediately before it is supplied to the consumer is required.

Numerous methods are known for purifying drinking water before serving it using natural sorbents, such as coal, zeolite, shungite, hematite, quartz and others, as well as their various combinations (RU, patent No. 2074120, C 02 F 1/28, 1997 ., RU, patent No. 2100282, C 02 F 1/28, 1997, RU, patent No. 2174956, C 02 F 1/28, 1999 and others).

Common disadvantages of the known methods are the complexity of their use in everyday conditions due to the inability to control the change in the sorption capacity of the used sorbents to prevent “volley” emissions of contaminants and microorganisms accumulated by the sorbents, and, as a consequence, the need for periodic regeneration or replacement of sorbents, which significantly complicates and increases the cost of the post-treatment of drinking water, especially for individual users.

There are also known methods of treating drinking water before serving it using natural sorbents modified with ionic silver (RU, patent No. 2077494, C 02 F 1/28, 1997; RU, patent No. 2049053, C 01 B 31/08, 1995 g. and others). Known methods can improve the degree of purification and disinfection of drinking water, in particular, from organochlorine and microflora sensitive to ionic silver.

The disadvantages of the known methods are the complexity of the preparation of sorbents impregnated with silver, as well as the washing out of silver ions during water purification and their entrainment with a stream of purified water, which, on the one hand, leads to the need for periodic replacement of the sorbent, which increases the cost and complexity of water purification, and on the other - to increase the silver content in purified water, exceeding its maximum permissible concentration.

There is a comprehensive method for deep purification and conditioning of water, according to which the treated water is subjected to preliminary filtration, sorption processing and microfiltration on the filter elements with pore sizes of 0.5-10 microns. At the same time, numerous sorbents are used in the cleaning process, including the bactericidal sorbent - the silver form of activated carbon (WO 96/20139, C 02 F 9/00, 1996), which can be used.

The disadvantages of the known method, in particular for use in everyday life, are its complexity and high cost due to the use of numerous sorbents with an insufficiently high resource of work, which must be periodically replaced (or regenerated).

The closest in technical essence to the proposed one is a multi-stage method for deep water purification, according to which the treated water is subjected to preliminary filtration on a multilayer stainless steel mesh with a predominant mesh size of 50-80 μm, then the water is subsequently fed to microfiltration through porous propylene with a predominant pore size of 10 -20 microns, for sorption processing and final microfiltration, while before microfiltration and sorption processing periodically using a dispenser administered disinfecting agent containing diamminargenat ions. Preferably, the water is treated at a flow rate of 300-600 l / h (RU, patent No. 2188165, C 02 F 9/04, 2002).

The disadvantages of this method are its complexity and high cost, especially when used in a domestic environment. First of all, the method of obtaining a disinfecting agent with its subsequent multi-stage dosing into the treated water is quite complicated and time-consuming. In addition, the operation of the installation, which implements the known method, involves interruptions in operation - technological stops.

The objective of the invention is to obtain an inexpensive, reliable and environmentally friendly technology for treating drinking water in a domestic environment.

The technical result obtained from the use of the proposed method is to simplify and cheapen the production of drinking water with organoleptic properties in accordance with existing Russian and European standards, eliminating the need for periodic replacement and / or regeneration of filter elements for a long time (up to one of the year).

The problem is solved, and the technical result is achieved due to the fact that in the method of deep water purification, including its preliminary filtration, two-stage microfiltration through a porous filter element, ion treatment of the disinfecting agent, sorption treatment and supply of purified water to the consumer, preliminary filtration of the treated water is carried out on the first stage of microfiltration through a filter element made in the form of a tube of porous titanium or radiation-modified porosity polyethylene with a pore size of 1-5 microns, in the direction perpendicular to the movement of water, with periodic withdrawal of part of the treated water to the consumer in the direction of movement of water for use in technical needs, the water flow after preliminary filtration is averaged to 15-20 l / h s subsequent processing by saturation in a stream with ions of a disinfecting agent, which is used as silver, to ensure a silver concentration of 0.1-0.0025 mg / l, and then the water is subjected to sorption treatment in series, the second hundred ii microfiltration through a porous filtering element made of a ceramic or a cermet with a pore size of 0.2-0.4 micron, and degassing.

