The lack of real-time temperature monitoring mechanisms in rotary digesters were resulting in overheads and hampering product quality. The plant was also at constant risk of accidents as there was no means for identifying temperature buildup inside the digestors. The conventional temperature monitoring systems can’t be used in rotary digesters as they were wired and the digestor was in constant rotation. The need was to implement a real-time monitoring system considering all these aspects.

Our team performed an in-depth study of the field application and considered various technology solutions and decided on a wireless temperature monitoring system. The system was designed such that it could be placed inside the digestor and continuously monitor the temperature. The system would also be with the existing PLC system in place in the plant.

The development included the design and architecture of hardware and firmware along with the integration of the client’s PLC over Modbus protocol. Zigbee connectivity was used for wireless communication. The system would measure the temperature every 30 seconds and send to the client’s SCADA system.

• Marked improvement in the product quality as it was easy to control temperature variation due to real-time monitoring.
• Enhanced plant operator safety as the temperature could be controlled as required.
• The SCADA integration made it possible for the operator to monitor the critical temperature parameters from the control room itself.