When a tank farm needed to expand, the option was for 12 centrifugal pumps or six VPS screw pumps. An ability to operate in reverse to load and unload tanks, and suction properties were the deciding factors in the final choice.
Since November 2017, Fristam Pumpen Schaumburg, based in Stadthagen, Germany, has been able to deliver orders in the areas of diesel, fatty alcohols and oils. Single-flow screw pumps offers solutions for tank farms pumping chemical and petrochemical products.
These pumps can handle many products from volatile petrol to viscous bitumen. To handle these tough environments, the pumps have been designed to be robust, efficient, flexible and are easy to maintain; irrespective of whether they are used as transfer pumps or for loading and unloading tanks and tank trucks.
Additional tanks To expand their tank farm capacities for fatty alcohols, one of Fristam Pumpen Schaumburg's customers put six additional tanks with the appropriate infrastructure with DN 100 pipelines into operation. There were two alternatives when selecting the pumps: one option was to install two centrifugal pumps per pipeline, one under the tank and one for each pipeline at the loading/unloading station.
The other solution relied on one VPS screw pump per pipe only, or rather per tank. This is possible because VPS pumps can be operated in reverse, enabling tank trucks to be loaded and unloaded with the same pump. What’s more, the suction properties and associated so-called ‘residues’ was an essential deciding factor in choosing the VPS pumps.
Less maintenance “Less pumping generally means fewer potential sources of interference and, of course, less maintenance and repair work”, the tank farm's operations manager explains. “Thus, the investment costs, which would have been about the same in both solutions, only played a minor role.”
The six single-flow VPS 4-5 pumps are equipped with a 30 kW drive and have been working flawlessly for more than a year. They are designed for a flow rate of 120 m3/h at a differential pressure of 4 bar and a viscosity of about 1 mPa s. “We haven’t had any problems so far. The decision to opt for the VPS pumps proved to be the right one. They run very quietly and smoothly, and we have even been able to shorten the loading and unloading processes by about 30%”, the tank farm operator continues.
Complete skids A tank farm for diesel products modernised its loading and unloading station for tanker trucks in the winter of 2017/18. To make the loading and unloading process as safe, quick, and simple as possible, the customer was looking for a complete system consisting of pumps, gas separator, filter and volume counters and finally settled on a skid from Fristam Pumpen Schaumburg. The skid consists of all the required components and was delivered ready for connection and immediate start-up.
"The station was put into operation within a very short time and ran without any problems,” says the customer's project manager. Two single-flow VPS 4-5 screw pumps with a 30 kW motor pump up to 250 m3/h at a differential pressure of 4 bar and a viscosity of about 4 mPa s. The redundant design of the pumps also safeguards operation in an emergency, since the second pump can continue to pump in the event of an accident. Other installations followed for biodiesel and additive blending, among others.
