Liquid ammonia safety monitoring plan

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This post was last edited by yuchenchf on 2016-6-14 at 16:58. System overview: Given the hazards associated with the liquid ammonia storage area, proper selection of instruments, real-time monitoring and early warning systems, correct processing procedures, and accident prevention plans are essential for ensuring safety control. To address the risks of poisoning, fires, and even explosions that may arise from the storage and leakage of liquid ammonia, it is necessary to take measures to prevent such leaks and to know how to deal with them once they occur. Selecting appropriate monitoring instruments for liquid ammonia storage is a prerequisite for ensuring safe production. The main instruments in the liquid ammonia tank area include level, temperature, pressure, and toxic (flammable) gas alarms. For tank areas that have undergone system upgrades and where wiring is difficult, wireless instrument solutions can be used. Liquid ammonia is a highly dangerous chemical substance. An accurate and reliable level gauge is a crucial safety device to ensure the safe operation of storage tanks. Most level gauges used in liquid ammonia storage tanks are of the float-type; their advantage is accurate indication with low error, while their disadvantage is that they can get stuck, leading to malfunction. It also does not have remote transmission capabilities. For safety reasons, the liquid ammonia tank follows the principle of minimizing openings to ensure optimal overall strength of the tank. To ensure safe monitoring of the liquid level without having to make any openings in the existing ammonia storage tanks, it is recommended that users use ELL external level gauges for the level monitoring in this area of the tanks. Unlike ordinary level gauges, this type of gauge does not require any holes to be made in the tank; instead, a magnetically attached probe is used, which is mounted on the outside of the metal tank wall. By utilizing vibration analysis principles, it is possible to monitor the real-time liquid level inside the tank. It is safe and reliable, as it does not come into contact with the fluid. Due to the properties of liquid ammonia, it is recommended that its storage level not exceed 85% of the tank’s capacity. A level gauge is used to measure the liquid level in the tank, allowing for real-time monitoring of any changes. Upper and lower alarm limits are set based on the specific requirements of the process in question; when the liquid level reaches or exceeds these limits, operators are immediately notified so that they can take action to prevent potential hazards. For those liquid ammonia tanks where there is no strong need for real-time level readings, and only an alarm when the level is too high is required, it is recommended to use external level switches that operate on the same principle as external level gauges. These also involve external measurement; no drilling is necessary. They enable real-time monitoring of the liquid level in the tank compared to the set point, and once that level is reached or exceeded, they immediately send a digital signal to the controller or alarm, allowing staff to take appropriate preventive actions. Select explosion-proof and corrosion-resistant pressure and temperature instruments to monitor and record the status of liquid ammonia in real time. The temperature and pressure of the existing storage tank can be locally modified into pressure and temperature transmitters with remote transmission capabilities and local display functions. For those users whose tanks do not have additional openings, it is recommended that they use external temperature sensors placed in close contact with the tank wall to measure its temperature, thereby determining the temperature of the medium inside the tank. There is a possibility of failure or leakage in various parts of the liquid ammonia storage tank, such as the gas inlet and outlet, liquid inlet and outlet, waste discharge ports, vent ports, instrument connections, safety valve connections, pressure gauge connections, as well as the seals at valves and flanges. Toxic (flammable) gas sensors are strategically placed in areas of the tank farm where leaks are likely to occur, in order to monitor the concentration of toxic (flammable) gases in the air surrounding the tank farm. Once the limit is exceeded, this signal is immediately sent to trigger an alarm. System features: Designed for the monitoring of liquid ammonia, it has numerous advantages for the prevention and management of liquid chlorine storage areas: 1. The storage area management system adopts a three-layer structure, offering clear hierarchy and distinct control functions. 2. A powerful alarm function that enables on-site alarms, alarms displayed in the control room, alarms via mobile phone or text messages, as well as a robust alarm interlock function. The system continuously records the level, temperature, pressure, and concentration of toxic (flammable) gases in the liquid ammonia tank area; whenever these parameters exceed the set limits, an alarm is generated on the monitoring screen to alert the operators. When the concentration of toxic (flammable) gases exceeds the limit, an alarm is triggered first, indicating the location where the alarm has occurred as well as the excess concentration. If the concentration continues to rise, the automated sprinkler system can be activated in accordance with the pre-established procedures, thereby reducing the temperature of the storage tank as well as the concentration of flammable (toxic) gases. The fan system can be turned on to disperse the ammonia gas, the emergency exit doors can open automatically, emergency lighting can be activated, and alarm messages for evacuation can be broadcast over the public address system, all of which help to ensure the safety of the production staff. The alarm signal is transmitted to the local 119 fire station, enabling timely and rapid response in order to minimize losses to equipment and personnel. 3. The i-Tank tank farm management system meets all the requirements related to the production, safety, and management of tank farms. A simple interface, easy operation, secure permissions, straightforward procedures, as well as mechanisms that facilitate use by operators and prevent accidental actions. 4. The simulation displays of the site and processes provide everything needed, including alarms, reports, and trends. 5. Control methods such as fully automatic system operation, interlocked semi-automatic operation, master controller jog control, and on-site manual control can be adopted. 6. The system features powerful communication interface capabilities; it allows the software’s visuals to be published on the web in webpage format for easy real-time viewing, and it enables the system’s display to be output to a large screen for clear presentation. 7. It can establish a data connection with vehicles carrying liquid ammonia, thereby enhancing corporate management capabilities. Plan description: A certain beer group is a state-owned listed company in China. As an important subsidiary in the Northwest region, the group’s Xi’an branch used manual visual inspection and routine checks to monitor the operation of its liquid ammonia tanks. The project mainly includes: 1. Monitoring, control, and alarm functions for the level, temperature, and pressure of the 3 liquid ammonia tanks in the liquid ammonia refrigeration station. 2. Layout and installation of liquid ammonia gas detectors in liquid ammonia freezing stations, warehouses, and yeast rooms. 3. Level monitoring and interlocking for the cooling circulating water station. 4. CO2 concentration monitoring and alarm interlock. 5. Interlocked control of the alarm fans and sprinklers for liquid ammonia concentration in the freezing station.