In current view of energy saving, the studies on biological pulping become more attractive in people of pulp industry.
The origin of biological pulping is natural degradation of lignin by a white rot fungus, which remains white cellulose in the decayed trees or logs in forest. While the last several years, researches of biodegradation of lignins and of these applications have been increased, and an international seminar on lignin biodegradation in US-Japan Cooperative Science Program 1978 was held at the U. S. Forest Products Laboratory, Madison. The proceedings of that seminar provide many fundamental principles for biological pulping.
Suitable microorganisms, culture conditions and enzymic mechanisms for accelerating degradation of lignin are important and outlines of the recent relative reports are reviewed.
It is noticeable that degradation of lignin by white rot fungus goes forward with consumption of co-substrates ; cellulose, hemicellulose or the other carbon sources. The requirement of co-substrates for biodegradation of lignin is one of problems for practical biological pulping.
Eriksson and Vallander studied on biomechanical pulping. They have a mutant strain of the white rot fungus, Sporotrichum pulverulentum, which produce no cellulase. The strain of the fungus is applicable for pretreatment of thermomechanical pulping and their studies showed that about 30% energy could save at the pulp production from chips of birch, rotted for 12 days by the fungus.
Of the white rot fungi, there are the fungi having bleaching ability. Using several these fungi and edible mushroom fungi, an investigative study was carried out to estimate properties and yields of the biochemical pulps in our department. The pulps were made from rotted chips of Quercus serrata by SCP or KP digesting method. Our study showed that the yields of the pulps decreased by 410%, but the brightness increased. The properties of the biochemical pulps were almost equivalent with control chemical pulps and some of the pulps rather increased the strength.
These studies on the biological pulping suggest that good quality of pulps ; increasing strength and brightness, may be produced under energy and chemical savings.
An important technological problem on the biological pulping is how to cultivate the fungus in a mass of wood chips with homogenious and rapid growth of the mycelia. A device for mass cultivation is proposed, and needs of fundamental researches on the biological pulping are discussed and emphasized.

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While the world's oil situation appears increasingly precarious under the impact of the reduction of oil supply provoked by the Iranian coup and OPEC's successive price increase, the “Tentative prospect on the long-term demand and supply of energy” which was published by the Demand-Supply Subcommittee of the Government's Comprehensive Energy Survey Commission in August 1979, highlighted coal as the most realistic energy source in place of oil.
Our company, being the supplier of electricity located in the coal-producing region, has long committed itself to providing a stable supply of power primarily based on the coal-burning power plants, along the line of the national policy.
This paper describes the outline of the boilers in our existing coal-fired steam power plants, characteristics of the fuel coal, hauling methods and equipment, disposition and possible utilization of the cinder ash, and anti-pollution measures, and further relates on the necessary considerations on expanding the use of coal, notably on the design of boiler and antipollution measures in using overseas coal, as well as the present state and unsettled problems of novel coal combustion technology such as COM, with on aim of providing information that will be useful for the planning and implementation of a coal utilization project.

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Sanko Paper Mfg. Co., Ltd. established in 1937, is now composed of two mills (Sobue, Fuji) and three offices (Tokyo, Osaka, Nagoya). Sobue mill started its operation in 1939 is located on the left bank of Kiso river in the north west of Nagoya.
Sobue mill has continued to produce paper boards, only and to use raw materials of twenty percent pulp (domestic products, imports), and eighty percent waste papers.
The daily output of paper boards when the usualy operating four machines produce is 740 metric tons, of which 340 metric tons are coated white boards and 400 metric tons are jute liner.
There are 430 employers in Sobue mill which has 330, 000 m² areas of ground.

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It was found that the effect of multistage ozone bleaching was caused by the removal of ashes and resins from sulfate pulp with water in each bleaching stage.
The removal of ozone oxidized products of carbohydrates and lignin was synergistically effective in combination with the aforementioned removal.

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The effect of fiber dimensions of kuromatsu Asplund pulp on some properties of pulp, obtained by single-stage oxygen alkali pulping were studied. Yield, blightness, and kappa number were measured. With decreased fiber dimensions of Asplund pulp, yield, brightness and kappa number decreased and scattered respectively. So, it becomes evident that the reproducibility of the pulping results is affected significantly by the proportion of an fine size fraction (20 mesh pass fraction) in the starting materials. Therfore, to establish an generally accepted relationship between the cooking variables and pulp properties, (1) the fine size fraction should be removed as much as possible from the starting material, and (2) at least the amount of fine size fraction should be kept constant in the starting material.

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