RU2261843C1 - Device for reduction of a crust formation - Google Patents

Abstract

FIELD: water preparation; prevention of a crust formation.

SUBSTANCE: the invention is pertinent to the field of water preparation and may be used for prevention of a crust formation on the heating surfaces of the heat-exchange apparatuses, steam and water-heating boilers, for desalination and evaporation of water, in the production processes providing for cycles of evaporation of water solutions, in agriculture, household activities, spa-sanatorium treatment. The device for reduction of a crust formation includes a body, a means of water delivery, a means of a water treatment by its quasi-softening and a means of the treated water withdrawal. A means of a water treatment is made out of spatially globular structure-material with pores of 0.01 - 3 microns size and the water gates through the indicated means at the rate of not less than 5 l/min. In a preferable version the means of the water treatment is made in the form of a hollow cylinder mounted coaxially to the body of the device. At that the ratio of the outside diameter of the hollow cylinder to its internal diameter makes 1.7-1.9, and to its height - 0.2-0.3. The invention allows to reduce considerably a crust formation at boiling of water, and also to decrease labor input at the device production and to simplify its exploitation.

EFFECT: the invention ensures reduction of a crust formation at the water boiling, a decrease of labor input at the device production and simplification of its exploitation.

4 cl, 1 dwg

Description

The invention relates to water treatment and can be used to prevent the formation of scale on the heating surfaces of heat exchangers, steam and hot water boilers, for desalination and evaporation of water, in technological processes, including the evaporation cycle of aqueous solutions, agriculture, everyday life, spa treatment, etc. .

Known devices based on various principles of action and designed to reduce scale formation by softening the water. So, in accordance with (N.N. Abramov. Water supply. M: Stroyizdat, 1982, p. 300), hard water containing Ca and Mg ions is softened with a reagent method to reduce scale formation. Water is passed through a chemical reagent that binds Ca and Mg ions into compounds that are poorly soluble and are easily removed by precipitation and filtration — calcium carbonate and magnesium hydroxide.

In devices containing a thermal softener (in particular, RF Patent No. 2152905 of 02/01/1996, C 02 F 1/20, C 02 F 5/02), the reduction of scale formation is also achieved by reagent softening using lime and soda at a temperature of more than 100 ° FROM. Additional heating allows you to accelerate the removal of stiffness ions. Membrane devices are known (ibid., P. 301), in which the initial hard water moves in the chamber on one side of the cation exchange membrane, and NaCl brine in the chamber on the other side of the membrane. Sodium ions migrate into the membrane and further into the source water, and calcium ions migrate in the opposite direction, i.e. from hard water to brine. Known devices are also designed to reduce scale formation by softening water.

Hard water is processed in essentially the same way in devices known from EP 0056850 from 01/28/1982, IPC C 02 F 1/42, RU 2163568 from 11/30/1999, IPC C 02 F 1/42, etc.

In 1936, a technique was discovered that, without cleaning hardness salts and without degassing, in many cases can prevent scale formation on the surface. The theoretical substantiation of the phenomenon called magnetohydrodynamic (MHD) resonance (or quasi-softening of water) appeared in the 80s of the last century. According to this model, the physical essence of MHD resonance consists in the structural rearrangement of a fluid initiated by the resonant frequency of the Lorentz force. From water with a modified structure, calcium carbonate crystallizes in the form of aragonite. The crystallographic mismatch of the crystals is Fe ₂ O ₃ / aragonite = 0.121, and siderite / aragonite = 0.191. This indicates that scale will be deposited on the heat exchange surface during supersaturations 3.5–4.5 times higher than usual for such conditions. In addition, aragonite has a slightly higher solubility, lower adhesion to steel and cohesion between crystals. Consequently, aragonite, even after crystallization on the surface, will be carried away by the fluid flow in the form of separate crystals. These views are in good agreement with practical results. In addition, it has been repeatedly shown that water, which underwent structural rearrangement in the MHD resonator, is able to wash off previously deposited scale. This is explained by the fact that the crystallization of calcium carbonate from such water is in the form of aragonite. The crystallographic mismatch between calcite and aragonite is 0.14, i.e. Aragonite growth occurs on the surface of calcite. At the same time, calcite recrystallizes into aragonite. As a result of lower adhesion of aragonite to the surface of the metal and lower cohesion of aragonite crystals to each other, the previously formed scum loosens, exfoliates from the surface and is carried away by a stream of water (V. A. Prisyazhnyuk. Physicochemical principles for preventing crystallization on heat-exchange surfaces. Plumbing, 2003, No. 10, p.30). The prior art devices are known whose operation is based on the above principle, which allows to reduce scale formation.

