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The 6th coal seam floor of Tangjiahui Coal Mine is seriously threatened by Ordovician karst water. It is the mine with the deepest mining depth and the highest water pressure in Zhungeer Coal Field. In order to eliminate the threat of water damage from Ordovician floor, the ground area treatment test project was carried out on the 61207 working face of Tangjiahui Mine. The test results show that there are many leakage and return phenomena during the directional drilling process, the grout is large in the grouting project, the efficiency of drilling and grouting is low, and the 61207 working face adopts the ground area treatment method to prevent and control the floor Ordovician water damage. The construction period is long, and it is difficult to meet the needs of continuous cost control of the face production. Through comprehensive comparative analysis, it is advisable to adopt the technical route of water prevention and control, which is the combination of “bottom exploration and reinforcement by directional drilling inside working face” and “treatment of fault zone by directional drilling outside working face”.

This paper investigates global optimization of the detailed design of intensified shell and tube heat exchangers using two tube inserts: twisted tape and coiled wire. Three objectives, including heat exchanger area, total annualized cost, and environmental impact, are respectively minimized. All the design variables are considered as the ones that have discrete values based on their physical nature or manufacturing standards. We present, for the first time, a tailored global optimization approach for the design of intensified shell and tube heat exchanger: Set trimming procedure. We compare the computational performance of our set trimming procedure, exhaustive enumeration, and commercial solvers. The proposed three objectives have certain competitive relationships and multi‐objective optimization is performed to analyze the conflicts among them. Two literature examples are tested for illustration purposes. The solution results indicate that the intensified heat exchanger designed using tube inserts compares well to the regular heat exchanger using plain tube. Compared with commercial solvers, set trimming procedure runs fast and can converge to global optimum without initial value. The pareto‐optimal solutions of multi‐objective optimization provide holistic trade‐offs between different objectives, hence helping the process designer make proper decisions for the design of intensified shell and tube heat exchangers. [ABSTRACT FROM AUTHOR]