PERCHLOROETHYLENE SYSTEMS: STANDARDS AND EMISSIONS
Firbimatic Metal Cleaning Division hermetically sealed solvent systems demonstrate extremely low solvent consumption levels. Such low consumption is achieved by efficient vacuum drying and effective separation of solvent and contaminants by fractional distillation.
Depending upon the levels of contamination introduced into the system the waste stream may contain very low levels of solvent. The option of additional by-pass distillation remains available to further concentrate the contaminants. In fact a small amount of solvent in the waste stream is beneficial in order to maintain fluidity and avoid the build up of a viscous sludge. The object is to maintain a closed loop operation where the operator has no contact with the solvent or waste stream.
VOC STANDARDS IN PERCHLOROETHYLENE SYSTEMS
Important international standards regulate and limit the maximum levels of both fugitive emissions (into the workplace) and atmospheric discharges. In the case of perchloroethylene, the consumption limit adopted is 100 g/h.
More specifically, EU directive 1999/13/EC (“The Solvent Emissions Directive”) and the UK’s domestic legislation The Solvent Emissions (England and Wales) Regulations 2004 indicates a maximum limit of 20 mg/m3 in the event of consumption exceeding an excess mass flow of 100 g/h.
Firbimatic perchloroethylene systems operate well within the mass flow limits rendering them “compliant at source” . Carbon abatement is adopted purely as the final “policeman” in order to guarantee long term compliance.
In addition to this, EuroNorm 12921/4 requires that residual chamber concentration is reduced to <1gm/m3 prior to the door mechanism permitting operator access to the chamber.