RU178726U1 - Device for safe experimental selection of disinfectants for soil disinfection of anthrax cattle burial grounds - Google Patents

Abstract

The utility model relates to technical devices for medical and veterinary disinfection, designed for safe experimental selection of the most effective disinfectants from a large number of known or new disinfectants for disinfecting soil in anthrax cattle burial grounds and in areas of soil contaminated with anthrax pathogens or other dangerous microorganisms that have arisen as a result of burial, slaughter, mortality of sick animals. The device consists of a closed sealed column made of metal and glass or plexiglass, 1000 × 1000 × 2500 mm in size with a sealed hatch equipped with an exhaust valve and a foam deflector, on one of the faces (walls) of the column at different depths (500; 1000 and 1500 mm ) have mounting holes with samplers installed, a staircase with a platform is mounted on the opposite side of the column, a two-section door with hinges and a handle is installed on the metal side of the column, a valve is installed in the bottom of the column to bleed liquid from the columns.

Description

The utility model relates to technical devices for disinfectology, in particular to models of soil foci of anthrax designed for safe experimental selection of the most effective disinfectants from known and new disinfectants for disinfecting soil in anthrax cattle burial grounds or areas of soil contaminated with anthrax pathogens or other dangerous microbes resulting from the burial, slaughter, mortality of sick animals.

The epidemiological situation of anthrax remains difficult due to the existence of natural reservoirs of anthrax microbe, which are cattle burial grounds and stationary disadvantaged territories. A cattle cemetery is a place for long-term burial of corpses of farm and domestic animals that fell from an epizootic or were slaughtered in order to prevent its spread. The maintenance of anthrax cattle cemeteries in safe integrity and preservation is an important state task.

On the territory of Russia, there are about 35 thousand points permanently dysfunctional for anthrax with soil foci, in which 7940 anthrax cattle burial grounds are taken into account. The real scale of the biological hazard posed by the old registered and ownerless soil anthrax cattle burial grounds and territories unsuccessful for anthrax for human life, the country's health and veterinary authorities faced in 2016 during the outbreak of anthrax in the Yamal-Nenets okrug, as a result which were infected by spores of anthrax pathogens from the soil, a large number of people and animals.

To prevent anthrax epidemics in the territory of our country and the CIS countries, urgent and planned targeted work is necessary to eliminate and reorganize old orphan soil anthrax cattle burial grounds and territories unsuccessful for anthrax, using environmentally friendly means and advanced technologies for decontamination of soil and soil.

The most accessible and effective means of decontamination of the soil from anthrax spores may be separate funds from chemical disinfectants with a wide spectrum of antimicrobial activity.

In this regard, an important and urgent task of medicine and veterinary medicine is the experimental selection of highly effective disinfectants for soil sanitation of anthrax cattle burial grounds and the development of technology for soil decontamination from bacterial spores of anthrax pathogens.

For the correct selection of disinfectants for sanitation of large amounts of soil of anthrax cattle cemeteries (from 500 m ³ to 1,000,000 m ^{3 of} soil), it is necessary in pilot industrial devices simulating the physicochemical and biological conditions of the soil cattle cemetery to conduct tests to determine the disinfecting activity of various disinfectants on different soil and soil samples, to develop modes, technologies and recommendations for soil disinfection of anthrax cattle cemeteries in relation to seasonal and climatic conditions eskim conditions in the region, the physicochemical characteristics of the soil, and others.

An analogue and prototype of the proposed device for safe experimental selection of disinfectants for disinfection of soil contaminated with anthrax spores is a device for experimental selection of disinfectants for disinfection of soil contaminated with anthrax spores, described in patent RU 157923, 2015. This device for experimental selection of disinfectants for disinfecting the soil of anthrax cattle cemeteries consists of a closed airtight column 500 × 500 × 2500 mm in size, equipped with airtight hatch with an exhaust air valve for filling the soil and pouring the disinfectant, a door for placing permeable microcontainers with anthrax pathogen spore samples, a receiving sampler for collecting spent disinfectant, a mounting unit for receiving the sampler to the bottom of the column, column support for installation in an room or on an open site.

