Pipeline Safety A Prime Focus For Challenges Of The Australian Environment

As one of the most urbanised and coastal-dwelling nations on Earth, Australia is increasingly  sensitive to spills of  chemicals, waste and other potentially harmful materials accidentally spilled in workplaces.

With around 90 per cent of our population dwelling in urban centres – well ahead of the US, UK and China, for example, and way above the global average of 52 per cent – Australia’s cities are particularly prone to the issues created by hazardous and polluting spills entering the environment through drains and watercourses leading to the sea, or seeping into the ground and contaminate the soil or groundwater.

The problem is also a major one also in our rural and outback areas, with industries ranging from agriculture to mining being heavily dependent on often scant and precious supplies of water where harmful spills are also a major source of concern to both State Environmental Protection organisations and to national bodies such as Safe Work Australia.

In response to such problems, Safe Work Australia has introduced a Code of Practice for Managing Risks of Hazardous Chemicals in the workplace.

The Code says companies must develop good handling procedures for workplaces to minimise the chance of such spills, and also have a spill management protocol in place to make sure spills are safely cleaned up.

It stipulates that those conducting businesses or undertakings must manage risks associated with the use, handling, generating or storing of hazardous chemicals in a workplace, including identifying foreseeable hazards and eliminating the risk so far as practicable.

One method of stopping and sealing pipelines that is attracting increasing interest and application in Australasia for maintenance and environmental protection applications involves inflatable pipe stoppers that can be rapidly deployed, easily transported and widely applied in urban, remote, temporary and permanent industrial situations.

“Pipelines are a major component of such a risk management strategy and, while many companies are becoming aware of the issues involved, others have yet to understand them fully,” says James Maslin, National Sales Manager for Air Springs Supply, which distributes a broad range of Pronal inflatable stoppers suitable for all types of pipelines including concrete, cast iron, steel, stainless steel and PVC.

“The issues involved in pipeline maintenance and safety are particularly acute during the maintenance season, over Christmas-New Year,  when companies may be handling increased quantities and types of hazardous materials associated with cleaning, vehicle maintenance and plant upkeep, for example.”

The common factor with maintenance, testing and emergency situations is that they need stoppers that can be rapidly and securely deployed to provide primary or secondary safety and environmental security as required by both by Safe Work Australia and State Environmental Protection Agencies.

“Sometimes such stoppers are permanently located in pipelines for instant remote inflation with compressed air or other gas where there is a risk of toxic runoff at different stages of production, or where spillages occur,” says Maslin.

“In other instances they are used to seal off sections of pipe where leaks are occurring, serving the dual role of enabling pressurisation of that section so leaks can be detected, then protecting the men in the pipeline from any product flows while they work to fix the problem.”

One of the early adopters of this technology was Visy Beverage at Smithfield, Sydney, a company committed to strong environmental management which installed a permanent Pronal OFR anti-pollution stopper as a precaution against industrial waste seeping into a stormwater drain passing through its production site.

“What appealed to them was the plug’s their simplicity – they are easy to install and the deflated stopper is designed to allow normal non-polluted effluents or water to pass through the pipe when the stopper is uninflated. It helped too that they were a fraction of the price of the gate valve they we were looking at as an alternative,” said Maslin.

The custom-fabricated plug was especially shaped to provide the security of protection specified by them. With an overall length of 1.64 metres and an effective sealing length of 1300mm, the plug is positioned within the pipe on a central steel axis located by permanent frame.

The plug, which can be inflated in minutes, is used by Visy to prevent accidental spills from trucks or holding tanks that could ultimately pass from the drain into nearby creeks leading to wetlands in parks and heritage areas.

“For further simplicity and reliability, Visy had the inflation feed to the plug permanently linked into their factory pneumatic system via a low pressure regulator. This arrangement, housed within the production site, is very simple to actuate for scheduled testing and for actual emergency conditions,” said Maslin, adding the Visy is committed to environmental management and operating in a sustainable way.

