稻草的氧碱法制浆(5)——对循环制浆过程黑液的评价

Alkali Oxygen Pulping of Rice Straw(5) Evaluation of Black Liquor Recycling in the Pulping Process

稻草的黑液循环氧碱法制浆在保证获得稳定的制浆质量的前提下，可使碱浸渍黑液和氧气蒸煮黑液的固含量分别提高到１６％和１１％左右，且氧气蒸煮黑液可省去脱硅处理。

In the alkali oxygen pulping of rice straw, concentrated black liquor from a previous cook is recycled and reused. Such a recycling of the black liquor is favorable to higher solid contents in the resultant black liquor, without any negative effects on pulp quality. At 16% increase in solid has been claimed for the alkali stage black liquor, and 11% for the oxygen stage black liquor. Furthermore,SiO2 content in the oxygen stage black liquor has been found to be as low as 0.4g/L and less, eliminating any necessity of the oxygen stage black liquor desilication. Such a practice of recycling part of the concentrated black liquor(in place of fresh water or dilute black liquor) for digestion can be circulated continually with no limitations. Heat conservation and water savings are being claimed. It also follows that pollution discharges are minimized.