The main disadvantages of the described device are:

- lack of a sufficient level of biological safety when performing work on testing peroxide disinfectant compositions due to abundant foaming during the interaction of peroxide composite disinfectants with the soil in the device, which leads to its release into the environment through the exhaust air valve of the hatch or open hatch of the column;

- the uniform wetting of all soil layers with a disinfectant and its uniform decontamination are not ensured due to the small cross-sectional area of the device column, in which the solutions of the tested disinfectants easily flow down the walls of the column and quickly reach the bottom;

- it is difficult, inconvenient, and unsafe to search and remove microcontainers with anthrax spores from a highly moistened soil (mud) for transfer to a microbiological laboratory to determine the level of spore inactivation after exposure to soil in the device column;

- does not allow at the intermediate stages of testing to get microcontainers with anthrax spores from the device’s column for transmission to the microbiological laboratory to determine the level of spore inactivation;

- the disinfectant solution does not evenly pass through all soil layers due to the lack of drainage properties of the column;

- sufficient physical security is not ensured when lifting and loading the device column with soil and pouring it with a disinfectant solution due to the lack of a stationary staircase with a platform in the structure of the device;

- does not allow for safe testing of soil unloading from the column into kraft bags after testing, which are to be sent for incineration. Due to the presence in the column of only one door to the entire height of the column of the device, when it is opened, the soil is scattered in large quantities, and the moistened soil drains and falls to the floor.

The technical result of the proposed utility model is the provision of biological and technical safety when performing work on the experimental selection of disinfectants for disinfection of soil contaminated with anthrax spores, facilitating and simplifying the work of placing the device columns at different depths of test tampons soaked in anthrax spores, ensuring the safety of all test tampons during the test and during their removal from the column, providing the possibility of removing test tampons from the column with biomaterial at the intermediate stages of testing to check the level of spore inactivation, modeling of biological, physico-chemical and soil characteristics in anthrax cattle cemeteries, including drainage properties, ensuring the reliability of the results of spore inactivation with a disinfectant at different soil depths and at different stages of disinfection in the installation.

The technical result is achieved by the fact that a device is proposed for safe experimental selection of disinfectants for disinfecting soil contaminated with anthrax spores with a cross-sectional area of the device column 1000 × 1000 mm ² having a foam collector mounted in an airtight hatch on one of the faces (walls) of the column at different depths (500; 1000 and 1500 mm) also having mounting holes with three removable samplers installed in them, the opposite side of the column is equipped with a ladder with a platform, metal g An two-section column has a door with hinges and a handle, the bottom of the column has a valve to bleed fluid from the column.

In FIG. 1 shows a device for safe experimental selection of disinfectants for disinfecting soil contaminated with anthrax spores.

The device comprises a column made of metal and glass or plexiglass, dimensions 1000 × 1000 × 2500 mm and supports (17) 600 mm high with a wide base (18) for firmly securing to the foundation. On the roof (1) of the column of the device is a sealed metal hatch (7) 700 × 700 mm in size with a handle (10) and hinges (9). Its presence allows you to put in the working volume the required amount of soil embankment. An air outlet valve (8) is located on the hatch to relieve excess pressure from the column, as well as a filler neck with a cover (20) for convenient and safe pouring of the disinfectant solution into the working volume. In addition, in the upper part there is a foam drain (21), with the help of which foam formation is removed during the experiment. On the side of the column is a staircase with a platform (22), which allows you to safely raise the experimental means to the required height (Fig. 2).

The column frame of the model is made of metal, corner and channel profiles. The rear wall of the column (2) is made of metal, and a two-section door (4) with hinges (6) and a handle (5) is installed on it. Separate doorways allow the gradual unloading of soil from the column, eliminating the possibility of scattering experimental material, and also facilitate the processing of the inner space of the column after the experiment. A viewing window (3) is located on the adjacent side face of the column, and mounting holes with removable samplers (23) are installed at a height of 500, 1000, 1500 mm (Fig. 3).

