engiflow

Adsorption

A ventilator routes the collected vapours from the emission source through one of the two beds filled with activated carbon (AC filter). The hydrocarbon components in the vapour are adsorbed on the large surface area of the carbon. The clear air is vented to the atmosphere.

Regeneration

Before the on-line filter reaches saturation, the flow of incoming vapours is redirected to the clean filter. The first filter is regenerated by means of vacuum created by a set of booster and vacuum pumps. This cycle is time driven is and takes about 11 minutes.

Absorption

During regeneration, the stream of highly concentrated hydrocarbons is directed to an absorber column. A counter flow of fresh absorbent liquid, typically gasoline, absorbs the hydrocarbon components from the vapour stream. The absorbent liquid and condensed hydrocarbon components are continuously recycled to the storage tank. The non-condensed hydrocarbons and clean air leave the top of the absorber column. They go back to the bed in adsorption mode, after which the process re-starts.

Control system

The CVA units are equipped with

• an advanced Programmable Logic Controller (PLC)

• a bus communication between I/O station and PLC

• a PC based user-friendly Human Machine Interface (HMI).

This condition monitoring system continuously keeps track of key process parameters and the operation of the unit.

The control system includes features such as event and alarm log settings and a record of long-term development. The system enables operational adjustments, accurate service diagnostics and remote supervision.