[Ask for help] Hydrogen peroxide process description

Hydrogen peroxide industrial preparation method - air electrode for producing alkaline hydrogen peroxide and its preparation method. The present invention belongs to the field of preparing inorganic compounds by electrochemical methods. The invention relates to a quinone-containing air electrode for industrial preparation of alkaline hydrogen peroxide and a preparation method thereof. The multi-component electrode group of the present invention is assembled by unit plates. Each pair of electrodes is composed of a cathode plate, a quinone-containing air cathode carbon core, an ion exchange diaphragm, a plastic support net and an anode plate. A fluid distribution chamber and a collection chamber are provided at the upper and lower ends of the electrode working area, and a throttling hole is provided at the fluid inlet. The multi-component electrodes are connected in series with limited dipoles, and the plastic hose used for circulating alkaline water in the anode is extended to more than 5 meters. The present invention can prepare alkaline hydrogen peroxide under the condition of directly using low-pressure air and obtain satisfactory working indicators, and does not have the disadvantage that the electrode is soaked by alkaline water and becomes ineffective. 　　Quinone-containing air electrodes for producing alkaline hydrogen peroxide, characterized in that each pair of electrodes is composed of an anode plate, a plastic mesh, a cation separator and a quinone-containing air cathode, and a distribution chamber for entering fluid and a discharging fluid are provided at the upper and lower ends of the electrode working area The collection chamber has an orifice at the fluid inlet. The multi-component electrodes adopt a limited dipole series connection method. The plastic hose used for the inlet and outlet of the anode circulating alkaline water is lengthened and then connected to the liquid collection main pipe. The multi-component electrode group is assembled by the unit plate. Hydrogen peroxide industrial preparation method 2. This invention relates to the field of preparation of inorganic compounds, and in particular to a method for preparing hydrogen peroxide from the sodium peroxide aqueous solution of the cathode product obtained in the patent application No. 871 03988. Use phosphoric acid or sodium dihydrogen phosphate to neutralize the sodium peroxide aqueous solution to pH 9.0~9.7 to generate Na-[2]HPO-[4] and H-[2]O-[2]. The Na-[2]HPO-[4] ) and H-[2]O-[2] aqueous solution is cooled to +5~-5℃, so that most of the Na-[2]HPO-[4] is replaced by Na-[2]HPO- [4]·10H-[2]O hydrate is precipitated, and then the mixture containing Na-[2]HPO-[4]·10H-[2]O hydrate and peroxide oxygen aqueous solution is purified in a centrifugal separator. The hydrate is separated, and then the aqueous hydrogen peroxide solution containing a small amount of Na-[2]HPO-[4] is evaporated and fractionated to obtain about 30% H-[2]O-[2] product. This-----------------------------------------Rights: 　　A method for preparing hydrogen peroxide, characterized in that the following steps are used to prepare hydrogen peroxide from an aqueous sodium peroxide solution: (1) Use phosphoric acid or sodium dihydrogen phosphate (NaH↓[2] PO↓[4]) to neutralize the sodium peroxide aqueous solution to 9.0~9.7 to generate an aqueous solution of Na↓[2]HPO↓[4] and H↓[2]O↓[2]. (2) Cool the aqueous solution of Na↓[2]HPO↓[4] and H↓[2]O↓[2] to +5~-5℃, so that most of the Na↓[2]HPO↓[4] can be replaced by Na↓[2]HPO↓ [4]·10H↓[2]O hydrate is precipitated, (3) The mixture containing Na↓[2]HPO↓[4]·10H↓[2]O hydrate and hydrogen peroxide aqueous solution is separated in a centrifugal separator, so that Na ↓〔2〕HPO↓〔4〕·10H↓〔2]O crystal is separated from the hydrogen peroxide aqueous solution containing a small amount of Na↓〔2]HPO↓〔4], (4) Evaporate the aqueous hydrogen peroxide solution containing a small amount of Na↓[2]HPO↓[4] in an evaporator to obtain steam containing H↓[2]O↓[2] and H↓[2]O, while the Na↓[2]HPO↓ containing hydrogen peroxide is obtained. [4] The concentrated salt solution flows out from the bottom and returns to the neutralization tank. (5) The steam containing H↓[2]O↓[2] and H↓[2]O is fractionated under reduced pressure in the fractionating tower to obtain about 30% H↓[2]O↓[2] product. The third industrial production method of hydrogen peroxide uses electrolysis of 60% sulfuric acid to obtain peroxydisulfuric acid, which is then hydrolyzed to obtain hydrogen peroxide with a concentration of 95%. 　　------------------------------------------------------------------------------------------------------------------------------------------------------ 　　Package: Packed in polyethylene barrels, there should be vent holes on the lid of the container, and wrapped in a wooden box. The net weight of each barrel is 20kg. 　　Storage and transportation precautions: It is a first-class inorganic acidic corrosive product. This product should be stored in a cool, clean and ventilated warehouse. The temperature should not exceed 30°C and avoid sunlight. The container should be tightly closed, but the ventilation holes should be clear to prevent dust from clogging it, which would easily decompose and deteriorate if it falls into it. Isolate heat sources and fire, and do not store or transport together with organic matter or metals such as iron, copper, chromium and their salts. Wear work clothes, masks, and gloves when handling. If it accidentally touches the skin, rinse with water. If it touches the eyes, rinse with warm water. This product should not be stored for a long time. Inspect the product regularly and replace it promptly if a leaking barrel is found. If the dunnage wood smokes, the smoking dunnage wood should be moved out of the warehouse immediately or poured with water to save it. 　　In case of fire, water, sand or carbon dioxide fire extinguishers can be used to put out the fire.

