Hyperlast Ltd

Groundbreaking transportation method for powder polymer developed by Haden Freeman

Hyperlast Ltd, part of the British Vita Group, is a leading international systems house combining chemical and engineering expertise to create innovative polyurethane elastomers for practical industrial applications. Polyurethanes are extremely versatile materials. Toughness resilience, wear resilience, flexibility, and tolerance of harsh and aggressive environments make them ideal for a huge range of applications from protecting sub-sea pipelines to electrical insulation and furniture moldings.

The Challenge
Part of the production process of the insulating material involves transferring an unexpanded powder polymer chemical from large bags to an expander. Haden Freeman Ltd (HFL) was briefed to develop a more efficient transportation method for the polymer, to allow continuous production and improve safety, while driving up the company’s output.

Transporting the powder polymer requires extreme care as each sphere contains the highly flammable substance isobutene as a blowing agent, as well as small concentrations of numerous toxic chemicals, including acrylonitrile. Fire hazards at the plant are therefore extremely high and any lack of containment could cause a dust explosion, thereby damaging the surrounding countryside.

Due to the tiny particle size of Expancel, leakage could have safety implications for plant personnel, who could potentially inhale the dust. To maintain a safe working environment, Hyperlast has been limited to producing Expancel in small batteries, therefore restricting the speed at which the insulating material can be produced.

The Solution
To overcome this restriction, HFL developed a quicker and safer way of handling and transporting the material. The previous method of transferring the powder polymer was to ‘pump’ it using diaphragm pumps, where a mixture of solids and air were pulled through a pumping mechanism. However, HFL developed a system where the air in the pipes was replaced with nitrogen to minimise the risk of an explosive atmosphere forming in the system.

Personnel safety in the plant was improved with a special discharge mechanism, which allows Expancel to be discharged at a constant feed into the expander, removing the need for a manned operation. An extraction system was also developed to reduce the dust and vapor concentration levels in the working environment and to keep levels below the lower explosive limits.

A nitrogen blanketing system was also fitted to the intermediate silos where the Expancel was transferred to. This ensured that the oxygen concentration levels in the silos remained at below 5%, to maintain a non-explosive atmosphere. An oxygen analyser was put in place to control these levels and the risk of a flammable atmosphere developing was further reduced by earth bonding pipework, flexible hoses and equipment to minimise the risk of a static spark.

The project ran from September 2005 and completed in February 2006, on time and to budget.

Haden Freeman provided engineering design, project management and construction management as well as supervising contractors and managing budget. A team of seven worked on the project from Haden Freeman, which has had an informal alliance agreement with Hyperlast in place since 2005.

Ian Dunkley from Haden Freeman said: “We have a consistent and successful track record of carrying out this kind of work and this is a great example of how we can develop an innovative solution that can dramatically improve the way a company operates.”