Sustainable and economical wastewater treatment

MAN Nuremberg is switching to environmentally friendly vacuum distillation. The result: a three-fold better cleaning of their cooling lubricant emulsions and parts washing water as well as lower operating costs.

A more environmentally friendly solution for MAN

Within the MAN Truck & Bus Group, the MAN site in Nuremberg is the international competence centre for the development, production and sale of diesel and gas engines with an output range from 37 kW to 1,397 kW (50 hp to 1,900 hp).

MAN engines have always been a reliable source of power for the Group's own MAN and NEOPLAN trucks and buses. In addition, they also go to work with all their energy in road and rail vehicles, yachts and work ships, power generators and combined heat and power units, construction and agricultural machinery.

During the production of many of the required components, approx. 4,000 m³ of cooling lubricant emulsions and parts washing water are produced annually. These were previously separated using an ultra-filtration plant and the treated wastewater was then discharged into the public sewer system. Here MAN was striving for a more environmentally friendly solution. The company decided to optimise the process and to ensure a sustainable treatment of the process water produced. For example, a call for tenders was launched in search of newer and more efficient methods. H2O GmbH from Steinen in Baden offered a VACUDEST vacuum distillation system individually adapted to the requirements.


Highest distillate quality with the H2O Clearcat system

The analysis of the customer's process water in H2O's own laboratory confirmed that the treatment using the vacuum distillation can be successfully performed. These results were the first step in the right direction. The quality of the results in the laboratory also exceeded the strict requirements at MAN.

The evaporation rate also showed the customer that he only has to dispose of 2.7 % of waste from his process water and can expect a concentration of almost 1:37.

Vacuum distillation with VACUDEST is a very efficient separation process for separating high-boiling impurities from industrial process water. Nevertheless, certain physical effects prevent oils in particular from being completely separated by distillation and lead to traces in the distillate. This effect is known to all plant manufacturers and can often lead to a clouding of the distillate. Common after-treatments are based on coalescence separators and activated carbon stages. In addition to the running costs, there is also the follow-up treatment.

Not so with the patented H2O Clearcat system - it guarantees highest distillate quality without the use of the usual follow-up treatment and consumable materials. This additional option for the innovative VACUDEST vacuum distillation system allows the safe and efficient treatment of industrial waste water containing oil and grease in a single process step. The operating principle of the Clearcat condensation stage is based on physical and catalytic effects. Therefore, this cutting-edge technology requires neither energy nor auxiliary or operating materials. H2O improves the quality of treated water and sets new standards. In the end, H2O also convinced the responsible employees at MAN Nuremberg.


Covering Avoidance instead of Covering Treatment

Another decisive factor for the VACUDEST plant were the lower operating costs due to the simple chemical cleaning. Everyone knows the problem with the iron or coffee machine: Hardeners in water and other impurities can occupy the heat exchanger and ensure increased energy requirements and additional expenditure for maintenance and cleaning. With vacuum evaporators, the risk is many times higher. Although chemical rinsing equipment can often delay cleaning, it can only completely replace it in a few cases. The proven Activepowerclean technology helps here:

Activepowerclean stands for a technology development that uses small (6 mm) ceramic balls for continuous heat exchanger cleaning. Due to the natural circulation of the process water in the heat exchanger, the ceramic beads are constantly "boiled along" and clean the surface during the process. So this applies: Coating avoidance instead of coating treatment!

Mr Neumann, head of media supply at MAN, and Mr Klein, project manager at MAN, were very enthusiastic about the performance and treatment from VACUDEST and hope for many years of successful environmental protection and that MAN could decide in favour of recycling in the future.