Specialized system automates a continuous process industry plant.
by Balvinder Rai, Tajna River Industries

Tajna River Industries is a continuous process chemical industry that manufactures bleached lac, shellac flakes, shellac wax and seedlac. In addition to production floors, the plant also has a water treatment plant, chiller units, a steam producer, a sodium hypochlorite preparation plant, a gasifier (wood to producer gas) and diesel generator (DG) sets.

To improve its system by reducing inputs, manpower, power consumption and downtime, Tajna River Industries decided to automate and control the manufacturing unit with a custom system. The chosen system was National Instruments’ LabVIEW software that created an automation and control system that met the plant’s application needs. This article summarizes the improvements provided by the new software.


Speed Control of Diesel Generator Sets

The DG sets are powered by a mixture of diesel and producer gas created in an 80-kilowatt gasifier. The engine speed increases as more gas is input, so the diesel fuel intake must be reduced to achieve constant engine speed and line frequency. The engine speed is detected by using the software to find the frequency of the tone generator output attached to the engine shaft. The closed-loop control system generates signals through the multifunction software system’s data acquisition (DAQ) device to control diesel flow in the engine. The output from the DAQ device is applied to a small DC motor through a DC regulator IC that screws or unscrews the generator’s fuel control screw.