Job and workshop processes and equipment

Hydrogen peroxide process control plan 1. Process brief 1. Process This production device contains five processes: Hydrogenation process, oxidation process, extraction and purification process, post-treatment process, and packaging process. The hydrogen sent from the outer pipe (chlor-alkali workshop) is pressurized and then sent to the hydrogenation kettle to undergo a hydrogenation reaction with the working fluid. The obtained hydrogenated liquid reacts with oxygen. The obtained oxidation liquid (including working fluid and hydrogen peroxide) is extracted and separated to obtain hydrogen peroxide, and the working fluid is regenerated and recycled. The hydrogenation process converts anthraquinone into anthrahydroquinone or * * Anthraquinone. The oxidation process uses oxygen in the air to directly oxidize anthrahydroquinone and * * to anthrahydroquinone and converted into anthraquinone, * * Anthraquinone is converted into hydrogen peroxide. The function of extraction is to use deionized water to extract and recover hydrogen peroxide from the oxidation solution to produce a hydrogen peroxide solution of a certain concentration. After the solution is purified, it not only reduces the content of organic carbon, but also produces 27.5~35% products for sale on the market. The raffinate from the extraction undergoes post-processing and regeneration before entering the next cycle of use. 2. The characteristics and difficulties of this process are that there are many control loops, the continuity of production is very strong, there are many tower equipments, and the correlation between various parameters is serious. The characteristics of some objects belong to the electric heating furnace type, which is difficult to control. For example, the pressure of the hydrogenation kettle in the hydrogenation process. When hydrogen is introduced into the kettle, the pressure rises quickly. To lower the pressure, the hydrogenation kettle's own reaction must be relied on to absorb the hydrogen. Such objects must avoid overshooting during automatic control, otherwise it will easily cause the system to lose control. In addition, the hydrogenation tank pressure object also has positive feedback characteristics, which needs to be considered during control. 3. Process requirements for control systems a. Achieve centralized monitoring of the operations of each unit, including: Monitoring and control of physical quantities such as temperature, pressure, flow, liquid level, etc. Dynamic parameter detection and control must be accurate and reliable. b. Necessary remote control measures. For emergencies such as power outages, the system should take corresponding protective measures to ensure remote control of some key control points (valves, motors, etc.) in emergencies or when needed. c. Configure necessary alarms and interlocks. d. Record important parameters and conveniently check their real-time trends and historical trends. e. The relevant parameters of relevant units or the operation of important equipment can be monitored at any time. f. The control system is simple to operate, easy to set and adjust parameters, easy to operate, and has a humanized operation interface. g. The operator station displays the entire production process, and can modify and print various relevant parameters. 2. System composition 1. System configuration The control system of this project uses FB-2000NS DCS. The system can implement multiple control algorithms such as continuous control, batch control and logic control. Based on the process flow chart with control points, we carefully analyzed the control requirements of the production process with the process technicians, and rationally designed a flow chart screen that is convenient for operators to monitor and operate. This project uses one control station and one operating station. The operating station and the control station are in the same central control room. The two operating stations are completely equal. Any one of the operating stations can also serve as an engineer station. The control station and operating station are connected by CNET dual redundant process control network. From the perspective of more reliable and economical production, we adopt hot standby redundancy for the main controller and CNET network communication card. Its function is that when the main board fails, the redundant board will automatically come into work to ensure that the system operates stably and reliably. The hardware configuration of its DCS is: FB-2001NS2 blocks, FB-2005NS network card 2 blocks, FB-2010NS-6 blocks, FB-SC14NS-6 blocks ； FB-2020NS-7 blocks, FB-SC20NS-7 blocks ； FB-2030NS-3 block, FB-SC30NS-3 block ； FB-2040NS-1 block, FB-SC43NS/R-1 block. This constitutes a distributed data acquisition and control system. In addition, there is a 6KVAUPS online uninterruptible power supply on site. After all analog signals pass through the isolation module, they enter the input terminal board, and all analog output signals pass through the isolation module and enter the on-site actuator. 2. DCS system scale AI: 96 AOUs: 23 DIN: 48 DOUT: 16 three-control strategies and implementation plans. This system has a total of 23 control loops. Basically, it adopts single-loop PID control, which is a conventional control scheme. We have made some optimizations in the configuration of the conventional control scheme, such as the setting of the positive and negative effects of the regulator. After consultation with the technical personnel, we adopted the method of ignoring the air opening and air closing forms of the regulating valve. The switching form of the regulating valve is set in the configuration software. In this way, the system * * Simplified setting of regulator action. For objects with relatively large parameter correlations, feedforward decoupling is appropriate. For example, in the hydrogen peroxide production process, the hydrogenation liquid storage tank is the finished product storage tank of the hydrogenation section. Its liquid level is a very critical parameter. At the same time, it is also an important parameter closely related to the stability of the working conditions from hydrogenation to the oxidation section. When the feed of the hydrogenation process increases, it is expected that the discharge of the hydrogenation liquid storage tank (that is, the feed of the oxidation process) will also increase. This can effectively ensure the stability of the liquid level of the hydrogenation liquid storage tank. Therefore, the liquid level of the hydrogenation liquid storage tank (LIC-1102) is controlled by a combination of uniform control and feedforward control, so that the continuity of production and the balance of materials in the entire system are effectively guaranteed. For objects with characteristics similar to electric heating furnaces, the adaptive PID method is used to avoid overshoot. As mentioned above, the pressure of the hydrogenation kettle is such an object. Therefore, we divide the pressure in the kettle into three sections and use different PID parameters to adjust them respectively. It can be seen that the time constant of the hydrogenation reactor pressure during the pressure increase process is very small, so we divide the pressure increase process into three stages.: (1) Low pressure stage. At this time, the pressure of the hydrogenation kettle rises very quickly, and the object is very sensitive to the adjustment effect. At this time, the adjustment effect of the regulator can be set weaker. (2) Medium pressure stage. At this time, the characteristics of the hydrogenation kettle are relatively stable and robust, and can maintain a relatively strong control effect. (3) High pressure stage. At this time, the object is very robust and insensitive to the adjustment effect. The integral effect needs to be cut off to avoid overshoot as much as possible. 1. Air flow control into the lower section of the oxidation tower. The goal of air flow control into the lower section of the oxidation tower is to ensure the stability of the air flow into the lower section of the oxidation tower. It is a very critical adjustment control. Although the single-loop PID adjustment method is also used, according to the particularity of the on-site actuator, when the output current is 20mA, the actuator state is fully closed. When the output is 4mA, the actuator is fully open and changes linearly. Therefore, a subtractor is added in front of the analog output module. 2. Air flow control into the upper section of the oxidation tower. The air flow control into the upper section of the oxidation tower is a single-loop PID adjustment control. 3. Hydrogenation tail gas flow control Hydrogenation tail gas flow control is also a single-loop PID adjustment control. Its control scheme is the same as the above air flow control scheme in the upper section of the oxidation tower. Working fluid preheater outlet temperature adjustment, hydrogenation liquid cooler outlet temperature adjustment control, hydrogenation bed top pressure control, hydrogenation liquid vapor-liquid separator level adjustment control, hydrogenation liquid storage tank level adjustment control, hydrogenation liquid flow adjustment control into the hydrogenation bed regeneration bed, oxidation tower upper section temperature adjustment control, oxidation tower lower section temperature adjustment control, oxidation liquid vapor-liquid separator B level adjustment control, oxidation tower tail gas pressure adjustment control, oxidation liquid storage tank level adjustment control, extraction The extraction liquid flow adjustment control at the tower outlet, the extraction tower interface adjustment control, the purification tower interface adjustment control, the working liquid metering tank level adjustment control, the drying tower interface adjustment control, the circulating working liquid level adjustment control, the alkali flow adjustment control at the bottom of the drying tower, and the drying tower bypass adjustment control all adopt the single-loop PID adjustment control method. Their control scheme is the same as the air flow adjustment control in the upper section of the oxidation tower. The block diagram of the control scheme is omitted. 4. Screen composition 1. It is divided into 11 screens including control screen, PID adjustment screen, hydrogenation screen, oxidation screen, extraction and purification screen, post-processing screen, packaging screen, fan and pump screen, parameter screen, historical trend 1, and historical trend 2. 2. Dynamic data: Shown at the corresponding place on the flow chart. 3. Keying of dynamic images: Make buttons on each screen to switch between them. 4. Click the corresponding regulating valve on the process flow chart to pop up the PID screen and modify the given value and output value online. 6. Reports are generated according to groups and printed within 8 hours. 7. Trends are grouped according to user requirements. All historical trends of 52 important parameters are available on historical trend screens 1 and 2. These historical data are displayed on the historical trend chart in a cycle of collecting once every second. 8. Alarm According to customer requirements, sound alarms and screen alarm prompts are used. A total of 82 parameters are set for alarm. IV. Conclusion After the system was started, powered on and debugged, the stability of key parameters such as the liquid level of the regeneration liquid tank, the hydrogenation tank pressure and the liquid level was very good, and the continuity of production and the balance of materials were well guaranteed. While reducing the labor intensity of workers, the expected results are achieved in terms of product yield, consumption and quality. The DCS system can exert its powerful and flexible functions in the hydrogen peroxide production process and achieve good economic benefits.

