RU2070425C1 - Method for elimination of harmful compounds from capacities with air medium - Google Patents

Abstract

FIELD: elimination of harmful compounds from capacities. SUBSTANCE: gaseous mixture which contains ozone is fed into capacity being treated. Ratio of ozone mass to the mass of eliminated compounds is not less than 4000: 1. Concentration of ozone in treated capacity is not less 0.3 mg/m³. EFFECT: improves efficiency of the method. 2 cl, 3 tbl

Description

 The invention relates to methods for eliminating harmful substances in volumes and premises mainly for agricultural purposes, as well as domestic and industrial premises.

 A known method of eliminating harmful substances, comprising supplying a gas mixture containing ozone to the treated volume. This technical solution is the closest to the claimed. Ozone in this case allows you to effectively oxidize harmful substances or compounds, apply an acidic film to their surface, which greatly reduces the evaporation process of these substances. In addition, oxides of harmful substances and / or compounds are less toxic than these substances themselves.

 The disadvantage of this method is its lack of effectiveness, and often this method does not allow the elimination of harmful substances located in the pores of the surface of premises, furniture, soil, etc.

 The aim of this invention is to increase efficiency and expand its operational capabilities.

 This goal is achieved in that the supply of ozone is carried out at a certain ratio of its mass in the gas mixture and the mass of the seized substance, for example, for mercury vapor not less than 4000: 1, this ratio depends on the type of substance (gaseous or vaporous organic and inorganic substances, vapors and aerosols heavy metals), as well as the fact that the concentration of ozone in the treated volume is set to at least 0.3 mg / cubic meter, and the gas mixture is supplied to the treated volume, maintaining the pressure in the latter equal to the pressure in external gas environment.

 A search conducted in the scientific, technical and patent literature showed that the claimed combination is unknown, i.e. it meets the criterion of "novelty."

 Since this method is implemented using known devices, the claimed meets the criterion of "industrial and applicability".

 And since the effect obtained as a result of using this method is higher and in some cases this method allows you to process the premises with high efficiency, which is unattainable in other ways, the claimed meets the criterion of "inventive step".

 It should be noted that when an ozone-air or ozone-oxygen mixture is injected into a room or in some other volume, excessive pressure arises in this volume, which leads to ozone leakage from this volume. As a result of this, there is a danger of people or animals affected by ozone outside the treated ozone and at the same time the ozone consumption for processing increases.

 When using recirculation, a pressure differential is not created between the treated volume and the external environment, so ozone leakage can only occur due to diffusion or convective flows. Therefore, as practice has shown, it’s quite enough to close the windows and doors for processing residential premises, turn off the supply and exhaust ventilation for the production facilities and also close the windows and doors, to process the area of the production area, install a light frame on the treated area and cover it with a film made of resistant to exposure to ozone material and fix the edges of the film so as to create an isolated volume. In this case, ozone leakage is very insignificant and hazardous concentrations (above the maximum permissible value) are not created even at very high concentration gradients.

Technically, the method is carried out on the example of the removal of mercury vapor, which is quite common in the premises of hatcheries, greenhouses, veterinary stations, etc. as follows. Determine the concentration of mercury vapor in the room and its volume, as well as the maximum permissible concentration of vapor in the treated room, calculate the mass of the seized substance:
g V (C _beg C _add ),
where g is the mass of the seized substance, m;
V volume of the room, cubic meters

From the _{beginning, the} concentration of vapors in the room, mg / m3;
C _additional required vapor concentration, mg / m3.

It should be said that C _add is determined on the basis of maximum permissible norms for the content of harmful substances and / or compounds in indoor air.

According to the obtained value, the required amount of ozone is calculated, which must be introduced into the room:
G 4000 xg,
where G is the required amount of ozone, mg;
Taking the processing time equal to t hours, determine the hourly productivity of the installation P:
PG / t.

