Figure 1. Schematic diagram of experimental
setups
The ancillary equipment for the whole experimental system includes the
gas and liquid flowmeters, air compressor, liquid pump, and water tank.
All experiments done in this study are in the cold flow manner, and the
gas, liquid and solid phase are air, water and spherical particles,
respectively. Provided by the air compressor, the gas is metered by the
rotameters and enters radially into the bed through the gas distributor.
The water, pumped by the multistage pump, is metered by the
electromagnetic flowmeter then evenly sprays into the column on the top
of the particles through the nozzles. Spherical particles with an
average diameter of 2.4 mm, saturated water absorption of 21% and a
bulk density of 1.04 g/cm3, are continuously added
into the top of the bed from the silo. This reactor operates in a
downflow state: the gas, liquid, and solid phases flow cocurrently
downward through the bed after pre-distribution and exit from the bottom
of the bed. The outlet pipe is open to the atmosphere to vent out the
air. The solid flow rate is controlled by a gate valve on the central
outlet pipe and measured by weighting. To identify the solid flow rate,
first, collect and weigh all the liquid and solid flowing out within a
certain time, and then subtract the liquid to obtain the mass of
saturated water-absorbing particles. It is worth saying that the mass of
liquid flowing out of the bed is easy to be acquired by the liquid
flowmeter since the mass of liquid flowing out of the bed in unit time
is equal to the liquid injection rate in a steady state. The experiments
are carried out at room temperature (25±1℃) and near atmospheric
pressure. The range of the operating conditions in this study is shown
in Table
2.