Australian Mining Services International – a privately owned company based in Singleton, NSW -– has won the substantial contract utilising the technologies and experience of coal seam gas specialists Valley Longwall Drilling, Mitchell Drilling and GeoGAS.

This is the first time these Australian companies will be working on the one project simultaneously – providing a gas drilling and pre-drainage solution to Shenhua Ningxia’s Baijigou coal mine in China’s Ningxia Province.

Shenhua Ningxia will extract its 20m coal seam using multiple 3m passes. The semi-anthracite coal will be extracted from two longwall blocks, measuring 1.5km and 1.7km long and 220m wide.

Previously Shenhua Ningxia had used longwall top coal caving to extract the seam, taking it in 2 x 10m passes. The new multiple pass method will now be used where the floor is meshed on the first pass, which then becomes a roof on the second and subsequent passes.

Shenhua Ningxia currently only has the capability to drill about 150m ahead of mining, while the Australian companies enlisted in the project can drill up to about 1km.

Gas drainage ahead of mining is essential in this seam which measures 11-plus cubic metres per ton of gas, slow desorption, and short lead time, calling for close spacing of drillholes.

The project will include 44,000m of surface-to-inseam drilling. Mitchell Drilling will use its Dymaxion drilling process, while Valley Longwall will simultaneously undertake underground in-seam drilling. The gas testing, analysis and modelling has been completed over the past 12 months by GeoGAS, working in parallel with Xian Institute of China.

Mitchell Drilling’s innovative Dymaxion process performs where a vertical borehole is intersected by a lateral hole from the surface. This lateral hole is drilled down through the strata and is gradually curved to intersect and run along the coal seam for a distance of 1000m. The pumps are installed in the vertical wells and once the water is drawn down, the gas follows.

The Dymaxion technology is currently used for their drilling enterprises both in Australia and India with over 250 holes drilled to date. This project will be the company’s first foray into China, working under an alliance agreement with AMSI to pursue the opportunities in the coal mine methane business.

Mitchell Drilling has created a joint venture company with a Canadian firm, PACE, and has established a Chinese joint venture company – Mitchell Guizhou Drilling.

The undergound in-seam drilling will be undertaken by Beijing-based Valley Longwall Mining Equipment (Beijing) Co. This company has been set up in China to assemble and manufacture drilling systems and underground diesel equipment for the Chinese coal industry and is a subsidiary of the Valley Longwall International Group of Companies.

This company is no stranger to China and is starting to ramp up sales of its specialised underground drilling systems which are being sold through its China agents – Wadam Industries.

This project gives Valley Longwall chief Chris Freer the opportunity to undertake a demonstration drilling project to showcase the company’s equipment and expertise which has been gained from over two decades of drilling in Australia, China, the US, South Africa and Mexico.

Initiating the project, and now acting as project managers, AMSI directors Peter Eason and Zongbo Zhou have been working in China for more than two years and after forming a joint venture company, CAMDA, with the National Research Institute attached to the State Administration of Coal Mine Safety, have been steadily increasing their foothold in this challenging marketplace.

The project has been nominated as one of six Special Safety Projects for 2007 by the State Administration of Coal Mine Safety, and seeks to demonstrate the process and effectiveness of pre-drainage of mine gases well in advance of the mining process.

The added value of this technology is the ability to harness what is a significant energy source in its own right. The utilisation of the gas to drive internal combustion engines to generate electricity will help reduce greenhouse gas emission.

The Chinese mining industry is set to absorb the gas drilling capabilities of Australia, with the Chinese Central Government legislating to insist on improved gas drainage performance in an effort to reduce the number of fatalities and improve productivity.

The first drilling crew will arrive onsite and begin drainage during the second week of April, with a second crew arriving a few weeks later. The project will be finished by the end of the year.