Perforated spargers distributors

There are three basic types of clean inlet gas distributors (1) a perforated plate distributor, (2) a bubble cap type of distributor, and (3) a sparger or pipe-grid type of gas distributor. The perforated plate distributor (Fig. 17-10d) is the simplest type of gas distributor and consists of a flat or curved plate containing a series of vertical holes. The gas flows upward into the bed from a chamber below the bed called a plenum. This type of distributor is easy and economical to construct. However, when the gas is shut off, the solids can sift downward into... 

Perforated-Pipe Distributors The simple perforated pipe or sparger (Fig. 6-34) is a common type of distributor. As shown, the flow... 

Use of efficient olefin feed distributors is also effective in reducing acid consumption. The conditions at the point of initial olefin contact with the circulating catalyst are very important because of the extremely rapid rate of the initial reaction. Perforated sparger rings are frequently employed, and a concentric feed nozzle is also a common feature 6). 

Internal pipe distributors are also known as perforated spargers or perforated pipe distributors or headers. They can be designed for either liquid only or two phase flow. A pipe distributor may be considered as liquid service if the volume of vapor is no more than 5%. 

Bubbler (agitation) A perforated pipe distributor for fluids or gases used in the bottom of fluid tanks for agitation. Also called a Sparger. 

Figure 3.29 Gas-phase distributors (a) porous plate, (b) perforated plate, (c) single-orifice nozzle, (d) spider-type sparger, and (e) multiple-orifice nozzle...

Slurry Reactors Slurry reactors are akin to fluidized beds except the fluidizing medium is a liquid. In some cases (e.g., for hydrogenation), a limited amount of hydrogen may be dissolved in the liquid feed. The solid material is maintained in a fluidized state by agitation, internal or external recycle of the liquid using pipe spargers or distributor plates with perforated holes at the bottom of the reactor. Most industrial processes with slurry reactors also use a gas in reactions such as chlorination, hydrogenation, and oxidation, so the discussion will be deferred to the multiphase reactor section of slurry reactors. 

Low-velocity vapor-only feeds often enter via bare nozzles or V baffles (above). At higher velocities, perforated vapor spargers are used. At high velocities, vapor horns and Schoepentoeters are often preferred. Alternatively or additionally, a vapor distributor may be mounted above the feed. The vapor distributor is a chimney tray (Fig. 14-72) where liquid is collected on the deck and flows via downcom-... 

At times, with vapor feeds, it may appear attractive to orient the distributor (sparger) perforations upward. In one case, this was successful in overcoming a hammering problem (item 4 above). The author feels that this practice is troublesome and should only be used as a last resort. The following considerations apply to spargers with upward-oriented openings ... 

A vapor distributor with insufficient pressure drop may be ineffective. A case has been reported (75) where poor column efficiency resulted from specifying a vapor distributor with lower pressure drop than recommended by the manufacturer. The vapor distributor (or vapor-distributing support) pressure drop can be minimized by entering the feed via a sparger pipe with the bottom quadrant removed (rather than perforated). Although such a sparger pipe will not be an effective vapor distributor, it will serve to break the incoming vapor jet and reduce its velocity head. 

Gas distributors used in BCs include (i) sintered, perforated, or porous plates (ii) membrane or ring-type distributors (iii) arm spargers or (iv) single-orifice nozzles. The sintered plate (Figure 7.12a), which is usually made out of glass... 

A bubble column is a simple and effective device for gasAiquid contact. It usually consists of a vertical cylindrical vessel with a gas distributor at the bottom, either a porous plate or a sparger (one or several perforated rings). Care should be taken that the gas flow is evenly distributed over the cross section of the... 

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