Minimizing energy losses in control valves

The pulp and paper industry uses massive amounts of energy, but it could reduce its electricity consumption by about 2,000 MW worldwide by simply optimizing the pumping of process liquids. Wasted pumping power can be significantly reduced by sizing pumps and control valves more accurately, and by using new methods of pump and valve selection. Combining the improved control valve's installed flow characteristic with state-of-the-art sizing and simulation programs ensures minimal pressure drop across the control valve without loss of accurate and reliable control in all process conditions. If accurate process condition information is available at the planning stage, even more significant pumping energy savings can be achieved. Moreover, reduced pressure drop across the control valve reduces the likelihood of valve cavitation. This, in turn, reduces the need for noise attenuation, preventing cavitation erosion, and repairing damage. To make the most of the advantages gained by using highly developed control valve sizing and selection programs, closer cooperation between process licensees, process users, and valve manufacturers is also required.