RU153835U1 - DEVICE OF EXPRESS ANALYSIS OF QUALITY OF CLEANED WATER - Google Patents

Abstract

A device for express analysis of the quality of water being purified, which includes a housing, a UV radiation source connected by a group of wires to a power source through a choke, and a UV radiation receiver connected to a power source and a central control unit, a quartz tube, input and output pipes for the test water, characterized in that the UV radiation source and the UV photodetector are installed opposite each other on the outside of the quartz tube and are not in contact with the water stream.

Description

The utility model relates to devices for operational analysis and quality control of water treatment.

It is known the use of spectrophotometers in the UV region for the rapid assessment of the quality of wastewater treatment from organic contaminants. The method is developed by the Ministry of Housing and Communal Services of the RSFSR Order of the Red Banner of Labor Academy of Public Utilities named after K.D. Pamfilova, Department of Scientific and Technical Information of the Academy of Public Utilities (ACH) in Moscow in 1981. This device is intended for laboratory workers in wastewater treatment plants that monitor wastewater treatment. The basis of the known control device is the ability of the vast majority of organic substances of various classes to absorb light in the region of 250-270 nm. In this area, unsaturated compounds and aromatic compounds with various atomic groups are intensively absorbed, including proteins, phenols, humic, ligninsulfinic acids and other complex compounds. Inorganic ions, with few exceptions, do not absorb in this region. The essence of this utility model is as follows: with the help of a device, the optical density (UV-indicator) of wastewater is measured at a certain wavelength, and by comparing this value for a while with the values of the normalized indicators characteristic of this particular treatment station, it can be established UV levels corresponding to well and poorly treated wastewater and, thus, to control the content of residual organic contaminants in the discharged effluent by the magnitude of the UV index. To implement the UV method, a spectrophotometer of any model can be used that provides measurement in the UV region of the spectrum, for example, SF-16 or SF-26. In the known device, the UV value (A ₂₅₄ ) is measured at a fixed wavelength of 254 nm in a quartz cell with a layer thickness of 10 mm. As a comparison solution, distilled water is used. Duration of determination is 5-10 minutes.

The disadvantages of the known method and device are that for its use in the field of quality control of water treatment it is necessary:

1. A specially equipped room (laboratory) in which sampling and preparation of water samples for analysis is possible;

2. Special expensive instruments - spectrophotometers, through which the analysis of water quality is performed;

3. Specially trained people, specialists who know how to work on a spectrophotometer and who have sufficient knowledge to evaluate data taken with a spectrophotometer, to analyze the quality of a water sample;

4. For the analysis of water, one specific wavelength is used, it is equal to 254 nm.

5. Measurements using a known device are carried out periodically with a sampling frequency and continuous monitoring of water quality in real time is not provided.

6. To carry out the determination, it is necessary to carry out the selection, preservation, preparation and transportation of water samples to the place of analysis; there is also a limitation on the number of contaminants controlled in water samples that occurs due to the use of one wavelength for analysis (254 nm).

These disadvantages are eliminated in the proposed device for the rapid analysis of the quality of the purified water.

The technical result of the claimed utility model is to increase the reliability and quality of water purification from pollution by providing continuous monitoring of water quality in real time.

This technical result is achieved by the fact that a device for express analysis of the quality of water to be treated is proposed, consisting of a UV radiation source, which is used as a mercury lamp emitting ultraviolet in the range 205-305 nm, a broadband UV photodetector (sensor) based diamond materials, while the quality control sensor for water purification includes: a housing, a UV radiation source connected to a power source through a choke and a UV radiation receiver connected to a power source and prices the control unit, the quartz tube, the inlet and outlet pipes for the test water, the UV radiation source and the sensor are installed opposite each other, the source and sensor are not in contact with the water flow that is directed through the quartz tube, the control is carried out in a dynamic mode, and the quality analysis purified water is carried out in real time on the integrated functional characteristic of absorption in the UV region in the same wavelength range with a linear velocity of water flow of 1-2 m / s

The operation of the device for express analysis of the quality of purified water is based on continuous measurement of the absorption value of the flow of purified water in the ultraviolet region in real time. Stationary laboratory spectrophotometers work on the same principles, but they work in a static mode and allow measuring the absorption of discrete samples inserted into the cell compartment .

The proposed utility model is illustrated in the drawing, where in FIG. 1 shows a General diagram of the device.

