Steam traps in comparison
Steam is money: Levaco Chemicals rely on EBE Engineering Venturi orifice steam traps
At Levaco Chemicals, process steam is the principal heating medium used in the reactors. To ensure that this valuable energy source is used as efficiently as possible, they now rely on ECOFLOW venturi orifice steam traps manufactured by EBE Engineering.
Levaco Chemicals has established its headquarters and production facility in the Chempark Leverkusen, which is a major industry centre in the local region. On this site Levaco produces various speciality chemicals such as dispersants, emulsifiers, wetting agents, defoamers and superabsorbents for numerous industries. Previously a part of the Bayer Group, Levaco, which now belongs to the Diersch & Schröder group of companies, can look back on more than 50 years of experience in chemical production.
In order to be successful in the market, Levaco is constantly working to improve its efficiency. Enabling them to offer speciality chemicals of a high standard at competitive prices. The company optimises its energy management by implementing industry best practices with the aim of identifying savings opportunities. Steam is one of the most effective factors to target as it is needed in considerable production volumes in the reactors. Steam energy is supplied by the chemical park operator Currenta. Savings in steam usage offer true bottom line savings, reducing direct energy costs in production. Any steam losses or a reduction in heat transfer efficiency on the other hand, lead to higher costs, poorer productivity in the reactors and higher energy requirements. This can be caused, for example, by poor efficiency in steam traps.
Deciding on a suitable thesis for a Masters degree.
Tom Hummel has worked as a plant Engineer at Levaco since 2014. He was looking for a suitable technical topic for his master’s thesis in industrial engineering at the University of Applied Sciences for Economics & Management (FOM), Essen. He decided to conduct a comparison between the ECOFLOW venturi orifice steam traps from EBE Engineering, which had never previously been installed in the company, and conventional float steam traps. “As a member of our company’s energy management team, I am constantly looking for ways to save energy. The steam trap comparison was an excellent project to balance the company’s objectives and my own.”
In total, 36 reactors are in operation on the site. Their capacities range from three to 25 cubic metres. One or two steam traps are installed per reactor, and a large number are also needed for the steam tracing systems. Altogether, more than 250 mechanical steam traps of various types (bimetallic, thermal, float) are installed in the steam system.
Significantly lower steam consumption
The venturi orifice steam trap project began by measuring the performance of the existing mechanical steam traps on one of the three largest reactors. For this, Tom Hummel began by identifying two products with a wide reference range. Both products were specifically chosen due to their different physical properties, in particular their viscosity. As a consequence the steam volumes required for the processes and the heating times were very different. This made it possible to investigate a larger operating range for the steam traps.
The reactor selected produces 27 different products with varying amounts of feedstock. The total annual tonnage of the 20-cubic-metre reactor is about 3,600 tonnes. The plant is operated with 30 bar steam pressure and consumes about 200 tonnes per year. In autumn 2019, a planned maintenance shutdown was used to install two venturi orifice steam traps. As the EBE ECOFLOW venturi steam traps comply with all European dimensional standards for valve installation, they were interchangeable with conventional mechanical steam traps.
In his comparative analysis, Tom Hummel found that the EBE ECOFLOW venturi orifice traps used an average of 22.4% less steam in the process than conventional mechanical traps for the first comparative product. For the second product, the savings were 18.8 %. Showing that for both products the use of the venturi orifice steam trap gave steam savings compared to mechanical float steam traps. This is due partly because venturi orifice steam traps do not have moving parts that can wear out, leading to greater steam consumption. “In fact, I expected the “new” type of steam trap to save steam beforehand. However, when I saw the actual measured values, I was surprised at the amount of steam saved,” said Tom Hummel.
Shorter heating times increase productivity
During the analysis, as part of the thesis, the venturi orifice steam trap also showed a reduction in the heating cycle time for the two products being investigated. Due to better steam energy utilisation, the processing speed could be increased and thus for batch operation the production volume could be increased. For the first product, an average time saving of about 27 min or 16.6 % was observed, for the second product the average saving was about 4 min or 11.3 %. According to Hummel, this could be due to the start up operation of the venturi orifice steam trap. Since the steam traps physical properties are those of a simple orifice when the condensate (water) is cold, the liquid is discharged from the heating coil faster and the steam can heat up the process faster. Another possible reason is that the continuous discharge of condensate through the Venturi steam trap allows the required heat energy to be introduced into the process more quickly, which also saves time.
Long-term investment and flexibility
“As we produce many different products, different mass flows of condensate can occur. In addition to the steam and time savings, the scale of the venturi orifice steam traps operating point is therefore also a very convincing advantage,” explains Hummel. This is because, thanks to the orifice and venturi operating range, it is possible to respond flexibly to any changes in the condensate mass flow that may arise during a product change. An additional plus point is the extremely short maintenance intervals of the venturi orifice steam trap and the integral filter – this keeps maintenance to a minimum. “EBE proved to be a very competent partner who were able to answer all the questions arising as a result of the thesis. EBE’s 10-year warranty shows that the company has confidence in its product” stated Hummel.
After the positive results, the venturi orifice steam traps are to replace existing mechanical traps on an identical reactor. Another factor contributing to the decision is that the venturi orifice steam traps lifecycle costs are significantly cheaper than the mechanical float steam traps. Due to the steam savings of the venturi orifice steam trap, the replacement will pay for itself after only about 1.5 years.
The steam traps in the second reactor will be replaced as early as April 2021. In the long term, it is planned to replace all defective mechanical steam traps on the larger reactors with ECOFLOW venturi orifice steam traps from EBE Engineering.