Operation Diagnosis And Simulation Optimization Of A Plant Cooling Room In Jiangmen City

With the promotion of the "double carbon" concept and the acceleration of industrialization,people are increasingly concerned about the energy saving in existing industrial plants.The industrial plant air conditioning system has a large load,cooling time plant and large changes,so the air conditioning energy consumption should not be underestimated.In this paper,by collecting data,reviewing literature and using the cloud monitoring platform of a refrigeration plant room,we obtained and compiled one year’s operational data of a plant refrigeration plant room,and corrected the problem data by using linear regression method.The time-by-time variation characteristics of the chiller performance coefficient,chilled water delivery coefficient,cooling water delivery coefficient and other parameters were analyzed.The distribution of annual cooling load rate,energy consumption distribution and energy efficiency were studied.The results of the study show that: the time when the chiller unit supply load ratio is 50% or below accounts for more than 80% of the annual operation time;when the supply load ratio drops below 50%,the chiller room is in the operation condition of "large flow rate and small temperature difference";in the annual energy consumption distribution of the chiller room,the energy consumption of the chiller unit accounts for 58.45%,the energy consumption of the transmission and distribution system accounts for 35.04%.This refrigeration room has the characteristics of long operation time and low cooling load factor,and deviates from the energy-saving design condition,which indicates that there is some room for energy-saving optimization in this refrigeration room.The chiller performance model and energy consumption model were constructed using the operation data,and the performance coefficient of the chiller at the cooling load rate interval of40% to 80% was analyzed to be higher than that at 100% cooling load.The mathematical model of variable frequency water pump was obtained by data fitting,and the operation law of the pump with the lower limit of energy-saving variable frequency was obtained.According to the cooling tower thermal mass exchange principle,the relationship equation between air-to-water mass ratio and thermal mass exchange coefficient is calculated and obtained.The energy-saving operation mode of the refrigeration room was analyzed by TRNSYS simulation software,and the energy-saving of the variable flow operation mode of the refrigeration room was analyzed,which can reduce the energy consumption by 9.59% compared with the fixed flow operation mode.Simulation of the operation strategy of the chilled water side of the refrigeration room with the chilled water supply temperature was carried out,and the energy consumption could be reduced by 2.93%.Simulation of the cooling water side of the refrigeration room with a variable temperature difference and variable flow rate operation strategy resulted in an energy consumption reduction of 2.62%.This research can provide reference for energy-saving diagnosis and optimization of refrigeration rooms,and has certain feasibility and practicality.