Abstract：The residual energy and heat of basic oxygen furnace (BOF) mainly contains sensible heat and latent heat (chemistry energy) of basic oxygen furnace gas (BOFG), and sensible heat of BOF slag. It is very important to recover reasonably the residual energy and heat of BOF for achieving ‘minus-energy’ steelmaking. According to production data of some steel plants, a finite time thermodynamics (FTT) model of an open gas turbine CCHP (combine cooling, heating and power) plant driven by residual energy and heat of BOF is established. By taking total useful energy rate and first law efficiency as objectives, when there is no constraint for gas mass flow rate and total size of the plant, the relative pressure drop of compressor inlet and pressure ratio are optimized, and the maximum total useful energy rate and the corresponded gas mass flow rate are obtained. In the case of constraints for gas mass flow rate and total size, the relative pressure drop of compressor inlet is optimized and the optimal efficiency is obtained, also the components’ flow area distributions of the plant are optimized. The effects of parameters (such as sensible heat utilization of the gas, gas release rate, cycle temperature ratio, generator working fluid temperature and thermal consumer-side temperature, et al.) on the optimal performances of the plant are analyzed.
2014, Vol. 24 
