Abstract
Transient flow of gas and gas-condensate in wells is a problem of industrial interest. Studies
abound in the use of pressure transient models in the analysis of hydrate formation, growth and
deposition in these wells but no study in the use of thermal transient model in the evaluation of
these crystalline solids in gas and gas-condensate in wells. Partial and/or complete well
blockages stem out from the deposition of hydrates and other solids, but hydrate deposition
happens to be the one having the most significant effect in the blockage of these wells leading to
reducing flow capacity or total loss in productivity.
This work therefore aimed at developing and using thermal transient analytical model to locate
hydrates growth and deposition in vertical wells. To accurately do this, the conservation of
material, momentum and energy conservation which were the governing equations was applied
to solve the transient flow of gas and gas-condensate in pipelines with respect to their diameter.
The application of these conservation equations resulted into nonlinear hyperbolic equations,
which were arranged in a canonical form and solved analytically using method of characteristics.
Developed model revealed that hydrate formation or growth and deposition in these fluids well is
a function of fluid and solid mechanics, changes in fluid and surrounding conditions, fluid
composition and flow rate variation. Solutions of the resulting equations include consideration
of flow rate, shear stress and compressibility factor to hydrate growth along pipeline. The results
were compared with the field and literature data and a sensitivity analysis was carried out to
determine the effects of these varied parameters in the formation, growth and deposition of
hydrates in gas and gas-condensate wells.