Patent EA-000264-B1 (EA)
Title: Method and apparatus for continuously preparing cellulose pulp
Inventor: COMBETTE PHILIPPE
IPC: D21B1/12
Filed: 1996-11-18
Abstract: 1. A method for continuously preparing cellulose pulp, in particular for use in the chemical or paper industry, from a raw material consisting of textile fibres, characterized in that: separating the textile fibres from foreign matter, such as agricultural residues, metal or mineral particles; realizing densification of the textile fibers; continuously leaching and pre-cutting the textile fibres in a first processing machine (10)with two co-rotating screws(11, 12) to give a pulp with a dryness value of 25-40%; continuously leaching in a first dwell vessel (35), of latent period wherein the dwell time is of 30 to 60 minutes; continuously washing and bleaching the pulp in a second processing machine (40) with two co-rotative screws (41, 42) to give a pulp with a dryness value of 25-40%; continuously bleaching in a second dwell vessel (61), of latent period the dwell time is of 60 to 120 minutes.; diluting the pulp in a first dilution tank (62) to give the pulp with a concentration of value 1.5-3%; draining and pressing the cellulose pulp at the outlet of the first dilution tank (62) to give a pulp with a dryness value of 30-35%. 2. A method of Claim 1 characterized in that after draining and pressing the cellulose pulp at the outlet of the first dilution tank (62) and dilution is continued in the second dilution tank to give the pulp concentration with a value of 3 to 5%. 3. A method of Claim 2 characterized in that after second diluting the pulp is conveyed for storing in a reservoir, provided with an agitating means. 4. A method of Claim 1 characterized in that the first processing machine (10) comprises continuous and close to each other steps of the material transfer respectfully: step A of feeding said machine with textile fibres and mixing the textile fibres with water, injected into the machine at the beginning of this step; step B of compression; a primary step C of mixing and cutting; step D of conveying and treatment introducing at the beginning of the step leaching reagents and diluting water wherein the leaching reagents represent essentially a solution of caustic soda, consumption of which comprises a value of 2 to 5% of product reactivity in respect to the initial products; a second step of mixing and cutting; and a final step F of transporting and evacuation of the cellulose pulp into first dwell vessel (35) of the latent period. 5. A method of Claim 4 characterized in that water injected into the first processing machine (10) at the beginning of step A represents the water collected at draining and pressing the cellulose pulp and clear water. 6. A method of Claim 4 characterized in that at the end of step B compression recuperation of liquid residues is carried out. 7. A method of Claim 4 characterized in that between the outlet of the first processing machine (10) and the first dwell vessel (35) of latent period the cellulose pulp is maintained at a temperature, corresponding the temperature at the outlet from the first processing machine (10). 8. A method of Claim 1 characterized in that the second processing machine (40) comprises continuous and close to each other the steps of the material transfer respectfully: step G of feeding the bleached pulp fed from the first dwell vessel (35) of latent period and mixing this pulp with water, injected into this vessel at the beginning of this phase G; succession of steps H1, H2, H3 and H4 of compression, cutting and processing of the cellulose pulp; and step J of transportation and evacuation of the pulp into the second dwell vessel (61) of latent period. 9. A method of Claim 8 characterized in that water injected into the second processing machine (40) at the beginning of phase G represents the water collected at draining and pressing the cellulose pulp and clear water not earlier used in the technological process of pulp preparation. 10. A method of Claim 8 characterized in that the first H1 step of compression, cutting and treatment of the cellulose pulp comprises on one hand the first H11 step of compression and evacuation of liquid residues at the end of this phase and on the other hand the second step H12 of the pulp cutting. 11. A method of Claim 8 characterized in that the second H2 step of compression, cutting and treatment of the cellulose pulp comprises on one hand the H21 step of compression and introduction of the diluting water at the beginning of this phase and evacuation of liquid residues at the end of this phase and on the other hand the H22 step of cutting. 12. A method of Claim 8 characterized in that the third H3 step of compression, cutting and treatment of the cellulose pulp comprises on one hand the H31 step of compression and introduction of the diluting water at the beginning of this phase and evacuation of liquid residues at the end of this step and on the other hand the H32 step of cutting. 