In Fredericia, the overriding objective is to keep the Little Belt clean, and Fredericia Wastewater and Energy A/S has commissioned a new chemical dosing system (in recyclable thermoplastic) to secure future wastewater treatment for the area. The future-proofing includes, among other things, bringing the installation into legal compliance and meeting requirements for safety, the working environment, the UN Sustainable Development Goals, and other KPIs.
Per Dejgaard, who is a marine engineer at the plant and has more than 7 years of experience at Fredericia Wastewater and Energy A/S, was one of the driving forces behind the acquisition of the complete chemical dosing system. The specific considerations around the acquisition began in 2017, when a project collaboration was initiated with IWAKI Nordic A/S and the alliance partner Weber Kunststofftechnik in Germany. The system was commissioned in 2019.
In an interview, Per speaks very enthusiastically about the acquisition, which included a 30 m3 chemical tank, a filling station for it, as well as a dosing cabinet and associated measurement cabinets. All manufactured in PE100RC thermoplastic.
The system, which is used in connection with phosphorus removal in four large tanks, is connected to online meters and thus ensures correct dosing at the right time and place. Everything is handled separately for each tank to keep chemical addition to a minimum and the process at a maximum, so that the discharge requirements can be met.
Pumps, valves and monitoring are controlled from the treatment plant’s SCADA system and operate according to Fredericia Wastewater’s in-house developed dosing algorithm.
Per explains that the chemicals (PIX 113) are delivered by tanker truck. When the tanker truck arrives at the plant, it is connected to the filling station, after which the valves to the tank open automatically and filling can begin. Monitoring on the tank ensures that the valves between the tank and the tanker truck close automatically when the tank is full.
One of the criteria when selecting the new equipment was that the chemical tank, etc. had to be made of environmentally friendly and recyclable PE thermoplastic. This is because it can be disposed of and recycled properly and responsibly. In fact, a study (Environmental Product Declaration) carried out for Teppfa by the independent research institute VITO shows that many thermoplastic types used to manufacture, for example, pipes actually leave a much smaller CO2 footprint than, for example, metal pipes when viewed over the lifecycle.
The chemical dosing system in Fredericia has replaced a temporary system with a fiberglass tank, dosing pumps, etc., where daily operation was based on manual measurement and adjustment of chemical dosing in the process tanks. With the new dosing system and Fredericia Wastewater and Energy’s control, the plant now operates automatically, using precisely the amount of chemicals required for the process to run optimally.
Now, after about a year in operation, the system receives nothing but praise from both operators and tanker truck drivers.
“We have a well-functioning dosing system with top-level safety, easy access, easy maintenance, and at the same time we have ensured that we comply with the legislation,” concludes Per Dejgaard.