Hydrogen peroxide is an important chemical product. At present, its production methods mainly include electrolysis, oxygen cathode reduction, alcohol oxidation, direct combination of hydrogen and oxygen, and anthraquinone method. (1) Electrolysis method. The electrolysis method was the main method for producing hydrogen peroxide in the first half of the 20th century. This method uses Pt as the anode and lead or graphite as the cathode. The saturated ammonium bisulfate solution is electrolyzed into persulfate an, and then hydrolyzed with dilute sulfuric acid to obtain hydrogen peroxide. This method consumes a lot of energy and is limited to small-scale production. (2) Oxygen cathode reduction method. Using this method to produce hydrogen peroxide is to put a strong alkaline electrolyte in an electrolytic cell, so that the oxygen in the air is reduced to perhydroxyl negative ions at the cathode, and then converted into hydrogen peroxide in the recovery device. The process is to generate calcium peroxide with the help of calcium salt precipitation, filter and decompose it, use CO2 to decompose it to produce hydrogen peroxide, and at the same time produce calcium carbonate for recycling. This method is simple to produce hydrogen peroxide, has low cost and no pollution, but the concentration of hydrogen peroxide in the product is low. (3) Alcohol oxidation method. This method was developed by Shell and DuPont. The United States and the former Soviet Union have industrial production devices using isopropanol as raw material. In addition to isopropanol, the alcohols used in this method include cyclohexanol, 1-phenylethanol, etc., but isopropanol is mostly used, and propylene glycol is co-produced at the same time. This method does not use any catalyst and uses air to automatically oxidize hydrogen peroxide. However, the cost of steam is high, and co-production of hydrogen peroxide is generally unfavorable. (4) Direct hydrogenation with oxygen. This method uses water as the reaction medium, contains almost no organic matter, only contains a small amount of bromide as a cocatalyst, uses Pt (such as Pt/C) as the catalyst, uses hydrogen and oxygen (or air) as raw materials, and continuously reacts to synthesize hydrogen peroxide under the conditions of a reaction temperature of 0-25°C and a pressure of 2.9-19.3Mpa. The entire process of synthesizing hydrogen peroxide by this method does not produce any organic matter, and there is basically no waste. However, the selectivity for hydrogen peroxide in the product is low and the risk is high. There have been no reports of industrial production so far, but the development potential is huge. This method will be the focus of research and development in the world in the coming period. (5) Anthraquinone method. This method uses anthraquinone compounds as hydrogen carriers (or working carriers) to react hydrogen and oxygen to generate hydrogen peroxide. This method is currently the most important method for industrial production of hydrogen peroxide. Its output has an absolute advantage, accounting for approximately 95% of the world's total hydrogen peroxide production. This method is to dissolve anthraquinone derivatives (generally 2-alkylanthraquinone) in organic solvents to prepare a working solution. Most processes contain an appropriate amount of anthraquinone in the working solution. * * Anthraquinone, and then the working solution is hydrogenated in the presence of a catalyst to generate anthrahydroquinone ； In the absence of any catalyst, air or oxygen is used for oxidation to generate hydrogen peroxide and anthraquinone (recycled) ； Finally, it is extracted with pure water, refined and concentrated to obtain hydrogen peroxide of various concentrations. ； The extraction liquid is recycled after regeneration. The industrial production technology of this method is very mature, with advanced technology, high degree of automation, low cost and energy consumption, and is suitable for large-scale industrial production of hydrogen peroxide.

Non-Metal Inorganization >> Liming Chemical >> Issue 4, 1989 >> Summary of hydrogen peroxide production technology review recommendations

There are two main industrial production methods of hydrogen peroxide: electrolysis method and allium quinone method. Before the 1990s, most domestic hydrogen peroxide production companies used the electrolysis method. This method has high current efficiency, short process flow, and high product quality. However, due to large power consumption and high production costs, it is not suitable for large-scale industrial production and has been gradually eliminated. Main features of the technology: 1. Fixed bed palladium catalyst hydrogenation process ； 2. Empty tower air oxidation process ； 3. Sieve plate tower extraction process and product purification process ； 4. Trioctyl phosphate and aromatic hydrocarbon working solvents. 5. Use hydrogen peroxide to treat wastewater generated during the production process of this device to reduce sewage treatment costs, etc. ； 6. Using DCS control, the operation process is continuous and suitable for large-scale production. It also provides a reasonably short, safe and reliable process. Product technical indicators (industrial grade hydrogen peroxide) Indicator name 27.5% specification 30% specification 35% specification 50% specification H2O2 (m/m) 27.5% 30% 35% 50% Free acid (calculated as H2SO4) (m/m)% 0.04 0.04 0.04 0.04 Non-volatile matter (m/m)% 0.08 0.08 0.08 0.08 Stability% 97.0 97.0 97.0 97.0 Total carbon (calculated as C) (m/m)% 0.03 0.025 0.025 0.035 Nitrate (calculated as NO3) (m/m)% 0.02 0.02 0.02 0.025 • Product technical indicators (food additive grade hydrogen peroxide) Indicator name 30% specification 35% specification 50% specification H2O2 (m/m) 30% 35% 50% Free acid (calculated as H2SO4) (m/m)% 0.02 0.02 0.02 Non-volatile matter (m/m)% 0.005 0.005 0.005 Phosphate (PO42- ) (m/m)% 0.005 0.005 0.005 Arsenic (As) (m/m)% 0.0001 0.0001 0.0001 Heavy metal (calculated as Pb)% 0.001 0.001 0.001 Iron (Fe) (m/m)% 0.00005 0.00005 0.00005 Tin (Sn) (m/m)% 0.001 0.001 0.001

Solution for hydrogen peroxide production process 1. Overview Hydrogen peroxide, also known as hydrogen peroxide, is an important inorganic chemical product and is widely used in textile, papermaking, chemical industry, light industry, medicine, electronics, food, environmental protection and other fields. Industrial grade hydrogen peroxide can decompose slowly at room temperature. When the temperature rises or is exposed to ultraviolet rays, the decomposition rate accelerates. When it encounters dust, heavy metal ions or alkaline substances, it will decompose violently, releasing a large amount of oxygen and heat, and may explode in serious cases. Hydrogen peroxide has strong oxidizing ability, can react with various reducing substances, and is a raw material for preparing inorganic peroxides and organic peroxides. Due to its excellent oxidizing properties, hydrogen peroxide can destroy the conjugated system in organic pigment molecules and eliminate color under alkaline conditions. Therefore, it is widely used as a bleaching agent in textile, papermaking and other industries. At present, my country's hydrogen peroxide products are divided into industrial grade, reagent grade, pharmaceutical grade and electronic grade, with concentrations of 27.5%, 35%, 50% and 70%. At present, there are two methods for producing hydrogen peroxide in my country: the anthraquinone method and the electrolysis method. Before 1986, the electrolysis method was the main method of producing hydrogen peroxide in my country. Because it consumes a lot of electricity and increases the cost, it is not suitable for large-scale production and has been gradually eliminated. However, the hydrogen peroxide produced by the electrolysis method has the highest quality and can be refined into high-concentration products, which is suitable for food, medicine and other industries. The anthraquinone method is superior to the electrolysis method and has many advantages such as advanced technology, high degree of automation, large production capacity, low cost and energy consumption, and easy management of "three wastes". After 1987, the production of hydrogen peroxide using the anthraquinone method has exceeded that of the electrolysis method. The anthraquinone method is divided into nickel catalyst method and palladium catalyst method according to the different catalysts used. The production of hydrogen peroxide by both methods requires a series of processes such as hydrogenation, oxidation, extraction, regeneration, and purification. The biggest difference between the two is that the former uses a nickel catalyst suspended bed hydrogenator, while the latter uses a palladium catalyst fixed bed hydrogenator. Compared with the former, the latter has the advantages of short process flow, simple hydrogenation equipment, long service life of the catalyst, safety and reliability, and easy operation, so it has stronger competitiveness. By the end of 1999, there were 51 hydrogen peroxide production enterprises in China, with about 66 sets of production equipment, basically anthraquinone production equipment, of which the palladium catalyst fixed-bed hydrogenation process is the most important production process. Hydrogen peroxide production is developing very rapidly, and it tends to develop in the direction of large-scale, high-tech, and automated control. Among them, the application of DCS distributed control system has become more and more extensive and important. 