13. A method of Claim 8 characterized in that the fourth H4 step of compression, cutting and treatment of the cellulose pulp comprises on one hand the H41 step of compression with simultaneous introduction of the diluting water, solution of caustic soda the consumption of which correspondents to a value of 0.5 to 2% of reactive material in respect to the initial material, and solution of hydrogen peroxide he consumption of which correspondents to a value of 2 to 6% of reactive material in respect to the initial material and on the other hand the consumption of which correspondents a value of 0.5 to 2% of reactive material in respect to the initial material, the H42 step of cutting. 14. A method of Claim 1 characterized in that clear water is fed into each dilution tank (62, 69). 15. Apparatus for continuously preparing cellulose pulp in particular for use in the chemical or paper industry, from a raw material consisting of textile fibres, characterized in that: pneumatic means (2, 7) for conveying the textile fiberes; means of separating the textile fibres from foreign matter, such as agricultural residues, metal or mineral particles; a textile fibre densifier (6); means (8, 9) for extracting and filtering dust-laden air from the pneumatic means (2, 7) for conveying the textile fibres; a first processing machine (10) with two co-rotating screws (11, 12) for continuously leaching and pre-cutting the textile fibres to give a pulp with a dryness value of 25-40%; means (34) for conveying the cellulose pulp at a temperature, corresponding to its temperature at the outlet from the first processing machine (10); a first dwell vessel (35), of latent period for continuously leaching of the pulp, the dwell time of 30-60 minutes a second processing machine (40) with two co-rotative screws (41, 42) for continuously washing and bleaching the pulp to give a pulp with a dryness value of 25-40%; means (60) for conveying washed and bleached the cellulose pulp; a second first dwell vessel (61), of latent period for continuously leaching of the pulp, the dwell time of 60-120 minutes; a first dilution tank (62) with an agitator to give a pulp with a concentration value of 1.5-3%; a screw press (66) for draining and pressing the cellulose pulp o give a pulp with a dryness value of 30-35%; 16. Apparatus of Claim 15 wherein comprising after the screw press a second dilution tank with an agitator to give a pulp with a concentration value of 3-5%. 17. Apparatus of Claim 16 wherein comprising after the second dilution tank a storing tank with an agitator. 18. Apparatus of Claim 15 wherein the first processing machine (10) comprises continuous and close to each other steps of the material transfer respectfully: step A of feeding said machine with textile fibres and mixing the textile fibres with water, injected into the machine at the beginning of this phase; step B of compression with recuperation of liquid residues at the end of this steps; a primary step C of mixing and cutting; step D of conveying and processing, and introducing at the beginning of the step leaching reagents and diluting water wherein the leaching reagents represent essentially a solution of caustic soda, consumption of which comprises a value of 2 to 5% of product reactivity in respect to the initial products; a second step of mixing and cutting; and a final step F of transporting and evacuation of the cellulose pulp into first dwell vessel (35) of the latent period. 19. Process of Claim 18 wherein the water injected into the first processing machine (10) at the beginning of phase A represents the water collected at the outlet of the screw press (66) and clear water. 20. Process of Claim 15 wherein the second processing machine (40) comprises continuous and close to each other the steps of the material transfer respectfully: step G of feeding the bleached pulp fed from the first dwell vessel (35) of latent period and mixing this pulp with water, injected into this vessel at the beginning of this step; succession. of steps H1, H2, H3 and H4 of compression, cutting and processing of the cellulose pulp; and step J of transportation and evacuation of the pulp into the second dwell vessel (61) of latent period. 21. Apparatus of Claim 20 wherein the water injected into the second processing machine (10) at the beginning of step G represents the water collected at the screw press (66) and clear water. 22. Apparatus of Claim 20 wherein the first H1 step of compression, cutting and treatment of the cellulose pulp comprises the first H11 step of compression and evacuation of liquid residues at the end of this step and the second step H12 of the pulp cutting. 23. Apparatus of Claim 20 wherein the second H2 step of compression, cutting and treatment of the cellulose pulp comprises on one hand the H21 step of compression and introduction of the diluting water at the beginning of this step and evacuation of liquid residues at the end of this step and on the other hand the H22 step of cutting. 24. Apparatus of Claim 20 wherein the third H3 step of compression, cutting and treatment of the cellulose pulp com