Cold Link Africa June 2019 | Page 15

PROJECT INCORPORATING COLD CHAIN Train transporting bananas from agent area to ripening rooms. room temperature value is fed into the proportional-integral-derivative (PID) algorithms to regulate the temperature to control precisely within a 0.2°C band of the set point. Once the produce is on temperature, the ripening cycle begins and the ethylene gas is introduced and regulated using Pulse Width Modulation (PWM) duty control through PID (to prevent overmixing the air with too much ethylene). Up to four ripening profiles can be selected and completely configured by the end user depending on the grade of produce and time required to ripen the bananas. Once the ripening cycle is complete, the room can automatically change state into a regular cold room with defrost functionality, etc. if the end user chooses to do so. Once the room is emptied and switched off, the cycle is reset and the room can be reloaded. Pump station foreground, Aermec chiller background. Loni Nicolopulos (left) and Kevin Walter of Lutz Refrigeration. Ethylene gas bottles (5% ethylene, 95% nitrogen). Product spike to measure banana core temperature. COLD LINK AFRICA • June 2019 www.coldlinkafrica.co.za 15