ZHANG Chuanjiang, HAN Laixi, JIANG Xuedong, et al. Numerical simulation and optimization of circulation cup in direct coal liquefaction reactor[J]. CIESC Journal, 2017, (7): 2703-2712.
ZHANG Chuanjiang, HAN Laixi, JIANG Xuedong, et al. Numerical simulation and optimization of circulation cup in direct coal liquefaction reactor[J]. CIESC Journal, 2017, (7): 2703-2712.DOI: 10.11949/j.issn.0438-1157.20170195.
To solve blockage caused by coking in direct coal liquefaction reactors
a multi-phase model was developed to simulate two-phase gas-slurry flows around the circulation cup
which spatial flow parameters such as gas holdup were obtained. The simulation results indicated that the main driver for deposition and coking was aggregation and break-up of foams as well as foam mist blending associated with gas-liquid separation process. The relationship between extent of blocking in the circulation cup and gas holdup in downcomer showed that gas holdup in the downcomer was increased from zero to 34% as the extent of blocking was increased
leading to pump depletion. The finding on the cause of coking allowed further optimization on circulation cup structure. Simulation results showed that optimized design of circulation cup could effectively enhance gas-liquid separation with 14% gas holdup in the downcomer at extreme conditions and thus maintained stable operation. This work provides a reference for modifications on industrial equipment.