Acetate Products
Kalic produces cleaner effluent for world-class plant.
A LEADING CHEMICALS manufacturing and processing company is cleaning up its act, thanks to a Kalic liquid lime system from Buxton Lime industries.
The firm, Acetate Products, makes cellulose acetate and converts it to fibres and films for a variety of uses, including cigarette filters. The finished products may look simple enough but they are the result of a complex chemical process that produces an extremely variable mix of acidic effluent.
And it's a big challenge to treat the effluent. Lime dosing is needed to ensure the pH is correct before it's fit to be discharged into the sewer system.
Previously, Acetate Products used a hydrated lime slurry. But it has invested millions to ensure its operation at Spondon, near Derby, is the most modern cellulose acetate plant in the world. It wanted a lime dosing system to match.
"We upgraded to Kalic because we required a highly reliable and accurate control as we only have one shot at getting it right," says Gary Edwards, Acetate Products' project manager. "We wanted a self-contained, simple, standalone liquid lime dosing system to give pinpoint pH control."
Kalic met the brief spot-on. Made from a natural material, it's a non-toxic, non-corrosive and cost-effective calcium hydroxide suspension that's easy to handle. And it has proved its worth across several industries from metals production to food processing and the treatment of drinking water.
Acetate Products received plenty of help from Kalic's manufacturer, Buxton Lime Industries. Buxton lime offered advice on the best location, design configuration and programming for the 77 tonne capacity dosing plant.
"The Kalic test rig proved very useful to establish the dosage rates and programme control," says Edwards. "It allowed us to set the control parameters close to what we wanted and achieve a smooth changeover to the new plant."
The Kalic system at Acetate Products runs continuously and has the capacity to treat up to 1000 cubic metres of effluent an hour. It is a fully-enclosed, modern process that doesn't give rise to dust or other emissions.
"Kalic is easy to handle and it mixes very well, providing a much-improved reaction rate and a cleaner effluent," says Edwards. "Dosing is more accurate and fewer resources are needed."
Buxton Lime's reliability and flexibility on delivery also impressed the company. Acetate Products' senior buyer Richard Chantler says the upgrade to Kalic has led to some increased product cost. But this is balanced by greater efficiencies in power consumption, reliability and resources.
Above all, he adds, "our effluent discharge is more reliable, which has reduced the environmental hazard and the risk that the Spondon site could break its effluent agreement with the local water utility company."
Editors' notes
Kalic Liquid Lime represents a major advance in lime-based treatment for acidic effluent, drinking water and waste water. It is extensively used in industries such as water and sewage treatment, food processing, pharmaceuticals, steel production, oil and agri-chemicals.
Kalic's key selling points are technical superiority and cost-effectiveness.
Its fine particles provide a stable suspension and large surface area that make it highly reactive and extremely efficient. It is safer than caustic soda. Also, its costs are lower, for handling, protection, plant maintenance and environmental protection. Kalic complies with current and predicted safety and anti-pollution legislation.
Kalic can help protect tanks, vessels, valves and pipework from corrosion. Its low freezing point (0ºC) reduces the need for lagging and trace heating of pipework, pumps and tanks. It is also easy to pump, handle and transport.
Kalic was introduced in 1997. It is made by Buxton Lime, the largest producer of lime and lime products in the UK and of the Tarmac Group. Buxton Lime's base in Buxton, Derbyshire is sited on an abundant supply of pure limestone.
