Patent ID: 8863538

Claim:
A method of purifying ammonia from contaminated refrigeration fluid in an ammonia refrigeration system, the method comprising the steps of: (a) allowing contaminated refrigeration fluid from the refrigeration system to flow into a tank; (b) heating the contaminated refrigeration fluid in the tank with a heat exchanger and preventing further contaminated refrigeration fluid from flowing into the tank during the heating step; (c) measuring the contaminated refrigeration fluid level in the tank; (d) separating anhydrous ammonia from the contaminated refrigeration fluid; (e) removing the separated anhydrous ammonia; (f) returning the removed anhydrous ammonia from the tank to the ammonia refrigeration system; (g) measuring an upper temperature of the contaminated refrigeration fluid between the tank and the heat exchanger; (h) measuring a lower temperature of the waste fluid after leaving the heat exchanger; (i) measuring a tank fluid level in the tank; (j) discharging waste fluid from the heat exchanger once the upper temperature and the lower temperature are equal and the tank fluid level reaches a set maximum tank fluid level; and (k) preventing contaminated refrigeration fluid from flowing into the tank and anhydrous ammonia from leaving the tank during the discharge of waste fluid.