Waste water occurring in the metal processing industry, is mostly low contaminated but can’t be disposed of into the public sewer. Thus it has to be disposed by expensive waste management companies or be treated on site.

In the metal processing industry, most of the manufactured parts have to be cleaned from residuals. In most cases these residuals consists of swarf, ash and clinker relics, as well as cooling lubricants or release agents from die casting.

These relics will then get removed by steam jet cleaning- or parts cleaning machines. Process and waste water that occurs after cleaning, usually can’t be disposed into the public sewer and has to be disposed of through expensive waste management companies, creating important costs. The Schelling Anlagenbau GmbH from Austria is a leading producer of woodworking-machinery like cut-to-size saws and cut-to-size plants.

The core part of the woodworking-machinery is a stainless table, where the plates are fixed precisely. During the production of these tables and some other units, the parts become contaminated and have to get cleaned prior tot be processed further.

Since the parts are quite big, a 16m long washing place is needed, where the parts are cleaned by means of a steam jet cleaner.

Due to the company's aim to act environment friendly Schelling tried to find a solution for cost effective disposal or treatment of the waste water. After careful analysis of systems available on the market Schelling GmbH decided to invest in an H2O water evaporation system - the VACUDEST^®.

Treatment with VACUDEST^® evaporation system
The unit, designed, produced and delivered by H2O GmbH, enables Schelling to treat the contaminated washing water by a VACUDEST^® 120 ClearCat^® directly at the washing place and recycle it after the evaporation process. Due to reduced amounts of waste water Schelling could cut cost dramatically. Due to the vapour recompression only 50 kWh/m³ of evaporated water are needed. This amount is about 5 % of the energy that is needed for evaporation under atmospheric conditions.

Unlike other processes, the VACUDEST^® needs no expensive chemicals for cleaning the waste water. This simplifies the reuse of the distillate (cleaned water). The distillate will also be free of heavy metals and salts which makes sure that there won’t be any residuals like salt- or limescale spots on the workpieces.

Crystal clear distillate with ClearCat^® technology
The new ClearCat^® technology is an innovative development of H2O for the treatment of water, containing oil and hydrocarbon (emulsions). With that method, you receive a high quality distillate which is crystal clear and virtually free of oil.

When treating process water, containing oil, in many cases legal limits for the hydrocarbon oil index have to be kept. Thanks to the ClearCat^® technology the oil content has been reduced to values below 10 mg/l in all cases so far. This result is a milestone compared to conventional evaporation plants available on the market.

With the ClearCat^® technology the re-use of the distillate is possible because no oil will be transmitted to the parts to be cleaned. Thanks to the ClearCat^® technology the Schelling Anlagenbau is able to paint the parts right after the washing process.

To keep the volume constant in the closed loop, the water, which evaporates partially, will be refilled with rain water. Due to low cleaning agent consumption as well as money saving by paying less disposal cost the VACUDEST^® is very economical.

There are more technical innovations of H2O, which are characterising the VACUDEST^® vacuum evaporation systems. For example the self cleansing heat exchanger ActivePowerClean. With the heat exchanger, the risk of fouling can be reduced.

As a result, less maintenance is needed and a constant heat transfer will be assured. You can achieve highest concentration factor possible, even if the waster water composition is changing frequently, due to patented, automatic detection of end of cycle.

Flexibility of capacity due to modular construction
The VACUDEST^® systems are available in 15 different sizes from 20 l/h to 2000 l/h. Due to the modular body of the machines, it is possible to upgrade the VACUDEST® if the actual amount of water is increasing.

Project management
After giving advice, an especially for Schelling designed solution has been developed, which fulfils their requirements. After supplying, the VACUDEST^® has been started up by an H2O technician.

After one year, Schelling Anlagenbau GmbH is still satisfied with the performance of the VACUDEST^® evaporator. The distillate quality, as well as the feasibility of the machine is excellent. In addition the workload to run the machine is lower than 1 hour per week.

H2O was able to meet all demands of Schelling Anlagenbau with their VACUDEST^® vacuum distillation unit, and like Mr. Guggenberger used to say: “We are very satisfied with the evaporation unit and the fact that we can contribute to our environment.