8 Essential Safety Devices for Chemical Industry Workers: What You Need to Know

Thread Content

Due to the hazardous nature of chemical production, many safety devices are installed during the design and construction of chemical plants. These safety devices serve as life-saving tools for us chemical industry workers at critical moments. Let’s take a look at some of these safety devices together. 1. Bypass pipes (valves): In automated chemical processing systems, bypass channels are provided on both the feed and discharge pipes. The main purposes of installing bypass pipes are, first, to meet the requirements of centralized control operations, and second, to fulfill safety requirements to the greatest extent possible ； Third, it meets the needs of continuous production of the device. http://p4.itc.cn/images01/20201111/d24524b000154b309f6396ac1a8b97fc.png The bypass pipe is usually installed above the automatic control valve; during operation, when the instrument-based automatic control valve is functioning properly, it remains in a closed state. When the automatic control valve fails or is under maintenance, closing the maintenance valves on both sides and opening the bypass valve allows for continuous production. When equipment failure leads to a loss of control, it is also possible to use bypass valves to redirect the flow and control the situation, thereby reducing the risk. To determine whether the bypass valve is open or closed, one needs to check the length of the valve stem screw: if the screw is long, the valve is open; if it is short, the valve is closed. The valve is opened counterclockwise and closed clockwise. The shape speed must be determined based on factors such as pipe diameter and flow velocity; generally, the larger the pipe diameter and the higher the flow velocity, the slower the switching speed, in order to prevent sudden high pressures. To completely cut off the flow, both the main valve and the bypass valve must be closed simultaneously. 2. Emergency shut-off valve: The emergency shut-off valve is an important safety device in automated production systems. In cases of production abnormalities or accidents, the control room of the system can remotely control to directly shut off the feed valve. Emergency shut-off valves are generally installed on the feed pipes of more hazardous devices, with maintenance valves on either side of them. 3. Safety valves, vent pipes, recovery pipes, and flares are important safety components in pressure devices; when the pressure inside the reactor or device exceeds a certain level, the safety valves will open automatically to release pressure or vent it. To ensure safety for the vented material, a recovery pipe is installed on the vent valve, allowing the vented material to be recovered and stored in the material tank, or to be vented to a flare for combustion. However, some enterprises with relatively backward production technologies or poor production conditions do not install recovery pipes and simply vent the gas in case of an accident. The release of materials (sprayed material) without recycling can lead to combustion explosions or the escalation of accidents. Flame arresters should be installed on the pipelines for direct air defense. The operating pressure of the safety valve is adjusted according to the requirements of the device. 4. Explosion-proof membrane (burst disc): A thin metal sheet installed on the pressure relief hole of a pressure device is called an explosion-proof membrane, also known as a burst disc. When the device pressure exceeds a certain value, the metal sheet ruptures, thereby achieving the purpose of a pressure relief protection device. http://p5.itc.cn/images01/20201111/f85807830b9647ff8f14fd607e6e8be7.png Since the fireproof membrane bursts, a large amount of material is ejected, posing an even greater risk to the equipment. Therefore, a vent and recovery pipe is generally installed on the explosion-proof membrane to recover the materials ejected after the explosion of the membrane into a tank or to vent them for combustion in a flare. However, some units with poor production conditions do not have vent recovery pipes installed. Some devices are equipped with double layers of explosion-proof membranes, and data acquisition devices are installed between these membranes to enhance the safety of the reaction. 5. To control process parameters, improve the quality and efficiency of chemical production, and ensure production safety, data collection devices are installed in various parts of manufacturing equipment to monitor parameters such as temperature, pressure, and the status of materials (products). These devices provide operators with accurate real-time data. A failure of these data collection devices can pose a serious threat to production safety. 6. Nitrogen and steam purging systems: Most chemical processing units are equipped with nitrogen and steam purging systems. The piping networks of these systems are closely connected to the units, and when required by the production process, the nitrogen or steam systems can be activated automatically or manually to support the production process. During equipment emergency repairs, the device can be purged and replaced to ensure safety during these repairs ； When the device malfunctions or an accident occurs, it can be used to purge the pipelines, accelerate vaporization, increase flow rates, and prevent material deposition and blockages. It can also dilute the material, reduce its concentration, slow down reactions, or provide pressure protection for the material. Additionally, it can serve as a diluent and fire extinguishing agent for dealing with leaks and fires. 7. Alarms in the control room are triggered when there are abnormalities in process parameters such as temperature, pressure, and flow rate of alarm devices and fire suppression systems. The detectors and alarms for combustible gas and toxic gas concentrations installed in the production facilities and their vicinity are all important safety devices in chemical production. http://p0.itc.cn/images01/20201111/5be2e2283c104148bd91458a1ca813ed.png To ensure rapid and effective response in the event of an accident at a facility, many chemical processing units are equipped with water spray systems, foam spray systems, high-pressure fire hydrant systems, as well as fixed fire cannon cooling and extinguishing systems. These fire suppression facilities play a crucial role in controlling the development of situations under certain conditions. 8. Pipeline identification: Chemical production pipelines are crisscrossing and highly complex. To facilitate management, standard identification systems for these pipelines have been established in the industry; this not only helps production workers carry out their tasks more easily but also aids in firefighting and rescue operations. Normally, pipelines for materials that are prone to corrosion are made of stainless steel and are not painted ； The circulating water pipeline is painted ink green ； Powder coating on acid (alkali) liquid pipelines by color ； The nitrogen purge pipeline is painted light yellow ； The vent pipeline (emergency discharge pipeline) is painted yellow ； Fire water supply and extinguishing agent delivery pipelines are painted red ； The steam pipeline is fitted with insulation covered by galvanized iron sheeting ； The main material pipeline is not painted. Does your chemical company have safety devices for chemical production? For the safety of your employees and the protection of your company’s property, it is essential to have these safety devices in place to prevent accidents. This article is reprinted from China Hazardous Chemicals Logistics Network.