SOLID LIQUID SEPARATIONS IN PILOT AND （在飞行员和固液分离）.pdfVIP

SOLID–LIQUID SEPARATIONS IN PILOT- AND COMMERCIAL- SCALE OPERATIONS 1 2 Dennis Gertenbach , and Brian L. Cooper Paper 428c, for presentation at the AIChE National Meeting, November 10, 2010, Salt Lake City, UT ABSTRACT Benchtop processes that are developed with the intent of being run at the demonstration scale present a multitude of technical challenges. Solid-liquid separations are among the most common process operations that become large and often unanticipated capital and operational costs due to insufficient development effort in the research phase. Often separation technologies from established industries can be applied to new processes to mitigate the risk involved with scale up. The presentation will focus on Hazen’s experience with solid-liquid separations, including dissolved air flotation (DAF), counter current decantation (CCD), as well as various incarnations of filtration and centrifugation. SOLID-LIQUID SEPARATIONS Separation costs are difficult to isolate given the complexity of the chemical industry but have been estimated to account for between 40 and 70% of capital and operating costs in a commercial process.3 The principles and technologies are well-established and criteria for equipment selection are available, yet these unit operations continue to present difficulties in scale up and operations. Separation processes are often not given sufficient attention at the pilot scale; it is more common to adopt a trial-and-error method in development until a piece of equipment that offers promise is selected at the bench scale. Very often, a small variance in the process can render the specified equipment useless and cause a return to the design phase or worse, development at scale. All mechanical separation equipment, with the possible exception of those used for impingement, are based on the principles of sedimentation or filtration,4 as shown in