Preferably, the saturation of the treated water in the stream with silver ions is automatic, and the sorption treatment is carried out in at least one stage using activated carbon as a sorbent.

If necessary, sorption treatment is carried out in two or more stages, while activated carbon is used as a sorbent in the last stage, in particular, sorption treatment is carried out in three stages using zeolite, shungite and activated carbon as sorbents, respectively .

It is preferable to degass the purified water before supplying it to the consumer in natural conditions.

The set of features set forth in the claims characterizing the proposed method allows to simplify, reduce the cost and increase the reliability of obtaining drinking water in domestic conditions that meets existing Russian and European standards.

The preliminary filtration of the treated water by microfiltration through a filter element made in the form of a tube of porous titanium and radiation-modified porous polyethylene with a pore size of 1-5 μm, in the direction perpendicular to the movement of water, with periodic removal of part of the treated water in the direction of movement of water for use in technical needs, allows further purification of water without interrupting its flow. At the same time, at the first stage of microfiltration, mechanical and suspended contaminants, high molecular weight organics and colloidal particles can be removed at the same time, which gradually reduce the filtering ability of the tube with a porous wall, but with periodic removal of part of the treated water in the direction of water movement for use in technical needs, these contaminants are removed with this flow, the filter element is regenerated and its original filtering ability is restored without interrupting the flow pre-filtered water. Thus, the regeneration of the filter element in the first stage of microfiltration is carried out in a stream with simultaneous microfiltration of the treated water in the direction perpendicular to its movement, which is very important to ensure the continuous production of drinking water of the proper quality - without shutting down the regeneration.

The use of a tube with a porous wall at the first stage of microfiltration as a porous filter element allows you to periodically divide the treated water supplied into the inner channel of the tube with a porous wall into two streams, one of which passes microfiltration through the porous wall in the direction perpendicular to the movement of the treated water, and the other, continuing to move in the direction of movement of the treated water along the internal channel of the tube with a porous wall, is sent for use in technical waiting.

The use of a porous element with a pore size of 1-5 μm at the first stage of microfiltration is due to the fact that even at the first moments of preliminary filtration, due to the microorganisms present in the treated water, this pore size allows the formation of a dynamic membrane on the surface of the inner channel of the tube with a porous wall (the so-called self-charging filter), which additionally increases the degree of purification and disinfection of the treated water. The process is conducted in a continuous automatic mode.

As the tube material, porous titanium or radiation-modified porous polyethylene are used, the production technology of which is cheaper and simpler than, for example, ceramics.

Periodic alternation of pre-filtration modes: microfiltration and microfiltration + regeneration of the filter element - leads to fluctuations in the flow rate of water that has passed the first stage of microfiltration, so the water flow rate after pre-filtration is averaged to 15-20 l / h. Such a flow rate allows saturating the treated water with silver ions in the stream, performing sorption treatment of the water and the subsequent second stage of microfiltration with the exception of the possibility of secondary bacterial infection of the used sorbents and a porous filter element.

In addition, the flow rate of the treated water of 15-20 l / h allows in the domestic environment to saturate the treated water with silver ions in the stream, without using any additional containers and operations to obtain a solution of a disinfecting agent containing silver ions, which greatly simplifies, speeds up and reduces the cost of the proposed method, while any silver ionizers can be used that allow you to configure the ionization system for a given flow rate.

Saturation of the treated water stream with silver ions is carried out to a silver concentration of 0.1-0.0025 mg / l in order to ensure reliable disinfection of the treated water at all subsequent stages of its treatment, to prevent secondary bacterial infection of the used sorbents and porous filter element in the second stage microfiltration, while ensuring the norms of existing Russian and European standards.

The saturation of the treated water with silver ions in the stream is carried out automatically, for example, using an ionizer with silver electrodes. Depending on the quality of the source water, a certain distance between the electrodes is established with subsequent adjustment of the amount of silver ions in the treated water by varying the current strength on the electrodes.

