RU2805103C1 - Gas release and afterburning unit - Google Patents

Abstract

FIELD: chemical industry; environmental safety.

SUBSTANCE: invention relates to devices for destruction of harmful gases and can be used to ensure safe operation of chemical reactors. The device comprises a housing with a conical base and a branch pipe equipped with an electromechanical valve; the branch pipe is made with capability of leak-tight installation in a hole made in the chemical reactor cover. A gas burner fuelled from a tank containing natural gas is fixed inside the body, equipped with an electromechanical gas flow regulator and an automatic piezoelectric ignition unit, as well as a gas detector for detecting harmful components in gases released from the reactor. Power outputs of the control unit of the gas exhaust and afterburning unit are connected to the electromechanical valve, the electromechanical regulator and the automatic piezoelectric ignition unit, and the output of the gas detector is connected to the measuring input of the said unit.

EFFECT: enables combustion of carbon monoxide in order to prevent its release into the atmosphere.

8 cl, 3 dwg

Description

The invention relates to devices for the destruction of specific waste, namely harmful gases, and can be used to ensure the safe operation of chemical reactors. The proposed technical solution makes it possible to prevent the release of toxic gases, in particular carbon monoxide, from the reactor core by afterburning the said gases when releasing them from the reactor to produce non-hazardous compounds in the gas phase [1, 2, 3].

Many well-known technical solutions are aimed at increasing the efficiency of afterburning gases by mixing them well in the working space of the furnace. In some sources [4], this problem is proposed to be solved by placing oxygen and combined burners around the circumference of the furnace, as well as choosing the optimal angle of inclination of the mentioned burners to the horizontal and vertical surface.

For example, a smoke destructor (gas afterburning furnace) is known from the prior art. The device (US3817712B1, IPC F23C9/04, F23G7/06, publ. 06/18/1974) consists of a cylindrical afterburning chamber of the cyclone type, a pipe for introducing flue gases and a burner for supplying fuel combustion products, installed tangentially to the furnace body, a pipe for exiting products combustion and ash removal pipe [5].

The main disadvantage of the known furnace for afterburning gases is the use in its design of two tangential pipes, the first of which is intended to introduce flue gases into the furnace, and the second is for introducing fuel combustion products from the burner into the furnace. As is known, one of the conditions for intense combustion of gaseous substances is good mixing of combustible components with air. At the same time, the design of the furnace for afterburning flue gases does not allow for high mixing, which occurs due to the fact that the flue gases, entering the cylindrical body tangentially, meet the fuel combustion products coming from the nozzle, which are also introduced into the cylindrical body tangentially and in the same direction. These two gas flows move in a spiral and are twisted in the same direction, which leads to equalization of the speed of the gases and a deterioration in their mixing.

The closest device in design to the proposed unit for the release and afterburning of gases and chosen as a prototype was recognized as a cyclone-type furnace for afterburning flue gases (RU2230989C2, IPC F23G7/06, publ. 06/20/2004). The furnace is made in the form of a cylindrical body, equipped with a conical bottom with a device for collecting ash, a lid with a pipe for removing combustion products, and a device installed tangentially to the cylindrical body for introducing flue gases into the furnace. In this case, the device for introducing flue gases is made in the form of an ejector-type mixer, along the axis of which a plasmatron is installed, which ejects flue gases with a plasma jet of oxidizing air [6].

The disadvantage of the known furnace is that an ejecting stream of high-temperature (5000-6000°C) plasma air jet is used as a medium for afterburning flue gases, which requires the use of heat-resistant steels for the manufacture of the furnace body. In addition, given that the design of the furnace does not include carbon monoxide sensors that make it possible to determine its volume fraction in the flue gases and control the power of the plasmatron, the known furnace has a very low efficiency.

The technical problem to be solved by the design of the proposed unit is to increase the efficiency of afterburning of gases released from chemical reactors.

This problem is solved in that the gas exhaust and afterburning unit contains a housing with a conical base and a pipe equipped with an electromechanical valve, wherein the pipe is designed to be sealed in a hole made in the lid of a chemical reactor. A gas burner is fixed inside the housing, powered by a container with natural gas, equipped with an electromechanical gas flow regulator and an automatic piezoelectric ignition unit, as well as a gas detector for detecting harmful components in the gases released from the reactor. The power outputs of the control unit for the gas exhaust and afterburning unit, equipped with a radio module, are connected to the electromechanical valve, the electromechanical regulator and the automatic piezoelectric ignition unit, and the output of the gas detector is connected to the measuring input of the mentioned unit.

