By Marco Lendi, Dr. Heinz Wagner, Dr. Peter Wuhrmann, and Randy Turner, Swan Analytical
Proper measurement of pH is a key factor of corrosion risk surveillance in water-steam cycles. Since it still seems to be difficult to measure the sample pH directly with glass electrodes, pH calculation, using the difference of sample conductivity before and after a strong acid ion exchanger, is a frequently used alternative.
Both sodium and calcium sorbents have been used as dry sorbents for the mitigation of acid gas for the past 30 years with great success. “Calcium (lime-based) sorbents vs. sodium (sorbents)” itemizes the fundamental differences, pros and cons between them, and the properties that make sodium bicarbonate and trona well-suited for air pollution control.
Smart electro-pneumatic positioners form the vital link between the control system and the valve. Electro-pneumatic positioners from ABB incorporates auto-adjust to reduce commissioning time and an adaption program provides for optimal control of the position until set point is reached.