Devro, one of the world’s leading suppliers of collagen casings for food and meat products, is a major employer in Bathurst and a significant exporter.

A key processing agent used at its Bathurst plant is anhydrous ammonia, which is stored in an outdoor bullet tank. The ammonia is consumed 24/7, 360 days a year. Two factors affect the continuous supply of ammonia:

• The four yearly pressure vessel inspection; and
• Cold weather.

Devro employed CNF to:

• Plan and oversee the four-yearly pressure vessel inspection and overhaul of the 20kL anhydrous ammonia storage tank.
• Provide site supervision during the inspection and overhaul.
• Prepare the tank hazardous area diagram.

CNF’s expertise enabled Devro’s engineering team to focus on in-plant shutdown works associated with the production equipment, happening at the same time as the internal tank inspection.

For cold weather operation, CNF graphed hourly temperatures versus plant supply pressure to provide a predictor of when ammonia gas supply would be limited. Devro installed electrically heated blankets around the standby tanks. To enable this to happen, CNF prepared a hazardous area diagram for the tank and fittings so the heater blankets could be placed safely.