Most control systems use Proportional-Integral-Derivative (PID) algorithms for controlling DO, basin air flow distribution, and blower pressure or flow. These algorithms are prone to hunting - the cyclic fluctuation of the controlled variable. Fluctuations that oscillate the DO several mg/L above and below the target DO concentration are common.
By using state-of-the-art vacuum technology for degassing mineral water, it has been possible to save an average of 3,000 cubic meters of water per filling plant per year. The solution was to replace the existing liquid ring vacuum pumps with MINK claw vacuum pumps from Busch Vacuum Solutions.
An envelope manufacturer is upgrading their vacuum system to include a new VSD controlled pump. As part of the preparation for the installation, an energy baseline was developed, and leakage survey conducted. The auditor used a newly developed acoustic imaging camera as well as a basic ultrasonic leak detector gun. This article describes what was found and some of the challenges faced in detecting leaks in a busy plant.
This article aims to discuss the various technologies of equipment that could be presented to a wastewater operator faced with a temporary need for blower air and to help the operator understand the impact (both monetarily through a “Total Cost of Rental” approach and environmentally) of their decisions.