This paper describes a Direct Fired Liquid Nitrogen Vaporizer Automation System (LN2 Vaporizer Automation) and the control equipment and techniques associated therein. This system has been developed over the last two years and has proven capable of controlling the discharge temperature of discharged nitrogen gas, across a broad range of rates and pressures in a wide range of ambient conditions, while controlling pollutants from the burner and providing for enhanced safety and reliability.
The key components of the system are:
a. Typical Direct Fired Liquid Nitrogen (LN2) Vaporizer System
b. A Program Logic Controller (PLC) with attached sensors and actuators
c. A Human Machine Interface (HMI) to allow for interaction with the system
The trials and jobs carried out to date are also briefly described in this paper, together with the current perceived strengths and weaknesses of the system.