Crinum

The Crinum underground coal mine in Queensland is located some 60 kilometres east of Emerald, near the small mining town of Tieri. It is regarded as being a new generation coal mine having first produced longwall coal there in 1997. It was developed for mine owners BHP Billiton and Mitsubishi, as a replacement source of coal for the ailing nearby Gregory open cut mine that was finally closed in 2012.

The Mining of Metallurgical Coal at the Crinum Underground Mine

The Crinum mine that is able to produce 4.25 million tonne of metallurgical coal a year, employs approximately 200 people either as direct employees or contractors. The mine is accessed by means of a 85 metre deep, by six metre in diameter, ventilation shaft and two declines that were constructed by Thiess Contractors. The coal mined at the Crinum mine is taken by conveyor to the Gregory preparation plant where it undergoes processing into three products:

• Thermal coal
• Weak coking coal
• Hard coking coal

State of the Art Development at the Mine Face

Three Joy continuous miners, that are remote controlled, are used to develop the main in-seam infrastructure of the Crinum underground mine along with mobile bootends that are crawler mounted. These advance the panel conveyor behind the miner and make for continuous development. The roof and rib bolting methods used at the Crinum mine were blamed at one stage for miners suffering a number of strain injuries due to what was identified as an inefficient bolting procedure during development operations. This was eventually overcome by the team implementing a concept of placing electro-hydraulic controls on the continuous miner bolting apparatus that improved maintenance and operational work. These changes have given the operators more room to work in and an improved quality of roof and rib bolting.

Coal taken from the seam is crushed to a diameter of approximately 200mm or less at the stage loader. It is then transported by conveyor belt at a rate of 3,000 tonnes an hour and a speed of almost five metres a second, to the surface. The 1,800 kW installed power driving the decline conveyor is one of the highest in any Australian mine.

Water Inflows Monitored 24 Hours a day

Water is a continuous problem at the Crinum underground mine although its management has proved to be successful. To keep the water under control the company has installed three 80 litres a second portable pumps and five 60 litres a second submersible water pumps. These are operated automatically by a computer system that monitors any excess water flowing into the mine.

Workers Safety is a High Priority

All miners working underground at the Crinum mine are given their own oxygen self-rescuers as well as each individual miner being able to be contacted personally in case of emergency via a receiver hooked up to the battery in his or her helmet. There is also a safety guard in place to prevent any worker falling onto a conveyor belt. Any blockages beneath the stockpile feeder are able to be removed by remote control. The mine was awarded the Queensland Mining Industry Health and Safety Innovations Award in 2009 for its work in this area.