【作者】 张中满；

【导师】 张晓昱；

【作者基本信息】 华中科技大学 ， 微生物学， 2007， 硕士

【摘要】 造纸黑液是一种高pH值、高COD、高木素含量的难降解废水,是造纸工业废水的主要来源,占造纸废水污染总量的90%以上。目前,对以草浆为主要制浆原料所产生的黑液,还没有一个既经济又有效的处理方法。本论文通过筛选得到产酸很强的褐腐菌菌株S和白腐菌菌株509-112,509-118。三株产酸菌经PDY培养可以使体系pH值由pH 7调节到pH 2左右,通过继续培养并进行转种其产酸性能仍能保持,可以调节pH值到pH 3以下,体现出三株菌株具有较强的产酸性能。将三株产酸菌应用于黑液的生物酸析处理,在灭菌的黑液体系中,只有褐腐菌菌株S保持较强的产酸性能,可以使pH值调节到3左右,菌株509-112,509-118的产酸性能受到抑制。经菌株S处理黑液,其COD和色度去除率分别可以达到60%和80%以上,可以确定菌株S是处理黑液的优势菌株。在不灭菌环境下连续处理黑液,发现接种量对菌株S产酸影响不大。在初始pH 7到pH 9的范围内,菌株S都可以连续稳定地使体系的pH值调节到4.5左右,可以对黑液进行酸析处理,但初始pH 10的环境下,其处理的稳定性下降。随着初始pH的升高,其处理黑液的周期延长。在黑液配比为1:2.5时,菌株S的产酸性能受到很大抑制,不能用于酸析处理黑液。较高的营养物浓度对菌株S产酸有利。在底部微氧曝气,温度在25℃条件下,对菌株S连续处理黑液工艺进行了研究,发现菌株S经驯化后,可以在开放环境下连续对黑液进行酸析处理,可以适应一定的高pH和COD浓度。经驯化4-5个批次后,菌株S可以逐步适应pH 11左右的高碱性环境进行产酸酸析处理黑液。高COD对菌株S连续处理黑液有抑制作用。通过驯化后,菌株S可以在此工艺中连续处理pH 10、COD负荷为45000mg/L的黑液,3天后,处理后出水pH为4.5左右、COD负荷为23038.36mg/L,木质素去除率为55.46%,色度去除率56.28%。利用菌株S处理混合废水表明,菌株S可以在灭菌情况下有效处理黑液和红薯混合废水,COD去除率可以达到75%左右。但菌株S不能利用黑液和肌苷混合废水以及不能在开放环境下处理黑液和红薯混合废水。更多还原

【Abstract】 Black liquor of alkali papermaking is a kind of refractory wastewater with high pH value, high COD and high concentration of lignin, which is the primary source of the wastewater from paper mills, accounting for more than 90% of total wastewater. At present, there still was not an effective and economical way to treat the black liquor derived from pulping using straw pulp as the main material.In this paper, three acid-producing strains, brown rot fungus strain S, white rot fungi 509-112 and 509-118, were obtained. The pH value could be adjusted from 7 to 2 in PDY medium using the three fungi. The acid-producing characteristics of these fungi could be maintained after continuous culturing and transferring, and they could adjust the pH value to below 3. These results showed that these fungi had high acid-producing capability.The biological acidation precipitation of black liquor treated by these fungi showed that only the strain S, maintaining the acid-producing capability, could decline the pH value to about 3 and acid-producing capability of the other two fungi was restrained in sterilized black liquor system. Furthermore, the removal rates of COD and Color in black liquor system could reach up to 60% and 80% after treating by strain S, and the strain S was screened as the predominant strain to treat black liquor. The paper also showed that inoculum had less influence on acid-producing capability of strain S in black liquor system which was not sterilized. When the initial pH ranging from 7 to 9 in medium, the strain S could adjust the pH value to around 4.5, however, the media could deeply influence the stabilization of acid-producing capability of strain S when the pH was 10. In addition, the treatment cycles would be prolonged in culture media with higher pH. The strain S could not treat the black liquor in media with black liquor (1:2.5), which attributed to acid production of the strain S was deeply restrained. Nutriment with high concentration was beneficial for acid production.The continuous treatment of black liquor by strain S with microaerobic aeration in open environment at 25℃was investigated. The results showed that the acclimated strain S could treat the black liquor effectively in the special equipment and adapt high pH value and COD. Furthermore, after acclimating for 4-5 times, the stains could treat the black liquor with pH 11. However, the acid-producing capability of strain S was inhabited by high COD deeply. In the special treatment equipment for black liquor, the strain S could treat the black liquor with pH 10 and COD 45000mg/L, the pH could be adjusted to 4.5, COD decreased to 23038.36mg/L, removal rates of lignin and color could be up 55.46% and 56.28% respectively after 3 days treatment.The treatment of mixed wastewater by strain S showed that the strain S could treat wastewater with black liquor and sweet potato starch process wastewater effectively in sterilized environment, the COD removal rate was 75%, however, the strain S could not treat the black liquor and inosine wastewater and the wastewater with black liquor and sweet potato starch process wastewater could be treated in the open environment.更多还原