A general view of the water quality control unit is shown in Fig. 2. The water quality control unit is a box made of stainless steel in which a quartz tube is fixed. Purified water flows through the tube and is subject to quality control.

The DKB-9 lamp shown in FIG. 3

To ensure the normal inclusion of the lamp, a choke is used (Fig. 4).

To work in the water quality control unit, a "sun-blind" diamond UV - photodetector FA - 3 was selected (Fig. 5.).

The device for express analysis of the quality of purified water structurally includes the following elements:

- building 1),

- a source of UV radiation (2),

- quartz tube (3),

- UV radiation receiver (4),

- inlet and outlet nozzles (5.6)

- wire to the power source (7),

- a wire to the central control unit (CBU) (8).

A distinctive feature of the proposed utility model is that a bactericidal lamp DKB-9 to the irradiator "Sun UFB-04" was used as a source of UV radiation. The DKB-9 lamp is a powerful source of ultraviolet radiation. Generating electromagnetic waves in the range from 205 nm to 305 nm, it is widely used as a quartz source for disease prevention, and is also widely used in other areas of human activity.

The luminous flux of the lamp is 2400 lux, and the service life (duration of effective burning) is 6000 hours.

The DKB-9 lamp is equipped with bactericidal irradiators "Sun OUFB-04", irradiators "Crystal" open and closed types.

Lamp DKB-9, version G23 of Saransk production is the prototype of the Philips TUV LP-S 9W / 2P G23 lamp.

Thus, a distinctive feature of the proposed device for the express analysis of the quality of the purified water is the structural support of the UV radiation source not at one wavelength (254 nm), but in the wavelength range of 205-305 nm and continuous monitoring of water quality in real time . This feature allows water quality control over a much wider range of pollutants that are absorbed in the UV range.

It is known that ordinary photographic materials are used to detect and record ultraviolet radiation. To measure the radiation power, bolometers with sensors sensitive to ultraviolet radiation, thermocouples, photodiodes are used.

A UV-photodetector based on diamond materials, which is the basis for creating electronic solar-blind optical UV-range sensors, was used as a UV-radiation detector supplied by a DKB-9 lamp.

For use in the proposed device, a “sun-blind” UV photovoltaic diamond detector with a potential well (sensitivity threshold of 190-230 nm) FPYA-1 manufactured by UralAlmazInvest LLC was selected.

Thus, the distinguishing feature of the UV detector used in the device for express analysis of the quality of the water being purified is the ability to receive ultraviolet rays in a wide range of the ultraviolet region, which contributes to their full interaction with the source of ultraviolet radiation - a DKB-9 lamp

To indicate the liquid level and measure absorption in the UV region of the spectrum, a quartz tube is used that does not absorb light in the UV spectrum.

Tubes made of transparent quartz glass are used to measure the liquid level, for electric heaters, for various devices and apparatuses, and are designed to operate at temperatures up to 1250 ° C.

The tube has an outer diameter of 20 mm and withstands a maximum pressure of 30 kgf / cm ² . The ends of the tube before installation are cut and ground.

Main technical specifications:

- resistance to temperature increase up to 1200 ° C;

- resistance to aggressive environments (alkalis, acids, except hydrofluoric and phosphoric);

- high optical and wave transparency of quartz;

- color - transparent.

Options:

- ribbing is not standardized;

- cracks, cuts and crystalline inclusions are not allowed;

- the tube is resistant to crystallization when heated to 1200 ° C for 2 hours;

- thermally stable when heated to 1000 ° C, followed by cooling in running water (15 heat exchange);

- chemically resistant to inorganic acids (except hydrofluoric and phosphoric);

- resistant to darkening.

The sensitivity of the photodetector to organic pollution can be varied by changing the magnitude of the applied voltage to the photodetector (water quality control sensor).

To assess the performance of the proposed device, water was contaminated with a state standard sample of petroleum products containing benzene, isooctane and hexadecane in a percentage of 25.0, 37.5 and 37.5%, respectively, at a concentration of 1 mg / ml, followed by passing contaminated water through a treatment plant water equipped with the proposed water quality control devices.

Test results of the device for express analysis of the quality of purified water.

To test the operability of the prototype model of the express-analysis of the quality of the treated water, a block-modular installation with a three-level system for treating wastewater and water sources from oil products was used.

At the same time, water samples were taken to control the residual content of petroleum products on a gas-liquid chromatograph.

