Bivalent Carbon Dioxide Heat Pump for Heating of Multi-Story Buildings. Part II

The use of heat pumps is one of the components of the energy transition. The article considers a scheme of a combined heat and power plant with a centralized heat supply system, in which the thermal regime of a number of buildings is ensured by installing heat pumps in them that receive low-potential heat from the return network water and from the outside air. The aim of the work is to create a scheme of a bivalent heat pump (BHP) that uses both the heat of the return network water and the heat of the outside air as sources of low-potential heat (LPH) in the normal operating mode and in an emergency mode, when there is a refusal to supply return network water. The set objective is achieved by solving the following problems: constructing BHP thermodynamic cycles and analyz-ing them, analyzing the operation of the scheme under random disturbances, developing an ACS of the heat pump. The most important results of the work are: a scheme of a heat pump that can func-tion at variable pressures of the evaporator and gas cooler, the introduction of a pre-gas cooler into the BTN circuit, installed before the "coolant-water" gas cooler stage, the control system of which ensures the required temperature of the network water heated by the heat pump of the building. The significance of the obtained results consists in the creation of a BTN circuit, which allows ensuring both qualitative and qualitative-quantitative laws of regulation of the thermal mode of the building in emergency modes caused by the absence of heat supply from the return network water.