A clean water pump was also provided by Verder to deliver the end product back to drain or for recycling on the site itself. The customer specified the system for the provision of effluent form printing presses, known for heavy degrees of inky, starchy residue, paper mash and particles. However, following the initial success of the system the customer has now widened the scope of site to incorporate effluent from a range of industrial processes.
Verder pumping services
The Verder Project Team provided the designs for the system, advising on the best way to handle both the initial effluent and subsequent changes in fluid states as the effluent went through the treatment cycle. The Verder team provided installation and commissioning services at the site, assisting with the training of the staff for operation and periodic maintenance. For the provision of spares, advice was given on stock inventory for critical parts to prevent unnecessary downtime without holding an excess of parts.
A project manager liaison supported the design and installation with regular site visits to ensure the planning and budgeting of the project remained on track. A full drawing and certification pack was provided with technical and engineering support.
The future relationship between Verder and the company is developing with the increased automation of the plant, with the project team advising on actuated valves and applying their knowledge of process control systems to minimize the involvement of manual labour and provide a consistent method of effluent treatment.
The pumps and system incorporated at the sites were designed, manufactured and tested at the Verder Service Centre, based in West Yorkshire. This allows direct cooperation between Verder service technicians, R&D engineers and our external sales engineers creating better products and design and a high level of quality control to multiple ISO standards.
Transfer of industrial effluent streams in a waste processing facility
An established waste management company who provide services to principal contractors, public bodies and direct with industry was seeking an expansion to provide a new service to businesses in the Yorkshire area.
The new service was set-up to meet a new demand in the volume of effluent from industrial processes such as print works, collections from road cleaning tanks or leachate from landfill sites. Much of this demand stems from the drive for meeting compliance targets set by the Environment Agency and the prohibitive cost of developing and building a facility onsite capable of efficiently processing effluent to remove solids, neutralise chemicals and prepare the inputted media ready to be returned to drain. This may involve chemical dosing, ultra high filtration through membrane systems and crucially, discharging a water stream that is compliant in BOD and COD levels and acceptable to the environment and wildlife.
The process
A new site was selected with an investment of £11m with an initial contract from a large printing press producing a high volume of effluent. As part of this site, the waste is passed through a series of tanks, pipework and filtration devices. At each stage of the process a slurry or sludge of solids and fluid in different proportions is required to be transferred. This places demands on the pumping system with solids potentially causing clogging and abrasive wear. An additional factor is the varying viscosities and S.G of the fluids as well as trace chemicals.
The effluent media arrives via one of the company’s or 3rd party tankers to be offloaded into an initial tank where sediment and larger solids are allowed to settle before being transferred to a settlement unit.
Following the separation of the suspended solids by the filtration device, a scavenger pump then removes the dewatered sludge and the filtrate is then transferred to a holding tank where up to 20.000 L is stored, ready for ultra fine filtration through a membrane system. The filtrate is then pumped back to a holding tank, where it can be chemically treated and made ready for it to be released to drain or be recycled as a diluent for the effluent at different stages of the treatment process.
Verder were approached to provide the pumps, pipework assembly, control panel and peripheral items such as ultrasonic sensors, filters and bauers. With experience in solving pumping solutions with difficult fluids such as in AD & Bio gas facilities and sewage treatment works, Verder won the contract. This was a new process for the company and the Verder Project Team were part of the research and development to ensure the site would be able to handle the treatment cycle in an optimal and cost-effective way.
A pumping solution was required to handle multiple slurry-type fluids and at the heart of this is the Verderhus screw-channel pump. The range features an open-channel screw impeller which allows the passage of slurry and sludge up to 3000 cPs and solids of up to 160 mm which would be capable of both handling the print effluent and the effluent from many future clients.
For the transfer of the raw product from the effluent reception tank to the settlement unit, a Verderhus 80-50 was installed. This model is capable of handling up to 40 mm solids and flow of up to 25m3 p/h. The pump was installed vertically, utilising the suction feed from the large tank to provide a flooded state. As the pump finishes transfer of the tank, any remaining solids fall from the pump and back into the pipework, preventing clogging of the pump for future batches. The screw-channel impeller offers a BEP of up to 70%, even with the 2 mm solids the pumps are required to handle.
As the settlement tank is drained, the sediment and small solids which remain are removed by a scavenger pump. Verder selected a Verderflex Dura 25 peristaltic pump to provide the working principle necessary for handling highly viscous sludge with a high proportion of abrasive solids. The sludge was rated at up to 13,000 cPs with 5% fine solids, which is a common fluid-type for a peristaltic. Featuring a compressible hose, the sludge is drawn into the pump by a rotor. The sludge is moved within the hose by the rotor and discharged. As the fluid is contained entirely within the hose and no moving parts subject to abrasive wear from the media, the pump is extra resilient to the bottom slurry of the settled unit.
5 further Verderhus pumps were used for the transfer of the slurry and dirty water applications with both 80-50 and 100-100 size configurations for the degree of flow and head required. The subsequent processes were transfer applications of the settlement filtrate to a holding tank and process feed tanks. The Verderhus also returned the filtrate to these tanks for dilution of the slurry for efficient movement of the effluent around the site. The Verderhus pumps were specified to handle up to 200 cPs. This would be towards the upper limit of a regular centrifugal pump with traditional vane impeller. The energy draw to maintain the head and flow capacities would mean an oversized pump or a very inefficient working principle, causing energy costs to increase.