Slurry Valves used on Mixing Tanks

The ceramic elements are used in high temperature air filtration for incinerators, biomass, and product recovery. Some of the industries these ceramic elements are used in include renewable energy, energy-from-waste, metals & mining, and product recovery.

The manufacturing facility of hot gas elements was originally developed for the aluminium industry to solve an issue of fires happening within the filter bag housing. Sparks were being carried over in the gas stream and setting fire to the carbon collected on the fabric filters. This company’s filters were developed using high temperature fibres and are designed to work in the same way as traditional fabric filters but with much higher temperature capability and resistance to sparks.

How the Slurry Valve Assists with this Application

The valves on the top of the tanks are positioned vertically, on a water feed to an inlet tank, and there are also horizontally installed valves at the bottom, on a slurry feed to the vacuum forming press. Both valves are normally closed, and controlled via air using a diaphragm pump.

The types of media passing through the valves are water on the inlet to the mixing tanks, and ceramic fibre slurry on the outlet of the mixing tanks. The job of the slurry valves is to isolate the mixing tank intermittently between mixes. 24vDC solenoid valves are used to operate the Pinch Valves.

Both media are ambient in temperature, with 3 bar air pressure used to shut off the air operated valves for slurry. Each Pinch Valve performs approximately 20 cycles per day. The elliptical shaped Pinch Valves from AKO UK open/close in the same position every time, prolonging the rubber sleeve and ensuring that 100% shut off is achieved.

Pinch Valve used within this application – VMP050.03X.72

VMP model, air operated, POM body, POM BSP internal thread end connections, natural rubber sleeve.

Pinch Valve for Slurry vs. Ball Valve

The end user of the mixing tanks informed us at AKO UK that they had previously used Ball Valves within this process, but found them more prone to clogging with the ceramic fibre product that they use. The ball valves were not opening/closing fully, thus restricting the flow and causing issues with production. Since using the Pinch Valves in comparison, they have found them to be quick acting, and much more easier to control. The Pinch Valves also do not clog as they have a self cleaning rubber sleeve and always a full 100% unrestricted bore.

The company have continued to successfully use Pinch Valves within this application for 20+ years, and class these slurry valves to be very good.

Maintaining Slurry Valves

Within this application, the rubber sleeves inside the slurry valves are replaced every 2-3 years. Replacing the sleeve inside AKO UK Pinch Valves is a quick and stress-free process. With the help of AKO’s re-sleeving videos and written step by step instructions, you are covered, by maintaining the valve with confidence.

When a new vacuum forming line is installed, there will be a further requirement for Pinch Valves at this site, since the company has so much successful experience with them.