146results about How to "Improve bleaching efficiency" patented technology

The invention relates to a method for boiling high concentration pulping in normal pressure or low pressure by an alkaline method with zero residual alkaline, and the method comprises adding accelerating agent in the boiling process and utilizing a double screw to rub and squeeze a pulper, leading pulp making and boiling process with an alkaline method to go on in normal pressure or low pressure, and leaving no residual alkaline in black liquor, leading pulp to always keep a higher density in the pulping process of boiling, washing and bleaching, and the pulp which is prepared can meets the requirement of paper making. Accelerating agent chooses one or a plurality of magnesium hydrate, potassium hydrate, sodium metasilicate, sodium sulfide, sodium sulfite, ammonium sulfite and carbamide. Special-purpose pulping boiling equipment and high-pressure boilers are not needed by pulping paper mills through utilizing the invention, in the process of pulping, pulp always keeps higher density, and black liquid has high density, little numbers and low energy consumption, alkaline recovery project with great investment is not needed to be built, and the invention enables black liquid to prepare fertilizer or other chemical products with high quality, and the invention is suitable for popularizing and applying.

A bark bleaching process; the steps are as follows that hydrogen peroxide, sodium hydroxide, sodium silicate and magnesium chloride are taken in I bleacher according to a certain proportion to make bleaching liquid: the bark is encased in a bark bleaching frame and the frame is soaked in the bleacher; a pump is adopted to continuously circulate the bleaching liquid in the bleacher; at the same time, steam is input for heating the bleaching liquid and the temperature is kept constant between 60 to 70 Celsius degrees; the constant temperature is kept for 4 to 6 hours; the bark bleaching frame is taken out of the in I bleacher and put into II bleacher filled with oxalic acid solution; a liquid compulsory circulation device is used to make the liquid in the bleacher continuously circulate; the bark bleaching frame is taken out after the frame is soaked for continuous 30 minutes; the bleaching frame is washed with pressed clean water and the drying treatment is implemented at last. The present invention also discloses a special bark bleaching frame and snakelike parting strip for angle steel welding. The present invention boasts of low investment on equipment, high production efficiency and excellent bleaching effect.

The invention relates to a poplar ultrasonic chemical mechanical pulping technique. The pulping technique includes the steps: performing ultrasonic pretreatment on steamed poplar pulp after first stage impressafining; performing xylanase pretreatment on the pulp after the ultrasonic pretreatment; soaking the pulp in soda hydrogen dioxide solution after pretreatment; performing second stage impressafining after soaking; performing second stage soaking on the pulp in the soda hydrogen dioxide solution after the second stage impressafining; performing first stage refining on the pulp with the soaking liquid; performing high concentrated storage and bleaching after the first stage refining; and performing second stage refining to obtain high-brightness high-yield high-strength chemical mechanical pulp. The poplar ultrasonic chemical mechanical pulping technique can improve the mechanical pulping performance of fast-growing poplar, enlarge the application range of poplar high-yield pulp, improve the performance of poplar paper pulp, and improve the use value of the poplar.

The invention discloses a pulp making method for discharging sewage thoroughly which includes the following steps: pulping material, steam cooking agent and catalyst are mixed evenly and put into a spherical digester and the mixture is cooked by steam; the cooked material is squeezed by passing through a plurality of twin-screw extruders connected in series so as to extract black liquid and obtain the pulp material, and the black liquid obtained from the last twin-screw extruder is squeezed sequentially after returning to the former twin-screw extruder, while the black liquid obtained from a first and a second twin-screw extruders is merged straightly, and the merged black liquid is concentrated and dried to obtain alkali lignin and or lignosulfonate; the pulp material is delivered into a twin-screw rubbing and kneading pulper, the polyester washing is carried out in multiple-section series while the pulp is grinded, or the polyester washing is carried out in multiple-section series and bleached in multiple-section series, the washing water is returned to the washing process in the former section, and finally the residuary black liquid is obtained, that is the washing water coming from the first washing process; then, the residuary black liquid is returned to the pulping material or the spherical digester; the pulp material is refined in a dual-disk refining machine by adding water, then a pulp plate is made after the refined pulp material enters a paper machine. Meanwhile, the removed water circulates to the dual-disk refining machine or other processes needing the water by the pure water treatment.

The invention discloses a method for bleaching cashmere loose fiber. The method comprises the following steps of: A. pre-bleaching by using a mixed solution comprising 2.5 to 3.0 wt% of sodium chloride, 0.6 to 0.8 wt% of sodium carbonate, 0.15 to 0.2 wt% of penetrating agent and 0.15 to 0.2 wt% of degreasing agent; B. performing oxidation bleaching for the first time by using a mixed solution comprising 30 to 35 wt% of hydrogen peroxide, 7.5 to 8.75 wt% of oxygen bleaching stabilizer and 1.2 to 1.5 wt% of cashmere protective agent; C. performing oxidation bleaching for the second time by using a mixed solution comprising 25 to 30 wt% of hydrogen peroxide, 2 to 2.5 wt% of ammonia water, 2 to 2.5 wt% of sodium pyrophosphate and 1.2 to 1.5 wt% of cashmere protective agent; D. washing by using deionized water; E. neutralizing by using acid; and F. rinsing by using deionized water. By the method, the whiteness of the bleached cashmere is improved, the production cost is reduced and the production time is reduced.