2. Systematic process flow The production process of hydrogen peroxide consists of five processes.: Hydrogenation process, oxidation process, extraction and purification process, post-treatment process, working fluid preparation and recovery process: The hydrogenation process converts anthraquinone into anthrahydroquinone or * * Anthraquinone. The oxidation process uses oxygen in the air to directly oxidize anthrahydroquinone and * * to anthrahydroquinone and converted into anthraquinone, * * Anthraquinone is converted into hydrogen peroxide. The function of extraction is to use deionized water to extract and recover hydrogen peroxide from the oxidation solution to produce a hydrogen peroxide solution of a certain concentration. After the solution is purified, it not only reduces the content of organic carbon, but also produces 27.5 to 35% of the product for sale in the market. The extracted raffinate undergoes post-processing and regeneration before entering the next cycle of use. The production process is shown in the figure below: 3. Control scheme According to the production process of hydrogen peroxide, the control system implements the following functions: 1. Achieve centralized monitoring of the operations of each unit, including: Monitoring and control of physical quantities such as temperature, pressure, flow, liquid level, etc. Dynamic parameter detection and control must be accurate and reliable. 2. Necessary remote control measures. For emergencies such as power outages, the system should take corresponding protective measures to ensure remote control of some key control points (valves, motors, etc.) in emergencies or when needed. 3. Configure necessary alarms and interlocks. 4. Record important parameters and conveniently check their real-time trends and historical trends. 5. The relevant parameters of relevant units or the operation of important equipment can be monitored at any time. 6. The control system is simple to operate, easy to set and adjust parameters, easy to operate, and has a humanized operation interface. 7. The operator station displays the entire production process, and can modify and print various relevant parameters. Several typical control strategy configurations in hydrogen peroxide production equipment: Ⅰ. Hydrogenation tower pressure maximum value and inlet flow cascade adjustment control strategy configuration: As shown in the figure, PIC102, PIC103, and PIC104 are the top pressures of the upper, middle, and lower towers of the hydrogenation tower respectively. The process operation process is that every two tower sections are used in series. It is required that the maximum pressure of the three-section tower is adjusted in series with the hydrogen flow rate FT101 into the hydrogenation tower. According to the characteristics of the process, the MAX function module is introduced and the soft connection of the function module provided by DCS is used, so that it is easy to control the regulating valve FN101 under different circumstances. Ⅱ. Extraction tower interface liquid level and inlet water flow cascade adjustment control strategy configuration: A cascade regulation system is put into operation in this device. The advantages of DCS soft connection are used in the configuration to allow free switching between manual-automatic and cascade. Single-circuit regulation is used during startup. After the production is stable, the operator can easily switch to cascade regulation. Operate MAN-AUTO-CAS at the operating station to conveniently switch the soft connection. The adjustment quality is high and the operation is simple. The configuration plan is as shown below: Ⅲ. Parameter accumulation, temperature and pressure compensation calculation: 　 For example, if the steam flow rate needs to be accumulated, add the module - "STAT" accumulation calculation module during configuration. ； The air flow is measured using an orifice plate, so a DCS soft connection is used to introduce pressure compensation (the temperature is relatively stable). Ⅵ. Valve position setting: 　 Due to process safety requirements, control valves have air-opening and air-closing types. During use, it was discovered that operators and instrument workers must know the mode of each valve, air-opening or air-closing, before they can set up manual operation. This added difficulty to the operation. Later, it was introduced in the control configuration and the INV function block, such as the FN-401 valve, is air-closed. Add the INV function block and write the expression, OP=100-PID2. When the OP air-closed valve outputs 100% signal, the valve position is fully closed. After configuration, the operation is the same as the air-open valve. When the operating signal is 0%, it is fully closed, and when it is 100%, it is fully open, making the operation convenient and simple. At the same time, the positive and negative action settings of the adjustment do not need to consider the positive and negative actions of the valve, and can ensure that the system is in a safe valve position when the air source fails. At the same time, the function block is used to set the parking operation button. When the power equipment has an emergency, the operator only needs to click the parking button, and all the regulating valves will be set to the safety valve positions according to the process requirements to ensure production safety. Moreover, when the control point is a loop failure, such as on-site transmitter failure or circuit breakage, it provides safety guarantee. The control output can be set for hold, fully open output, fully closed output, safe value output, etc. ； Alarms for abnormal process changes can also be set. ； Limiting the tiny jitter of the control output can eliminate the violent jitter of the control valve at one position, improve the control quality, and extend the life of the control valve. 4. System configuration According to the requirements of the hydrogen peroxide production process and control scheme, we have configured a safe and reliable SunyTDCS9200 distributed control system to supervise, control and optimize. SunyTDCS9200 distributed control system realizes process control, logic control, sequence control and other functions ； With modular flexible design ； Provide open data interface, fieldbus and Internet access ； Complying with the development trend of the times, it absorbs the latest electronic technology, network technology, and control technology. It has the characteristics of high reliability, open system, flexible structure, friendly interface, powerful functions, and easy maintenance. 1. The system structure is shown in the figure below: 2. System control detection point: This system has many analog quantity detection points such as temperature and liquid level, which are approximately: There are 39 thermal resistors, 98 4-20mA analog inputs, 48 ​​4-20mA analog outputs, 48 ​​control loops, and 26 switch inputs. 3. System hardware configuration: When configuring the system hardware, it is necessary to have an overview of the overall situation, including meeting the control requirements of the production process, the characteristics of components such as on-site transmitters and actuators, transmission signal cables and DCS input/output templates, etc., and conducting a comprehensive analysis from the rationality of the process, the economy of investment, the reliability of operation, the convenience of maintenance, etc. 3.1 Redundant system server/operating station, equipped with 1 engineering station and 1 operating station, and reserved PC interface to meet the operation needs of the system. Install the operating station software on the engineering station. It can be used as an operating station when the system is running. When the system is started, the two operating stations participate in the operation at the same time. 3.2 Redundant high-performance control template, hot backup between the two control templates, accepting network data at the same time, if one of the controllers fails, the backup controller automatically enters the working state. Complete functions such as adjustment control, data processing, logic interlocking, and equipment control. 