Eliminating the build-up of moisture is an ongoing challenge in the mining and offshore sectors, where the harsh and hazardous environments make it daunting to maintain the integrity of key infrastructure and equipment, which needs clean and dry air to operate efficiently.

“Condensation and corrosion can disrupt operations such as mining and oil and gas extraction,” says Australian gas separation equipment manufacturer Oxair chief engineer David Cheeseman.

Oxair supplies desiccant air dryers that can help combat condensation in pipelines and keep machinery running for longer in mines without the disruption to production caused by major maintenance. For underground mining operations, clean and dry air is vital. In addition to affecting energy bills and production costs, contamination can result in poor performance of equipment, breakdowns, corrosion of parts, failure of air cylinders and solenoid valves as well as damage to air tools.

Oxair, which also supplies oxygen generators and nitrogen systems as a safer and more reliable alternative to cylinders, says its high-performance desiccant air dryers provide mines and offshore platforms with a clean and consistent compressed air supply to protect pneumatic instruments and keep pipeline applications as dry as possible, thereby extending their lives.

A typical desiccant air dryer pays for itself in less than a year by reducing and eliminating maintenance costs and downtime, while having less impact on the environment by reducing transport emissions through service call-outs and the disposal of broken parts.

“The flow rates of our equipment for generating instrument air are quite phenomenal and they can be customised for offshore lifting to a platform. With a desiccant dryer, machinery has a better chance of running at peak efficiency and surviving longer without major maintenance than it would without this essential equipment,” Cheeseman claims.

Desiccant dryers pass compressed air through a pressure vessel with two towers filled with an alumina desiccant bed. This material adsorbs water from the air and the bed becomes saturated and is regenerated in the next cycle. The dryer is timed to switch towers based on a standard timing cycle. During drying some compressed air is used to purge or dry the depressurised desiccant offline bed.

Another advantage that Oxair’s twin-bed system has over its competitors is the gentle cycle turnover, which allows it to continue getting air through the dryer when swapping over beds, unlike many other systems where the pressure drops slightly for a short period.

Offering a smaller footprint, flexibility and ease of installation, Oxair can supply different types of air dryers, available in both electric and pneumatic control formats. All of these dryers are controlled by means of a programmable logic controller with a reliable human-machine interface touchscreen.

The company also offers conversions on customers’ own air-drying equipment. Additionally, Oxair manufactures larger 25 bar to 30 bar dryers in a certified lifting frame of up to 10 000 standard cubic feet a minute.

Ideal for pipeline maintenance and other offshore activities, Oxair’s air dryers can be skid-mounted. They provide a cost-effective solution for ensuring a continuous stream of dry air safely on site in a range of remote locations and harsh environments, including Zone 1 requirements which have an explosive atmosphere for more than 10 h/y but less than 1 000 h/y.

Oxair also designs and manufactures nitrogen pressure swing adsorption systems up to 1 000 Nm³/h.

Additionally, Oxair designs and manufactures heatless desiccant-type regeneration dryers and filtration packages for a variety of industrial sectors including medical, gold mining, water treatment, oil and gas, food, chemical and biotech. The dryers can be skid mounted or in a lifting frame certified for offshore lift if required.

The company also produces pressure vessels, skid fabrication and process piping.