This paper is introduced an adress on some critical evaluations of on-line measurement qualities in Pulp and Paper Industry which was given at 9th Automation and Instrumentation Symposium in October 7th 1985 sponsord by Japan TAPPI.
This lecture contains five contents as follows;
1. Science of fiber-water dispersion; a physical meanings of consistency in pulp suspension
2. Characteristic properties of pulp suspension by means of optical method; some analysis of optical properties of pulp suspension by gonio-photometer
3. Some problems to measure the degree of beating of pulp; on-line tester to evaluate the internal and external-fibrillation of beated pulps
4. Flocculation and formation; how to evaluate the formation of sheet
5. Measurement of electrokinetic effects in paper making processes; a demand of an instrument capable of automatic and continuous measurement and recording of the streaming potential

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In this paper, a method of heat recovery to produce clean steam used as a general heat source from TMP waste steam is described and assessed whether investment in heat recovery system is feasible.

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Water retention value (WRV) and apparent density of pulp sheet are the valuable parameters of paper making, and are widely used in pulp evaluation. In order to elucidate the characteristics of Na0C1·peroxide bleaching, the composition and the various properties of bleached TMP, such as WRV, apparent density and specific surface area ware investigated. Changes of the morphological structure of bleached long-fibers in TMP were also studied by scanning electron microscopy.
Relationship between WRVof never-dried TMP bleached by Na0C1, Na0C1·H₂0₂0 and NaOCl·O₃ systems and apparent density of the pulp sheet was almost a linear function. WRV of never-dried TMP increased gradually by treating with increase in concentration of NaOCl solution under mild conditions. WRV of NaOC1-treated TMP further increased by H₂O₂ or O₃ bleaching. WRV of fines in bleached TMP was higher than that of the long-fiber fraction.
The influence of pH on WRV of bleached TMP was attributed to the difference of the amount and the dissociation of acidic groups, particulary uronic acids, in the pulp and the subseqent swelling.
Relationship between WRV and specific surface area of bleached long-fibers separated from TMP indicated that, at higher yield, specific surface area of the fibers increase more quickly during the mild bleaching described above, whereas the increase of WRV is less. On the other hand, WRV of the bleached fibers at low yield was higher.
From the results, it is concluded that WRV of bleached TMP depends on the chemical composition and the physical state of the pulp. WRV increased along with increasing hydrophilicity of TMP by removing lignin and hemicellulose. The dissolution of both components from the fiber surface by mild NaOCI and Na0Cl·peroxede bleaching caused the rapid increase of specific surface area of TMP.
Changes of the morphological structure of long-fibers showed that the fibrillation on the fiber surface related to the specific surface area occurs by mild bleaching with Na0C1speroxide, whereas the delamination of the cell wall of the fibers is caused by lignin removal during violent bleaching.

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The volatile compounds produced by pyrolysis of cigarette paper composed of flax pulp and wood pulp (mix ratio 9/1) on addition of various burning chemicals (organic acid salts and phosphates) in helium atmosphere at 650°C were investigated by pyrolysis gas chromatographic analysis.
The volatile compounds in pyrolysis products of cigarette paper with burning chemicals were almost same as those of cigarette paper without additives. A distinct difference in yields of volatile products was observed at 1% addition of burning chemicals.
The following results were obtained. The yields of eight degradation compounds including one unknown compound (crotonaldehyde. No.4, 2-furaldehyde. No.47, 5-methyl-2-furaldehyde. No.69, unknown. No.111, 3-hydroxy-4H-pyran-4-one. No.149, unknown. No.202, 3, 5-dihydroxy-6-methyl-4H-pyran-4-one. No.205 and 5-hydroxymethy1-2-furaldehyde. No.247) decreased, while those of 3 compounds (acetol. No.18, succinaldehyde. No.40 and r-butyrolactone. No.80) increased. These were all carbonyl compounds.

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This paper deals with the dimensional stability of paper containing high-yield pulps. The water retention value of some high-yield pulps, hardwood bleached kraft pulp (LBKP) and stone ground wood (SGP), the wet expansivity of the sheets and the effect of drying conditions on the sheets were studied. The results obtained are summerized as follows.
(1) The wet expansivity of the sheet made from hardwood high-yield pulps with a yield 82 to 85%, in spite of low density, was as large as that of the sheet from LBKP. This result was found to be caused by the high water retention value of the fines fractions in those high-yield pulps.
(2) During drying without tension, the shrinkage of the high-yield pulp sheets was equal to that from the LBKP sheet. But the shrinking stress of the sheets was much smaller than that of the LBKP sheet. For that reason the shrinkage of the sheet from those high-yield pulps was very dependent on the tension during drying.
(3) The dimensional stability of the paper containing high-yield pulps was more affected by the drying conditions on the paper machine.

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