Aggregate Industry Case Study: LafargeHolcim Group: Aggregate Industries, Manchester Asphalt Plant

Expel has reduced the sites energy bills, saved the cost of maintenance and production downtime by eradicating the source of the problem from compressed air lines.

About the customer

Aggregate Industries is a proud member of the LafargeHolcim Group, which is the leading global building materials and solutions company with around 70,000 employees in over 80 countries.

Aggregate Industries produce and supply an array of construction materials including everything from aggregates, asphalt, ready-mix concrete and precast concrete products. Additionally, they produce, import and supply construction materials, export aggregates and offer national road surfacing and contracting services. They operate 200 sites and employ around 3,700 people.

Project Background

Asphalt plants are particularly susceptible to dramatic temperature changes across different points at a site. For instance, the temperature next to a hot burner is going to differ to the temperature at the top of a wind exposed silo. When such temperature changes occur, it is extremely common for moisture to be present in the compressed air lines which causes a whole host of problems, all of which act as a hinderance to overall site efficiency and equipment performance. The Manchester Asphalt site has no different from this scenario and they were experiencing problems caused by compressed air contaminants like liquid water, oil emulsion fluids and solid particulates in the compressed air lines especially in the winter months.

Plant Manager Dave Owen reported that the bitumen area is particularly exposed to the elements. The water would then freeze in the lines when it gets cold, causing ice blockages and expensive equipment replacement and/or repair costs. Further problems caused by moisture in the airlines were occurring by the solenoid control panel, which would cause faulty operation of the valves. This is because trapped moisture causes corrosion inside the actuator and solenoid bodies and can hydraulically lock the piston at part-stroke and stop the valve from turning.

Why did Aggregate Industries choose Expel?

High on Aggregate Industries’ priority list is to be a leading sustainable business. Plant Manager Dave Owen is exceptionally proactive in this matter and is very keen to reduce energy usage at every site under his management. Expel is the first ever compressed air filter which can improve the sustainability of compressed air usage.

Unlike standard compressed air filters, Expel does not require any replacement filter elements. This eradicates the wastage generated by traditional filters as well as saving the need for maintenance companies to come and service these filters. Additionally, as the internal elements of traditional filters become saturated, they gradually become more and more energy draining because a greater volume of compressed air is required to pass through the filter elements. In contrast, Expel has a consistently low pressure bar drop (it will never exceed 0.1 bar) because rather than retaining any liquids or solid particulates it will instantly pass these contaminants into an automatic drain. This means energy usage will also remain consistently low and will never increase over time.

In addition to the sustainability aspects of Expel, the Expel compressed air filter offers a far superior solution to the problem of liquid water, oil emulsion fluids and solid particulates in compressed air lines. This 3-in-1 solution has eradicated all problems the site was experiencing with the airlines. By installing one Expel unit at point of use in the bitumen area, the site no longer experiences issues with water freezing causing ice blockages. Another Expel unit was installed prior to the solenoid control panel to ensure they are adequately protected against damaging liquid water, oil emulsion fluids and solid particulates.