In the 1st report, the drying model of a wet sheet and the formulation of drying speed, expressed as a function in the drying factor, have been discussed on a multi-cylinder dryer section. For the practical use of the drying model, three items are studied.
1. From the experimental result of canvas drying in a laboratory scale, a simplified formula, delivering variations in water contents of a canvas, is obtained by a vapour removal roll.
2. The pocket's moist condition is determined more accurately by solving the equation of heat and mass equilibrium.
3. It is proved that in a comparison between the computed value and the data in an operating condition, the drying model is available for actual simulation of water contents and of temperature distribution in a wet sheet and canvas.

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It is usual that the pulp mill effluent is treated by means of Fe (OH)₃ or Al (OH) ₃ flock flocculation and sedimentation. In testing the effluent, only COD, BOD and chromaticity are measured in many cases, and the influence of the components in the effluent is nearly left alone. The authors, however, used magnesium components in treating the pulp mill effluent, and measured anionic colloid contents in the effluent by means of a colloidal titration method, and also made measurement of saccharide. The relationship among the added magnesium content, the removal ratios of the COD, colloid and saccharide concentration, the sedimentation rate of sludge, and the sludge volume was carefully investigated, and as a result, the authors were able to have a prospect of putting an effluent treatment method into practical use.
Stated below is the information obtained from the tests carried out by the authors.
(1) The magnesium hydroxide method is relatively superior in the sedimentation and filtration rates to the aluminum hydroxide or the ferric hydroxidemethod.
(2) The anionic colloid in the effluents of Kraft Pulp (KP), Sulfite Pulp (SP), Semichemical Pulp (SCP) and Fermentation Pulp can be completely removed by means of magnesium hydroxide.
(3) The removal of the COD in magnesium hydroxide method is about 70% in the cases of the KP and SCP effluents, and about 55% in the cases of the SP and Fermentation Pulp effluents.
(4) Residual COD loading components are estimated to be lower in molecular weight of organic compounds in the pulp mill effluent.

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