In addition, it is necessary that the ozone concentration at the end of treatment be at least 0.3 g / m3. This can be approximately determined based on the following relationship:
C _p K x (W x C _o ) / V,
where W is the productivity of the ozonizing installation by air, cubic m / h;
C _{p the} minimum required concentration of ozone in the room, mg / m3;
With _{about the} concentration of ozone in the gas mixture at the outlet of the ozonizer or ozonation unit;
To the coefficient of self-decomposition of ozone in the volume and on the treated surfaces (depends on the temperature and humidity in the room and the degree of contamination of the treated surfaces).

 Based on experience, a treatment time of 2 to 12 hours should be recommended. With a long time from the moment of infection to the detection of the content of mercury vapor in the room, it is possible to sorb them on the surface (paint, soft upholstery, wood, etc.), some time after processing, the concentration may again increase above the standard value. In this case, the treatment should be repeated, perhaps even several times.

 After that, the installation suitable for the specified parameters is selected and placed either directly in the room or next to it. The room is sealed if the ozone-air mixture is supplied by pumping the ozone-air mixture, or it is simply insulated by closing windows, doors and other openings, and turn on the unit for a certain time. After treatment, it is recommended to ventilate the room and measure the concentration of mercury vapor in it.

 The method can be carried out as follows: the ozonation installation is mounted in a room adjacent to the volume to be treated, and the ozone-air mixture is supplied through this pipeline to the volume, and the gas mixture from the volume to be processed is fed to the inlet of the installation, then they are operated as described above.

 It should be noted that the most suitable for these purposes are ozonation installations that can operate in conditions of high humidity, the presence of dust and aerosols.

Ozone activity with respect to mercury vapor increases with increased temperature, but the degree of ozone decomposition also increases, which reduces the concentration of ozone in the treated volume. In this regard, the calculated concentration values are given for the air temperature in the treated volume from 20 to 27 ^o C. Both when the temperature decreases for every 5 ^o C below the specified value, and when it is exceeded by the same 5 ^o C, the ozone dose should be increased by 2 times.

Example. The rooms were demercurized at an air temperature of 19 ^o C and a relative humidity of 85%. The treatment was carried out with two portable ozonizing units OP-2 with an ozone productivity of 0.7 g / h and an output ozone concentration of 15 mg / cubic meter. Measurement of the concentration of mercury vapor was carried out with the AGP-1 instrument in the evening, at 17-00, before treatment, the rest of the analyzes the next day before work began at 7-00 and at lunchtime. The maximum permissible concentration of mercury vapor in the premises is 0.1 mg / m3. The measurement error of mercury vapor + 10% ozone is 0.1 mg / m3.

 The results of demercurization of premises are shown in table 1.

 Table 2 shows the results of the demercurization of the premises using an OV-1 type ozonizer with a capacity of 0.9 g / h and a concentration of the ozone-air mixture of 0.5 mg / m3.

 From table 2 it follows that, despite the introduction of doses of ozone substantially higher than necessary, the purification did not occur due to the insufficient concentration of ozone in the room.

Table 3 shows the results of processing the premises in which work is carried out using mercury amalgam. The room temperature was 21 ^o C, relative humidity 70%. The concentration of mercury vapor was measured using the OP-1 and OP-2 instrument (manufacturer, Mars plant, Ekaterinburg).

 When processing open areas (streets, platforms, land plots, etc.), it is recommended to process in separate parts an area acceptable for processing, covering it, for example, with polyvinyl chloride or another ozone-resistant film. It is advisable to moisten dry areas before processing so that the air humidity in the treated volume is below 60% (relative humidity).

Claims (2)

1. A method of eliminating harmful substances from a volume with an air medium, comprising supplying ozone in the form of a gas mixture to the treated volume, characterized in that the ozone is supplied at a ratio of its mass in the gas mixture and the mass of the harmful substance not less than 4000 1, and the ozone concentration in the treated volume set at least 0.3 mg / m ³ .  2. The method according to claim 1, characterized in that when the ozone is supplied in the form of a gas mixture into the treated volume, the pressure in the latter is maintained equal to the pressure of the outside air.