Combined heat and water system for long-distance heat transportation

Abstract

Chinese district heating systems are transforming to clean heating systems. The excess heat in CHP and industrial plants are expected to play a dominant role in the transformation considering their enormous heating potential. As excess heat sources usually locate distant from heat demand center, efficient transportation technologies are required. In this paper, combine heat and water (CHW) system was proposed for long-distance heat transportation, using water in water supply system as heat carrier. The CHW system gives heat a free ride to urban area, no needing return water pipeline; thus, it can sharply reduce the costs of transportation. According to investigation, the application prospect of CHW was found in Northern China. A CHW system scheme combing seawater desalination system and excess heat heating system was introduced. Furthermore, through a case study in Xiongan new area, the energy efficiency and economic cost were analyzed. The proposed CHW system can provide 1500 MW heating capacity and 100 million m3 annual water supply quantity. The efficiency of heating with the CHW system is equivalent to a heat pump with COP at 6.74, even the transportation distance is over 200 km. The CHW system has significant advantages in long-distance heat transportation.