Alternativní postup optimalizace deskových výměníků tepla

Alternative Approach in Optimization of Plate Type Heat Exchangers

journal article - other

en

Plate type heat exchangers are widely used in process industries for gas/gas applications. Typically, these exchangers proved to be very efficient especially as air preheaters in process furnaces or as equipment of units for environmental protection (e.g. in units for thermal disposal of wastes). From economic reasons of these industries there is a need for a new optimization approach for plate type heat exchanger design and operation. The objective function is of achieving minimum total annual cost of heat exchangers. Pressure drop and heat transfer are interdependent and both of them strongly influence capital and operating costs of any heat transfer system. During the designing a heat exchanger it is necessary to determine optimum dimensions of apparatus which is connected with given conditions of the equipment operation. The goal is to obtain the most economically optimum design. An economic assessment allows a comparable estimation of various alternatives. The total annual cost consisting of fixed and variable costs of heat exchanger were selected as a criterion that summarizes different factors of influence into one objective function. Major cost components of a heat exchange system are as follows: capital, operating and maintenance costs of air and flue gas fans and capital and maintenance costs of the plate type heat exchanger. Application of developed optimization approach is demonstrated through practical industrial examples.

Využití spalin odcházejících z konvekčních sekcí pece k dalším účelům přispívá ke zvýšení účinnosti pece a snižování spotřeby paliva. Pokud se teplo z odcházejících spalin využije k předehřevu spalovacího vzduchu, lze dosáhnout podstatného snížení spotřeby paliva v peci. Dobře navržený předehřívač vzduchu může redukovat spotřebu paliva pece o více než 10%. Nezanedbatelným přínosem je rovněž zvýšení účinnosti pece. Z těchto důvodů se požaduje v petrochemických a chemických provozech efektivní využívání předehřívačů vzduchu. Navíc v souvislosti s rostoucími cenami energie a nutností řešit ekologické problémy spojené se znečišťováním ovzduší dostávají se tato zařízení stále více do popředí zájmu projektantů i provozovatelů procesních zařízení. Nejedná se pak pouze o pece, ale i o principiálně podobně pracující zařízení jako jsou kotle a jednotky pro termickou likvidaci odpadů. Optimální návrh deskového předehřívače vzduchu je předmětem příspěvku.

Plate type heat exchangers are widely used in process industries for gas/gas applications. Typically, these exchangers proved to be very efficient especially as air preheaters in process furnaces or as equipment of units for environmental protection (e.g. in units for thermal disposal of wastes). From economic reasons of these industries there is a need for a new optimization approach for plate type heat exchanger design and operation. The objective function is of achieving minimum total annual cost of heat exchangers. Pressure drop and heat transfer are interdependent and both of them strongly influence capital and operating costs of any heat transfer system. During the designing a heat exchanger it is necessary to determine optimum dimensions of apparatus which is connected with given conditions of the equipment operation. The goal is to obtain the most economically optimum design. An economic assessment allows a comparable estimation of various alternatives. The total annual cost consisting of fixed and variable costs of heat exchanger were selected as a criterion that summarizes different factors of influence into one objective function. Major cost components of a heat exchange system are as follows: capital, operating and maintenance costs of air and flue gas fans and capital and maintenance costs of the plate type heat exchanger. Application of developed optimization approach is demonstrated through practical industrial examples.

Plate heat exchanger, optimization

2004

01.01.2004

0145-7632

25

5

6–15

10