When a quicklime and hydrated lime producer was looking for a high-tech delivery system to demonstrate its new high strength liquid lime product, a lightweight yet robust pumping solution was sought. They settled on a high flow dosing/metering peristaltic pump unit. The company is now able to supply the lime to its customers with a field trial equipment package tailored to specific needs.
Neutralac SLS45 high strength liquid lime from Lhoist UK Ltd, a Quicklime and hydrated lime producer, is used in process plants requiring improvements in their effluent treatment procedures.
Manufactured in the UK using patented technology, Neutralac SLS45 contains 45% solids and is designed for treating acidic effluents of all types. It is optimised for rapid acid neutralisation and pH adjustment. In many cases, the use of Neutralac SLS45 improves metal precipitation, flocculant stability and filter cake moisture content and porosity. It can also reduce the consumption of polymers and polyelectrolyte reagents in most effluent treatment plants. It is suitable for use in DAF Plant, metal precipitation, animal, food and dairy industry effluents, and treating all acidic waste streams.
Low grade commoditity
According to Product Manager, Derek Thompson, Lhoist developed Neutralac to address the fact that lime is often seen as a low grade commodity.
“Neutralac is different,” he states. “It allows us to attack the caustic soda market at the high end of effluent treatment. Here, neutralising agents such as caustic soda and magnesium hydroxide are aggressive and can easily damage both operators and plant, hence a comparable alternative is highly desirable. Neutralac is safer to use than caustic soda and other alkali alternatives, with equal or better performance.”
The Lhoist Group has operations throughout Europe and America, with a total headcount exceeding 7000. Around 100 are employed in the UK, at a quarry near Buxton and at a satellite site in Cumbria. Lhoist invests heavily in R&D, and Neutralac is among the latest products to make the transition from laboratory to production.
“We knew we couldn’t just sell it in bottles or IBCs and expect sales to take off,” explains Mr Thompson. “We had to take it to customer plants and provide delivery and analysis equipment on site. As a result, a lightweight yet robust pumping solution was sought.”
Lhoist is now able to supply the lime to its customers with a field trial equipment package tailored to specific needs. The pump used is a Watson-Marlow 720UN/RE high flow dosing/metering pump and Lhoist has already acquired six since the project commenced in 2012. “We selected a peristaltic unit because they offer the easiest and best way to pump slurry around,” says Mr Thompson. “Neutralac lime suspension is fairly thick and the pumps are often sited outdoors”.
The service and technology offered by Lhoist means that a company such as a metal finishing plant, for example, where strong acids are used to etch metals prior to plating, can now process its effluent stream easily and cost effectively. Lhoist will arrive on site with a ready-to-go system comprising Neutralac, pH control and delivery equipment, essentially supplying a small, pilot-scale effluent dosing plant.
The 720UN/RE is used to pump Neutralac from storage vessels into effluent treatment plants for pH control. Flow rates vary from 10 to 1500 l/h, which is controlled via a 4-20 mA signal from a pH meter. Run-times vary tremendously but, according to Mr Thompson, the impressive performance of the system often imparts a reluctance to change. As a result, the plant is retained, leading to ongoing sales of Neutralac.
“Our system tends to knock the customer for six – such is its performance that they don’t know what’s hit them by the end of the first day,” says Mr Thompson. “There isn’t much that can compete with Neutralac, particularly in combination with a high-tech delivery system. We can flat-line a plant’s pH and ensure legal allowance limits are not exceeded.”