International Society for Industrial Process Tomography

Two-Phase Flow in 3D CAD Pilot Unit Simulation
and Gamma Ray Tomography Validation

Claudino L. Silva^1*, Vieira E. Bertony², Dantas C. C³, Barbosa E. Santos⁴ and Oliveira M. F. M.⁵

¹Department of Nuclear Energy, Federal University of Pernambuco, Recife, Pernambuco, Brazil

^*E-mail: ldclaudino@hotmail.com

ABSTRACT

Flow structure and solid circulating rate are quantified in a 3D CAD pilot unit by means of a CFD – Computational Fluid Dynamics analysis embedded in the mechanical design environment. Solidworks software provided CAD environment and CFD models. The two-phase flow is simulated in the CAD geometry and fluid dynamic parameters values are compared with gamma ray tomography measurements carried out in a similar hardware pilot plant. Riser has 6.7 m high and 0.10 m in external diameter and return column of same diameter connected by the separation vase on the top. Same dimension of the hard unit with air and catalyst form Fluidized Catalytic Cracking - FCC process circulating under steady state operational conditions as it is required by fluid dynamic model hypothesis. According to developed methodology solid circulating rate in closed-loop is determined and flow distribution in riser follows a core-annulus structure captured by gamma transmission measurements. Pressure profile was compared in both virtual and hard pilot risers and solid concentration distribution shows a fairly good agreement. Prediction of the circulating solid rate in closed-loop is validated by gamma ray transmission measurements. For given operational condition of 0,0116 of air flow and 0,1of solid feed the phases velocity distribution along of riser were by 0,23 to 1,24 , having obtained an average of 0.75 m / s. These results were compared with literature data and a two-phase flow reliable profile is obtained.

Keywords CFD, FCC geometry, two-phase flow simulation, virtual pilot unit.

Industrial Application: Oil and gas.