State of the art and potential to reduce VOC emissions from surface cleaning

November 1999
Report on the Umweltbundesamt (German Federal Environmental Agency) UFOPLAN-No. 297 44 906/2
Winfried Schwarz

The political context of the study is the EC VOC solvent directive (VOC directive) that will be transposed into German law within the next two years. This research report gives up-to-date statistical data on surface cleaning with halogen-free organic solvents and also determines the potential for VOC emissions reduction on an operational level. Altogether, about 63,700 tonnes (t) of fresh solvents made of inflammable hydrocarbons (HC) are supplied to facilities every year for surface cleaning purposes in six different sectors. In 1998, halogen-free organic solvents for surface cleaning were used and emitted as follows. About 49 percent, or 31,150 t, were emitted into open air during use. The other 51 percent became waste and were disposed of in different ways. Of the 32,550 t of used cleaning solvent, about 6300 t were recovered for reuse and were a part (10 percent) of the annual supply. About 2300 t were processed for other purposes. Slightly more than 1000 t (oxygenous HC derivates) were rinsed into the sewage system and did not decompose until they reach water purification plants. Most of the used solvents, about 23,000 t (70 percent) were burned for energy consumption..

Complete realisation of the VOC directive's limit values can reduce VOC emissions from surface cleaning at installations by 8310 tonnes, especially in the sector of metal degreasing. This is nearly 27 percent of the present total emissions of 31,150 tonnes per year. This figure increases to about 32 percent when it is adjusted to exclude the applications that do not fall under the VOC directive's surface cleaning category. Adjusted additional technologically feasible reductions not required by the VOC directive amount to 5250 tonnes, or 17 percent. Thus, the potential to reduce VOC emissions in surface cleaning amounts to nearly 50 percent.