INFLUENCE OF FINES ON FREE DRAINAGE OF WHEAT STRAW PULP
【摘要】：正Wheat straw pulp is one of most important non-wood raw materials for the pulp and paper industry in China. One of the biggest problems with non-wood fibers such as wheat straw in papermaking is their slow drainage, especially on the wire section of the paper machine. The behaviour of free drainage of the wheat straw pulp and the influence of fines in the pulp on drainage were investigated as part of a study on dewatering properties of wheat straw pulp. The results of this study show that the free drainage of wheat straw pulp is clearly slower than those of birch and pine pulps at the same beating degree. The fines fraction of wheat straw pulp has a significant influence on the drainage. Image analysis data indicate that the fines of wheat straw pulp are less ragged (less fibrillated) and with a bigger particle area and have more flake-shaped particles than the fines of birch and pine pulp. These are two important factors influencing the drainage process of wheat straw pulp. The differences in particle area and raggedness between pulps decrease with decreasing particle size. The free drainage rate can be unproved by removing fines fraction from wheat straw pulp or adding longer fiber pine pulp to the furnish.