Bed divided

Instead of using separation data may be expressed in terms of a volume distribution coefficient ) , which is defined as the amount of solution in the exchanger per cubic centimeter of resin bed divided by the amount per cubic centimeter in the liquid phase. The relation between and is given by ... 

Pressure Drop. The pressure drop across a two-phase suspension is composed of various terms, such as static head, acceleration, and friction losses for both gas and soflds. For most dense fluid-bed appHcations, outside of entrance or exit regimes where the acceleration pressure drop is appreciable, the pressure drop simply results from the static head of soflds. Therefore, the weight of soflds ia the bed divided by the height of soflds gives the apparent density of the fluidized bed, ie... 

For installations with several storage tanks and a protection current of several tens of an mA, uniform protection current distribution should be the goal, so that the current injection occurs via a number of anodes distributed over the site or via a more distant anode bed. Dividing up the protection current over several anodes avoids large local anodic voltage cones and therefore effects on neighboring installations. 

For the discussion of this problem the extreme case of a bed divided in two halves will be used, with a different size of catalyst in each half... 

Bulk density. The mass of particles composing the bed divided by the volume of the bed [49]. Also referred to as the apparent density [5,49]. 

When the gas velocity through a bed of group A, B, C, or D particles increases, the pressure drop through the bed also increases. The pressure drop increases until it equals the weight of the bed divided by the cross-sectional area of the column. The gas velocity at which this occurs is called the minimum fluidizing velocity 1. After minimum... 

The available area corresponds to the cross-sectional area of the annular bed divided by the maximum possible area based on r0. 

Bulk powder density must be distinguished clearly from the true density of parti-eles. Bulk powder density is simply the mass of a powder bed divided by its volume. The volume of the powder bed ineludes the spaces between agglomerates, between primary particles, and the volume of micropores within the partieles. These voids... 

Growing vegetables in narrow beds, divided by access paths, has many advantages over traditional row cropping. On a traditional vegetable plot, soil improvers and fertilizers are applied across the whole area, and then dug in. The soil between the rows is compacted as crops are watered, fed, weeded, and harvested. A bed system breaks with this constant cycle of compaction followed by cultivation. 

The ignition front rate for the underfired case is defined as the initial weight of the bed divided by time of travel through the whole bed and the cross section of the bed. 

The freezing time must now be equal to the residence time in the bed (see Mixing, dispersion and residence time, below) a mean residence time can be assumed to be equal to the mass hold-up in the bed divided by the mass flow rate. If the mass hold-up is the product of bed volume and the bulk density of the bed, and the bed depth is H, then... 

In this type of bioreactor the substrate solution passes through a settled bed of particles held in a column and product emerges continuously at the far end. The degree of conversion is determined by the time the fluid remains in the bed and this contact time is determined by the free volume in the reactor bed divided by the flow rate through the column V/Fj. 

HUMIC Acid. Humic acid did not contribute detectable impurities to the eluates of blank parfait columns. This result was apparently due to the insolubility of humate in the organic solvents used to elute the Teflon and ion-exchange beds and the inability of the humate to volatilize in the GC. Humic acid did, however, distribute itself throughout the parfait column, as indicated by the observation of color entering the column effluent, F7. When 16 mg of humate in 8 L of synthetic hard water was passed through a parfait column having the Teflon bed divided into three sequential 50-mL beds, 8.9 , 5.0 , and 2.9 of the total humate were found in the aqueous phases that separated upon elution of these beds, as indicated by absorbance at 200 nm. The column effluent from this experiment contained 5.1 of the humate applied. The majority of the humate applied was found as color adsorbed to PTFE, and it did not elute into methylene chloride. Conditions to elute it from PTFE were not explored. 

The heat-transfer coefficient is a function of all chain, where heat flow passes, and for one-dimensional (plane model) heat exchange between liquid and hydride bed divided by heat-conducting wall can be expressed by ... 

Constitution Bed divides into dense phase + dilute phase, although surface of dense phase is ill-defined Density of bed is almost constant, surface of bed rather well defined... 