The base of the column (11) has a slope N for the best flow of the experimental liquid into the receiving cylinder for collecting the spent solution of the disinfectant (15), in the central part of the bottom of the column there is a drain hole (12) with a filter protective net (13), and a connecting fitting is provided with thread (14). A receiving cylinder is attached to the connecting fitting to collect the spent disinfectant solution for chemical studies of the residual activity of the disinfectant after the experiment. Also around the perimeter of the base of the column are mounted valves for bleeding (19) of excess fluid outside the facility.

The materials used in the manufacture of the parts of the facility are selected taking into account possible critical stresses, the effects of disinfectants, difficult weather conditions, and the tightness conditions are taken into account.

When conducting tests on the proposed device for the safe experimental selection of disinfectants for disinfecting soil contaminated with anthrax spores, a staircase with an anti-slip platform equipped with high rails is provided in its design to ensure the necessary level of operational safety (Fig. 2). At the bottom of the stairs, mounting holes are provided for fastening to the foundation, and to ensure the solidity of the structure, the upper part is attached to the column of the object using a continuous weld. The ladder is fixed in a stationary state, which allows you to load the soil into the column of the device, and then fill it with a solution of disinfectant quickly, efficiently and safely, without using additional protective equipment for high-altitude work.

The microbiological sampler (Fig. 3) is part of the proposed utility model of a device for the experimental selection of disinfectants for disinfecting soil contaminated with anthrax spores, and is a small assembly unit consisting of a holder and a lid connected by a thread. The holder is a molded part made of a durable material resistant to plastic deformation. The outer part of the larger diameter is a handle on which a layer of friction paint is applied or slotted for ease of grip. At the end of the holder, a face drill was made to a fixed depth of 70 mm, and then holes of small diameter were drilled on the outer surface with equal pitch. A gauze test swab is placed inside the central hole, impregnated with a suspension of spores of bacteria of the causative agent of anthrax or bacteria of causative agents of especially dangerous infections at a concentration of 2 × 10 ^9-12 m.k. / 1 ml. The action of the test solution of the test disinfectant on the test swab with spores or bacteria occurs through the penetration of the disinfectant solution through openings of small diameter. To prevent large amounts of soil from entering the test swab, a round lid with a thread is provided at the end of the holder, which is screwed onto the external thread of the holder. The assembled sampler is placed in the corresponding holes of the column and is securely fixed in it. Based on the conditions of tightness and ease of use, a large diameter thread with a small pitch is provided near the handle. To study the effectiveness of the disinfectant at different depths, several such threaded holes are provided, which makes it possible to effectively use the working height of the soil, as well as to increase the accuracy of the obtained experimental data.

Example 1. To test the capabilities of the proposed device for safe experimental selection of disinfectants for disinfecting soil contaminated with anthrax spores, in the experimental selection of the most effective disinfectants for disinfecting soil in anthrax cattle burial grounds, a solution of peroxide composite disinfectant in a concentration of 15% (peroxide hydrogen). To do this, close the door of the column and three microbiological samplers are introduced into the column through openings in the right side wall to a height of 500 from the bottom of the column; 1000 and 1500 mm, are firmly fixed with a thread to the column wall and hermetically closed with a sampler lid to prevent leakage of the disinfectant solution. At the end of each microbiological sampler, one gauze swab soaked in a suspension of bacterial anthrax pathogen spores is placed in its microchamber. Then, the soil is lifted up the device stairs and 2000 kg of dry clay soil is poured through the hatch to the column mark of 2000 mm. A sealed threaded receiving cylinder (chemical sampler) is attached to the bottom of the column to collect the spent disinfectant solution. A microcontainer with a test swab impregnated with a suspension of bacterial spores is also placed in a receiving cylinder to collect the spent disinfectant solution.

After loading the columns of the device, they begin work on disinfecting the soil with a disinfectant. A 15% disinfectant solution in the ratio 1: 3 (disinfectant solution volume / soil volume) is poured through the neck of the column hatch into the ground and left for 24 hours at an average ambient temperature of (8 ± 3) ° C. In the event of excessive pressure of the resulting gas or vapor in the column, the exhaust valve on the column hatch serves as a regulator of the internal pressure in the device. With abundant foaming, the foam is opened and foaming with a hose is collected in a separate container. To improve the drainage properties of the columns of the device, valves are opened to drain excess fluid from the object - into a container for collecting spent disinfectant.