The invention discloses a method for beaching shellac using chlorine dioxide and an alcohol solvent. The method comprises the following steps of: dissolving shellac using the alcohol solvent into solution, adding chlorine dioxide to the solution under the condition of constant temperature and stirring the solution for bleaching for certain time, thereby obtaining bleached shellac solution; adding dilute sulphuric acid to the bleached shellac solution so that the bleached shellac is separated out, and then repeatedly washing the bleached shellac until the pH of washing water is neutral; and drying the shellac at the room temperature, thus obtaining the bleached shellac, wherein the absorbance of the ethanol solution in the position of 490 nm can be reduced to 1.6% of the raw material shellac, while the color index thereof can be reduced to be less than 0.5#; and other technical indexes are capable of meeting the requirements of the refined bleached shellac level I. The method is characterized in that: bleaching conditions are mild; a non-alkaline condition is adopted; the bleaching temperature is low; the dosage of an acidic precipitator is low; the color index of the obtained bleached shellac is low; and accurate control and regulation can be performed by adjusting the dosage of the chlorine dioxide, etc; therefore, the application of the bleached shellac in special fields can be extended.

The invention discloses a linen fiber bleaching device for textile production and relates to the technical field of textile production. In order to solve the problem that the bleaching time is difficult to control and linen fibers are easy to damage when the linen fibers are soaked in a solution to be stirred, the linen fiber bleaching device specifically comprises a shell, a plurality of supporting frames are fixedly installed at the bottom of the shell, driving mechanisms are fixedly installed on the two sides of the top of the shell, a capping mechanism is fixedly installed between the topends of the two driving mechanisms, and bleaching sections extending downwards are arranged in the middle sections of the driving mechanisms. According to the linen fiber bleaching device for textileproduction, a bleaching solution is in contact with a heating mechanism when being sprayed out; the linen fibers are heated and cooked; the linen fiber bleaching efficiency is improved; the linen fibers are drained; a bleaching solution is recycled; the loss of the solution is reduced; the situation that the working environment is affected due to solution dripping is avoided; raw materials can becontinuously bleached due to the fact that the raw materials enter from one end and exit from the other end, and the linen fiber bleaching processing efficiency is improved.

The invention relates to a method for alkaline hydrogen peroxide bleaching of paper pulp. Chitosan with deacetylation degree bigger than 80% is added in the alkaline hydrogen peroxide bleaching process of high yield pulp or deinked pulp to act as the stabilizer of the hydrogen peroxide, and the dosage of the chitosan is 0.5-5kg per ton pulp; and hydrogen peroxide, sodium hydroxide and sodium silicate are added at the same time of bleaching. By adding chitosan in the alkaline hydrogen peroxide bleaching of the paper pulp, the method can improve the bleaching efficiency of the hydrogen peroxide and the whiteness of the paper pulp.

The invention discloses a zero discharge process of pulping waste liquid of all-cotton straw pulp. The process includes firstly performing front-end high concentration extraction of pulping waste liquid, then performing evaporation and concentration of the high concentration pulping waste liquid, recycling evaporation and condensation water, and recycling evaporation residue fluid, so as to realize the zero discharge of the pulping waste liquid finally. The front-end high concentration extraction of the pulping waste liquid includes cotton stalk raw material pigment decomposition, pigment extraction and reverse washing, and front-end extraction.

The invention provides a paper pulp high density bleaching method which comprises the following steps: condensing unleached paper pulp after washing and carrying out extruding dehydration on the condensed paper pulp with a double-screw extruder so as to obtain a high density slurry; pumping mixed liquor of hydrogen peroxide and a bleaching auxiliary agent into the high density slurry to obtain a mixture of materials and reagents; inputting the mixture into a high density bleaching warehouse with feeding spirals and carrying out bleaching at elevated temperature and pressure so as to obtain a bleached slurry; directly inputting the bleached slurry into a high density pulping machine with feeding spirals without washing, and adding sodium hydrosulphite into the high density pulping machine with metering screws during the process of feeding so as to obtain a mixture of materials and reagents; inputting the mixture into the high density bleaching warehouse with feeding spirals after the mixture comes out from the high density pulping machine, discharging the mixture after bleaching at elevated temperature and carrying out fiber dispersion and washing to obtain high beating degree bleaching paper pulp. According to the invention, slurries are delivered by spirals and concentration of the delivered slurries is high, which enables energy consumption in delivery to be reduced, heat energy consumption in the chemical reaction of bleaching to be effectively reduced and economic benefits to be increased.

