The Research On Natural Cold Energy In The Refrigeration System Of Dairy Plant In The Winter Of Northern

China is a developing country which has shortage in energy supply. As the domestic economy continuously and rapidly develops, the need for energy is growing rapidly, which increases the stress on domestic natural resources and environment. Therefore, how we can enhance the use ratio of energy and develop new substitute energy becomes urgent issues that the world faces to nowadays. The natural cold resource which is also known as the energy in various forms like winder cold air, ice and snow and the cold water, etc. is an inexhaustible and tremendous resource fortune given by the Nature. To develop and use it scientifically, appropriately and efficiently will be of great significance and far-reaching.Regarding to this practical issue, besides doing certain researches on domestic and foreign literatures and documents, this thesis proposes to combine the natural cold energy in Northeast area winter with refrigeration system for the first time, researching and analyzing on its feasibility and exploring the practical effect and anticipated problems to obtain the relevant statistics to present the reference basis for the application research of the natural cold energy in Northeast area winter and the energy saving of refrigeration system.First, we do some research on the application feasibility of the natural cold energy being used in the dairy products factory refrigeration system. By considering the features of dairy products factory refrigeration system. Proceeding with the energy saving, we do research on the various feasible programs on matching the outdoor cold energy and the energy required in dairy products factory. We compare and analyze the merits and demerits of various programs to set a medium device which can transfer the outdoor changing cold resource into the required constant cold resource to save energy.Second, we research and design the application device of the natural energy in dairy products factory refrigeration system. By taking dairy products factory as the research object and giving research on the principle of dairy products factory refrigeration and natural energy, this thesis is to put the natural cold energy in North into application in the dairy products factory refrigeration system. The main content of this thesis is to design and calculate the medium device which is also called natural cold energy application device between the natural cold energy and dairy products factory refrigeration system. By calculation various outdoor temperatures, selection of materials and pipe diameters and amount of calculation of the coefficient of dairy products factory cold energy heat transfer and the area of heat transfer to design the application device for natural cold to save the energy in dairy products factory. We also do research and imitate the water temperature in application device distribution of natural cold energy to imitate the heat transfer condition that the application device works in various outdoor temperature,Then, we do research on the result of the application of natural cold energy in Northeast in the process of dairy products factory. We measure the temperature each hour for the water supply in the processing refrigerant medium in the device and measure the continuous conditions and changes of temperature of outdoor device and draw the temperature changing curve. We put the imitation statistics and winter applied test statistics into analysis to find the consistency and verify the imitation for the imitation.Last, we show our expectation to the generalization, revision, research of the designed natural cold energy application device. We will find out the difference between the experiment and imitation and do the research and analysis to revise the theory. We also take measures to prevent the refrigerant from being frozen so the natural energy application device which can be used at various outdoor temperature, which verifies the feasibility of the natural cold energy in Northeast area in winter being used in dairy products factory saving energy. We analyze the difference and commonality between the other refrigeration companies and dairy products factory. We can revise the designed natural cold energy application device according to different refrigeration companies’various cold energy and other requirements to put it into other refrigeration companies like high temperature cold storage, medicine manufacturing, foods manufacturing, and any other refrigeration companies who take portable water as their refrigerant. Except respective cold specifications shall be designed by itself, the thesis’s design of the application device can be used. It can be also used in the beer factory, the refrigerant is different from that used in dairy factory. The refrigerant in beer factory is ethylene glycol whose freezing point is at-12.6℃, therefore the natural cold energy application device can be used in a way that water runs inside the pipe and the ventilation runs outside pipe, additional to which, the anti-frozen measures shall be taken. Putting this application device into use in all refrigeration industry contributes to the energy saving in the industry and is far-reaching meaningful to the continuous development in the society.