Steam is a critical part of many process manufacturing processes and the energy to produce it can be a significant source of operational costs. Jim Cahill recently caught up with process automation hall-of-fame member Greg McMillan and Emerson’s Scott Pettigrew at the Emerson Exchange conference in Austin.
Greg and Stan Weiner had recently interviewed Scott in a ControlGlobal.com article, Boilers as fast as can be.
To highlight just a sampling of their wisdom shared with the readers; read the entire article. Greg opened noting:
Steam header pressure controllers can be properly tuned for fast response, and use feedforward signals and half decouplers to minimize disruptions in a header and between headers from large changes in steam usage and generation by production units.
He asked Scott about ways to minimise purchased fuel usage on multi-fuel boilers. Scott explained:
We can use boilers running on waste fuel to take all the swings in the plant steam demand within minutes. The starting point is good flow measurements and computations on a mass flow basis.
Coriolis flowmeters are great in terms of providing the most accurate mass flow measurement with the greatest rangeability, as well as density measurement with incredible precision. However, for solid fuels, very large lines or other applications where Coriolis flowmeters are not practical, strategies can provide the missing information as long as the flow measurements are relatively repeatable.
