THE CREATION AND IMPLEMENTATION OF THE RESOURCE-CONSERVING TECHNOLOGY OF PAPER AND PAPERBOARD SIZING WITH HYDRO-DISPERSIONS OF MODIFIED ROSIN IN THE MODE OF HETERO-ADAGULATION OF PEPTIZED PARTICLES
The specific features of the application of hydro-dispersions of modified rosin (HDMR) in dispersed systems have been studied, and the technological mode of hydrophobicity rise, paper and cardboard strength increase has been developed. It has been shown the necessity of controlling the processes of MRH electrolyte coagulation and peptization of coagulants by changing the content of a particular type of aluminum hydroxide compounds (Al(H2O)63+, Al(H2O)5(OH)2+, Al(H2O)4(OH)2+, Al(H2O)3(OH)30 и Al(H2O)2(OH)4-). The proposed new technological method allows obtaining new sizing complexes in the form of fine-dispersed (size 180-220 nm) positively charged particles (charge from +22 to +30 mV) of peptized particles. Such particles are able to be uniformly distributed by a monolayer and firmly fixed on the surface of negatively charged cellulose fibers, which facilitates the process of hydrophobization in a more efficient mode of heteroadagulation. This effect is achieved due to the peptization (disaggregation) of electrically neutral coagulates (size not exceeding 1800 nm) formed in the first coagulation zone of the HDMR, while according to the existing technology, the role of sizing complexes is performed by electrically neutral coagulates (size 2000-3800 nm and more) formed in the second area of HDMR coagulation. The developed technology to ensure the peptization coagulates formed in the first area of rapid coagulation of neutral and high-resin HDMR, enables to obtain new sizing systems in the form of finely-dispersed positively charged peptized particles. Hexa aqua aluminium ions Al(H2O)63+ havea peptizing effect on the coagulates. The structure of peptized particles differs from that of coagulums in the content of ions Al(H2O)63+, Al(H2O)5(OH)2+, Al(H2O)4(OH)2+ и SО42- in the adsorption and diffusion layers. The implementation of the developed resource-saving technology at five paper and paperboard enterprises confirmed the results of the research and demonstrates the feasibility of economy in the production of each ton of paper and cardboard up to 30-40% of hydro-dispersion of modified rosin and reduce the electrolyte consumption by 1.5-2.0 times.