Choosing the appropriate monitoring instrument for liquid ammonia storage is the premise to ensure safe production. The main instruments in liquid ammonia tank farm include liquid level, temperature, pressure, toxic (combustible) gas alarm, etc. For the tank farm where the system transformation and wiring are difficult, the solution of wireless instrument can be adopted.
Liquid ammonia is a highly dangerous chemical substance, and the accurate use of liquid level gauge is the main safety accessory to ensure the safe operation of storage tanks. Most liquid ammonia storage tanks are designed with floating balls. The advantages of this level gauge are accurate indication and small error, but the disadvantage is that it is easy to get stuck, which leads to the failure of the level gauge. Do not have the function of remote transmission. The liquid ammonia tank is safe, and the principle of minimum opening is adopted to ensure the best overall strength of the tank. In order to ensure that the liquid level can be monitored safely and the original liquid ammonia storage tank will not be penetrated, it is suggested that users choose the ELL external liquid level meter invented by Dinghua Electronics to monitor the liquid level in this part of the tank farm. The liquid level gauge is different from the ordinary liquid level gauge, and there is no need to open holes in the tank. The magnetic probe is attached to the outside of the metal tank wall, which can monitor the real-time liquid level of the tank through the principle of vibration analysis, which is safe and reliable and never touches the medium.
Due to the characteristics of liquid ammonia, it is suggested that the storage capacity of liquid ammonia should not exceed 85% of the capacity. As the liquid level measurement of the storage tank, the liquid level gauge can monitor the change of the liquid level in real time and set the upper and lower alarm points according to the field process conditions. When the liquid level reaches or exceeds the alarm limit, the operator should be informed to deal with it in time to avoid potential danger.
For some customers who only need high liquid level alarm when measuring liquid ammonia tank, it is suggested to use an external liquid level switch with the same principle as the external liquid level meter for external measurement, so that the liquid level and set value in the tank can be monitored in real time without opening a hole. Once it reaches or exceeds, the switch signal 1 will be immediately output to the controller or alarm, which is convenient for the staff to do the corresponding preventive work.
Use explosion-proof and corrosion-proof pressure and temperature instruments to detect and record the state of liquid ammonia in real time. The temperature and pressure of the original storage tank can be transformed into a pressure and temperature transmitter with remote transmission function and local display. For some users who have no additional holes in the tank, it is suggested that users can use the external temperature sensor of Dinghua Company to measure the tank wall temperature at close range, so as to know the temperature of the medium in the tank.
Components such as gas phase inlet and outlet, liquid phase inlet and outlet, sewage outlet, discharge outlet, instrument interface, safety valve interface and pressure gauge interface of liquid ammonia storage tank, such as connecting pipes, valves, flange connections and seals, may fail or leak. Reasonable arrangement of toxic (combustible) gas probes in the leakage area of the tank farm, and recording the concentration of toxic (combustible) gas in the air around the tank farm. Once the standard is exceeded, this signal will be sent to the alarm immediately.