3.3 Redundant Ethernet and control network, the system is configured with 2 networks, and the monitoring layer is required to be open. The data communication system connects distributed processing units, input/output processing systems, engineering stations and operating stations to ensure reliable and efficient system communication. Therefore, redundant Ethernet configuration is adopted, the communication protocol is TCP/IP standard protocol, and the control network requires security. 3.4 In terms of I/O module configuration, more than 15% of the expansion space is reserved, and the types of modules are kept to a minimum. There are only 3 types of I/O modules in the entire system, thus reducing the types and costs of spare parts. 3.5 All power supply equipment and components are redundant. 3.6 System configuration table: Model Specification Name Unit Quantity 1. Control software part ST9432 SunyTech system software package (2048-point development and running version) set 1ST9435 SunyTech system software package (2048-point running version) set 1ST9441 Windows2000 Professional operating system (authorized version) set 2 2. Operation station and engineer part ST961221 "engineer station/operator station (mainstream configuration) (including operation console/host/monitor/communication template/keyboard) set 2 ST9603 printer platform set 1ST9662 laser printer A4 (Black and white) Taiwan 1 Three, on-site control station ST9002 standard cabinet (2 meters) Taiwan 2 ST9004 communication cable cover 1ST9005 cabinet accessory cover 2ST91116U industrial standard cage platform 2ST9121 bus bottom plate block 2ST9132 power supply component block 4ST9133 cooling component block 2ST913424VDC power supply component block 2ST9161 control module Plate 2ST927116-32-channel universal conditioning module block 15ST9315 single-channel fully isolated universal AI module block 158ST9321 single-channel fully isolated current AO module block 56ST9331 dual-channel optical isolation DI module block 15ST91728-channel AIO/16-channel DIO universal transfer terminal block 27ST917316-channel switching input transfer terminal block 2 4. System functions: 4.1 Engineering station function 4.1.1 is used for program development, system diagnosis, control system configuration, database and screen editing and modification. 4.1.2 Generate any display screen and trend chart, etc., and can call up any defined system display screen in the system for modification and other work. 4.1.3 Through the communication bus, the system configuration information and related data of any distributed processing unit in the system can be retrieved. Configuration data can be downloaded from the engineering station to the control stations of each distributed unit. In addition, the system can automatically refresh its memory after the reconfigured data is confirmed. 4.1.4 It has offline and online full code download functions, which does not affect the normal operation of the dedicated security. Network equipment can be added or removed online without affecting the normal operation of other network equipment. 4.1.5 It has the function of monitoring the operating status of the DCS system. Including monitoring of the operating status of each control station, the operating status of each operating station, and network communication status at all levels. 4.1.6 has online configuration function. like: Changes in the upper and lower limits of the measuring range, adjustment of control parameters, etc. 4.1.7 It has the ability to display online the values ​​of all input/output and intermediate quantities on the configuration diagram. 4.1.8 The engineering station sets an operation protection password to prevent unauthorized changes to control strategies, applications, and system databases. 4.2 Operator station function The operator station is the interface for human-machine dialogue, where almost all control instructions and status parameters are exchanged. The operation station can display various on-site process parameters on each flow chart, control the drive device, switch control modes, adjust process set values, etc., monitor every analog and digital quantity in the system, display and confirm alarms, operation guidance, record operation logs, record operation information such as changing set values, manual/automatic switching and time, etc., display historical trend charts, and print reports regularly. The operation is simple and meets the requirements of operation control and production management. 5. Summary Using the SunyTDCS9200 decentralized centralized control system in the hydrogen peroxide production process can achieve: The control is accurate and reliable, simple to operate, easy to maintain, save labor, improve product quality, reduce consumption, and create considerable economic and social benefits for enterprises. This post was last edited by jhff on 2009-4-5 22:43 ]

A brief introduction to the hazard evaluation and countermeasures of hydrogen peroxide production process author: Through the investigation of domestic active hydrogen peroxide production equipment, combined with the situation of other domestic and foreign hydrogen peroxide manufacturers, the dangerous and harmful factors that may occur in the production process are analyzed and pointed out, and corresponding countermeasures are proposed to provide reference for enterprise fire accidents and safety production. 　　1 Introduction Hydrogen peroxide (hydrogen peroxide, H2O2) can be produced by electrolysis, isopropyl alcohol and anthraquinone. The anthraquinone method has been widely developed in recent years because the raw materials are simple and easy to obtain and it saves a lot of energy consumption. However, there are still many dangerous factors in the production process of anthraquinone dioxide. Once an accident occurs, it may cause extremely serious consequences. I conducted a survey on an active hydrogen peroxide device in China, and also reviewed domestic and foreign hydrogen peroxide production information and information. * * Production specifications and standards, after being discussed by relevant experts, identify and evaluate the dangerous and harmful factors that may be encountered in the production process of hydrogen peroxide, and propose corresponding countermeasures. 　　2 Brief description of hydrogen peroxide plant process Hydrogen peroxide production adopts anthraquinone method palladium catalyst fixed bed hydrogenation process. This method uses heavy aromatic hydrocarbons and trioctyl phosphate as solvents and 2-acetanthraquinone as solute to prepare a working liquid. The working liquid and hydrogen are catalyzed by the action of palladium agent. After hydrogenation, a hydroanthraquinone solution is obtained, which is the hydrogenation liquid. The hydrogenation liquid is oxidized by air to obtain a mixture of H2O2 and anthraquinone, which is the oxidation liquid. The oxidation liquid is extracted to separate H2O2, and then purified into qualified H2O2 (27.5%). The shared anthraquinone solution is post-processed to remove the entrained H2O2 and returned to the hydrogenation process as a working fluid. The dilute product H2O2 can also be concentrated into concentrated product H2O2 through rectification. During the entire process, the working fluid composed of anthraquinone, aromatic hydrocarbons and trioctyl phosphate is recycled, with only a small amount of process loss. The main material consumption is hydrogen, a by-product of the plant's ammonia synthesis system, and the electricity consumption is all power consumption. Therefore, it has the advantages of simple raw materials and low energy consumption. Its process flow chart 1. Figure 1 Simple process flow chart for hydrogen peroxide production Figure 2 Analysis of dangerous and harmful factors The fire hazard classification of hydrogen peroxide production is classified as Class A according to the requirements of Article 3.1.1 of the "Code for Fire Protection Design of Buildings". The raw materials hydrogen and heavy aromatic hydrocarbons produced are well-known flammable and explosive substances, and its product hydrogen peroxide is a strong oxidant. The dangerous and harmful substances involved in the production process are of many varieties and large quantities. It can be said that this process uses dangerous raw materials to produce dangerous products. Therefore, the main risk factors in hydrogen peroxide production are fire and explosion, as well as poisoning, corrosion and other dangerous and harmful factors. 　　2.1 Analysis of hazards and hazardous factors in the production process This process uses flammable substances such as aromatic hydrocarbons, trioctyl phosphate, and hydrogen. Under the action of a catalyst, hydrogen peroxide with strong oxidizing properties is generated through a chemical reaction. Under normal circumstances, H2O2 is not allowed to be together with organic combustibles. This device uses working fluid and hydrogen together to obtain a hydrogenated liquid through a catalytic hydrogenation reaction. The latter then undergoes an oxidation reaction with oxygen in the air to reduce the hydroanthraquinone in the solution to the original anthraquinone and generate hydrogen peroxide at the same time. Although the process is operated under controllable conditions, there are objectively unsafe factors in production. 　　