After 24 hours, for a two-time experimental disinfection of the soil, a 15% disinfectant solution is re-poured into the column in a ratio of 1: 4 (disinfectant solution volume / soil volume) and left for another 24 hours at ambient temperature (8 ± 3) ° C. To improve the drainage properties of the columns of the device, valves are opened to bleed excess liquid into a container for collecting spent disinfectant.

After the expiration of the exposure time to the soil with a disinfectant, all microbiological samplers are removed from the column and transferred to a microbiological laboratory to assess the number of viable spores in each experimental sample. Each test swab is removed from the microbiological sampler and suspended in a solution of a universal neutralizer to remove disinfectant residues, then after centrifugation, the precipitate is suspended in a meat-peptone broth or physiological saline. The spore suspension is plated in Petri dishes on Hottinger medium and thermostated for 7 days at a temperature of 37 ° C. A sampler for chemical research is separated from the column of the device and transferred to a microbiological laboratory to determine the presence of live spores in the spent disinfectant, and then it is transferred to a chemical laboratory to determine the residual activity of hydrogen peroxide in the spent solution of the disinfectant.

After completion of work, the door of the device is opened and the column is gradually released and cleaned of soil and disinfectant. The soil from the column is poured into kraft bags and, according to the act, sent to the furnace for burning.

Microbiological studies have shown that after test disinfection of the soil in a safe model of the anthrax cattle burial ground with a 15% peroxide disinfectant solution, there are no viable anthrax spores in all test tampons taken from different soil depths (500; 1,000 and 1,500 mm from bottom of the column), as well as in the spent disinfectant solution. Chemical and analytical studies of the spent disinfectant solution showed that the activity of the agent decreased by no more than 60% of the initial activity.

Thus, the obtained data of microbiological and chemical-analytical studies indicate that a 15% solution of peroxide composite disinfectant in contact with a large amount of soil inactivates spores and loses its initial disinfecting and oxidizing activity by no more than 60%. The proposed device for the safe experimental selection of disinfectants for disinfecting the soil of anthrax cattle burial grounds at all stages of preparation and testing to evaluate the disinfecting activity of peroxide composite disinfectant on soil contaminated with anthrax bacteria spores, ensured a high level of biological and physical safety.

The results allow us to recommend the tested peroxide composite disinfectant for the rehabilitation of soil anthrax cattle burial grounds by double treatment with a 15% solution of the product with an interval between treatments of 24 hours with a total treatment time of at least 48 hours.

Example 2. To test the capabilities of the proposed device for safe experimental selection of disinfectants for disinfecting soil contaminated with anthrax spores, we used a solution of a chlorine-containing composite disinfectant at a concentration of 6% active chlorine. To do this, close the column door and enter into it three microbiological samplers with test swabs soaked in anthrax pathogen spores to the column height from its bottom 500; 1000 and 1500 mm, are firmly fixed with a thread to the column wall and hermetically closed with a sampler cap to prevent leakage of the disinfectant solution. Then, the soil is lifted up the device stairs and about 2000 kg of dry chernozem is poured through the hatch. A sealed threaded receiving cylinder (chemical sampler) is attached to the bottom of the column to collect the spent disinfectant solution.

For experimental disinfection, a 6% disinfectant solution is poured into the soil through the neck of the column hatch in a ratio of 1: 3 (disinfectant solution volume / soil volume) and left for 48 hours at an average daily ambient temperature of (16 ± 3) ° C. In the event of excessive pressure of the resulting gas or vapor in the column, the exhaust valve on the column hatch serves as a regulator of the internal pressure in the device. To improve the drainage properties of the columns of the device, valves are opened to bleed excess liquid into a container for collecting spent disinfectant.

