Project Description

Nyrstar Zinc Smelter

During 2005 & 2007 the Nyrstar Hobart Smelter conducted statutory maintenance on their fluid bed roasters (No. 5 & 6).

Due to the age of both roasters, concerns existed about the stability of the refractory brick lined walls and domed roofs of the vessels, particularly in their cold condition.

The fact that personnel had to perform maintenance tasks directly under the potentially unstable refractory  necessitated innovative engineering to alleviate risks to acceptable levels.

JMG were involved with the risk assessment and structural engineering components of the maintenance inspections and provided onsite structural design inputs.

Key issues


Risks involved major and minor collapse scenarios.

Safety of personnel

Safety measures during inspections included using a safety cage and an inflated “balloon” (pictured) to protect against vertical wall instability.

Complex structural behaviour

Complex structural behaviour required finite element analysis (by Finite Elements).

For more information about JMG’s structural engineering services, contact Grant Atherton on (03) 6231 2555 or email

For the project sheet on this project, click here.