A positive technical result provided by the set of features of the device disclosed above is the possibility of fixing it in the opening of the lid of a chemical reactor and using a unit for afterburning dangerous gases, such as carbon monoxide, in order to prevent them from entering the atmosphere, which significantly increases the safety of using chemical reactors, in particular in the production of nickel carbonyl.

The design of the technical solution is illustrated by drawings, where in Fig. Figure 1 shows the appearance of the gas release and afterburning unit in an isometric projection; in fig. Figure 2 shows a technical sketch of the gas release and afterburning unit in section; in fig. Figure 3 shows a block diagram of the gas release and afterburning unit.

The gas release and afterburning unit is arranged as follows.

Its basis is a hollow cylindrical perforated body 1 (perforated holes are not shown in the figure) with a conical base 2 and a pipe 3 equipped with an electromechanical valve 4, while the pipe 3 is designed to be sealed in a hole made in the reactor lid (the reactor lid is on not shown in the figures). A gas burner 5 is fixed inside the housing, powered by a container with natural gas, equipped with an electromechanical gas flow regulator 6 and an automatic piezoelectric ignition unit 7, as well as a gas detector 8 for detecting harmful components, in particular carbon monoxide, in the gases released from the reactor.

As an electromechanical gas flow regulator 6, a pressure (inlet) or gas flow regulator model RRG-15 can be used ¹ ( ¹ Pressure (input) or gas flow regulators RRG-15 with an additional pressure sensor // TP. Eltochpribor. URL : https://eltochpribor.ru/elementnaya-baza/regulyatory-elektronnye-massovogo-raskhoda-gaza-modeley-rrg-20-rrg-18-rrg-15-rrg-12-rrg-10/regulyatory-davleniya-po -vkhodu-ili-raskhoda-gaza-rrg-15-s-dop-datchikom-davleniya-dn-4-mm-36-360-i-/ (date of access: 03/05/2022)., equipped with digital and analogue controls inputs and equipped with an additional pressure sensor. The regulator is designed to supply gases to process equipment and is integral with the mounting pipe with a nominal diameter of DN 4 mm. The maximum gas pressure at the regulator input is 0.5 MPa, and the accuracy of gas pressure regulation does not exceed 2.5%.

The electromechanical valve 4, the electromechanical regulator 6 and the automatic piezoelectric ignition unit 7 are connected, respectively, to the power outputs 9, 10 and 11 of the control unit for the gas release and afterburning unit, and the measuring input 12 of the mentioned unit is connected to the output of the gas detector 8. Power outputs 9, 10, 11 of the control unit are made on the basis of transistor switches, and the control unit is fixed on the outer surface of the housing 1, is made on the basis of a microcontroller 13 and is equipped with a radio module 14 for exchanging data with a remote automated process control system (APCS).

The microcontroller 13 of the control unit includes a microprocessor core 15, connected via a system bus to the following peripheral devices of the microcontroller [7]:

• FLASH program memory 16, which stores the control program of the microcontroller;

• SRAM data memory 17, used for temporary storage and buffering of data necessary for the operation of the control program;

• multichannel analog-to-digital converter (ADC) 18, to the zero line of which the output of the gas detector 8 is connected to the zero line through an operational amplifier, which is the measuring input 12 (the lines of peripheral devices are usually numbered from zero); the remaining lines of the analog-to-digital converter are left as a reserve to allow the connection of additional sensors, for example a flue gas temperature sensor;

• LCD interface module 19, to which a TFT display 20 is connected, which is used to display the current state of the control unit and the values of the content of harmful components in the gas mixture measured by it;

• the first 21, the second 22 and the third 23 universal eight-bit GPIO I/O ports, while the power output 9 is connected to the zero line of the first 21 GPIO port, connected to the electromechanical valve 4, the power output is connected to the first line of the first 21 GPIO port 10, connected to the electromechanical regulator 6, and the second line of the first 21 GPIO port is connected to the power output 11, connected to the automatic piezoelectric ignition unit; a push-button keyboard 24 is connected to the second 22 GPIO port, containing sixteen keys, intended for setting the operating parameters of the control unit, and the third 23 GPIO port is left as a reserve;

