Heat transfer to a horizontal tube in the freeboard region of a flu-idized bed has been investigated. The freeboard region can be divided into three different zones for which different heat transfer correlations should be used. By introducing the dimensionless height number X

the heat transfer coefficients can be calculated by use of the correlations in bed for the first zone (X<0.1-0.14)

and for the second zone

which is the main part of the freeboard

equation (5) can be used. The heat transfer coefficients in the third zone (X≥1) are actually equal to that calculated by MacAdams correlation for the cross flow of air. Certain major factors which affect heat transfer in the freeboard region were also examined.