The prices of low-voltage variable frequency drives (VFDs) have declined substantially since they were introduced, while the cost of power has increased. Normal project economics will now justify these VFDs — which go up to 375 kW (500 hp) or…
For most solids-processing operations in the chemical process industries (CPI), particle-size reduction and screening (classification) to achieve the desired particle-size are required, since processes rarely produce the desired size directly. When designing processes, selecting equipment and looking for ways to…
Many CPI applications require the injection of chemicals, such as corrosion inhibitors, precipitation inhibitors, oxygen scavengers and countless others, into the process during operation. Follow these tips to design and operate a system that ensures accurate delivery of performance chemicals,…
This article covers permitting and directly related design issues associated with thermal processes used for drying and calcining, using the production of ceramic proppants as an illustrative example. While the magnitude of permitting issues varies significantly with air-quality attainment area…
Inorganic acids play a major role in the chemical process industries (CPI). They are used as raw materials, catalysts or finishing and pH control agents in the manufacture of a wide range of chemical products, from fertilizers to detergents, and…
Small chemical reactors offer a number of benefits compared to large reactors, such as better heat transfer and mixing. While small batch vessels are impractical at the industrial scale, continuous flow reactors can provide the benefits of small physical size…
Blending and segregation are two opposite and competing processes in solids handling that ideally fit the expression “two sides of the same coin.” But, if you think about it, coins have three sides and sampling completes the idiomatic expression perfectly.…
Vacuum conditions for many unit operations — including distillation, evaporation, drying, crystallization, filtration and more — are typically achieved using the following three approaches: • Steam ejector systems • Mechanical vacuum pumps • Integrated vacuum systems (which combine steam ejectors…
Fans and blowers are common in air-handling and movement systems used in the chemical process industries (CPI). Two major uses of fans and blowers are in pneumatic conveying systems and in ventilation and air-pollution-control systems. Powering fans and blowers can…
Pumps are among the most commonly used machines in the chemical process industries (CPI). Condition monitoring tests and predictive maintenance can help pump operators determine when to overhaul pumps in a way that minimizes costs. Despite pumps’ ubiquity and large…