Biotech Facility Increases Throughput On Fermentation Vessel With Electronic Remote Sensor Technology

By Emerson Process Management

A biotech facility located in the Midwest was experiencing reoccurring problems with a vessel used for enzyme fermentation. In particular, the vessel was producing inconsistent batches.

These issues stemmed from the inability to get a repeatable level measurement on the vessel. Measurement errors often exceeded 3-5% of span with frequent spiking. Additionally, time response was extremely slow and was suboptimal for level control. Engineers at the facility had chosen to use a pressure-based solution to measure the level in the vessel because of agitators in the tank that would turn the process over in 3-5 minutes. A differential pressure transmitter with a remote diaphragm seal was installed on the bottom of the vessel. Impulse piping with a pneumatic repeater went from the top of the vessel to the low-pressure side of the differential pressure transmitter. Ultimately, the use of the mechanical repeater on such a tall vessel was the cause of the 3-5% measurement errors.

The lack of a repeatable level measurement in the vessel continued to be a source of frustration. Because of this, engineers were unable to calculate the yield of the fermentor. Engineers also had to back-check and forward-check all measurements in the process, resulting in increased operations costs. The level measurement in the fermentor would never match with the rest of the checks. Because of this, achieving consistent batch quality and throughput was difficult to achieve.