Method for modeling and monitoring fouling

摘要

Method for modeling the amount of fouling in a heat exchanger (E) comprising at least a housing (S) and at least one tube (T) disposed in said housing (S) to provide heat exchange between fluids at different temperatures passing through said housing (S) and tube (T), respectively, comprising the steps of: - assigning a temperature difference of input and output for each of the fluids passing through the tube (T) and the housing (S) (100); - calculating an outlet temperature iteratively for each fluid using temperature differences assigned and measured input temperature fluid (101); - determine an outlet temperature for each wash fluid equating temperature iteratively calculated output (102); - calculate an average temperature value for each fluid (103); - calculating a transfer coefficient iterative clean heat for the heat exchanger (E), using the physical properties calculated under average temperatures of the tube (T) and the housing (S) (104); - calculate a logarithmic mean temperature difference, using inlet temperatures and temperatures iterative fluid outlet (105); - update temperatures iterative outlet for each fluid, solving equations energy tube (T) of the housing (S) and the heat exchanger (E), using the transfer coefficient clean heat iterative calculated difference log mean temperature calculated, the physical parameters of the heat exchanger (E), the physical parameters of the tube (T) and the housing (S), and inlet temperatures of the fluid (106); - compare output temperatures Iterative updated with outlet temperatures provided (107); - returning to the step of determining a temperature of expected output for each fluid (102) when the difference between the temperature of updated iteratively output and temperature expected output for at least one of the fluids is above a predefined value ; - calculate instantaneous values ​​for the heat exchanger (E), using temperatures iterative output updated when the difference between the temperature of updated iteratively output and the outlet temperature for each wash fluid is below said predefined threshold value ( 108); and - calculating the amount of fouling in the heat exchanger (E), using the calculated instantaneous values ​​and iterative transfer coefficient clean heat calculated (109).