Rectangular chambers

Mobile-phase velocity is higher with forced-flow development than in capillary-flow TLC. The actual flow rate is influenced by the type of chamber (rectangular or sandwich, saturated or unsaturated), the pressure and solvent viscosity (OPLC), or the rotational speed (RPC) (Nyiredy et al., 1988a). Nyiredy (1992) discussed the relation among resolution, separation distance, and time for forced-flow planar chromatography compared to capillary flow. It was stated that for separation of nonpolar compounds by FFPC on silica gel, a separation time of 1—2.5 min over a separation distance of 18 cm can be used without great loss in resolution. By contrast, longer separation times are needed for separation of polar compounds. 

A more recent development is the carbottom furnace, which is an above ground rectangular kiln the bottom is mounted on wheels and set on tracks so it is movable. The carbottom is isolated from the heating chamber by a water seal. These furnaces provide improved temperature and pressure control and better uniformity. 

Example 5 Radiation in a Furnace Chamber A furnace chamber of rectangular paraUelepipedal form is heated hy the combustion of gas inside vertical radiant tubes hningthe sidewalls. The tubes are of 0.127-m (5-in) outside diameter on 0.305-m (12-in) centers. The stock forms a continuous plane on the hearth. Roof and end walls are refractory. Dimensions are shown in Fig. 5-20. The radiant tubes and stock are gray bodies having emissivities of 0.8 and 0.9 respectively. What is the net rate of heat transmission to the stock by radiation when the mean temperature of the tube surface is SIG C (1500 F) and that of the stock is 649 C (1200 F) ... 

The velocity of the air, flowing through the fan, can be as much as 3 to 4 times the velocity across the face of the tube bundle. Also, the air, coming from the circular shape of the fan, must be distributed across the square or rectangular shape of the bundle. The air plenum chamber is intended to make this velocity and shape transition, such that the distribution of air is uniform across the bundle. Common practice is to install the fan in a chamber, such that the distance from the first row of the tube bundle to the fan is about one-half the fan diameter... 

The plenum chamber design may be a simple box shape, formed by flat sides and bottom, or curved transition sections may be used to obtain a tapered smooth transition from the rectangular bundle to the circular fan. Either design may be used for forced-draft or induced-draft air cooled heat exchangers. 

Technology Description Infrared radiators can be used as the heat source in the destruction of hazardous waste. This system (Figure 35) is made up of a primary chamber consisting of a rectangular carbon steel box lined with layers of a light weight. 

In preparative continuous free flow electrophoresis, continuous buffer and sample feed are introduced at one end of a thin, rectangular electrophoresis chamber. A schematic is presented in Fig. 11-5. The sample stream is usually introduced through a single port while buffer is introduced through several ports, essentially producing a buffer curtain . Because the buffer streams are introduced independently, it is fairly easy to establish a variety of gradients (e.g., pH, density, ionic strength) across the buffer curtain . 

Type of flow-through Rectangular chamber triangular slit-type Device outer dimen- 20 mm 16.5 mm sions diameter height... 

EC, electrode cells EC, filling chambers SP, silicon packings C, rectangular capillary M, microporous PTFE membranes E, platinum planar electrodes S, stoppers [68. ... 

Linear development is carried out in the ascending or horizontal mode in a saturated (lined with thick hlter paper) or unsaturated [8] rectangular chamber... 

A schematic of the apparatus developed is shown in Fig. 3. Stirrers mix and push the lighter and heavier phases in each compartment, with the maximum rotation speed governed by the need to maintain the interface steady. Flow deflectors ensure that the phases are circulated in each chamber and that flow near the interface is laminar. The interfacial plate (thickness 2 mm) is rectangular with a hole at its center. The distance from the interface to the flow deflectors is less than 6 mm. The two phases are analyzed by withdrawing small volumes via sampling holes. 

The by-product process involves essentially by-product coke ovens which can be the waste heat ovens or regeneration ovens. They are designed to produce coke as well as to recover the products of carbonisation. The ovens are narrow rectangular refractory chamber. The ovens are heated from both sides through vertical flues. The necessary heat is produced by burning gases inside the narrow flue chambers. The ovens are the coking chambers and... 

The basic construction consists of a rectangular or cylindrical steel chamber, lined with refractory bricks. Tubes are arranged around the wall, in either horizontal or vertical banks. The fluid to be heated flows through the tubes. Typical layouts are shown in Figure 12.69a, b and c. A more detailed diagram of a pyrolysis furnace is given in Figure 12.70. 

The attraction between the air bubble and contaminants is believed to be primarily a result of particle surface charges and bubble size distribution. The more uniform the distribution of water and microbubbles, the shallower the flotation chamber can be. Generally, the depth of effective flotation chambers is between 0.9 and 2.7 m (3 and 9 ft). Flotation units can be round, square, or rectangular. Gases other than air can be used. The petroleum industry has used nitrogen, with closed vessels, to reduce the possibilities of fire. Ozone can be fed through with air for more efficient reduction of soluble iron, VOCs, and so on.57 Ozone-UV flotation is another alternative for groundwater decontamination. 

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