Tests of the prototype of the block-modular installation were carried out on the basis of the Institute of Chemical Physics RAS in the period from September 20 to 30, 2012. Prior to the test, calculations were performed on the volume of water that fits into the prototype, taking into account the changes. This was necessary to clarify the volume of introduced stock solutions of petroleum products for one test cycle.

Calculations showed that the volume, m ³ : coagulation block ≈ 0.58; flotation unit ≈ 0.65; sorption block ≈ 0.56; UV irradiation unit ≈ 0.02; pipelines ≈ 0.02. The total volume of simultaneously located water in the installation is ≈ 1.83 m ³ .

Based on the result, the following recommendations were developed: for one test cycle of a prototype sample, 2 m ^{3 of the} initial solution of oil products is enough; sampling (due to their large number) it is advisable to start from the moment the level in the original tank decreases, starting from the “300” mark on the original tank. All samples taken during testing were numbered and recorded in the “Sampling Log”.

Sampling and preservation of samples were carried out directly in the room where the tests were carried out.

The test results of a prototype model of a device for the express analysis of purified water from oil products on model solutions

These tests were carried out in two stages, differing from each other in the concentration of petroleum products in the source water (experiments No. 1-2). The level of calculated concentrations is given in table 1.

The preparation of the initial solution of the required concentration was carried out in the following sequence:

1. 1 m ^{3 of} tap water was poured into the initial container.

2. The following amount of pollutants was added to it:

At the first stage (1 experiment): isooctane - 112.5 mg, hexadecane - 112.5 mg; benzene - 75 mg; clay - 1000 mg, sludge - 1000 mg;

At the second stage (2 experiment): isooctane - 56.25 mg, hexadecane - 56.25 mg; benzene - 37.5 mg; clay - 175 mg, sludge -175 mg;

3. The mixing system was turned on for 10-15 minutes until the color of the solution was equalized throughout the depth of the tank. The following samples were taken of the source water contaminated with a 1 liter hydrocarbon standard: sample 1 — source water for chromatograph calibration; sample 2 - source water from 1 m ³ (experiment 1 without sampling after sensors); sample 3 - source water from 2 m ³ (experiment 1 with sampling after sensors sample 3a - source water from 3 m ³ (experiment 2 without sampling after sensors); sample 13 - source water from 4 m ² with a lower content of the standard for oil products (experiment 2 with sampling after sensors.) Sampling and analysis was also carried out in the first experiment after the first: sample 4, the second - sample 5, and the third - sample 6 sensors while passing a second m ^{3 of} water through the unit, they were taken after passing through the installation 600 l of water, samples 7, 8, 9 - after 700 l of water and samples 10, 11,12 after 800 l of water.

In the second experiment, samples 14, 15, 16 were taken while passing 4 cubes of water through the unit after passing 600 liters of water, samples 17, 18, 19 after passing 700 liters of water and samples 20, 21, 22 after 800 liters of water.

4. The water supply to the unit was turned on at a capacity of 1 m ³ / h.

5. Sampling was carried out three times, when approximately 300, 200, 100 l remained after each control sensor in the tank. The sample volume was 1 liter. Samples were numbered by continuous numbering and recorded in the sampling log. In the first experiment, samples 4, 7, 10 were taken after 1 sensor, samples 5, 8, 11 after the second sensor and samples 6, 9, 12 after the third sensor. In the second experiment, samples 14, 17, 20 were taken after 1 sensor, samples 15, 18, 21 after the second sensor and samples 16, 19, 22 after the third sensor.

6. The analysis of samples was carried out on a gas-liquid chromatograph with a flame ionization detector in the laboratory of the Department of Chemistry and Environmental Engineering, MIIT. The analysis results are presented in the tables.

The average time for one test phase was 55-65 minutes. During the tests, I periodically checked the performance of the installation using a stopwatch and a 2-liter capacity. According to the measurement results, the productivity of the installation was 2 l / 7.4 sec, which corresponds to about 1 cube per hour. Visually, the water quality of suspended solids at the outlet of the installation corresponded to tap water. The obtained generalized results are shown in table 2.

The test results showed that the concentration of benzene contaminants in experiments 1 and 2 after the first sensor exceeded the value 18 mg / l set in the technical specifications. At the same time, the valves of the water treatment system were activated and the contaminated water was redirected to the original tank for re-treatment.

