Urban sewage is a renewable energy source in the fields of heating and air conditioning engineering, and urban sewage source heat pump system plays an important role on energy-saving and environmental protection. According to the differences of the sewage emission coefficient and heat load of the building, it is not able to satisfy the user heating demand only on the limited temperature difference sensible heat on many situations, especially for the sewage rate of flow in small trunk canals. Therefore, a new heat system named urban sewage source heat pump system with freezing latent heat collection is proposed, in which the freezing latent heat is used as the heating source of the heat pump system at peak heat load in winter as well as the temperature difference sensible heat. According to the status, the system form is brought out and the operation modes of this heat pump system are stated, then the characteristics of the design and operating parameters are discussed.

Put forward an application of ultrasonic cavitation technology of the sewage source heat pump system to solve the problem of controlling pollution and emphatically discusses the principle of acoustic cavitation and the effect, to conduct a feasibility analysis of Anti-fouling in sewage source heat pump sewage side. Through analysis principle of ultrasonic cavitation and heat transfer enhancement for carrying the experiment, study the pattern of scaling in heat exchange tube for different velocity and viscosity, effect in flow rate on the ultrasonic cleaning wastewater, Effect in ultrasonic treatment time on the descaling result. Obtain that it can enhancement transfer for 48%.

sewage heat exchanger is important to collect heat energy in sewage source heat pump system. Heat transfer enhancement effect is not obvious while the chemical methods and manual cleaning is applying to remove the heat exchangers fouling in the long-term operation. Here sets an ultrasonic incrustation removal physical model in heat exchanger structure to antiscaling and descaling simultaneously. The acoustic cavitation technology can be used in sewage source heat pump systems for the experimental results and decontamination rate reaches 50%.