Good practices in CP: 3. Reducing organic solvent emissions and elimination of hazardous waste (FAMED Żywiec)

Cost (implementation of good practice): Medium

Description of the problem: 

 

The company's manufacturing processes require that the surfaces of manufactured parts be thoroughly cleaned before paint coatings are applied on them. The technological processes used in the preparation and application of paint coatings on parts were a source of negative environmental impact – high emissions of volatile organic compounds into the atmosphere and the generation of large amounts of hazardous waste. Prior to modernization, steel parts were degreased in trichloroethylene vapor. The volume of trichloroethylene emissions from this operation was 0.716 Mg/year, which translated into annual trichloroethylene consumption of 1,500 liters.
The process of painting steel surfaces was a wet process, using phthalic paints. Annual consumption of paints (about 320 kg/year) and their solvents (about 340 kg/year), resulted in VOC emissions of about 0.490 Mg/year with single-shift operation.

 

 

Modernization of the surface degreasing process prior to painting and installation of a modern powder coating plant.
 

 
As part of the modernization, the process of degreasing surfaces in trichloroethylene vapor (the so-called TRI washer) was replaced by degreasing operations in a Finnish washer and rinsing on a so-called washing line. These operations are carried out in aqueous, low-concentration and low-temperature preparations.  The Finnish washer is a closed device and is not a source of environmentally harmful emissions. On the other hand, the washing process carried out in the washing line, where elements are washed, rinsed and passivated (temporary corrosion protection) results in negligible emissions of pollutants into the atmosphere (ethylenediamine 0.008 Mg/year).
 

Installation of a modern powder coating plant
 

The wet painting process has been replaced by powder coating process. This process does not emit pollutants into the atmosphere. In the paint shop, components for hospital beds are painted: from the tiniest drive systems to frames or beds measuring 200 cm by 80 cm. The paint shop, operating in a single-shift mode, uses about 500 kg of powder paint per month. Due to the nature of the product, very different paint surface thicknesses are required: from 70 to 500 µm. The paint shop uses a cyclonic powder recovery system based on a double cyclone, ensuring very high efficiency in powder paint recovery. The separated powder is returned to the process. The paint line is an efficient machine, operating at speeds of up to two meters per minute.

Changes in technological processes related to the application of paint coatings involved:

• Replacement of wet painting with powder coating, implemented between 1995 and 2001.
• Elimination of organic solvents from the sheet metal pre-washing process – 1999.
• Elimination of trichloroethylene from sheet metal washing operations prior to powder coating – 2001.