When 2-ethylanthraquinone in the working fluid is catalytically hydrogenated, certain side reactions will occur under acidic conditions, and hydrogen peroxide will be generated during oxidation. Hydrogen peroxide will accelerate decomposition under alkaline conditions. Therefore, it is required to maintain weak alkalinity in the hydrogenation process and acidity in the oxidation process to maintain the effective service life of anthraquinone and the stability of hydrogen peroxide. It is also required to maintain alkalinity in the post-processing process to decompose the hydrogen peroxide entrained in the circulating working fluid. Improper operation will cause acid and alkali substances to mix, causing danger. 　　The strong oxidizing properties of hydrogen peroxide during use are exactly the shortcomings that need to be prevented in production, that is, it requires that no "related" substances be mixed in production. This places stringent requirements on the entire set of production equipment, packaging materials and even storage and transportation equipment. It is this contradiction between the production and use of H2O2 that brings certain difficulties to safe production. 　　2.1.1 Hydrogenation reaction: In the hydrogenation process, a palladium catalyst is used in the fixed bed to catalyze hydrogenation, and in the hydrogenation liquid regeneration bed, alkaline alumina is used to regenerate the anthraquinone degradation products. Under abnormal circumstances, the palladium catalyst or alumina may enter the subsequent process with the working fluid, resulting in mixed decomposition of hydrogen peroxide. 　　The hydrogenation reaction is a reduction reaction and an exothermic reaction. This process uses catalytic hydrogenation. Although it has the advantages of simple process, low consumption, and less waste, it has high requirements for equipment and operations. In addition, the hydrogenation reaction involves hydrogen, air (when driving) and active catalysts, which are conditions for explosion. If you are not careful during the production operation, mix the three at the same time, or do not pay attention to the replacement or improper replacement of nitrogen, air, and hydrogen, danger will occur. 　　2.1.2 Oxidation reaction Oxidation reaction is an exothermic reaction, and hydrogen peroxide decomposes when exposed to heat. This is a contradiction. If the material ratio is out of balance and the temperature is improperly controlled, it is easy to explode and catch fire. The oxidation process adopts air liquid phase oxidation process. Although this process has the advantages of rich sources of oxidants and high production efficiency, it is not safe. This is mainly reflected in the oxidation reaction and conditions, because the oxidation of hydrogenated liquid with air is a gas-liquid phase reaction. The diffusion rate of the gas phase into the liquid phase is slow, and due to the limitation of oxygen content in the air, the reaction speed is affected. Although increasing the temperature is beneficial to the progress of the reaction, it is not conducive to the absorption of oxygen in the air by the hydrogenated liquid. This is another contradiction. In addition, the oxidation reaction is an exothermic reaction. If the heat of reaction is not removed in time, the temperature will be too high, causing an explosion. The solution is to increase the air pressure (or air speed) to increase the reaction speed, which increases unsafe factors. If the amount of air entering is large, oxygen will not be completely absorbed in the reactor, causing the oxygen content in the exhaust gas to increase and reach the explosion limit concentration range. An explosion will occur when sparks or shocks occur. 　　2.1.3 In the extraction process, whether the extraction liquid discharged from the top of the extraction tower can seal the backflow alkali liquid from the alkali drying tower in the post-processing process is the greatest guarantee of safety. Once the alkali liquid in the drying tower flows back to the extraction tower, it will cause the hydrogen peroxide in the extraction tower to rapidly decompose, release oxygen, and sharply increase the pressure in the tower. In the mild case, the extraction liquid will emerge from the vent pipe at the top of the tower, and in severe cases, the extraction tower will burst. 　　The content of hydrogen peroxide in the extraction solution not only directly affects the output, but also affects the safe operation of the post-processing process. When the hydrogen peroxide content is high, the load on the drying tower in the post-treatment process increases, and more oxygen is released after being decomposed by the alkali solution in the tower. It is unsafe whether it is discharged into the atmosphere or the drying tower equipment itself. Generally, the hydrogen peroxide content in the raffinate is controlled at about 0.7%. 　　The quality of pure water used for extraction is related to the stability of the product. Its conductivity is generally controlled at no higher than 6×10-6S/m. In particular, heavy metal ions in the water must be removed, because heavy metal ions can promote the decomposition of hydrogen peroxide. 　　2.1.4 Concentration process When concentrating, appropriate stabilizers must be added, evaporation and distillation temperatures and pressures must be controlled, and the evaporation residual liquid in the system must be cleared in a timely manner. Explosions caused by the evaporation residual liquid in the system not being cleared in time are also a major accident hazard for hydrogen peroxide production companies. Pure H2O2 is relatively stable, but when mixed with impurities such as heavy metals and their salts, alkali, organic matter, dust, etc., it will promote the decomposition of hydrogen peroxide. Its decomposition rate increases with the increase of temperature, and violent decomposition can cause an explosion. In order to prevent this phenomenon from happening, vacuum is used in the process to lower the distillation temperature, which increases the difficulty of operation. If the system leaks, external impurities can easily invade. In addition, excessive temperature or pressure is detrimental to product concentration and safety. 　　2.1.5 Working liquid post-treatment process The raffinate discharged from the top of the extraction tower contains a small amount of hydrogen peroxide (0.7%) and water. If it is directly returned to the hydrogenation system for use, it will cause hydrogen and oxygen to mix in the hydrogenation tower to form an explosive mixture. When the oxygen content reaches the explosion range, an explosion will occur. Therefore, hydrogen peroxide and water must be removed in this process. 　　2.2 Hazardousness of Raw Materials Many raw materials in device production are flammable, explosive, toxic and harmful substances, such as heavy aromatic hydrocarbons, trioctyl phosphate, anthraquinone, etc., which are both flammable and toxic. Hydrogen is a well-known flammable and explosive substance. These substances In addition to the dangers of materials themselves, the harm they bring to production is often caused by mixing, entrainment and leakage. Although some materials such as palladium catalysts, activated alumina, air, and impurities are not dangerous in themselves, they can cause accidents if they are accidentally entered into the system. 　　Dangerous parts: Raw material storage area, working fluid configuration, hydrogenation tower, post-processing process, packaging area, etc. 　　2.3 Product dangers The dangers of hydrogen peroxide are mainly reflected in the following three aspects:: 　　2.3.1 Combustion Explosive hydrogen peroxide is most stable when the pH is 4±0.5, is easily decomposed in alkaline solutions, and can also decompose under strong light, especially short-wave rays. Its decomposition rate is about 1% per week at 65°C ； About 2% per day at 100°C ； It decomposes rapidly and explodes at 140℃. Its explosion limit is 25% to 100%. For more than 74% hydrogen peroxide, the upper limit can reach 26%. When encountering an electric spark, a gas phase explosion will occur. However, its actual explosion risk is mainly due to its reaction with organic matter or explosion due to catalytic decomposition of impurities. The mixture it forms with many organic substances such as sugar, starch, alcohols, petroleum products, etc. is sensitive and can explode under impact, heat or sparks. Hydrogen peroxide itself is non-flammable, but it can react with combustibles and generate enough heat to cause a fire. The oxygen released by its decomposition can strongly support combustion and eventually lead to an explosion. Therefore, special attention should be paid to fires. 　　