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The aim of our contribution is to evaluate the possibilities for the biochemical utilization of paper wastes. We tested aerobic and anaerobic degradation of paper waste sludges from a plant that processes recycled paper. Testing included the assessment of phytotoxicity. We can conclude that the concentration of paper sludges did not have toxic effects on the bacterial consortium of the anaerobic or aerobic conditions. However, the leachate of paper sludges and water from sludge dewatering had a slightly negative effect on the germination of cress (Lepidium sativum L.) and lettuce (Lepidium sativum L.) seeds where the germination ranged from 83.3% to 100% but the mass yield was higher.

On the flaming combustion of highly densified cypress cylindrical briquette of which diameter/length ratio is 1/2 in the high temperature air, it was reported that the flaming combustion duration is proportional to the product of the inverse square of the specific surface area and the briquette density. However, the influence of biomass raw material on the combustion behavior is not clarified yet. To utilize various biomass as raw material of briquette fuel, the knowledge on this should be obtained. The objective of the present study is to confirm the influence of biomass raw material on the flaming combustion behavior, especially, the flaming combustion duration. Cypress, bamboo, rice husk and paper are used as raw material of the briquette. From the results of the thermogravimetric analysis and the estimation of lignin content in the biomass samples, it was observed that the activation energy decreases with increasing the lignin content. From the results of combustion experiments, it was found that the flaming combustion durations for each biomass raw material are proportional to the product of the inverse square of the specific surface area and the briquette density. It is suggested that these proportional constants have the correlation with the mass percentage of the cellulose in the biomass.

A prototype-rotary creaser was experimentally applied to an AB double-wall corrugated fiberboard to reveal creasing characteristics of the corrugated fiberboard and mechanical factors on failures of its height wise crease. Through this work, the followings were obtained. (1) There are appropriate combinations of pre-creaser gap and main-creaser gap for restricting the failure occurrences in the inside liner; (2) The pre-stage creasing for crushing corrugated medium was severely necessary for reducing the failures of the inside liner and performing the high-precision positionment for bending; (3) Dependency of water content and feed velocity on the failures of the inside liner was revealed.

This work deals the creasing characteristics of coated paperboard. It was not clarified to estimate the deformation behavior of creased line from the first peak bending moment Mp1 and the initial gradient C1 of bending moment. In this study, a new prototype testing apparatus has been developed for seeking the bending moment and the side view picture of creased part during repeated folding motion. The permanent (residual) deformation angles, the variance of residual stiffness and the hysteresis characteristics of bending moment were analyzed for the nominal shear strain (the scoring depth) γ . The obtained results were as follows: (1) C1 was characterized with γ, while the second term gradient C2 was characterized with γ and the inverse of tracking angle Θ-1. (2) By introducing the area of closed curve of second term hysteresis ACC, it is revealed that the gradient of ACC was remarkably varied with Θ at near the peak point Mp1.