The excess concentration of benzene during the passage of the second cube of contaminated water can be explained by the fact that the bulk of the organic pollutants after passing the first cube remained in the original tank and mixed with pollutants when a new portion of the standard for petroleum products was added to the second cube. Their total concentration was significantly higher than the calculated value of 300 mg / L.

After the second and third sensors, no excess of the content of oil products in the water was detected.

Conclusion: the device for express analysis of the quality of the purified water showed high efficiency for continuous monitoring of the content of oil products in contaminated water and is recommended to continue testing on source water containing real oil products (gasoline, kerosene, diesel fuel, oils, and so on)

The test results of a prototype device for express analysis of the quality of purified water from oil products in the treatment of real wastewater

These tests were carried out in one stage (experiment No. 3). In addition to gasoline and diesel fuel, real wastewater from a car wash in a concentration of 1000 mg / l was introduced into the source water. The level of calculated concentrations for petroleum products is given in table 3.

The preparation of the initial solution of the required concentration was carried out in the following sequence. 1 m ^{3 of} tap water was poured into the initial container. 8. The following amount of pollutants was added to it. At the third stage (experiment 3): AI-92 gasoline 285 ml; summer diesel fuel 285 ml; real wastewater from a car wash in the amount of 1.0 l.

The mixing system was turned on for 10-15 minutes until the color of the solution was evened out over the entire depth of the tank. The water supply to the unit was turned on at a capacity of 1 m ³ / h. Sampling was carried out three times when about 300, 200, 100 l remained after each control sensor in the tank. The sample volume was 1 liter. Samples were numbered and recorded in the sampling log. Samples were analyzed on a gas-liquid chromatograph with a flame ionization detector in the laboratory of the Department of Chemistry and Environmental Engineering, MIIT. The samples analyzed the content of benzene, isooctane and hexadecane.

In accordance with GOST R 52406-2005, the total hydrocarbon content in the sample was determined in the range of C ₈ -C ₄₀ . Considering that benzene was also contained in the samples (formula C ₆ H ₆ ), the total hydrocarbon content in the range of C ₆ -C _{40 was} also determined. The average time for one test phase was 55-65 minutes. During the tests, the installation performance was periodically checked using a stopwatch and a 2-liter capacity. According to the results of measurements, the productivity of the installation was 2 l / 7.4 sec, which corresponds to about 1 cube per hour. To detect benzene and isooctane, a regime with a column temperature of 90 ° C of the detector and injector 120 ° C was set on the chromatograph.

To detect hexadecane and other higher hydrocarbons, a regime was set with a column, detector, and injector temperature of 200 ° C. Visually, the water quality of suspended solids at the outlet of the installation corresponded to tap water.

The average values of concentrations of pollutants in places of water sampling, determined by the results of analysis on a gas-liquid chromatograph, are shown in table 4.

A significant excess of the found total concentration of oil products in the source water in the third experiment compared with the calculated concentration can be explained by the fact that after each experiment (1 and 2 experiments) the initial capacity was not cleaned from oil products and was not washed with clean water and, as a result, oil products from the first two Experiments were accumulated on the walls and in the upper layer of water in the initial container.

The test results showed that the concentration of benzene contaminants after the first sensor slightly exceeded the set value of 18 mg / L. After the second and third sensors, benzene, isooctane, and other petroleum products were not detected in the samples.

The device for express analysis of the quality of treated water worked in normal mode, with the exception of the following cases:

1. In the third experiment, sensor No. 1 was triggered due to an excess of benzene concentration. The installation went into normal mode after 5 seconds.

2. Once the operation of sensor No. 3 was detected, it was most likely that it was a false signal. After 5-10 seconds, the operation of sensor No. 3 returned to normal mode.

Conclusion: a device for express analysis of the quality of treated water has shown high efficiency in monitoring the treatment of real wastewater from oil products (gasoline, summer diesel fuel).

As follows from the results of the tests, when the threshold values of contaminants in the treated water, exhibited during the setup of the sensors are exceeded, the sensor is triggered with a signal to the central control unit. In this case, a signal is issued to the locking equipment, by means of which water is returned to the previous unit for repeated cleaning.

Claims (1)

A device for express analysis of the quality of water to be treated, including a housing, a UV radiation source connected by a group of wires to a power source through a choke, and a UV radiation receiver connected to a power source and a central control unit, a quartz tube, input and output pipes for the test water, characterized in that the UV radiation source and the UV photodetector are installed opposite each other on the outside of the quartz tube and are not in contact with the water stream.

Images