2.3.2 Corrosive hydrogen peroxide is corrosive to a certain extent and will promote its decomposition depending on the material. The following materials are generally used in industry: Metal materials can use aluminum, stainless steel, lithium, and zirconium with a purity of more than 99.5%. Ordinary steel, copper, copper alloys, lead, and titanium cannot be used. Plastics can be hard and soft polyvinyl chloride, etc., and non-metallic materials can be glass and ceramics. 　　2.3.3 Toxicity Its toxicity is mainly caused by its active oxidation, such as chemical burns to the eyes, mucous membranes and skin, and ignition of ordinary clothing. Hydrogen peroxide can cause poisoning through respiratory inhalation, skin contact, absorption and swallowing. However, its vapor pressure is low and its volatility is low, so the possibility of inhaling the vapor poisoning is small, and it has a strong burning sensation, so the possibility of swallowing it is also very small. It is mainly a burn caused by skin contact, which causes local skin and hair to turn white (but can recover after a period of time), causing stinging and itching. Depending on the amount of contact, time, and site of action, chemical burns may occur to varying degrees. After penetrating into the stratum corneum of the skin, it decomposes to produce oxygen, causing the epidermis to blister. The stratum corneum on the palms, fingertips, and nail beds is thicker, and the peripheral nerves are abundant. The pain is more severe and unbearable. Patients often become restless, irritable, and have difficulty falling asleep. Large doses and not timely flushing can leave permanent scars. Vapor irritates eyes, symptoms disappear quickly after contact is removed ； Droplets splashing into the eyes can cause conjunctivitis, iridocyclitis, corneal epithelial degeneration, necrosis and turbidity, affecting vision or leading to complete blindness. 　　The locations where the explosive, corrosive and toxic properties of hydrogen peroxide exist include:: Oxidation tower, extraction tower, purification tower, drying tower, post-treatment process, concentration, packaging, storage tank area, etc. 　　2.4 Common Injuries 2.4.1 Electric Shock Injury Devices include material pumps, fans, air compressors, electric hoists and other electrical equipment. If an accident occurs to the electrical equipment or the electrical installation is not standardized, there is a lack of grounding or zero connection, or the ground connection is damaged and fails, electric shock accidents will occur. Temporary lines laid along walls or along the ground have no protective sleeves or have damaged insulation. Electric shock may occur if they come into contact with the human body. Because the device uses a low-voltage power supply, any electric shock will appear as a low-voltage electric shock. Power distribution rooms, hydrogenation towers, oxidation towers, extraction towers, purification towers, drying towers, post-treatment processes, concentration, packaging, storage tank areas, fire pump rooms, etc. are places with greater risks. 　　2.4.2 Static electricity lightning hazard Hydrogen and heavy aromatic hydrocarbons, the raw materials used in hydrogen peroxide production, are flammable and explosive substances. They are prone to generate static electricity during the pipeline process. If there is no static electricity jumper grounding device or it fails, there is a risk of fire or explosion in the system caused by static electricity accumulation and discharge. In particular, the minimum ignition energy of a mixture of air and hydrogen is only 0.017mJ, which is easily ignited by static sparks. 　　If the device lacks lightning protection facilities or the lightning protection facilities are poorly grounded or the grounding resistance is too large, it may be struck by lightning or lightning induced discharge. Therefore, lightning protection facilities must be installed in production plants, warehouses, etc., and inspections and tests must be carried out on time to ensure that the lightning protection facilities are intact. The grounding resistance of equipment pipelines should be within the specified range to avoid losses caused by lightning induction. 　　2.4.3 Falling from high altitude and impact of falling objects from high altitude The hydrogenation tower, oxidation tower, extraction tower, purification tower, drying tower, post-treatment process, concentration tower, etc. in the hydrogen peroxide device have platforms, ladders, high-level electric hoists or maintenance scaffolding, etc. Employees are at risk of falling from high altitude and being struck by high objects during cross-operation and maintenance operations. 　　2.4.4 Noise damage: There are air compressors, pumps and other rotating equipment in the hydrogen peroxide device. If there is a malfunction or poor lubrication, or if it is operated nearby for a long time, noise damage will occur. In positions with loud noise, operators must wear earmuffs to reduce noise hazards. 　　2.4.5 Mechanical injury There are a variety of liquid pumps, compressors and other rotating equipment in the hydrogen peroxide device, and there is a risk of mechanical injury. 　　3 Use "Dow Fire and Explosion Hazard Index Evaluation" (Seventh Edition) to evaluate 3.1 Division of process units According to the process flow and equipment layout of 50,000 t/a hydrogen peroxide production, this device is divided into the following 7 units: Preparation, hydrogenation, oxidation, extraction, post-treatment, concentration, packaging, 3.2 Calculation of unit inherent hazard index 3.2.1 Determination of material coefficient Table 1 Determination of hazardous substances in unit Evaluation unit Remarks on hazardous substances determined Preparation of heavy aromatic flammable liquids, poor stability under heating and pressure Hydrogenation of H2 Flammable and explosive gases, very stable in the absence of oxygen. Oxidized aromatic hydrocarbon vapor + oxygen flammable mixed gas may explode in a closed state. Heavy aromatic hydrocarbons + dilute H2O2 may be extracted. Combustible liquids. Not stable enough under non-heating and pressure. Post-processing of heavy aromatic hydrocarbons + less H2O2. Combustible liquid (gas). Poor stability under heating and pressure. Concentrated H2O2. Incombustible materials. May explode in a closed state. Packed with concentrated H2O2. From the "Dow" material coefficients and properties table, through correction and table lookup, the parameters of the following materials are shown in Table 2. Table 2 Substance coefficients and properties table Substance name Substance coefficient MF Combustion heat (kJ/kg) NFPA classification health hazard NH Flammability NF Chemical activity NR Heavy aromatics 14 0.14×105 2 0 3 H2 21 1.20×105 0 4 0 Aromatic hydrocarbon vapor + oxygen 29 0.41×105 2 2 3 Heavy aromatics + dilute H2O2 24 0.41×105 2 2 2 Heavy aromatics + less H2O2 14 0.41×105 2 2 1 Concentrated H2O2 29 2 0 3 3.2.2 Calculation results According to the principle of selecting process unit hazard coefficients in "Dow", the general process hazard and special process hazard were calculated for the above 7 units respectively. The results are shown in Table 3. Table 3 Production unit fire and explosion hazard index calculation table unit preparation hydrogenation oxidation extraction post-treatment concentrated packaging material coefficient (MF) 21 21 29 24 14 29 29 1. General process hazard coefficient (F1) 1.95 2.50 2.85 1.70 1.70 2.35 1.70 2. Special process hazard coefficient (F2) 1.80 2.55 3.85 2.00 2.00 2.50 2.00 3. Process unit risk coefficient F3= (F1×F2) 3.51 6.38 10.97 3.40 3.40 5.87 3.40 4. Fire and explosion index F&EI= (F3×MF) 49.1 134.0 232.0 81.6 47.6 170.2 98.6 5. Unit damage coefficient 0.52 0.75 0.93 0.67 0.46 0.83 0.75 6. Exposure radius (m) 12.6 34.7 59.4 20.9 12.2 43.6 25.2 7. Risk level: lightest, very large, very large, lightest, lightest, very large, medium Note: If the oxidation unit F3=10.97 is greater than 8, it will be counted as 8. 　　Editor's Note: Due to one-sided limitations, the intermediate processes in the above table have been deleted, and only the results are retained. Table 4 F&EI value and hazard level F&EI 1～60 61～96 97～127 128～158 ≥159 Hazard coefficient: lightest, light, medium, very large, very large 3.3 Calculation of hazard index after unit compensation The fire and explosion index of the unit calculated previously refers to the inherent danger of the materials and processes in the unit, without considering any actual safety measures. According to the value principles of the "Dow" compensation coefficient and the actual situation, calculations were made from the three aspects of process control, material isolation and fire prevention measures. The results are shown in Table 5. Table 5 Calculation table of fire and explosion hazard index after compensation Editor’s note: Due to limited space, only the results are retained in the above table, and the intermediate processes are deleted. 　　