After 48 hours, for repeated experimental soil disinfection, a 6% disinfectant solution is poured into the column in a ratio of 1: 4 (disinfectant solution volume / soil volume) and left for another 24 hours at ambient temperature (16 ± 3) ° C. To improve the drainage properties of the columns of the device, valves are opened to vent excess fluid from the object.

After the expiration of the double exposure time of the disinfectant to the soil (72 hours), all microbiological samplers are removed from the column and transferred to a microbiological laboratory to assess the quality of soil disinfection. The sampler with the spent disinfectant is separated from the column of the device and transferred to the microbiological laboratory to determine the presence of live spores in the spent disinfectant, and then sent to a chemical laboratory to determine the residual activity of active chlorine in the spent solution of the disinfectant.

Then the two-section door is opened and the column is gradually released and cleaned of soil and disinfectant.

Microbiological studies have shown that in the proposed safe device for the experimental selection of disinfectants for disinfection of soil contaminated with anthrax spores, on experimental test tampons contaminated with anthrax spores, including test tampons in the spent solution of the drug, after twice disinfecting the soil with 6% solution chlorine composite disinfectant for 72 hours there are no viable anthrax spores. Chemical and analytical studies of the spent disinfectant solution showed that the activity of the agent decreased by no more than 47% of the initial activity. The results allow us to recommend the proposed safe device for the experimental selection of disinfectants for disinfecting soil contaminated with anthrax spores, and the tested chlorine composite disinfectant for sanitation of soil anthrax cattle burial grounds at a concentration of 6% active chlorine at a treatment time of 72 hours.

Thus, the obtained test results confirm that the proposed safe device for the experimental selection of disinfectants for disinfection of soil contaminated with anthrax spores provides the required biological and physical safety conditions at all stages of testing, including all preparatory and final work on the installation, allows you to simulate the structure, climatic conditions, biological, chemical and physical properties and soil characteristics, including its drainage properties, in ibireulynnyh cattle cemeteries, ensures the reliability of the results of inactivation of spores with a disinfectant at different depths of the soil and at different stages of disinfecting it in the installation, which allows you to use the proposed safe device at the stages of experimental selection and testing of the most effective disinfectants for disinfecting the soil of cattle cemeteries, at the stages of developing regimes for disinfecting the soil depth, as well as in the process of developing technology for soil disinfection of anthrax cattle elnikov and soil at the places of slaughter and mortality of sick animals.

Specification for a draft design of a utility model for the safe experimental selection of disinfectants for soil disinfection of anthrax cattle burial grounds.

1. The roof of the column

2. The column wall

3. Viewing window

4. Two-section door

5. door handle

6. Door hinge (4 pcs.)

7. Hatch for loading

8. Exhaust air valve

9. Hatch hinge (2 pcs.)

10. Hatch handle

11. The base of the column

12. Drain hole

13. Safety net

14. Connecting nipple

15. The receiving cylinder

16. Micro-container with test microbes

17. Column support (4 pcs.)

18. The base of the support

19. Valve for bleeding (4 pcs.)

20. Filler neck with lid

21. Foam tap

22. Staircase with landing

23. Sampler with cap

Claims (2)

1. A device for the experimental selection of disinfectants for disinfecting the soil of anthrax cattle cemeteries, consisting of a closed airtight column made of metal and glass or plexiglass, equipped with an airtight hatch with an exhaust air valve for bleeding excess pressure and a neck for disinfectant filling, a door for unloading soil from the column , a receiving cylinder for collecting the spent disinfectant solution attached to the bottom of the column, column supports for installation in a room or on rytoy site, characterized in that the column cross-sectional area is 1000 × 1000 mm ^2, an airtight hatch penootvoda device provided on one of the faces (walls) of the column at 500; 1000 and 1500 mm mounting holes are located with samplers installed, a ladder with a platform is fixed on the opposite side of the column, a two-section door with hinges and a handle is installed on the metal side of the column, a valve is installed in the bottom of the column to drain the liquid from the column. 2. The device according to claim 1, characterized in that the staircase with an anti-slip platform is equipped with high rails, mounting holes are provided in the lower part of the staircase for fastening to the foundation, and the upper part of the staircase is attached to the column with a continuous weld.

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