In the previous papers¹⁰⁾¹¹⁾ it was shown that liquid-side mass-transfer coefficients in a tower packed with Raschig rings were reasonably correlated as expressed by Eqs. (1), (2) and (3).
In this paper:
1) Taking the surface area of a Berl saddle to be a hyperbolic paraboloid based on Max Leva's idea⁶⁾, the wetted surface areas of Berl saddles (nominal dia.: 13mm and 50mm) were determined by a method similar to that employed by Mayo⁸⁾ or Fujita¹⁾. The results are shown in Fig. 3, from which was derived Eq. (6) for the wetted surface areas of 13mm Berl saddles, Eq. (7) for those of 50mm Berl saddles and Eq. (10) for their mean.
2) Absorption of pure CO₂ into city water was investigated, using a 10cm-dia. tower packed with 25mm Berl saddles. The results are shown in Fig. 4.
3) Liquid-side mass-transfer coefficients calculated from the data of Sherwood-Holloway¹²⁾, Molstad et al.⁹⁾, Fujita et al.²⁾, Hikita et al.³⁾, and the authors, by using Eq. (10) were reasonably correlated as shown in Fig. 5. The average line in Fig. 5 is expressed by Eq. (12), which is identical with Eq. (3) but for their constants.

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For the operation of a fixed-bed-type kiln, in which granules containing anthracite are charged, it is important to control the effective combustion rate.
There has been little information on the quantitative treatment of this problem, owing to the presence of many factors affecting the combustion rate, such as diameter and internal surface of granules, mean diameter, internal surface and specific surface of anthracite particles, content of fixed C in anthracite in granules, concentration of reactant gas, coefficient of reactant gas diffusion and combustion temperature. In the scope of the present experiments, thickness of gas film arouhd granules was found to be negligible.
Based on the experimental results and dimensional analysis, the effective factor for the combustion rate constant of anthracite particles in a granule was introduced (Eqs. (1) and (2)) as the function of dimensonless terms of factors (Eqs. (9) and (10)).
An experimental equation for φ was also shown under given conditions (Eq. (10-a)).

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Crushing was performed by dropping a steel ball or a steel hammer on a plunger, placed on cubic or powdery samples in a steel mortar, or by driving a ball mill at normal speed.
The authors applied the equations shown in their previous reports, -relation between number of blows, net work input to crushing, surface increment and size distribution of crushed products-to the results derived from their present experiment, and obtained, from Eqs. (1)-(4), the relations given by Eqs. (5)-(10). A close similarity was found between these relations and many other corresponding results obtained by the authors and by many investigators, such as Martin, Mittag, Chujo, Tanaka, Svensson Kuwai and others.

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