Development And Application Of Trickle Falling Film Type Heat Pump Control System

The concentrated bathroom bath wastewater containing a large amount of energy, it is an energy saving and environmental protection and clean energy supply by using water source heat pump technology to recycle the heat energy. Compare with the conventional domestic hot water system, this mode can save energy about30%to50%.The research work of this thesis is a portion of Beijing Municipal Science and Technology Commission’s topic named "life wastewater energy utilization technology development and demonstration project". The main task of the study is to build a complete demonstration project which recovers the heat from life wastewater. The demonstration project can recycle heat from life wastewater more than3500kwh at full lead operating condition every day. The recycling heat energy is used for heating water to supply students’bath center and International Education Center. The members of the project group research and develop a trickle falling film type heat pump whose maximum output power is higher than400kw. In the proximity of the most adverse conditions, heat pump minimum energy efficiency ratio can reach1:4.5. Heat pump control technology and the comprehensive energy saving technology can reach the domestic advanced level.Based on the above conditions, this paper conducts the following research:First, After site testing and commissioning, this paper proposes a set of new type oil return system which is controlled by PLC and only suitable for the heat pump, with traditional oil return system comparison, the system return oil effect is better; Second, by using Emerson PLC, this paper realizes the compressor parallel driving, Heat pump system for unattended operation, water supply and electronic expansion valve PID control functions, the heat pump system can achieve intelligent control purposes, Timing and constant temperature hot water supply and Electronic expansion valve PID control function; Third, a touch screen man-machine interface is completed in this heat pump system, the staff can operate the pump system. In addition, a remote monitoring system is developed in the industry computer, the staff can complete the remote of the operation of heat pump system; Fourth, the paper records important data for the heat pump system nearly half a year, including water temperature, heat pump power consumption. Through these data, this paper calculates the heat pump unit energy efficiency coefficient, then analyzes the economic benefit of heat pump system.