Processing pre-filtered water with an average flow rate of 15-20 l / h with silver ions allows you to obtain a bactericidal effect and maximize the activation of the treated water, destroying the compounds dissolved in the water and destroying the enzyme systems of microorganisms remaining in the treated water after the first microfiltration stage, before its subsequent sorption processing.

Sorption treatment is carried out depending on the quality of the source treated water in one or more stages, while at the last stage, activated carbon is used as a sorbent.

In particular, sorption processing is carried out in three stages with the sequential use of zeolite, schungite and activated carbon.

The use of a filter element made of ceramic or cermet with a pore size of 0.2-0.4 μm at the second stage of microfiltration, allows you to delay the microparticles of the sorbents carried away with the water stream and remove the excess silver ions with respect to its maximum permissible concentration.

Before the supply of purified water to the consumer, it must be degassed, while the gas bubbles formed during sorption and microfiltration are removed.

Degassing is carried out naturally, for example, in cooler containers or in any household container.

The method is as follows.

The initial tap water is subjected to preliminary filtration, for which, under the influence of pressure in the pipeline, water is supplied to the inner channel of the filter element — a tube made of porous titanium or radiation-modified porous polyethylene, with a pore size of 1-5 μm. The removal of the treated water through the internal channel is blocked, and the process of microfiltration of the treated water through the porous wall occurs. In the first period of processing time, the microfilter is “charged”, i.e. on the surface of the inner channel of the tube with a porous wall, a dynamic membrane builds up due to the presence of microorganisms in the treated water, while contaminants are retained by the porous surface of the microfilter. When the inner channel of the tube is opened, the pressure inside the filter element drops, and the delayed contaminants are washed out by a part of the treated water flow going for technical needs, and the porous surface is regenerated. The flow rate of water passing through the porous wall of the filter element is averaged to a value of 15-20 l / h, followed by processing in the stream of silver ions obtained using an ionizer with silver electrodes, to ensure a silver concentration of 0.1-0.0025 mg / l. Silvered water is subjected to one- or multi-stage sorption treatment, as well as to the second stage of microfiltration through a porous filter element with pore sizes of 0.2-0.4 μm, made of ceramic or cermet, where further purification and disinfection of water occurs. The presence of silver in the stream helps prevent secondary bacterial contamination of the sorbents and the porous filter element of the second stage of microfiltration. The use of activated carbon sorption stage at the only or the last purified water during the movement of the water makes it possible to catch the remaining impurities, residual chlorine and / or excess silver. The use of the second stage of microfiltration makes it possible to retain particles of sorbents carried away by the water flow from the previous stages of sorption, as well as an excess of silver. Formed in the sorption process, as well as in the second stage of microfiltration, gas bubbles are released from the purified water at the stage of degassing. Then the water is ready for drinking.

The sequence of water purification methods proposed in the claimed method, the characteristics of the materials used, as well as the process parameters are optimal for producing drinking water with high organoleptic properties in accordance with existing Russian and European standards.

Examples of the method.

Example 1

The method is implemented on a mobile installation of a modular type.

