Like many other facilities and industries, a pulp & paper mill is billed by the local wastewater district based on the amount of the plant’s discharge. This particular mill’s effluent meter, an open channel Parshall flume - a type of venturi flume, was consistently measuring lower than the district’s magnetic flow meter, or magmeter. The disagreement led the mill to hire an independent consultant engineering firm to investigate the discrepancy. To the mill’s displeasure, the consultant agreed with the district that the magmeter was reading correctly and that the Parshall flume was reading low.
With the mill still not convinced, Controlotron’s local representative was engaged to provide meter verification services on the Parshall flume. Once again, the Parshall flume was found to be reading low and, once again, the magmeter was proven to be consistent with outside verification. Due to the experience and knowledge of the representative and the unique aeration detection capability of the company’s transit-time flow meter, however, an investigation of the effluent quality indicated that significant foaming was taking place. This foaming created errors in both the Parshall flume as well as the district’s magnetic flow meter.
As a result of the representative’s investigation, a Controlotron System 1010N transit-time flow meter was installed with the meter’s flow rate and aeration outputs connected to an anti-foam control system. This system inhibited the creation of foam, and reduced the actual discharge measured by the district’s meter. Additionally, the mill’s new flow meter and the district’s meter were in agreement. Based on the reduction of actual discharge from 20 mgd to 14 mgd, the mill recognized a savings of $83,000 per month., providing a return on investment of two weeks for the new anti-foam control system and flow meter.
This example illustrates how this transit-time flow meter - with its unique diagnostic abilities - can do more than just measure flow. IWW
Contact: Controlotron Corp., of Hauppage, NY, 631-231-3600, [email protected] or www.controlotron.com.
