A second-stage channel temperature controller system for attaining and maintaining the temperature of the fluidised bed Gasifier was developed and installed. The input temperature at the Gasifier was around 300 °C and the desired temperature was from 700 to 800 °C. The system was installed at CSIR-CMERI, Durgapur, and the field trials would be done after completion of first stage heat treatment system for coal gasification chamber as shown in Fig. 1. Two-channel flow control systems for controlling airflow rate for the fluidised bed were also developed and installed. The flow range of the system was from 0 to 800 slpm (0 to 48 m3/h) and from 0 to 1000 slpm (0 to 60 m3/h) with a resolution of 3 m3/h. The system was tested against a rotameter. The installed system is shown in Fig. 2. For coal feeding, a DC drive control circuit for solid material control was developed and tested. The drive controls a motor up to 2A load capacity. The system was tested at CSIR-CMERI, Durgapur (Fig. 3).
Fig. 1: Circulating fluidised bed (coal gasifier)
Fig. 2: Flow control system for circulating fluidised bed (coal gasifier)
Fig. 3: DC Drive controller for circulating fluidised bed (coal gasifier)