What are VOC's (volatile organic compounds)?

VOC Definition (according to EU-VOC-guideline 1999/13/EG):

All organic compounds which show a vapour pressure at 20 ˚C of 0.01 kPa (=0.1 mbar) or more
Or
Show a related vapour pressure under the actual conditions of application, e.g. higher temperature.

The aim of the EU-VOC-guideline is to minimize the VOC Emissions, due to their toxicity and climate changing character. The control of VOC emissions is becoming increasingly important due to changes in VOC regulations to combat climate change.

Examples of VOC's:

MEK (Methylethylketone)

PM (Methoxypropanol)

BTX (Benzene, Toluene, Xylen)

PMA (MPA, Methoxypropylacetate)

DPM (Dipropylenglycolmonomethylether)

MDG (Methyldiglycol)

Our process for VOC emission control / waste gas purification:

Waste gas purification by Enviolet® UV Oxidation (Advanced Oxidation Process) It is a combined process of wet-chemical and absorptive scrubbing. The VOC’s are transferred into the aqueous phase and immediately partial oxidized, hence their solubility in water will increase. Practically any organic contaminant that is reactive with hydroxyl radical can potentially be treated. A wide variety of organics are accessible to UV/advanced oxidation like hydrocarbons, chlorinated hydrocarbons and esters used as industrial cleaners. As nearly all chlorinated hydrocarbons are not biodegradable, UV oxidation is the most effective way to destroy such components. The advanced oxidation of the VOC leads to higher oxidation products and partial to CO2. Oxidized products and by-products are now biodegradable and no more toxic. The sorption achieved in the scrubbers is higher than 98-99%. The mineralization to CO2 + H2O is between 20 to 60%. The grade of mineralization can be chosen.

The Enviolet® – UV –Oxidation applies the highest process reliability due to well developed and experienced technology and process control.

It is stable in performance and not sensitive against contaminants like catalyst-poisons, heavy metals, etc.

The optimized process leads to lowest possible running costs as the ratio of price/performance of the investment is the best.

Enviolet® Technology is in the application process for becoming declared as the BVT (best available technology).

Industries, VOC Emissions / Chemicals Removed, and Applications:

Industry	VOC's / Chemical's Removed	Application
Aerospace	PCE, TCE, MEK, Specialty Chemicals	Adhesive, Painting, milling, Machined parts cleaning & Degreasing
Composite Fabrication	Styrene, Acetone	Boat building, Bath Fixtures, Spas, Aerospace
Electronics, Computers	Specialty Chemicals, Acetone, MEK,	Chip, Disc, Recording Media, other manufacturing
Finishing / Paint VOC	Xylene, Toluene, Acetone, MEK, IPA, Methylene Chloride	Paint Booth Spraying, Stripping, Other
Grain Processing	Hexane, Ethanol	Grain mills, Fuel production, Alcohol, Oil extraction
Packaging	PCE, TCE, Acetone, IPA, MEK	Adhesives use, Painting
Pharmaceutical	Methylene Chloride, IPA	Pill Coating, Extraction
Photography, Film Processing	Methylene Chloride	Film washing
Printing	Thinners, Solvents	All Printing Applications
Remediation	PCE, TCE, BTEX, others	Off-gas from air strippers, spargers, Soil Vapor Extraction (SVE)
Wood Products	Formaldehyde, Methanol	Press Vent VOC control

Enviolet® UV-Oxidation versus other waste gas control

VOC Treatment Technology	Residuals / Byproducts	Disadvantages
VOC Absorption	Waste water, chemical sludges	Limited to soluble compounds, liquid absorbent may be transferred to the exit gas
VOC Condensation	Compound not destroyed, has to be hauled off site, may require hazardous waste handling.	Limited to low range of compounds at high concentrations. High energy consumption.
VOC Adsorption(TSA, PSA)	Spent adsorbent such as activated carbon which has to be hauled off site, may require hazardous waste handling.	Limited to low concentrations, not suitable for high humidity air streams. Sometimes high energy consumption.
VOC Thermal oxidizers / VOC catalytic oxidizers	Forming of HCl, products from incomplete combustion	Not suitable for low concentrations, H2S Can damage catalyst. High energy consumption.
VOC Biofiltration / VOC bio trickling filter	Leachate disposal, packing media disposal every 2-5 years	Moderate biodegradable emissions, large footprint, not used for chlorinated solvents.