A method for preparing an aqueous suspension may include providing a fibrous substrate comprising cellulose having a Canadian Standard freeness equal to or less than 450 cm.sup.3, and microfibrillating the fibrous substrate in an aqueous environment by grinding in the presence of a grinding medium consisting essentially of mullite. The grinding may be carried out in the absence of grindable inorganic particulate material. The grinding medium may be present in an amount of at least about 10% by volume of the aqueous environment. The microfibrillated cellulose may have a fibre steepness of from about 20 to about 50.

A method for preparing an aqueous suspension may include providing a fibrous substrate comprising cellulose having a Canadian Standard freeness equal to or less than 450 cm.sup.3, and microfibrillating the fibrous substrate in an aqueous environment by grinding in the presence of a grinding medium consisting essentially of mullite. The grinding may be carried out in the absence of grindable inorganic particulate material. The grinding medium may be present in an amount of at least about 10% by volume of the aqueous environment. The microfibrillated cellulose may have a fibre steepness of from about 20 to about 50.

A sheet manufacturing apparatus includes a screening unit having first openings for screening a defibrated material that is defibrating-processed; a refining unit that has second openings having sizes equal to or greater than sizes of the first openings and refines the defibrated material passing through the screening unit by causing the defibrated material to pass through the second openings; and a deposition unit on which the defibrated material passing through the refining unit is deposited.

In a method for producing nanofibril cellulose, cellulose based fiber material, in which internal bonds in the cellulose fiber have been weakened by chemical modification, are supplied, for separating fibrils, through several counter-rotating rotors outwards in the radial direction with respect to the rotation axis of the rotors in such a way that the material is repeatedly subjected to shearing and impacting forces by the effect of the blades of the different counter-rotating rotors, whereby it is simultaneously fibrillated.

In a method for producing nanofibril cellulose, cellulose based fiber material, in which internal bonds in the cellulose fiber have been weakened by chemical modification, are supplied, for separating fibrils, through several counter-rotating rotors outwards in the radial direction with respect to the rotation axis of the rotors in such a way that the material is repeatedly subjected to shearing and impacting forces by the effect of the blades of the different counter-rotating rotors, whereby it is simultaneously fibrillated.

The present invention provides a process for the preparation of essential oil modified nanocellulose and applications thereof. The invention further provides a process wherein the essential oil is covalently bonded with the nanocellulose such that the essential oil does not leach out. The edible coatings comprising the developed essential oil modified nanocellulose thus exhibit a prolonged antimicrobial effect.

The disclosure belongs to the technical field of papermaking technology and waste comprehensive utilization, and specifically relates to a method for preparing biomechanical unbleached pulp from wheat straw and full utilization of by-products thereof. In the present disclosure, wheat straw is used as raw materials for pulping, and treated by hot water, then a trace of KOH is added, the temperature of the wheat straw after heat saturation and softening is adjusted, alkaline compound enzymes is added for biological treatment, and refining of wheat straw is performed at last. The mechanical pulp meets the production requirements for unbleached packaging paper and paper-based materials, meanwhile, the by-products are recycled to prepare a biomass compound fertilizer, turning solid waste into treasures, and realizing a high value full utilization of wheat straw. Thus a good practical application value and a broad application prospect are performed.

The disclosure belongs to the technical field of papermaking technology and waste comprehensive utilization, and specifically relates to a method for preparing biomechanical unbleached pulp from wheat straw and full utilization of by-products thereof. In the present disclosure, wheat straw is used as raw materials for pulping, and treated by hot water, then a trace of KOH is added, the temperature of the wheat straw after heat saturation and softening is adjusted, alkaline compound enzymes is added for biological treatment, and refining of wheat straw is performed at last. The mechanical pulp meets the production requirements for unbleached packaging paper and paper-based materials, meanwhile, the by-products are recycled to prepare a biomass compound fertilizer, turning solid waste into treasures, and realizing a high value full utilization of wheat straw. Thus a good practical application value and a broad application prospect are performed.

[Object] To provide a fiberboard manufacturing method that is suitable for efficiently manufacturing a fiberboard in which warpage is suppressed, and to provide a fiberboard that is obtained by such a fiberboard manufacturing method.

[Solution] The fiberboard manufacturing method of the present invention includes the following pulp crushing step S1, mat forming step S2, and hot-pressing step S3. In the pulp crushing step S1, pulp dispersed in water is beaten in a gap between opposed blades to thereby produce a plant-based fiber material that has a particle size D50 of 50 to 110 μm and a freeness value of 150 to 300 ml and that contains an adhesive component. In the mat forming step S2, a mat is formed from the plant-based fiber material. In the hot-pressing step S3, by hot-pressing the mat, a fiberboard is formed from the mat through a process of plasticizing the adhesive component in the mat.

[Object] To provide a fiberboard manufacturing method that is suitable for efficiently manufacturing a fiberboard in which warpage is suppressed, and to provide a fiberboard that is obtained by such a fiberboard manufacturing method.

[Solution] The fiberboard manufacturing method of the present invention includes the following pulp crushing step S1, mat forming step S2, and hot-pressing step S3. In the pulp crushing step S1, pulp dispersed in water is beaten in a gap between opposed blades to thereby produce a plant-based fiber material that has a particle size D50 of 50 to 110 μm and a freeness value of 150 to 300 ml and that contains an adhesive component. In the mat forming step S2, a mat is formed from the plant-based fiber material. In the hot-pressing step S3, by hot-pressing the mat, a fiberboard is formed from the mat through a process of plasticizing the adhesive component in the mat.