Abstract: A process and apparatus for producing pulp from impregnated cellulose-containing starting materials such as wood, straw, grass, waste materials etc. in a compacting apparatus comprising a shell (1) and two mutually opposite pistons (4, 4') contained in the shell. The material to be compacted is disposed between the pistons and constitutes a resistive electrical load. The pistons are movable relative to each other and the shell is movable relative to the pistons. The impregnated starting materials are digested at a relatively low hydromodulus of 0.5 to 2 with a direct action of heat on the impregnated starting materials in the compacting apparatus at a digesting temperature of 160.degree. to 300.degree. C. The digesting times are short and depend on the digesting temperature.

Abstract: This invention relates to a carrier material for photographic purposes which is formed of paper coated with a synthetic resin. The paper contains a water soluble inorganic salt that enhances its drying by microwaves. In a preferred embodiment, the paper contains starch.

Abstract: A process for the delignification and bleaching of lignocellulosic pulp employing electronically excited oxygen generated in situ which comprises subjecting an aqueous slurry of said lignocellulosic pulp having a consistency of from about 0.01% to about 10.0%, by weight of oven-dried pulp, and whose slurry pH is between about 8 and about 13 to irradiation with ultraviolet light while admitting oxygen into said slurry.

Abstract: A one-stage oxygen delignification system in which wood chips are first pressurized with oxygen and the oxygen allowed to reach equilibrium within the chips before the addition of cooking liquor. Cooking liquor is added to the chips while they are maintained under the pressurized oxygen. After the addition of cooking liquor under pressure, the oxygen pressure may be further raised. The cooking liquor may be at cooking temperature when added, or the slurry may be raised to cooking temperature after the liquor is added or after the additional pressure has been applied. The pressure may be pulsed by lowering and raising it during cooking.

Abstract: The process for producing pulp according to the present invention consists in the subsequent steps of an aqueous treatment of a vegetable stock at a temperature within the range of from 110.degree. to 170.degree. C. under a pressure of from 2 to 7 atm.g. for a period of from 0.3 to 4 hours at a weight ratio of the vegetable stock to water of 1:2-4 respectively; a simultaneous impregnation and cooking of said vegetable stock in a solution of nitric acid at a temperature of from 70.degree. to 90.degree. C. for 0.5-3 hours; cooking at a temperature of from 100.degree. to 130.degree. C. under a pressure of from 1 to 4 atm.g. for 0.3-0.5 hour; an alkali extraction of the vegetable stock; decontamination of the gaseous cooking products by mixing thereof with the air in a volumetric ratio of 1:0.5-1 respectively, and treatment with the spent liquor resulting from the stage of alkali extraction.

Abstract: Chemical cellulose is produced by treatment in a digester. In the first step, wood in the form of chips is treated for a period of about from 15 to 90 minutes with a cooking acid of a calculated amount of below 5% by weight and at least 2.5% by weight of SO.sub.2 and a mole ratio of SO.sub.2 to MgO or CaO of from about 2 : 1 to 3.5 : 1 at a temperature of from about 45 to 90.degree. C. The liquid SO.sub.2 is fed into the digester until the total SO.sub.2 content of the cooking acid is from about 6 to 10 percent by weight, and completing the digestion in a second step to obtain a pulp by cooking at a temperature of above 110.degree. C., and working up the pulp in a manner known per se to obtain chemical cellulose.

Abstract: In a method for examining pulp for the presence of shives therein a suspension of the pulp is passed through a measuring duct with transparent walls and at least one beam of light having a wavelength within the intra-red range from 750 to 950 nm is directed through the measuring duct perpendicularly to the direction of flow of the pulp suspension therein. The intensity of the light beam after its passage through the measuring duct is measured by means of a photo detector and the output signal of the photo detector is analyzed with respect to amplitude variations therein. The measurement is independent and insensitive to the type of pulp.

Abstract: A process is provided for freeing cellulose fibers from lignocellulosic material, which comprises subjecting particulate lignocellulosic material to irradiation at a frequency within the range from about 10 to about 300,000 MHz (megahertz), at an intensity of at least 0.5 megajoule per kg. of material, applied in a short pulse having a duration of at most 0.1 second, at such an intensity the water present in the lignocellulosic material is rapidly and even explosively vaporized, and disrupts or destroys the natural structure of the lignocellulosic material, thereby freeing the fibers substantially without deleterious effect upon the length or strength of the fibers.

Abstract: A process for the preparation of cellulose fibers from cellulose containing chips wherein the cellulose containing chips are subjected to a chemical process for the purpose of separating the cellulose from lignin and other extraneous chemicals which prior to digestion of the chips subjecting the chips to a two-step pre-treatment by:1. contacting said chips with an aqueous solution of an alkali metal, alkaline earth metal or ammonium sulfite or bi-sulfite metal; and,2. thereafter radiating the so pre-treated chips by contacting them with charged particles.

Abstract: A method is provided for controlling the amount of oxidizing bleaching agents in liquors used within the cellulose industry, as in the bleaching of sulphite, sulphate, mechanical, chemimechanical, semichemical or similar cellulose pulps, and in related industries, and particularly for controlling the addition of oxidizing bleaching agents to the system during the bleaching of cellulose pulp by mixing such liquor with at least one chemiluminescent reagent which reacts with the oxidizing bleaching agents in a manner to emit light. The amount of oxidizing bleaching agents in the liquor is then determined by comparison of the light intensity thus obtained with the light intensity for previously measured calibration values corresponding to known quantities of such oxidizing bleaching agents, and then from such determination controlling the addition of such oxidizing bleaching agents to the liquor.

Abstract: Municipal solid waste is treated by a method in which pollution of air, water and soil is minimized. Light, long fiber paper pulp which is in great demand and fertilizer which controllably releases its nutrients are recovered which render the treatment efficient and economical. The solid waste after removal of ferrous and non-ferrous metals, glass and other aggregates, is sonically pulped to prevent shearing of fibers using such chemicals that when subsequently phosphated, and xanthated if desired, will cause salts to precipitate with inks, coatings and waxes removed from the fibers to provide fertilizers with controlled nutrient release on the one hand and high quality paper pulp on the other.