Thus, magnetic water treatment devices (in particular, RF Patent No. 21118614 dated 03/05/1997, C 02 F 1/18) can reduce scale formation due to quasi-softening of water. In such devices, hard water is passed through a quasi-softened water means - an element (magnetron) containing a permanent magnet or an electromagnet, in which 20-30% of the total liquid is subjected to magnetic processing in a time-variable and spatially gradient magnetic field. The specified magnetic treatment allows you to get water that does not give precipitation when boiling. A well-known device protected the optimal mode of quasi-softening (not the entire volume of water is subjected to magnetic treatment, but only part of it). In other devices of this type, as a rule, with the help of a magnetic field they affect all the transmitted water.

The known device in technical essence is the closest to the claimed device, since both devices provide a reduction in scale formation due to the effect of quasi-softening. The known device disclosed in the patent of the Russian Federation No. 21118614 dated 03/05/1997, C 02 F 1/18, we have chosen as a prototype.

The objective of the invention is to provide a device that can significantly reduce scale formation during boiling water, as well as labor costs in the manufacturing process of the device and simplify its operation. The technical result is achieved by the fact that in the device for reducing scale formation, including a housing, a water supply means, a quasi-softening water treatment means and a treated water removal means, the water treatment means is made of an ion-exchange material of a spatially globular structure (ASG).

It should be noted that ASG is a globular three-dimensional ion exchanger having a globule size of 5-7 microns. Microglobules in PGS ion exchanger form a regular highly permeable structure, which is due to the spontaneous self-regulating mechanism of polymer formation. The average pore size is 1-3 microns, the total porosity is more than 65 vol.%. Typically, this material is used for sorption processes at high transmission rates of solutions. Since the size of microglobules of PGS ion exchanger is two orders of magnitude smaller than that of standard granite ion exchangers (5-7 μm versus 0.5-0.7 mm), the volumetric transmission rates of solutions can reach values that are 100 times or more higher than the transmission rates of solutions through a fixed layer of ion exchanger of ordinary granulation (1000-2000 against 10-15 beats per hour, respectively). The structure and properties of PGS ion exchanger are known, for example, from the Encyclopedia of Polymers. M .: Publishing house Soviet Encyclopedia, 1972, p.652. Various modifications of the method of producing ASG material, for example, in accordance with A. with. USSR 1378319 dated 05.23.1985, C 08 J 5/20, C 08 G 8/22 and A.S. The USSR 1023788 of 10.24.1980, C 08 J 9/10 can significantly expand the range of sizes of its pores and thereby increase its permeability when working as a sorbent.

The experimental studies carried out by the authors of the present invention provided evidence that the interaction of water with ASO material leads to physicochemical changes in its structure, similar to the state of water after magnetic treatment. The proximity of these processes is indicated by the absence of sediment on the surface of the heating devices for a long time of their operation and the formation of easily removable aragonite after prolonged boiling of water. In both processes, the amount of hardness salts in water does not decrease, i.e. quasi-softening of hard water takes place.

It is necessary to point out that the new effect discovered by the authors is currently being comprehensively studied in order to explain the mechanism of interaction of hard water with ASG material, including with the involvement of specialists from various fields of science and technology.