• universal• universal synchronous-asynchronous a transceiver (USART) 25 connected to a radio module 26, which is used to receive control commands from a remote automated process control system (APCS) and transmit telemetric information to the said system about the quantitative content of carbon monoxide in the flue gases;

• SD card interface module 27, to which an SD card 28 is connected and electrically connected to it, which is used for permanent storage of the operating settings of the control unit, as well as the results of measurements of the content of harmful components in the gas mixture for their use in analyzing the efficiency of the unit.

As a microcontroller 13, it is advisable to use a single-chip computer (SOC) based on the Cortex-M4F/R microprocessor core, aimed at creating high-performance real-time hardware and software systems for critical applications. The domestic microcontroller K1921VK01T ² can be used as such an electronic computer; As a radio module, the LoRa WLK01S78-TH ³ assembly based on the SX1278 chip with a UART interface can be used, designed for exchanging information via an interference-free radio channel over long distances, and as a TFT display, the RPI LCD ² module ( ² 3.2 inch RPi LCD// ChipDip.ru URL: https://www.chipdip.ru/product/3.2inch-rpi-lcd-b (date of access: 03/05/2022).) with a resistive touch screen and a diagonal of 8.1 cm.

The gas release and afterburning unit operates as follows.

Previously, pipe 3 of housing 1 of the gas exhaust and afterburning unit is hermetically sealed in a hole made in the lid of the chemical reactor. Next, the control unit of the device is activated and, using the push-button keyboard 24 and the TFT display 20, the microcontroller is pre-configured, including setting the sampling frequency of the gas detector 8, time intervals for waiting for commands from the remote automated process control system (APCS) and transmitting it received from detector 8 telemetric information about the amount of carbon monoxide contained in the flue gases. The specified parameters are saved on SD card 28 and are used by the microcontroller to control the nodes of the control unit in the automatic operation mode of the device.

After setting up the control unit, it is switched to automatic operation mode, while the TFT display 20 and keyboard 24 can be disconnected from the control unit of the gas exhaust and afterburning unit to ensure the safety of the latter. When the device is operating, the electromechanical valve 4 is normally closed and prevents the exhaust gases from leaving the reactor. Microcontroller 13 of the control unit, based on the control program stored in its FLASH memory of programs 16, uses a radio module 26 to listen to the air and await control commands from a remote automated process control system. When receiving a command to release gases, microcontroller 13, using the zero line of GPIO port 21 through power output 9, activates electromechanical valve 4, opening it. After opening the valve, the microcontroller 13 begins, using the measuring input 12, iteratively, at regular intervals of time, counted using sixteen-bit timer-counters of the microcontroller, to interrogate the gas detector 8 using an analog-to-digital converter 18, buffering the received data in the SRAM data memory 17.

Exhaust gases, which are products of chemical reactions, begin to flow from the reactor through pipe 3 and housing 1 into the atmosphere; in the case of the presence of harmful or poisonous gases, for example carbon monoxide, in the released gas mixture, the detector 8 determines the presence of a dangerous component and generates an analog electrical signal confirming the presence of the said component, read by the microcontroller 13 using the zero line of the analog-to-digital converter ADC 18.

The microcontroller 13, based on the received signal from the detector 8 and based on the control program, makes an automatic decision on the need to burn out the dangerous gas. To do this, the microcontroller 13, using the first line of the first GPIO port 21 through the power output 10, controlling the electromechanical regulator 6, opens it, after which the gas from the gas burner enters the cavity of the housing 1. Then the microcontroller 13 using the second line GPIO port 21 through power output 11, controlling the automatic piezoelectric ignition unit 7, produces an electrical discharge in a gas environment and ignites natural gas coming from the gas burner 5 with a continuous flow of external air through the holes of the perforated housing 1. As a result of the combustion process, carbon monoxide is oxidized in the combustion zone of the burner torch to carbon dioxide and released into the atmosphere.

