The use of a VACUDEST vacuum distillation system makes an important contribution to meeting these new requirements. This technology enables a recirculation of the treated process water and is also enormously efficient due to cost savings in various areas. A look into the production illustrates these advantages: During component cleaning, galvanic coating processes and crack detection, a wide variety of process waters are produced in the aviation industry, which have to be disposed of at high costs. The VACUDEST vacuum distillation system can efficiently treat both individual streams and mixtures of these different process waters. The distillate can be recirculated and thus recycled in many application examples. This reduces the environmental impact enormously. Due to the drastic reduction of disposal costs, the annual savings potential is also very high.

Excursus: crack detection

By means of dye penetrant methods, surface defects in metallic materials can be detected very quickly on components. This method is mainly used for the inspection of welds and components in the maritime, aviation and automotive industries as well as in apparatus and container construction. A distinction is made between colored and fluorescent penetrant inspection. The fluorescent inspection, which is particularly common in the aviation industry for safety-relevant parts, is carried out under UV light with fluorescent penetrant. Defects such as cracks can thus be easily detected without the component being damaged or destroyed during the inspection. The increasing quality standards in the aviation industry require this type of material testing.

Best distillate quality through patented Clearcat technology

The principle of vacuum distillation is an excellent method for the treatment of wastewater containing oil. This also includes process water, such as crack detection, cleaning and degreasing water, which is produced in the aviation industry. In the past, vacuum evaporators were able to separate salts and heavy metals reliably, but over-distillating hydrocarbons and oil components caused problems. These impurities had to be laboriously separated by additional process steps. he Clearcat technology enables a COD reduction of over 98 percent. The patented Clearcat technology reliably separates these organic contaminants while still in the plant and significantly improves the distillate quality – the distillate is crystal clear and oil-free. A very low hydrocarbon index can be guaranteed. The COD value (chemical oxygen demand) caused by oils, a measure of the organic pollution of the water, is reduced by up to 98 percent. This represents an improvement of 60 percent compared to single-stage distillation. In the process water analysis that follows, this reduction is even exceeded.

Circulation with VACUDEST in the MRO industry

A sample from an MRO company examined in the laboratory shows that the process water treated with VACUDEST can be recirculated and thus reused in production. Also a discharge into the sewer is possible in any case, since the distillate meets the qualitative requirements of the authorities. In the case study the examined mixture of crack test and cleaning water can even be concentrated up to a remainder of only less than 2 per cent. Measured against a total amount of process water of 3,000 cubic meters per year, this corresponds to only about 60 cubic meters. Accordingly, around 2,940 cubic meters can be sustainably recycled. Physically, 99.9 percent of the heavy metals are separated, so that the discharge limits for heavy metals are reliably met. A good indication of the presence of salts is the conductivity. This was determined in the case study with only 6 µS/cm. The distillate is therefore salt-free. The other measured parameters also allow the distillate to be reused directly in the production process. Besides the low conductivity, the COD value is also greatly reduced. The almost pH-neutral distillate is therefore ideally suited for reuse in various production processes. In this way, costs can be reduced by 98 percent: On the left, process water from aviation, in the middle the treated distillate by a VACUDEST system with Clearcat, on the right the minimized concentrate. Vacuum distillation using VACUDEST is a sustainable and efficient solution for wastewater treatment in the aviation industry. The distillate meets the strict quality requirements of the aviation industry. Depending on the specific requirements of the customers, the distillate quality can be further optimized by using downstream technologies such as ion exchangers or UV treatment.