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US Coal Sector Realizes the New Norm Exports will help offset further declines in 2 Editorial 4 Leading Developments News 6 U.S. News 8 Worldwide News 10 People 12 Commentary 14 Calendar 40 Operating Ideas 42 Suppliers News 44 Product News 46 Classifieds 48 Legally Speaking In addition to the Annual Forecast, this month, Coal Age offers extended coverage of the longwall mines with its U.S. Longwall Census. On the cover, a longwall shearer cuts coal with water sprays suppressing dust.

The authors point at the criticality of timely reproduction of longwall panels in coal mines toward sustainable and high-rate coal mining based on the utilization potential of modern longwall equipment. A case-study of SUEK-Kuzbass mines shows that there is a need to change approaches to improvement of economic efficiency and competitiveness of coal mining and to shift from the common practice of production cost reduction to productivity enhancement through implementation of high-performance equipment capabilities. Efficiency of road heading in mines of SUEK-Kuzbass is analyzed, and the main causes of long downtime in operation of modern high-performance continuous miners (CM) or continuous bolter miners (CBM) are identified. Recommendations have been developed for improved planning of preparatory works in mines and for introduction of significant action time margin to eliminate downtime when actual drivage performance lags behind the planning data. The action time structure of modern CBM is presented, and recommendations are given on CBM efficiency evaluation as actual action time in cutting road face rocks. The application areas of various modern CBM types are justified. Recommendations are proposed for changing the parameters of longwall panels and to change to multi-entry longwall panels in order to increase efficiency of preparatory works and actual coal production. The authors describe expediency of widespread use of shuttle cars to improve efficiency of haulage of rocks and materials. The organizational and technological principles of the efficiency increase in preparatory works in coal mines are substantiated.

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The analysis of the experience of methane emission control at the V. D. Yalevsky mine (Kuznetsk coal basin, Russia) during the series of shallow gassy coal seams mining with the high productive longwall was performed. The analysis of the efficiency of gob degassing by the vertical wells and isolated methane removal by gas-suction fans is performed. The efficiency of reducing the distance between ventilation crosscuts between entries is shown. It is also shown that the problems of providing the longwall high productivity in conditions of increasing the natural gas content in the coal seams are associated with gas emission from the extracted coal seam and the lack of effective methods for its early and preliminary degassing. Recommendations for using advanced mining of close-up coal seams as an effective method of degassing of rock mass within the zone of influence of undermining and overmining are given.