8 results about "Kraft process" patented technology

The present invention is directed to fractionation of crude tall oil, which originates from the Kraft process black liquor. In the method according to the present invention, at least two strongly basic anion exchange resins are used to efficiently separate fractions from the crude tall oil.

The invention discloses a method for extracting lignin from sulfate pulping black liquor, which comprises the following steps: heating the black liquor to 50-70 DEG C in the stirring process, then adjusting the pH value of the black liquor to 3.0-4.5 by using organic acid, stopping adding acid, and aging under the conditions of stirring and 50-70 DEG C to obtain aged pulp; centrifuging the aged slurry, discarding the supernatant, collecting the precipitate, then washing the precipitate with acidic water, repeating the steps of centrifuging and washing for several times, and collecting the precipitate to obtain a crude lignin filter cake; and treating the obtained crude lignin filter cake in a phosphoric acid solution, washing the obtained product until the pH value of the filtrate is neutral, and then drying to constant weight to obtain the phosphorylated lignin. According to the invention, low vulcanization, high purity and functionalization (high thermal stability) of the product can be realized at the same time, so that the application barrier of the existing lignin is broken, and the huge potential of the lignin as a renewable resource is released.

The application discloses a method for preparing electronic-grade insulating pulp from bamboo, and relates to the technical field of insulating pulp production and preparation, and comprises the following preparation steps: step A, collecting bamboo raw materials in Hunan area; step B, flaking operation, bamboo is flaked and cut into pieces in a bamboo processing factory; step C, water washing operation, bamboo pieces are washed to balance water content; step D, cooking operation, bamboo pieces are cooked by adopting sulfite process, and the yield of the crude pulp is controlled to be 40-50%; step E, screening operation; step F, beating operation; step G, sheeting operation and strength detection. The method for preparing electronic-grade insulating pulp from bamboo has certain regionalism by adopting locally planted bamboo in Hunan, the prepared electronic-grade insulating pulp reaches the superior standard, and the prepared electronic-grade insulating pulp has the quality index that the conductivity is less than 3 us / cm by adopting deionized water for washing in the whole process.

The present invention provides a biobased and biodegradable cooking enhancement formulation for kraft pulping and a process for preparing the same. The formulation comprises lauryl alcohol ethoxylate, alpha olefin sulphonate, polysorbate-20, lactic acid, and water as essential components. The synergistic combination of these ingredients enhances delignification efficiency in kraft cooking by improving liquor impregnation, promoting oxidation through in situ peracid generation, and stabilizing oxidized lignin fragments through emulsification. The formulation enables efficient delignification at reduced active alkali concentration and lower cooking severity, thereby improving pulp brightness and yield while reducing rejects and pitch content. The biobased composition provides a non-toxic and environmentally safe alternative to conventional anthraquinone-based cooking aids and is completely biodegradable. The invention thus offers an effective and sustainable solution for improving kraft pulping performance and process efficiency.

The application relates to a method for efficiently preparing high-catalytic-performance biochar based on pulping black liquor and application. The application belongs to the field of high-value conversion and application of waste biomass. The purpose of the application is to solve the technical problem that the existing method cannot simultaneously realize efficient recovery of lignin in kraft pulping black liquor and conversion of excellent functional biochar. The method of the application is as follows: waste biomass is placed in a mixed solution of sodium hydroxide and sodium sulfide and heated at high temperature to obtain black liquor; iron chloride hexahydrate is added to the black liquor, heated for reaction, centrifuged, dried, and then pyrolyzed at high temperature in a tube furnace. The application takes the preparation of high-value products after lignin separation and recovery as a goal, adopts corresponding means to precipitate lignin and endow the lignin with product conversion potential, fully utilizes the sulfur element existing in the black liquor, simultaneously introduces other metal elements, and further obtains excellent functional biochar by optimizing process parameters. The obtained biochar is used for catalyzing peroxymonosulfate to degrade antibiotic wastewater.

This invention belongs to the field of pulping and papermaking technology, and provides a method for constructing a model of component leaching in acacia wood pretreated with microwave-assisted hydrothermal treatment and a method for pulping it. The model was constructed using the component leaching content as a parameter after microwave-assisted hydrothermal pretreatment of acacia wood. The F-value was 161.6355, P < 0.05, reaching a significant level, indicating a very good fit. The R-value of the model is... 2 The value was 0.9728, and the mean square error was 0.0318, indicating a reliable prediction result. The treated acacia wood chips were then subjected to sulfate pulping. The pulp was screened, beaten, defatted, and then processed into paper. The prepared paper exhibited excellent properties, with a tear index of 2.76–7.36 mN·m. 2 / g, tensile index is 44.4-102 N·m / g, burst index is 1.91-6.12 kPa·m 2 The ring compression index is 9.77–14.67 N·m / g. This invention provides a powerful tool for evaluating pretreatment effects and optimizing process parameters, further enhancing the scientific rigor and practicality of the research.

A method for separating water and at least one lignin fraction, lignin derivatives, low-molecular carboxylic acids, sodium sulfate, or a mixture thereof from filtrates originating from a black liquor of a kraft process. Black liquor is concentrated to a solids content between 25 and 55 wt. %. A first separation step, polymer lignin with a number average of the molecular mass distribution of >6 kDa is precipitated and filtered out by lowering the pH value of the black liquor, a first filtrate is obtained which is acidified with sulfuric acid; a formed precipitate consisting of lignin is separated by means of filtration; a second acid filtrate is obtained, cooled to a temperature less than 10° C., a fraction consisting substantially of inorganic salts is crystallized out; the formed precipitate is filtered off, a third filtrate is obtained which contains low-molecular carboxylic acid-soluble lignin and groups of the inorganic salts.

The invention relates to the field of sewage treatment, in particular to a treatment method for secondary sedimentation tank float sludge initiated by a DCM control agent in sulfate pulping. The method comprises a step of adding a fusion protein as shown in SEQ ID NO.3 into a secondary sedimentation tank, and further comprises the following steps: regulating the concentration of dissolved oxygen to 2.0-4.0 mg / L, the temperature to 35-40 DEG C and the pH value to 6.8-7.2, hydrolyzing extracellular proteins or extracellular polysaccharides generated by various zoogloea bacteria in the secondary sedimentation tank, destroying a foam skeleton and reducing adhesion of microhyphae, thereby realizing the purpose of removing the microhyphae in the secondary sedimentation tank. And the problem of'combined action of a DCM control agent and filamentous bacteria 'is solved, and the problem of float sludge in a secondary sedimentation tank is solved.