Marithan® polyurethane (PUR), Fenoflex ® and Marisil E are two component products used to consolidate and confine highly fractured strata. PUR is a versatile product that can be used in a wide array of applications from binding together fractured strata to sealing water inflows in strata and around ventilation seals and bulkheads. Fenoflex ® is a phenolic resin product with similar use to PUR but with reduced health risks. Marisil E supplements the existing injection products and is our first silicon resin.
HISTORY AND PROVEN CAPABILITY
Polyurethane (PUR) was first used in Europe in the 1960’s. The technology was developed mainly in Germany and France where underground coal mining was conducted in more challenging deeper coal seams.
In 1992 WM was granted the exclusive rights in Australia for the Willich PUR and Silicate Resin System. The first application of PUR by WM was in 1993 at BHP’s Teralba mine. Then in October 1999, WM obtained sole distributorship of the Weber range of PUR products. This versatile product now has widespread use across the Australian underground coal industry. Fenoflex ® was introduced by WM in 2005 to offer a phenolic resin strata binding product to industry.
WM achieved a 25 year milestone for PUR services to the Australian coal industry in 2018.
Marithan ® polyurethane (PUR), Fenoflex and Marisil E products are injected into the strata in limited quantities as specified by licence conditions and are therefore not suitable to be used as bulk cavity fillers. For PUR temperatures can reach up to 150oC whilst curing so a 200kg maximum hole quantity limit is applied for coal strata. For Fenoflex this limit is greater at 600kg. For Marisil E this limit is 400kg.
Holes are drilled into the strata using an injection pattern specified by the mine that is suited to the degree of ground destabilisation. A standard pattern would involve an array of 4-10m long 43-55mm diameter holes drilled into the rib and angled up into the roof. Expansion packers are fitted to either fibre glass or steel hollow injection bolts. Long holes of 10-20m or multi-injection chemical systems are also available.
Chemicals are delivered to the work site in bulk QDS pods and mixed at the work site. Marithan ® polyurethane (PUR), Fenoflex ® and Marisil E are applied using a metering pump and a mixing gun. Separate delivery hoses are used for resin and catalyst products.
The undertaking of a polymeric process is a licensed activity in NSW coal mines. WM holds a current NSW licence for the application of Marithan ® polyurethane (PUR), Fenoflex ® and Marisil E. These licences specify minimum standards for the safe application of these products including exclusion zones, workplace and health monitoring requirements.
Marithan ® polyurethane (PUR), Fenoflex ® and Marisil E operations in QLD currently follow the same licence requirements as in NSW until a recognised standard is developed and implemented.
PROCEDURES AND TRAINING
WM is a Quality Endorsed Company and our management system has been developed in accordance with AS/NZS ISO 9001:2015.
WM has developed comprehensive procedures and industry leading competency-based training for this licenced activity. WM operators undertake all pumping and application activities whilst chemical handling and transport activities can be under taken by either WM operators or mine operators that are chemical awareness trained and assessed.
MONITORING AND TESTING
WM operates to an OHS Monitoring Plan that is reviewed annually to ensure workplace and health monitoring is effective and consistent with the latest technology, standards and methods available.