The preferred form of water treatment when implementing the inventive device is a hollow cylinder made of ASG polymer with pores with a size of 0.01-3 microns. The structure of the polymer matrix corresponds to the formula:

Moreover, the housing of the device is also cylindrical. The ratio of cylinder parameters made of ASG material is characterized as follows: the ratio of the outer diameter to the inner diameter is 1.7-1.9, and the height is 0.2-0.3.

The invention is illustrated in the drawing, which shows a General view of the device in section, where 1 is a hollow body made of steel, or plastic, or any other suitable material, 2 is a water treatment tool for its quasi-softening, made in the form of a hollow cylinder made of ASG material installed coaxially to the housing 1 with a gap into which water is supplied by means of a water supply (for example, a pump) is not shown. From the device, water is discharged using a treated water outlet (not shown). Cylinder 2 is locked with a plug 3, 4 - the cover of the device.

The claimed device operates as follows. Water containing hardness salts is directed by means of water supply to the gap formed by the device body 1 and the hollow cylinder 2. From the gap, water passes through the pores of the ASG material into the internal cavity of the cylinder 2. The required water transmission rate is usually chosen by experienced ones to obtain the maximum effect by way. For a device with a cylinder 2 made 245-247 mm high, with an outer diameter of 73-75 mm, and an inner diameter of 40-42 mm, a speed of at least 5 l / min is optimal. Treated water is discharged by means of a drain of treated water to a storage tank or directly for consumption. In the first 30-60 minutes, the usual filtration of water through the ion exchange resin is observed with a certain decrease in the content of hardness salts (by 10-15%); subsequently, during the treatment of water, the content of hardness salts remains unchanged, but such scale does not form upon boiling. Only after a period of the order of 100-200 hours (depends on the concentration of hardness salts) is the formation of loose white easily precipitated from the surface of the heater precipitate (aragonite).

When implementing the inventive device, the inner cylinder 2 was made of an inert porous material — an ASG polymer with pores of 0.01–3 μm in size. The body of the device is placed in a case made of polypropylene. The inventive device is illustrated by the following example. The device manufactured according to the invention was used to treat water containing CaCl ₂ · 6H ₂ O and MgCl ₂ · 6H ₂ O. Water was passed through the device at a speed of 5 l / min. The parameters of the source water and data on the formation of scale during boiling of the treated water are presented in the table.

WEDNESDAY Color grad Turbidity mg / L pH Iron mg / L Calcium Mg-eq / L Scale formation Source water 15.0 0.0 7.0 0.05 7.0 After short boiling, a dense precipitate forms on the heating surface - calcite Water after treatment in the device 14.0 0.0 7.0 0.05 7.0 After prolonged boiling, a loose film is formed on the surface of the water - aragonite

The data presented indicate that when boiling water treated in the inventive device, scale is formed after prolonged boiling. In flow heaters, a loose sediment in the form of a light film rises to the surface with a stream of water and is easily removed as a foam. When boiling stagnant water, a light film rises to the surface of the water.

X-ray diffraction data indicate that the precipitate is aragonite.

Water analyzes were carried out in accordance with the following regulatory documents:

GOST 2874-82 Drinking water. Hygienic requirements and quality control.

GOST 3351-74 Drinking water. Methods for determining taste, smell, color and turbidity.

GOST 4011-72 Drinking water. Methods for measuring the mass concentration of total iron.

GOST 4974-72 Drinking water. Methods for determination of manganese content.

Claims (4)

1. A device for reducing the formation of scale, including a housing, a means of water supply, a means of treating water by quasi-softening and a means of draining treated water, characterized in that the water treatment means is made of a material of a spatially globular structure (ASG). 2. The device according to claim 1, characterized in that the water treatment means is made of ASG material with pores of 0.01-3 μm in size, and water is passed through the said agent at a speed of at least 5 l / min. 3. The device according to claim 2, characterized in that the water treatment means is made in the form of a hollow cylinder mounted coaxially to the device body. 4. The device according to claim 3, characterized in that the ratio of the outer diameter of the hollow cylinder to its inner diameter is 1.7-1.9, and to a height of 0.2-0.3.