Design optimization of ethylene glycol interwall heat exchange wellhead antifreeze system in Yindonggou Coal Mine

Abstract

A method of extracting exhaust waste heat and heating inlet wellhead by glycol wall heat exchange technology is proposed. Calculation and system design of exhaust air waste heat based on heat balance theory, combined with the actual case of Ningxia Yindonggou Coal Mine project, the Threlkeld enthalpy difference method was used to develop an analytical model for single tube heat transfer under wet conditions and to optimize the operating conditions. The results show that the glycol inter-wall heat transfer technology can extract the heat from the mine return air and meet the heat load required to prevent freezing at the wellhead. The system operates stably when the inlet temperature of the heat transfer medium in the tube is -2 ℃ and the flow rate is 1.49 m/s to 2.76 m/s. When the outdoor temperature is below -15 ℃, the wellhead temperature can still reach above 5 ℃.

Keywords

• mine return air
• glycol heat exchanger
• wellhead antifreeze
• operational optimization
• numerical simulation