The invention discloses a laser marking and bleaching device and a machining method thereof. The device comprises a laser, a beam expanding device, a galvanometer, a lens, a moving platform, a power detection device and an industrial personal computer, wherein the beam expanding device is arranged behind the laser; the galvanometer is arranged behind the beam expanding device; the lens is arranged behind the galvanometer; a workpiece is placed on the moving platform; the power detection device is used for detecting power of emitted light and feeds back measured data to the industrial personal computer; and the industrial personal computer is used for controlling marking and bleaching. Compared with the prior art, the laser marking and bleaching device and the machining method thereof have the beneficial effects as follows: marking and bleaching results are detected in real time and the difference and the trend relation between the marking and bleaching results and target results are analyzed in the marking process through power feedback, then the laser, the galvanometer and the moving platform are adjusted, and the marking and bleaching efficiency is greatly improved through the manner.

The invention discloses a bleaching method for bleaching deinked waste pulp. The bleaching method has the advantage of avoiding the environment pollution caused by the conventional bleaching using sodium hydrosulfite and thiourea dioxide. The method is an environment friendly reducibility bleaching method which has great improvement on the whiteness of the waste pulp and low cost. The method can overcome the defect of a yellow color system lying in the conventional bleaching through the sodium hydrosulfite. In addition, sulphate used in the method can selectively be sodium bisulphite or sodium pyrosulfite so as to further improve the whiteness after the waste pulp is bleached and reduce the dosage of sodium borohydride. A chelating agent is at least one of sodium silicate, disodium edta or tetrasodium salt, and diethylene triamine pentacetic acid or sodium tripolyphosphate. Additives and the dosage of the additives can be adjusted according to the actual metallic ion content in the waste pulp so as to improve the bleaching efficiency and reduce the cost of the bleaching medicine for unit whiteness improvement.

The invention discloses a horizontal kiering tank for kiering gauze. The horizontal kiering tank comprises a main cylinder body, an expanding cylinder, a preparation cylinder, a heat exchanger, a control panel and a water gauge device, wherein the main cylinder body is cylindrical, is horizontally arranged on a cylinder body bracket, is used for accommodating fabrics and rinsing solution, and is a place for carrying out a rinsing process; the expanding cylinder is arranged above the main cylinder body, and is used for reducing the pressure inside the main cylinder body; the preparation cylinder comprises a barrel, a water inlet, a water outlet, a stirring motor, a charging pump motor and a pressurizing opening, and is used for preparing a bleaching agent; the heat exchanger is used for heating tap water and introducing the tap water into the preparation cylinder; the control panel is used for setting programs and controlling operation of the kiering tank; and the water gauge device is used for monitoring the water level in the main cylinder body. According to the horizontal kiering tank, the kiering process and bleaching agent preparation are mechanized, the gauze bleaching efficiency is improved, and only one person is required for operation, so that the production time and labor cost can be reduced; and the main cylinder body is horizontally arranged, so that the height of a workshop can be reduced, and an operation platform is not required.

A reducing and bleaching composition for decoloured waste pulp is prepared from sodium dithionite (5-15 wt.%), chelating agent (1.25-15), sodium carbonate or sodium hydroxide or their mixture (0.25-3) and water (79.5-93.5) through uniform mixing. Its bleaching method features that the stabilizer and said composition are cooperated, and the oil or solvent not dissolved in water is added to isolate air, so improving the stability of bleaching liquid, reducing consumption of sodium dithionite and improving bleaching effect. Its advantages include less damage to strength and opaqueness of paper fibres, less corrosion to pipeline, less pollution and low cost.

The invention relates to a pretreatment technology before digital printing of high-count cotton fabric. Before digital printing, processes of singeing, ultrasonic boiling and bleaching, mercerizing, process of padding a slurry and preshaping are sequentially performed on gray fabric, and through formula optimization and technological optimization during boiling and bleaching as well as slurry padding, the fabric has a relatively good printing state before digital printing; the high-count cotton fabric treated by the pretreatment technology provided by the invention not only keeps smooth and soft surface properties of the high-count cotton and the like, but also is endowed with relatively high cleanliness, whiteness, dye affinity and the like, so that a guarantee is provided for high-precision digital printing, and the printed fabric is exquisite in pattern and high in color and luster.

The invention discloses a method for bleaching cotton fabrics with high whiteness effects. The method is characterized in that inorganic acid is used for treating cotton fabrics; inorganic salts and mineral matters which cause ineffective decomposition of hydrogen peroxide are removed; hydrogen peroxide is used for carrying out bleaching treatment; natural pigments in cotton fibers are removed, so that the cotton fabrics have high-whiteness bleaching effects and good strength.