This paper reviews briefly on the research of novel pulping processes, such as biological pulping, organosolv pulping and explosive pulping.

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The Environmental Pretection Committee of the Japan Paper Association has collected and arranged the data on the protection and improvement for these ten years from the Diet in 1970 where discussed the the typical seven environmental pollutions.
The copy of the hand writing manuscript for these arranged data were sent to the each company which had helpt to collect the informations, but these data did not appear in proper print form unfortunately.
As it is too sorry to neglect these valuable data, Environmental Improvement Technical Committee of J. TAPPI decided to publish the summary of the section 2, “Situation of the Environmental Protection in the Pulp and Paper Industry”, Which is the most important part in the original manuscript. The section 2 is devided into six parts, Region Environment, Air Pollution, Water Pollution, Odor, Noise and Vibration, and Waste, and summary of each part written by different authors will be reported one by one. We are quite happy for you to use these paper for the guide to respect of the past and prospect of the future.

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Matsumoto Mill of Honshu Paper Co., Ltd. manufactures solely corrugated containerboard ; kraft liner, jute liner, color liner and white liner
This mill, which is located in the western region of Matsumoto City, Nagano Prefecture, central part of Japan, started up in 1933 as “Matsumoto Shoshi Kogyosho” (Matsumoto Papermaking Factory) and changed its name to “Toshin Paper Co.” in 1943.
Matsumoto Mill now has 2 paper machines and its production is 330 tons per day of corrugated containerboard.
The mill site area is about 61, 000m² and the number of employees is about 230.
The wastewater from the mill is treated by a clarifier, flotation equipment, an aeration system for BOD treatment, and a sludge incinerator. Flue gas is treated by a water scrubber.

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Service strength of heavy duty paper sack at drop test is influenced by relative humidity, drop height, weight of filled content and number of paper plies in addition to strength of paper.
In this paper influence of weight of filled content was chiefly investigated. Influences of number of paper plies and drop height were also discussed.
Experiments on influence of weight of filled content on the service strength of paper sack were carried out on the pasted valve type paper sack, using two kinds of contents, portland cement and fertilizer, and changing length of paper sack and weight of filled content.
Defining an apparent density ρ_app. for filled content dependent on kinds of contents, repeated dropping times at failure of sack ν was expressed with the apparent density ρ_app. and weight of filled content W in the next formula according to multiple regression analysis.
lnν=5.17-5.89lnW/V₀+0.96lnρ_app.
Where V₀ is a volume of an original (unfilled) shape of paper sack. The original shape of paper sack is assumed to be an orthogonal hexahedron of length a₀, face width b₀ and bottom width h₀. (V₀=a₀×b₀×h₀)
An apparent density ρ_app. is defined as W₀/V₀, where W₀ is the weight of content filled in the original spape, an orthogonal hexahedron, of paper sack.
An influence of paper plies p on the service strength ν of paper sack was experimentally studied and influence of drop height H on the service strength of paper sack was discussed based on some data of earlier reports.
It was found that linear relationships exist between ln p and ln ν, and also between ln H and ln ν.
Repeated dropping times at failure of paper sack was expressed with the next formula as functions of paper plies p, drop height H, weight of filled content W and an apparent density of filled content.
ν=c·P^α·ρ_app^δ/H^βW^γ
where c, α, β, γ, and δ are constants.

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With a view to visualize and evaluate quantitatively the phenomena in flowing pulp suspensions that are difficult or impossible to be seen by the conventional means, a digital image processing system was developed by combining a microcomputer and an image memory unit.
The system is based on NEC's microcomputer PC-8001 (Z80 as CPU) with user's memory capacity (RAM) of ca. 19 KB when DISK BASIC is running.
The image memory unit permits conversion of an analog image to a digital image and its storage in image memories (32 KB RAM). The digital image consists of 256×256 pixels (picture elements) with 4 bits brightness levels (i. e. image of 16 halftones).
In order to extract some characteristics from digital images on real-time basis without using software, “Digitizing Level Controller (DLC)” was developed using the digital circuit technique.
DLC consists of the following circuits : (1) Control of image contrast and black (minimum brightness) level, (2) Pseudo-color dizitizing level (2, 4, 8) selection, (3) Black and white halftone digitizing level (2, 4, 8, 16) selection, (4) Reversal of digitizing levels (i. e., brightness and Pseudo-color).
The digitized image of pulp suspensions permits visualization of slight differences in pulp consistency by 8-level pseudo-colors or 16-level black and white halftones (greyscale). Even by 2 digitized levels, an object was clearly separated from its background.
Detailed techniques involved in developing this system are described.

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In this paper, a convenient method has been reformed which enables a quick, lightly labored and accurate analysis of acid-insoluble lignin (or Klason lignin ; abreviated to KL) in both woods and non-wood. The method in essentially based on the conventional standard quantitative determination of lignin (JIS (Japanese Industrial Standards) P8008-1976 and TAPPI standards T 222 os-74). The latters (JIS and TAPPI method) are now current ; however, is time consuming, and analytical procedures are comparatively cumbersome, and needs a lot of labor for the secondary hydrolysis step to apply especially when many samples must be analyzed. This paper deals with some analytical conditions (involving the primary and secondary hydrolysis conditions) with special reference to a poplar (Poplus Sieboldii Miq.) to establish the modification method.
The novel modification is suggested as follows : For the primary hydrolysis, about one gram of 4260 mesh wood or non-wood meal is admitted into a 18 × 105 mm test tube or a 50 to 100 ml beaker, and 10 ml of 72% sulfuric acid is pipetted followed by standing for 2 to 24 hr at 10 to 25°C with occasional stirring with a glass rod. For the secondary hydrolysis, the content is washed with 375 ml of distilled water into a 500 ml Erlenmeyer flask to make a final concentration of sulfuric acid of 3%. The flask is autoclaved for 30 min at 121°C (103 kPa) in a autoclave (sterilizer). Preheating of the autoclave is not necessary. Each flask is capped with alminum foil or alminum cap. The total (primary and secondary) hydrolysis can be completed within at least 4 hr, but the requisite hydrolysis time depends on the number of flasks. The procedures after the secondary hydrolysis are the same as the standard method prescribed JIS or TAPPI.
With a capacity volume of a 45l (300 mm in inner diameter and 630 mm in height) laboratory scale autoclave used in this experiment, about 15 flasks are able to be treated at once for about 1 hr, so that the modification is so adoptable especially when many samples need to be analyzed, swiftly, easily, and acculately.
The analyses by the modification method of lignins from four wood species and one non-wood species involving three hard woods (poplar, Poplus sieboldii Miq. ; beech, Fagur crenata Blume ; and white birch, Betula platyphylla Sukachev), a soft wood (japanese red pine, Pinus densiflora Sieb. et Zucc.), and a bamboo (Phyllostachys pubescens Mazel) are presented comparing with those by the standard method (JIS). For all tested samples, the values obtained by the modification are in full accord with those by the standard method. The measurement also seems to exhibit a good repeatability, though a few replicate values were obtained for each sample (Table 2 and Table 3).
But for the filtrates after secondary hydrolysis of some samples, the shapes of absorption curves in the ultraviolet region (190 to 300 nm) and acid-soluble lignin values are found to be more or less different between the modification method and JIS method. Furthermore, for the hydrolysis percents (ratios of monosaccharides winch have reducing power to polysaccharides in the samples), it is found that they are lower by both methods (JIS method, 74%; the modification method, 86%) in comparison with those by TAPPI method using GLC analysis.

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