Visy operates its manufacturing sites and business units through an integrated approach by combining environmental excellence with strong social and financial principles into its operations and products.

Another application of the Pronal product involved a national organisation serving both government and private customers which had a storm drain extending through a production plant into surrounding bushland leading to a major waterway.

“We were approached by them for an easily actuated large-diameter stopper to be permanently located in their main storm water drain so that, in the event of a chemical pollution spill, the stopper could be quickly and remotely inflated to prevent any pollutants flowing out directly into the neighbouring heritage stream,” said Maslin.

“The plug had to be able to provide immediate protection in the unlikely event of a spillage, because the customer had a lot of vehicles moving through the plant and lots of drums of materials connected with manufacturing, including liquids, glues, urethanes and so on.”

The storm water pipe inside diameter is 900mm and the stopper is permanently fixed to a central steel axis pole with three supporting feet per end, which bolt to the inside wall of the pipe.

Supplied with the stopper was a surface-mounted complete control box with valving and control equipment. An air or nitrogen cylinder is installed inside the box for remote inflation when activated by pressing a large red easily visible and easily accessible button.     

Actuation of the plug is virtually instantaneous – “After the installation by local plumbers, it was tested and found to be very, very quick. It took only a second or two to provide protection. Then they simply put it back and reset it – it is simplicity itself. These are very rugged multi-use technology designed to withstand extended life in a drain and to function effectively every time they are needed.” 

Protected by a polyethylene cover to counteract effluents aggression, the extensive range of OFR stoppers is available in standard cylindrical lengths of 950-2200mm – with ovoid, elliptical and other shapes on request.

OFR stoppers complement Air Springs Supply’s broader range of Pronal pipe stoppers used for maintenance, testing and emergency tasks in applications as diverse as oil and gas delivery, industrial and municipal water and waste water, and pollution prevention in mining, energy and industrial projects where sealing and testing operations need to be conducted not only with complete safety and environmental security, but also with considerable speed, to maintain flows of liquids and gases.

For smaller diameter pipes, down to 1o0mm, Pronal have developed a complementary product called OPAP Pollu-Plug, which in its uninflated state is permanently mounted flat and conforming to the arc of the top half of a pipe.

Once triggered by remote line, it will expand to fill the entire diameter of the pipe.

Ongoing protection against contamination of waterways from spills into water and sewerage lines is provided by Pronal’s OPAP and OFR Pollu-Plug stoppers, which are permanently and unobtrusively fitted in water and sewerage lines ready for instantaneous inflation by remote triggering as soon as an emergency arises in industrial, civil and municipal applications.

Different ranges respond to the needs of particular industries and pressure requirement, with ORJ types being used for pressures up to one bar and OPV types for pressures up to 3 bar. Higher pressure stoppers are also available.

“The stoppers are also highly versatile in uses such as testing air, gas and water pressure, locating leaks, and even allowing the injection of chemicals or dies into a pipeline when facilitating cleaning or locating leaks in designated sections between two stoppers.

"By using the bypass function within the appropriate stopper, chemicals can be introduced then subsequently either diluted for disposal or purged to tanker or reservoir. It’s very quick and clean, which is very important when seeking to eliminate risk as required by statutory authorities.

“It is also very secure. Pronal products are based on more than 40 years of producing specialist pneumatic elastomer designs for demanding applications, including government, military, heavy industrial, emergency service, sub-sea and exploration” said Maslin.

Air Springs Supply itself has more than 30 years specialist national experience in applying pneumatic actuation and isolation technologies.

“The big advantages of the technology also include simplicity, portability and re-use. Maintenance staff don’t need huge amounts of gear on-site and the stoppers themselves are easy to transport around plants to remote locations, where they can be used, moved on, and used again and again. They are an ideal method by which to achieve compliance with statutory requirements in a cost-effective and efficient manner.”