Solutions for the heat-transfer problem, which arises in the use of packed beds as direct-contact recuperative heat exchangers, were presented by Furnas in 1930. The parameter Njj is the number of heat-transfer units. For heat transfer, the dimensionless time t is the heat capacity of the gas times the amount of gas that has passed through the bed divided by the total bed capacity. For Nu = co, the breakthrough curve of T /Tq vs. t would be a vertical line at t = 1.0, just as for mass transfer. The defining equations are... 

Archimedes law is thus, in fact, valid for suspensions—but not for the reasons usually stated. Similar remarks apply to the usual proof that the pressure drop in a fluidized bed is equal to the net weight of the bed divided by the cross sectional area (B12, H8). Based on this analysis it seems likely that dilute, laterally inhomogeneous suspensions would display deviations from Archimedes law. 

Since various sulfuric acid concentrations were used in the study, a method to normalize its effect was developed. Conductivity ratio was calculated using equation 2 to mitigate the effect of sulfuric acid conductivity. The conductivity ratio is simply the ratio of the measured electrical conductivity of the agglomerate bed divided by the conductivity of the sulfuric acid solution used during agglomeration. 

When a powder just fills a vessel of known volume V and the mass of the powder is m then the bulk density of the powder is m/V. However, if the vessel is tapped in most cases the powder will settle leaving top empty space, so adding more powder would be necessary to end with the vessel completely filled. If the mass now filling the vessel is nt then the bulk density is m /V > m/V. Clearly, this change in density just described has been caused by the influence of the fraction of volume not occupied by a particle, known as porosity. The bulk density is, therefore, the mass of particles that occupies a unit volume of a bed, while porosity or voidage is defined as the volume of the voids within the bed divided by the total volume of the bed. These two properties are in fact related via the particle density in that, for a unit volume of the bulk powder, there must be the following mass balance ... 

The model is a box model consisting of the cylinder, the zeolite bed divided into 10 compartments and the head space of the packed bed. The mass balance of each box is written as follows. 

The solution to the problem was to replace the L-valve by a loop seal (Figure 16.3), which is essentially a fluidized bed divided by a vertical baffle except for a gap at the bottom to allow solids to pass between the two side-by-side beds, fluidized by separate air supplies. Hot lime particles fall into the bed nearest to the calciner, flow under the vertical baffle into the second bed adjacent to the cooler driven by the higher pressure in the first leg of the loop. The solids in the second bed then overflow into the cooler. This system operates like two arms of a manometer and there are fluidized solids present at all times in the loop preventing hot gas from passing direct into the cooler. 

Instead of fixed catalyst beds, fluidized beds may be employed. The size of the catalyst particles is then preferably about 0.1 mm, and high values of the effectiveness factor can be realized. The pressure drop across fluidized beds is moderate. It is equal to the weight of the bed divided by the cross sectional area of the reactor (see section 4,5,1 A). 

In many areas of powder technology, scientists need to characterize the properties of powder beds. Thus, in powder metallurgy and ceramics, the powder is poured into a container and then consolidated, either by heat or the application of pressure. The rate of consolidation, and the achievable consolidation are often governed by the structure of the spaces, known as pores, between the powder grains in the initial powder bed. When a powder is poured into a container, the volume of the freshly poured powder bed, divided into the weight of the powder is the apparent density of the powder bed or the aerated powder density. 

Equations have been developed to predict the efficiency of NO2 removal based on experience over many years with ceramic saddle-type packings, NO2 removal efficiency, as defined by Equation 5-14, can be related to the gas retention time (i.e., the depth of the packed bed divided by the superficial gas velocity). Empirically, suitable designs for such scrubbers employing water as the liquid phase are produced using ... 

Rock taken from the surface, which has been exposed to the atmosphere, is of an inferior quality to that found at a depth where it has been exposed to a strong pressure and is consequently denser. Therefore, in opening a quarry it is advisable to excavate upon a hill-side and come at once to the sound stone. Rock is generally found in beds, divided by joints or seams, at which the natural adhesion is broken and the layers are easily separated. When the quarry shows no natural line of separation, one may be produced by drilling a line of holes at equal distances from each other, into which conical steel pins are driven, and the stone splits the pins being placed in the plane of the required seam. 

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