Characteristics of Flow Behavior in Semi-Cylindrical Spouted Bed with Draft Tube.

Influence of contactor geometry and draft tube configuration on the cycle time distribution in sawdust conical spouted beds

“…A similar effect of wall slope on solid circulation has already been observed for sand particles in spouted beds with draft tube (Altzibar et al, 2013b) and without draft tube (Ijichi et al, 1988, Ijichi et al, 1990, Ijichi et al, 1998, Olazar et al, 1998. Furthermore, Figure 8a shows clearly the interaction between contactor angle and aperture ratio, which was mentioned in the comments concerning Table 4.…”

Hydrodynamic simulations of gas–solid spouted bed with a draft tube

“…(2) the annular bed that surrounds the draft tube where the particles move downward as a moving packed bed. Ijichi et al (1998) reviewed the flow characteristics of a spouted bed with a draft tube. The applications of spouted bed with a draft tube include coal combustion (Konduri et al, 1995), pneumatic conveying (Milne et al, 1992), pyrolysis of hydrocarbon (Stocker et al, 1989) and particle circulation (Ji et al, 1998).…”

Low temperature drying of pomace in spout and spout-fluid beds

“…This limitation is even more obvious when wet and sticky materials are treated in the fluidization units: in this situation, a separate control of gas flows to the spout (mainly acting as a mixing means, besides promoting effective mass transfer, though for a very short time) and to the annulus (where equilibrium between the moving phases can be easily reached, thus stopping the phenomenon) is desirable (Hattori et al, 2001). The addition of a draft tube (Arsenijevic et al, 2004;Hattori et al, 2001;Ijichi, Miyauchi, Uemura, & Hatate, 1998;Ishikura, Nagashima, & Ide, 2003;Ji, Tsutsumi, & Yoshida, 1997Khoe & Van Brakel, 1983;Muir, Berruti, & Behie, 1990;Osorio Revilla et al, 2004a;Osorio Revilla et al, 2004b;Stocker et al, 1989) has proven to act as a beneficial constraint and helps in terms of a better definition of both the gas distribution and the solids motion pattern during various processes such as drying (Khoe & Van Brakel, 1983;Tulasidas et al, 1993), coal gasification, combustion (Konduri et al, 1995, Konduri, Altwicker, & Morgan, 1999 pyrolysis of hydrocarbons (Stocker et al, 1989) and production of pharmaceuticals (Fukumori & Ichikawa, 1997;Littman, Morgan, & Morgan, 1997). A paste-like agglomerate surely benefits from such a geometrical configuration which assures the intermixing of the solids and close contact with the drying fluid medium.…”

“…A paste-like agglomerate surely benefits from such a geometrical configuration which assures the intermixing of the solids and close contact with the drying fluid medium. The flow characteristics of spouted beds equipped with a non-porous draft tube (SBDT) was revised by Ijichi et al (1998) and recently by Ishikura et al (2003), while some papers have studied solid circulation in the bed, and the hydrodynamics and the flow regimes that occur inside SB and SBDT Ishikura et al, 2003;Ji et al, 1997, Ji, Tsutsumi, & Yoshida, 1998Larachi, Grandjean, & Chaouki, 2003;Muir et al, 1990;Olazar et al, 1996;Yurong, Guangbo, Bouillard, & Huilin, 2004). Modifications to the classic scheme were adopted by Lim et al (1988), and by Hattori et al (2001) who adopted a second air feed in the annulus of their spout-fluid bed (SFB) which was sometimes equipped with draft tubes (SFBDT).…”

“…Modifications to the classic scheme were adopted by Lim et al (1988), and by Hattori et al (2001) who adopted a second air feed in the annulus of their spout-fluid bed (SFB) which was sometimes equipped with draft tubes (SFBDT). The effect of the entrainment length, the spout and fluidizing air flow rate on the solid circulation rate and on the amount of gas bypass were studied by Muir et al (1990), Olazar, San Josè, Izquierdo, deSalazar, and Bilbao (2001), and by Ijichi et al (1998). These authors showed that the fluidizing air can offer some benefits by increasing the solid circulation rate and reducing the gas bypass from the spout versus the annulus and vice-versa.…”