Process pumps prove their worth in other sectors
3 Oct 2018
When a product proves itself in the process industry, it can open up other markets, as Watson-Marlow found when the effectiveness of its Bredel pumps provided the solution.
The many fuel stations situated around the UK have to deal with the substantial supplies of effluent waste they generate daily.
This issue has been exacerbated in recent years due to the growth in non-fuel services. Many sites on major routes now have adjacent hotels and a selection of food outlets. Consequently, the increased footfall at such locations leads to even greater quantities of effluent for disposal.
Yet a large proportion is not connected directly to mains sewerage. Due to logistically challenging locations on motorways, dual carriageways and trunk roads, plenty of UK stations rely on underground holding tanks for their effluent.
These tanks vary in size, typically from 15 to 25m3. When approaching full, the transfer of effluent waste into the nearest mains supply, which can sometimes be up to 50m away, presents the underlying challenge.
However, in many instances, the septic tank originally installed to serve the fuel station alone is now way under capacity.
Business impact
From a business perspective, a full septic tank means that toilets and washrooms have to close, along with any food outlets. As a result, revenue is lost and annoyed customers lead to a loss of reputation.
Regular external tank emptying is expensive, at around £600 a visit, so a more automated solution, based on the latest pump technology, provides a commercially attractive alternative.
However, some pump types are simply not suited to handling the objects that some people like to flush away, namely non-degradable wet wipes and nappies. Such items cause submersible pumps, which historically have been deployed at many UK fuel stations’ effluent treatment facilities, to suffer from ragging or blocking. This in turn leads to increased pump maintenance costs.
Regular external tank emptying is expensive, at around £600 a visit, so a more automated solution, based on the latest pump technology, provides a commercially attractive alternative
All of these issues had been duly noted by Adler & Allan, a leading supplier of environmental clean-up solutions that has long-standing maintenance contracts with multinational fuel retailers such as Shell and BP, covering a high number of service stations.
Proven capability
Engineers at Adler & Allan had seen Bredel pumps in action at a number of chemical processing sites that the company also serves. They also noted that one chemical company stated that: “Bredel is the only pump we do not have problems with.”
When the firm wanted to conduct trials involving the emptying of septic tanks at a select number of motorway service stations for which the company has maintenance contracts, the firm opted for Bredel hose pumps supplied by Watson- Marlow Fluid Technology Group.
Thanks to a suction lift of 3-4m for typical tank sizes of 3,000 to 5,000 litres, the Bredel 50 hose pumps fitted with abrasion resistant NR Endurance hoses cope with the task.
Lacking a rotor or diaphragm to obstruct, the ability to handle challenging solids and avoid issues such as ragging, ensures Bredel pumps are suitable for the task.
The pumps typically run intermittently at 10 rpm, providing flow rates of 29 litre/ minute in order to handle solids. Hi-lo tank level float switches determine when the pump operates to remove effluent from the septic tank and transfer it up to 50 metres away to the mains sewerage pipe.
Additionally, as the Bredel pumps are installed at ground level in kiosks/ enclosures, access is straightforward with no confined spaces or safety issues.
