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Coal bed methane (CBM) reservoir production is controlled by a large set of parameters: geology, tectonics, reservoir, completion and operation. Its simulation process is complicated, relative information is difficult to be obtained, so it is necessary to analyze accurately coal bed gas potential production capacity by adopting other mathematics methods in case of incomplete information. Regarding this problem, a new type-2 fuzzy logic system (T2FLS) method to predict CBM production capacity is proposed in this paper. Methods analyze and assess input parameters of T2FLS by integrating qualitative analysis method and quantitative assessment method (Fuzzy cluster analysis and grey correlation degree analysis). Output parameters include cumulative average gas production, peak gas rate and time to achieve a peak rate. T2FLS production forecast method is applied to CBM wells of Hancheng mine and verification results show that such prediction results are highly consistent with the variation of the CBM well production. The proposed method required less data. The comparison of this method with the existed method (ANN, T1FLS) shows that the proposed method has notable advantage in generalization, stability and consistency.

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Surface mining of oil sands is generally limited to areas where the overburden thickness is less than ~75 m. Oil sands consist of a mixture of coarse sands, fine mineral solids, clays, formation water, and bitumen. Usually the orebody varies from 20 to 90 m in thickness, and the oil sand formation deposit is not homogeneous as it is intermingled with clays lenses (interburden). Bitumen content has been traditionally used as an indicator of ore processability. In fact, ores with a bitumen content of below 7% are considered uneconomical for processing. In this study, four types of ores were selected to evaluate the effect of adding two types of interburden with high clay contents on their ore processability. Ore processability was tested using the batch extraction unit. It was found that the interburden dilution does not always detrimentally affect the recovery. Depending on the ore grade, interburden dilution may boost the recovery for coarse grained ores, and depress the recovery for average and low grade ores. Current operational use of a maximum allowable fraction of interburden blended into oil sand feed may be overly simplistic. The results suggest that dilution to a maximum fines content of the blend is required rather than to a maximum fraction of interburden. Interburden effect on tailings settling behavior was also studied.