Technical & Practical
Making Pump Maintenance Mandatory
One of the key components in the operational success of chemical process industries (CPI) facilities is the transfer pump. These pumps must handle a wide variety of materials under a broad range of operating conditions. These diverse operational conditions may…
Characterizing Powder Flow
To confidently design, operate and troubleshoot solids-handling processes, engineers need to characterize powder flow in ways that relate to in-plant behavior. Universal powder testers provide the multi-faceted characterization that is necessary to reliably predict operational performance. This article examines the…
Believe your instruments, unless…
I was having a “wallflower moment” after Ms. Ruth Sands’ excellent troubleshooting presentation at the March AIChE meeting. That presentation was well summarized by Editor in Chief, Rebekkah Marshall in the April issue of CE (p. 5). I wanted to…
Specifying Elastomer Seals for Plastic Piping
The chemical process industries (CPI), like many others, increasingly employ non-metallic piping systems for fluid transfer — including polyvinyl chloride (PVC), chlorinated polyvinyl chloride (CPVC) and fiberglass-reinforced plastic (FRP) — instead of exotic metal piping. While non-metallic piping systems have…
Moving Air In Pneumatic Conveying Systems
Dilute-phase conveying systems generally use centrifugal fans and positive displacement blowers for supplying conveying air to the conveying system. However, for some conveying systems, compressed air from a central compressor station is also used. The two important criteria required for…
Reboiler Condensate Drums: Silencing Hydraulic Hammer
Condensate pots are commonly used on the condensing sides of some reboilers, such as those that are heated by steam or refrigerant vapor. These pots provide a liquid seal that prevents uncondensed vapor from blowing out of the reboiler into…
Reduce Costs with ‘Step-down’ Filtration
Among the challenges of effective solid-liquid filtration is the accumulation of solids on the filter surface, which creates an increasingly dense mass that process fluid must push through. In many applications in the chemical process industries (CPI), a step-down filtration…
Tank Vapors: Optimize Ejector Sizing for Better Control
Properly sized ejector stations can save capital costs and reduce downtime Steam-assisted, gravity-drainage (SAGD) operations employ large tanks that vent flammable and sometimes toxic gases. Safety and environmental concerns often require engineers to design vapor-recovery units (VRUs) to collect these…
Calculate Liquid Volumes in Tanks with Dished Heads
This article presents equations that allow the user to calculate liquid volume as a function of liquid depth, in both vertically and horizontally oriented tanks with dished heads. The equations accommodate all tank heads that can be described by two…
Sterilization Approaches
Maintaining high-purity conditions in the chemical process industries (CPI) depends in large part on the techniques used for sterilization. As a method to inactivate or eliminate potentially harmful microbes, sterilization can be achieved through a number of different approaches, such…