The use of a single chemical or refinery process unit alternately in more than one operation; for example, a catalytic reactor will first produce a chemical product and then will be blocked from the main process stream during catalyst regeneration.



Related Terms

BATCH

  1. The quantity of material required for or produced by one operation. 2. An amount of material subjected to some unit chemical process or physical mixing process to make the final product substantially uniform.

BLOWDOWN STACK

A vertical stack or chimney into which the contents of a chemical or petroleum process unit are emptied in case of an operational emergency.

BY-PRODUCT

A product from a manufacturing process that is not considered the principal material.

BUTANE VAPOR-PHASE ISOMERIZATION

A process to isomerize normal butane into isobutane in the presence of aluminum chloride catalyst and hydrogen chloride promoter.

TITRATION

A chemical process used in analyzing feedwater.

ACID PROCESS

A chemical pulping process that uses an acidic calcium sulphite solution plus heat to break the bonds in wood between the cellulose and the wood fibres.

INHERENT VICE

An insurance term referring to any defect or other characteristic of a product that could result in damage to the product without external cause (for example, instability in a chemical that could cause it to explode spontaneously). Insurance policies may exclude inherent vice losses.

COUNTING CIRCUIT. COUNTERCURRENT EXTRACTION

A liquid-liquid extraction process in which the solvent and the process stream in contact with each other flow in opposite directions. Also known as countercurrent separation.

ASSEMBLY LINE

A mass-production arrangement whereby the work in process is progressively transferred from one operation to the next until the product is assembled.

BATTERY LIMITS

An area in a refinery or chemical plant encompassing a processing unit or battery of units along with their related utilities and services.

Related questions

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