Simulation and heat exchanger network designs for a novel single-column cryogenic air separation process

doi:10.1016/j.cjche.2018.08.014

Abstract

Abstract: To realize the industrialization of the novel single-column air separation process proposed in previous work, steady-state simulation for four different configurations of the single-column process with ternary (nitrogen, oxygen and argon) is developed. Then, exergy analysis of the single-column processes is also carried out and compared with the conventional double-column air separation process at the same capacity. Furthermore, based on the steady-state simulation of single-column processes, the different heat exchanger networks (HENs) for the main heat exchanger and subcooler in each process are designed. To obtain better performance for this novel process, optimization of process configuration and operation is investigated. The optimal condition and configuration for this process is consisted as:feedstock is divided into two streams and the reflux nitrogen is compressed at the approximate temperature of 301 K. In addition, HEN is optimized to minimize the utilities. HENs without utilities are obtained for the four different configurations of single-column process. Furthermore, capital costs of the HEN for different cases are estimated and compared.

Key words: Cryogenic air separation, Single-column, Exergy, Pinch technology, Heat exchange network

摘要： To realize the industrialization of the novel single-column air separation process proposed in previous work, steady-state simulation for four different configurations of the single-column process with ternary (nitrogen, oxygen and argon) is developed. Then, exergy analysis of the single-column processes is also carried out and compared with the conventional double-column air separation process at the same capacity. Furthermore, based on the steady-state simulation of single-column processes, the different heat exchanger networks (HENs) for the main heat exchanger and subcooler in each process are designed. To obtain better performance for this novel process, optimization of process configuration and operation is investigated. The optimal condition and configuration for this process is consisted as:feedstock is divided into two streams and the reflux nitrogen is compressed at the approximate temperature of 301 K. In addition, HEN is optimized to minimize the utilities. HENs without utilities are obtained for the four different configurations of single-column process. Furthermore, capital costs of the HEN for different cases are estimated and compared.

关键词: Cryogenic air separation, Single-column, Exergy, Pinch technology, Heat exchange network

Quancong Zhang, Zuqian Wu, Zhikai Cao, Qingyin Jiang, Hua Zhou. Simulation and heat exchanger network designs for a novel single-column cryogenic air separation process[J]. Chinese Journal of Chemical Engineering, 2019, 27(7): 1498-1509.

Quancong Zhang, Zuqian Wu, Zhikai Cao, Qingyin Jiang, Hua Zhou. Simulation and heat exchanger network designs for a novel single-column cryogenic air separation process[J]. 中国化学工程学报, 2019, 27(7): 1498-1509.

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