Exploration of ammonia resorption cycle for power generation by using novel composite sorbent

Expanded natural graphite and carbon coated nickel are selected as the additives in the development of novel composite sorbent. Improved thermo-physical properties of composite strontium chloride result in a faster sorption reaction rate than that without using carbon coated metal. A case study of ammonia-based resorption power generation cycle with two identical reactors is analyzed in terms of sorption characteristics of composite sorbents. Power could be generated in both half cycles, which greatly enhances working versatility and thermal efficiency. It is indicated that additive of carbon coated nickel has a positive influence on performance of resorption power generation cycles. Energy and exergy efficiency of basic resorption cycle range from 0.072 to 0.116 and from 0.402 to 0.737, respectively. Basis resorption cycle for power generation is also compared with improved resorption cycle by using different composite sorbents. Increment between improved and basic resorption cycle by using the sorbent without carbon coated nickel is larger than that using that with carbon coated nickel. Energy density by using novel composite sorbent is improved by up to 20% based on mass and volume of sorption reactor. Through reheating process, performance of basic resorption cycle is further improved by 3-5 times.