The source water is tap water with permanganate oxidizability of 6.4 mg / L. The remaining parameters correspond to the parameters of Moscow tap water. The pre-filtering module consists of a cylindrical body, in which a filter element is installed, made in the form of a tube of radiation-modified porous polyethylene with a pore size of 1 μm, the inlet of which is connected to the water supply, one of the exits to the process water tap, and the other through the water supply - with modules installed in the cooler - a device for supplying high-quality cold and / or hot water for drinking needs. During the passage of purified water through the pre-filtration module, a dynamic membrane is formed on the surface of the inner channel of the tube with a porous wall, formed by microparticles contained in the original tap water, which helps to increase the degree of its purification and disinfection already at the first stage of pre-filtration. When the process water tap is opened, a pressure drop occurs in the internal channel of the tube with the porous wall and the flush of impurities trapped therein is carried out, carried away with the flow of water going for technical needs. The effect of regeneration of the porous wall of the tube is enhanced by the pressure difference in the channel of the tube and the cooler’s water pipe, while previously purified water rinses the capillaries of the porous wall of the tube in reverse pulse mode and loosens the dynamic membrane. A module is mounted in the cooler for averaging the flow rate of pre-filtered water to 15 l / h, a silver ionizer that provides a silver concentration of 0.05 mg / l, a sorption purification module containing zeolite, shungite and activated carbon located along the course of the water, and a module for the second microfiltration stage made of ceramics with a pore size of 0.3 microns, as well as two containers of 3 liters. The sequential passage of purified water through all modules allows to achieve a decrease in permanganate oxidation to less than 2 mg / l with a simultaneous content of residual silver not exceeding 0.0025 mg / l, which meets the requirements of not only the Russian, but also the European standard, while all other indicators purified water also comply with established standards. Natural degassing of water before consumption occurs in tanks installed in the cooler.

Example 2. Purification is subjected to water with the initial parameters according to example 1.

All modules are mounted under the sink with an additional faucet installed on the sink for high-quality drinking water, while for natural degassing, for example, a two-liter jug similar to that used in modern household filters is used.

The pre-filtration module consists of a cylindrical body in which a filter element is installed, made of a titanium tube with a porous wall with a pore size of 5 μm, while the input of the module is connected to the water supply, and one of the exits to the process water tap. Another outlet - the outlet of pre-treated water - is connected through a water conduit to the subsequent modules for the post-treatment and disinfection of the treated water and to a high-quality drinking water tap installed on the sink. Periodic opening of the process water tap allows you to regenerate the filter element of the pre-filter module. The module for averaging the flow rate of pre-filtered water is adjusted to provide a flow rate of 20 l / h, the silver ionizer provides a silver concentration of 0.0025 mg / l in the flow, the sorption purification module contains activated carbon, and the module of the second microfiltration stage is made of cermet with a pore size of 0, 3 microns. After passing all the purification modules, the permanganate oxidizability of the purified water is less than 2 mg / l with a simultaneous content of residual silver not exceeding 0.0025 mg / l. All other indicators of purified water comply with the norms of Russian and European standards.

The proposed invention allows to obtain an inexpensive, reliable and environmentally friendly technology for deep purification of domestic drinking water to Russian and European norms and standards due to the joint use in the claimed sequence of flow pre-filtration of treated water, its saturation in the stream with silver ions, as well as mechanical disinfection by microfiltration through pores with a size of 0.2-0.4 microns, followed by degassing.

Claims (6)

1. The method of deep water purification, including its preliminary filtration, two-stage microfiltration through a porous filter element, ion treatment of the disinfecting agent, sorption treatment and the supply of purified water to the consumer, characterized in that the preliminary filtration of the treated water is carried out at the first stage of microfiltration through a filter element made in the form of a tube of porous titanium or radiation-modified porous polyethylene with a pore size of 1-5 μm, in the direction perpendicular water flow, with periodic diversion of part of the treated water in the direction of movement of water for use in technical needs, the water flow after preliminary filtration is averaged to a value of 15-20 l / h with subsequent processing by saturation with a ion of a disinfecting agent, which is used as silver, to ensure a silver concentration of 0.1-0.0025 mg / l, and then the water is subjected to sorption treatment, the second stage of microfiltration through a porous filter element made of ceramic ki or cermets with pore sizes of 0.2-0.4 microns, and degassing. 2. The method according to claim 1, characterized in that the saturation of the treated water in the stream with silver ions is carried out in automatic mode. 3. The method according to claim 1 or 2, characterized in that the sorption treatment is carried out in at least one stage using activated carbon as a sorbent. 4. The method according to claim 3, characterized in that the sorption treatment is carried out in two or more stages, while activated carbon is used as the sorbent in the last stage. 5. The method according to claim 4, characterized in that the sorption purification is carried out in three stages using in the first, second and third stages as zeolite, shungite and activated carbon as sorbents, respectively. 6. The method according to claim 5, characterized in that the degassing is carried out in vivo.