Slurry fired heater cold-flow modelling

Technical Report · Fri Jul 01 00:00:00 EDT 1983

DOI:https://doi.org/10.2172/6933572· OSTI ID:6933572

Moujaes, S. F.

This report summarizes the experimental and theoretical work leading to the scale-up of the SRC-I Demonstration Plant slurry fired heater. The scale-up involved a theoretical model using empirical relations in the derivation, and employed variables such as flow conditions, liquid viscosity, and slug frequency. Such variables have been shown to affect the heat transfer characteristics ofthe system. The model assumes that, if all other variables remain constant, the heat transfer coefficient can be scaled up proportional to D/sup -2/3/ (D = inside diameter of the fired heater tube). All flow conditions, liquid viscosities, and pipe inclinations relevant to the demonstration plant have indicated a slug flow regime in the slurry fired heater. The annular and stratified flow regimes should be avoided to minimize the potential for excessive pipe erosion and to decrease temperature gradients along the pipe cross section leading to coking and thermal stresses, respectively. Cold-flow studies in 3- and 6.75-in.-inside-diameter (ID) pipes were conducted to determine the effect of scale-up on flow regime, slug frequency, and slug dimensions. The developed model assumes that conduction heat transfer occurs through the liquid film surrounding the gas slug and laminar convective heat transfer to the liquid slug. A weighted average of these two heat transfer mechanisms gives a value for the average pipe heat transfer coefficient. The cold-flow work showed a decrease in the observed slug frequency between the 3- and 6.75-ID pipes. Data on the ratio of gas to liquid slug length in the 6.75-in. pipe are not yet complete, but are expected to yield generally lower values than those obtained in the 3-in. pipe; this will probably affect the scale-up to demonstration plant conditions. 5 references, 15 figures, 7 tables.

• Research Organization: International Coal Refining Co., Allentown, PA (USA)
• DOE Contract Number: AC05-78OR03054
• OSTI ID: 6933572
• Report Number(s): DOE/OR/03054-32; ON: DE84013791
• Resource Relation: Other Information: Portions are illegible in microfiche products. Original copy available until stock is exhausted
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
CHEMICAL REACTORS
FUNCTIONAL MODELS
HEAT TRANSFER
MULTIPHASE FLOW
SCALING LAWS
SRC PROCESS
CHEMICAL REACTIONS
COAL LIQUEFACTION
COAL LIQUIDS
COKING
FLUID MECHANICS
FUEL SLURRIES
FUELS
HEATERS
PRESSURE DROP
RHEOLOGY
CARBONIZATION
DECOMPOSITION
DISPERSIONS
ENERGY TRANSFER
FLUID FLOW
FLUIDS
LIQUEFACTION
LIQUIDS
MECHANICS
MIXTURES
SLURRIES
SUSPENSIONS
THERMOCHEMICAL PROCESSES
010405* - Coal
Lignite
& Peat- Hydrogenation & Liquefaction