Aggregate Industry Case Study: Aggregate Industries, Liverpool Asphalt Plant

“Expel is working well across the plant”

Phillip Rudd – Assistant Operations Manager – Aggregate Industries

The revolutionary point-of-use filter, Expel, stops problems caused by compressed air contamination for an Aggregate Industries site.

Project Background

Asphalt plants are prone to experiencing moisture issues in pneumatic lines because the air usually travels long distances and is exposed to rapid temperature changes across the plant.

Aggregate Industries’ Liverpool Asphalt Plant was no exception. Assistant Operations Manager Phillip Rudd said one of the most prominent areas experiencing problems with liquid water in the compressed air lines was on the mixing deck. The solenoid valves on the mixing deck control cylinders, which regulate the volume of each product entering the asphalt mixture. When liquid water damages solenoid valves, they stop functioning correctly and remain in an open or closed position. The malfunctioning valves would alter the ratio of substances in the asphalt mix. The team at the Liverpool site wanted a permanent solution to the problems they were experiencing with compressed air contaminants.


air compressor water traps

Why did the site choose Expel?

Phillip Rudd reported that Expel immediately stopped the issues with moisture reaching the solenoid valves on the mixing deck. As a result, the Assistant Operations Manager was keen to resolve the problems in other areas to stop equipment downtime.

The bitumen area relies heavily on pneumatic valves and is a common location where many asphalt sites experience moisture issues. As Expel is a point-of-use filter, Phillip Rudd installed another Expel unit as close as he could to the bitumen area to stop the frequent damage and faulty operation of valves controlling the flow of bitumen. The bitumen area was particularly problematic in winter because water would freeze in the compressed air lines, causing ice blockages. The team would then boil kettle loads of water to pour over the lines to help them defrost. While this stopped the ice blockage, the liquid water in the lines would still be in the lines, continuing to cause equipment damage.

By installing Expel, the team found that they no longer had to defrost the lines in the winter months. Expel continually ensures the lines are free of moisture.


Reduced Downtime

Reduced Maintenance

Reduced Costs

Reduced Wastage


[contact-form-7 id="6806" title="Contact form 1"]