Low-temperature precausticizing — a hopeful approach for green liquor desilication, TAPPI JOURNAL February 2017
ABSTRACT: We investigated silica removal by low-temperature precausticizing and the properties of second causticizing calcium carbonate (CCC). The results showed that about 89.3% of silica removal was achieved when 20% (the stoichiometric ratio) of causticizing quicklime was added for precausticizing at 20ºC for 60 min. After that, silica removal became slow. When no precausticizing quicklime was used to remove silica, the CCC particles had a rhombohedral crystal structure covered with amorphous material. As precausticizing quicklime was increased to 30%, the amorphous material and the crack disappeared, and the specific surface area decreased significantly. When CCC was used as filler, the Cobb value decreased significantly, and the sizing effect improved as precausticizing quicklime increased.
Application: Understanding the properties of CCC with different quicklime contents for low-temperature pre-causticizing, and its effect on paper quality, can mitigate the issues caused by “silica influence” and enable papermakers to reuse CCC produced from the chemical recovery process of wheat straw soda pulping.
TAPPI conference proceedings and presentations, technical papers, and publication articles provide technical and management data and solutions on topics covering the Pulp, Paper, Tissue, Corrugated Packaging, Flexible Packaging, Nanotechnology and Converting Industries.
Simply select the quantity, add to your cart and your conference paper, presentation or article will be available for immediate download.