Integrated Nitrogen Production and Conversion of Hydrogen to Ammonia

Abstract

A novel integration of N2 production, NH3 synthesis, and power generation is performed to realize an effective H2 conversion system to NH3. The system employs the principles of exergy recovery and process integration to achieve high-energy efficiency. The produced high purity N2 from N2 production module is reacted with H2 in NH3 synthesis module to be converted to NH3. In addition, the produced O2-rich gas is utilized as the effective oxidant in power generation module. A single column is adopted in N2 production module, and the feed is divided into two streams which are fed to the middle and bottom of the column. In N2 production module, two operating parameters of bottom feed and refed stream ratios are evaluated in terms of the consumed energy, N2 purity and O2 molar fraction in O2-rich gas. Compared to previous studies on an N2 production system, the proposed N2 production module can reduce the energy consumption of about 43 % (3.27 MW compared to 5.76 MW to produce 1 tmol-N2 h-1).