Optimum Arrangement of Tube Coil in Radiation Type of Tubular Furnace

conference paper

English

Radiation tubular furnace type is the simplest tubular furnace. Tube coil is placed around wall inside vertical cylindrical radiant (combustion) chamber. Coil can be solved as classical vertical type (i.e. vertical straight tubes connected to elbow) or as spiral type for minimisation of fluid pressure drop. Radiation tubular furnaces are characterised by low thermal efficiency (thus relatively high fuel consumption). On the other hand it is the cheapest equipment for specified duty. Radiation tubular furnace types are designed for large scale of process mainly single-phase applications. Typical applications are for example furnaces for heating liquid of gas fluids to required parameters or so-called regeneration furnaces for heating gases or gas mixtures. Radiation tubular furnaces are used when it is not possible to heat the process fluid to required temperature by other way (steam, process streams etc.). Just very frequent using of this type of tubular furnaces together with above mentioned reasons was initial point to searching the suitable arrangement of tube coil for economic optimum design and operation of this tubular furnace type. Tube coil arrangement dominantly influences thermal-hydraulics characteristics of furnace and its economy. Presented method is based on standard long time used design methods (Lobo-Evans method, Belokon method). It is shown, how these standard global design methods can be (for common-operating conditions) suitable generalised and simplified. It allows (for purpose of optimum design of coil arrangement) to arrange the basic heat transfer equation for radiant chamber. In connection with investment cost relations for individual furnace subsystems (tube coil, burners, lining, etc.) and operating cost relations (fuel consumption, fluid pumping cost) can be obtained final objective function of total cost. This objective function then allows finding the optimum coil arrangement from minimum total cost point of view. Moreover, obtained results allow formulating some general recommendations suitable for furnace designers. Developed method can be used for individual solution of radiation type of tubular furnaces and also for first (preliminary) design stage usually connected with proposal for customer when only basic process and furnace design data are usually known. Developed method can be also used for effective solution of integration of radiation furnaces into processes.

process furnace, optimisation, heat transfer

JEGLA, Z.

2006

1. 8. 2006

Praque, Czech Republic

80-86059-45-6

CHISA 2006 Proceedings, Summaries 4

1

15

15