During the combustion of the gas coming from the burner 5, if the detector 8 detects the absence of harmful or poisonous gases in the released gas mixture, the said detector 8 generates an analog electrical signal confirming the absence of a dangerous component, read by the microcontroller 13 using the zero line of the analog-to-digital converter ADC 18.

The microcontroller 13, based on the received signal from the detector 8 and based on the control program, makes an automatic decision on the need to stop the afterburning operation of the dangerous gas. To do this, microcontroller 13, using the first line of the first GPIO port 21 through the power output 10, controlling the electromechanical regulator 6 closes it, after which the flow of gas into the cavity of the housing 1 stops, and the burner torch goes out.

Thus, the gas release and afterburning unit discussed above is a high-tech device that can be used as part of chemical reactors at industrial sites for the production of, for example, nickel carbonyl to increase the safety of work and eliminate the risk of poisoning of operating personnel with carbon monoxide.

List of sources used:

1. Karpenko G.A. On the thermal features of carbon monoxide combustion in the converter atmosphere // Modern problems of science and education. 2006. No. 5. - S. - 39-40.

2. Basic processes and apparatus of chemical technology: A manual for design / Ed. Yu.I. Dytnersky. - M.: Chemistry, 1983. - 220 p.

3. Kasatkin, A.G. Basic processes and apparatuses of chemical technology / A.G. Kasatkin; M.: State scientific and technical publishing house of chemical literature, 1961. - 830 p.

4. Voronov G.V., Goltsev V.A., Glukhov I.V. Aerodynamics and thermal state of a modern arc steel-smelting furnace // Problems of ferrous metallurgy and materials science. 2016. - No. 1. - S. - 28-34.

5. Patent US3817712A, IPC F23C9/04, F23G7/06. Smoke Abater / WENTWORTH H. ; applicant SOLA BASIC IND INC. No. 202223; application 11/26/1971; publ. 06/18/1974.

6. Patent RU2230989C2, IPC F23G7/06. Furnace for afterburning flue gases / Khlopotov Yu.P. (RU), Morozov Yu.D. (RU), Izinger Yu.V. (RU) ; applicant LLC NPO Tekhnolog; application 09/03/2001; publ. 06/20/2004. Bull. No. 17.

7. Evstifeev, A.V. Microcontrollers of the Tiny and Mega family of the Atmel family, 5th ed., erased. / A.V. Evstifeev. - M.: Publishing House “Dodeka-XXI”, 2008.- 148 p.: ill.

Claims (8)

1. A unit for the release and afterburning of gases, containing a housing with a conical base and a branch pipe equipped with an electromechanical valve, wherein the branch pipe is designed to be sealed in a hole made in the lid of a chemical reactor, characterized in that a gas burner powered from the container is fixed inside the housing with natural gas, equipped with an electromechanical gas flow regulator and an automatic piezoelectric ignition unit, as well as a gas detector for detecting harmful components in the gases released from the reactor; the power outputs of the control unit for the gas release and afterburning unit are connected to the electromechanical valve, the electromechanical regulator and the automatic piezoelectric ignition unit, equipped with a radio module, and the output of the gas detector is connected to the measuring input of the mentioned block. 2. The unit according to claim 1, characterized in that the power outputs of the control unit are made on the basis of transistor switches. 3. The unit according to claim 1, characterized in that the control unit is made on the basis of a microcontroller, which includes a microprocessor core connected via a system bus to FLASH program memory, SRAM data memory, multi-channel analog-to-digital converter, LCD module interface, universal eight-bit GPIO I/O ports, a universal synchronous-asynchronous transceiver and an SD card interface module. 4. The node according to claim 3, characterized in that a power output connected to an electromechanical valve is connected to the zero line of the first GPIO port, a power output connected to an electromechanical regulator (6) is connected to the first line of the first GPIO port, and to the second line The line of the first GPIO port is connected to a power output connected to the automatic piezoelectric ignition unit. 5. The unit according to claim 3, characterized in that a TFT display is connected to the LCD interface module. 6. The node according to claim 3, characterized in that a push-button keyboard containing sixteen keys, intended for setting the operating parameters of the control unit, is connected to the second GPIO port. 7. The node according to claim 3, characterized in that the universal synchronous-asynchronous transceiver is connected to the radio module. 8. The unit according to claim 3, characterized in that an SD card is connected to the SD card interface module and electrically connected to it.