3.4 Evaluation results (1) The largest material coefficients MF are aromatic hydrocarbons and air mixture (oxidation tail gas) and concentrated hydrogen peroxide, both of which are 29 ； Secondly, the mixture liquid of aromatics and alkenes H2O2 and hydrogen are 24 and 21 respectively. ； The smallest ones are aromatic hydrocarbons and mixtures of aromatic hydrocarbons with a small amount of H2O2, both of which are 14. This shows that the substances in the oxidation, concentration and packaging units themselves are very dangerous and should be given full attention. 　　(2) Among the 7 units evaluated, the fire and explosion indexes of hydrogenation, oxidation, and concentration are 134.0, 232.0, and 170.2 respectively. It can be seen that the inherent risks of these three units are quite high. When safety measures are taken into account and compensation is given, the inherent hazard index can be reduced by 38% to 61%. 　　(3) When safety measures are taken into consideration, compensation should be given by 9% to 44%. 　　4 Labor safety and health countermeasures From the previous analysis, it can be seen that the main dangerous and harmful factors existing in the hydrogen peroxide production process are:: Fire, explosion hazard, toxicity hazard, etc. ； Therefore, during the construction process, relevant specifications and standards must be strictly observed. Any behavior that ignores or lowers standards will leave hidden dangers of accidents and jeopardize safe operation in the future. The countermeasures proposed here are also mainly aimed at these major hazards and hazards. Countermeasures against other hazards and hazards are limited in space and will not be discussed. 　　4.1 Anti-virus countermeasures There are toxic media in the production process of this device: Anthraquinone, heavy aromatic hydrocarbons, phosphoric acid, hydrogen peroxide, etc. are key targets for prevention. 　　4.1.1 Selection of process parameters Although the hydrogen peroxide device does not have high temperature and high pressure requirements, many process controls require high operating accuracy and frequency. Attention should be paid to the selection of process parameters and quantity control, and to explore the best operating conditions. Such as stopping hydrogen and replacing nitrogen when the hydrogenation process is stopped, acidity control in the oxidation process, raffinate content control, drying tower alkalinity control, H2O2 stability control in the deep shrinkage process, etc. 　　4.1.2 Equipment material selection. Based on the strong oxidizing properties and easy decomposition of hydrogen peroxide, the equipment material in contact with the working fluid or raw materials in the hydrogen peroxide device is selected from 0Cr18Ni10Ti. Stainless steel added with Ti can improve the resistance to intergranular corrosion. The equipment should be polished, cleaned, and pickled and passivated before use. ； Through practical experience and device design knowledge from other devices and similar projects, the equipment should be able to ensure complete airtightness ； Specific measures should include: Key pipelines with higher vessel design margin, higher pipeline design level and higher pressure level, etc. 　　4.1.3 Alarm and safety interlock For special work sections and positions, toxic gas monitors must be installed at the discharge port, sampling port, storage tank valve, transfer pump and compressor when toxic materials are in abnormal operation. ； Corresponding toxic gas monitors should be installed within 30m of the control room, power distribution room and equipment containing toxic materials. 　　4.1.4 Where the isolation body is equipped with operating positions, such as control rooms, power distribution rooms, operating rooms, laboratories and other buildings, a positive pressure ventilation system should be installed and can withstand a certain external pressure. There should be activated carbon adsorbers at the air inlets. ； Heavy aromatic hydrocarbon storage tank areas should be equipped with protective lifts. 　　4.1.5 Strengthen personal protection. Emergency showers and eyewash facilities should be provided in all areas where the human body may be exposed to harmful substances that may cause burns, irritation or damage to the skin. ； In addition to general protection such as protective glasses, gloves, and eyewash showers, special gas masks should also be provided ； The use of personal protective equipment, such as air breathing masks, full-body PVC protective clothing, gloves and protective goggles, etc., should be mandatory for critical operations. 　　4.1.6 Strengthening safety management In addition to the above targeted measures, attention should also be paid to strengthening safety management during the production process, such as conducting comprehensive and systematic safety maintenance training for employees, establishing and improving safety management systems, and regular safety inspections. 　　4.2 Fire prevention countermeasures 4.2.1 Strict compliance with standards During design and construction, safety fire protection measures should be set up in strict accordance with relevant specifications and standards. Equipment handling flammable and explosive hazardous materials should have pressure relief facilities, including safety valves, release valves, pressure control valves, etc. ； Design gas monitoring, alarm and interlocking systems for workplaces where hydrogen, heavy aromatic hydrocarbons and hydrogen peroxide may escape ； When designing a centralized positive pressure ventilation control room, it is necessary to ensure that the ventilation air is not polluted, and the air inlet is designed with a filter using activated carbon or other adsorbents as the filter medium. 　　4.2.2 Distributed Control System (DCS) The engineering design adopts a reliable distributed control system (DCS) to realize the normal operation of the production process, start and stop operations, and centralized control of production process data collection, information processing and production management. It also designs automatic adjustment of important parameters and over-limit alarm and interlocking systems to ensure the safety of production equipment and people. 　　4.2.3 Electrical explosion-proof engineering design Electrical circuits in explosion- and fire-hazardous locations should be laid in accordance with relevant regulations and specifications. Explosion-proof lighting equipment should be used in explosion- and fire-hazardous locations. 　　4.2.4 Firefighting facilities Considering the fire risk of this project, it is recommended that the fire pump should be able to start automatically and continuously, and can also be started remotely from the control room to quickly start the fire water system in the event of an accident. ； It is recommended to add a diesel generator set for the exclusive use of fire-fighting water in case of failure of the normal power supply dual circuit. 　　5 Conclusion Through the previous analysis, the following conclusions can be drawn: 　　(1) The main occupational hazards and harmful factors of hydrogen peroxide devices are fire, explosion and poison hazards, and measures should be taken to prevent and control them. 　　(2) Noise, falling from height, electric shock, mechanical injury and other dangerous and harmful factors are not outstanding occupational hazards, but corresponding measures should be taken to protect them. 　　(3) According to the analysis of the operation status of domestic in-service devices, it is shown that by implementing various labor safety and health countermeasures, hydrogen peroxide production devices can basically achieve the purpose of safe production. However, due to the particularity of hydrogen peroxide production, harmful factors such as toxic and harmful gases and noise may still exceed * * According to the provisions of health standards, advanced safety measures at home and abroad should be adopted for comprehensive management. 　　(4) Safety countermeasures should be fully implemented and should be designed, constructed and put into use at the same time as the main equipment, and safety management should be strengthened.

Come in and learn in a low-key manner* ,Thanks to the landlord and the enthusiastic people on the floor.

Reply 11# jhff Hello, please tell me how to calculate the material balance and heat balance of the anthraquinone hydrogen peroxide device, thank you.

study* study * , I don’t know anyone who has relevant information on the production capacity of more than 100,000 tons. I only have personal knowledge. * bao13999700601@163.com