5 results about "Chemical pulping" patented technology

The invention relates to a method for detecting the settling rate of a steamed wood chip, and belongs to a method for detecting the performance of the wood chip in a chemical pulping process by taking the wood chip as a raw material in the field of pulping and papermaking. By detecting the steaming efficiency, wood can be sufficiently softened to a proper degree, and the water content of the wood can be adjusted; the steaming time can be reasonably controlled, and unnecessary energy consumption is reduced. And meanwhile, the situation that the subsequent pulping cooking effect is affected due to the poor wood chip sedimentation effect caused by too short steaming time can be avoided. After the steaming efficiency is accurately detected and optimized, the subsequent pulping section can be carried out more smoothly, and meanwhile energy consumption caused by excessive steaming can be avoided.

Celluloses are taken from industrial trees by means of chemical pulp processing method which does not give damage to environment, and turned into fiber form, and fibers of industrial trees are turned into dental floss form. As said industrial tree; a kind of tree selected from beech tree, birch tree, poplar tree, elm and oak tree is used.

A method of purifying raw methanol obtained in chemical pulping, wherein heavy oil is admixed with the raw methanol to prevent precipitation, and the methanol mixture is distilled or evaporated to recover the methanol. The heavy oil is formed by mixing and heating raw methanol obtained from a side stream of chemical hardwood pulping with an acidic aqueous solution to vaporize low boiling point sulfurous compounds and provide acidified raw methanol. The acidified raw methanol is separated into a liquid top phase, a liquid aqueous middle phase, and a liquid bottom phase. The liquid bottom phase is extracted to obtain the heavy oil.

The present application relates to the field of chemical pulping, and discloses a method for simultaneously preparing kraft pulp and phenolated lignin, and kraft pulp and phenolated lignin prepared by the method. The method for simultaneously preparing kraft pulp and phenolated lignin comprises the following steps: mixing wood fiber raw material, water and cooking reagent, and then adding phenol; after cooking, obtaining a mixture of residue and black liquor; collecting the residue to obtain kraft pulp; and collecting the black liquor and performing acid precipitation, and the obtained precipitate is phenolated lignin. The phenolated lignin prepared by the present application has a phenolic hydroxyl content of 3.5-6.0 mmol / g, the kraft pulp prepared has a kappa number of 23.0-110.0, a viscosity of 900-1350 mL / g, and a brightness of 12.0-30.0% ISO. The present application has a significant lignin modification effect while separating fibers, realizes efficient utilization of resources and reduction of environmental burden, and has high industrialization potential.