This is a combination pure steam generator and WFI distillation plant used for manufacture of pharmaceutical grade water and pure steam. The system was attained second source and commissioned after approximately 10 years of being in storage. New integrations and re-design of the tank system posed challenges for start-up and operation, especially under tight project timelines, but with the right resources, the system has been producing USP grade WFI and compendial pure steam since implementation.
Water For Injection distillate for the unit averages around 0.01 microsiemens. Effects of plant steam quality and choice of boiler controls can influence operations, making manual intervention required to keep adequate flow to the column. We are studying the effect of different pressure reducing valve configurations to minimize the fluctuations in plant steam pressure, thus lessening the need for system PID controllers to work harder to modulate valve positions and achieve a steady pure steam pressure.
Here’s an update on the system:
ReplyDeleteWe changed out the pressure reducing valve due to a plant steam leak in the pilot portion of the valve where the mushroom head seats onto the valve body. According to the valve manufacturer, which is based off an old Bailey G-4 design, “the mechanism’s pilot operated pressure reducing valves provide extremely accurate levels of pressure regulation for steam”. We did not see this with a new replacement. The plant steam boiler fluctuations still occur with a 20 PSI span between high and low readings. Sometimes plant steam will fluctuate to an even lower pressure, causing the still to alarm on a low pressure event. We have seen less bouncing of pressure on plant steam pulses, and so our PSI readings are not so erratic given a steady supply of plant steam and a steady demand on the boiler (The unit requires about 130 lbs/hr plant steam). We may consider installing a balance pipe and monitoring the difference in pressures, but that requires modification of the generator skid since it is a very tight fit.
The WFI generator is still pumping out compendial water and producing pure steam for our plant operation, and conductivity is typically around 0.01 microsiemens. A very good unit for making water, the 300PFS-C is a true workhorse. We are able to produce on a good day roughly 300 liters and hour.