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961.
CUI Huxiong CHENG Tiantao YU Xingn CHEN Jianmin XU Yongfu FANG Wen 《环境科学学报(英文版)》2009,21(8):1103-1107
The variations of sulfate formation and optical coe cients during SO2 heterogeneous reactions on hematite surface under di erent
SO2 concentrations were examined using in situ di use reflectance infrared Fourier transform spectroscopy (DRIFTS) and ion
chromatograph (IC). Laboratory experiments revealed that within ambient SO2 of 0.51–18.6 ppmv, sulfate product, producing velocity,
absorption and backward scattering coe cients showed an increasing trend with SO2 concentration. Under given SO2 concentration,
the velocity of sulfate producing performed an evolution of initial increasing, midterm decreasing and final stabilizing. The reactive
uptake and Brunauer-Emmett-Teller (BET) uptake coe cients of heterogeneous reactions rose with SO2 and exhibited high reactivities.
Considering global warming, this result is important for the knowledge of heterogeneous reactions of SO2 on mineral particle surface
in the atmosphere and the assessment of their impacts on radiative forcing. 相似文献
962.
考察了吸附在CMC(羧甲基纤维素纳)固定化烟曲霉活菌体小球中活性艳蓝KN-R和活性艳红K-2BP的解吸,并在此基础上提出了吸附-回收染料的技术思路。结果表明:pH值为12.0的75%乙醇对CMC固定化烟曲霉活菌体小球中的活性艳红K-2BP和活性艳蓝KN-R的解吸效果较好。30min内,对CMC固定化烟曲霉活菌体小球中的活性艳蓝KN-R和活性艳红K-2BP的解吸率分别为60.8%和50.4%。CMC固定化烟曲霉活菌体小球中的活性艳红K-2BP的解吸动力学符合一级指数衰减模型。CMC固定化烟曲霉活菌体小球能重复利用三次以上。 相似文献
963.
964.
预加好氧颗粒对SBR中好氧颗粒污泥形成的影响 总被引:3,自引:2,他引:1
以活性污泥曝气池中的絮状活性污泥为接种污泥,采用人工配制的模拟生活污水,通过观测颗粒形态和粒径的变化,研究预先加入15%成熟好氧颗粒污泥对好氧颗粒污泥形成过程的影响.对比研究发现,2个反应器内小颗粒(0 .1~0 .3 cm)的形成均较快,但大颗粒的形成速度相差明显.培养过程中还能明显观察到丝状菌缠绕和絮状污泥黏附在小颗粒表面.反应器启动第1、7、14 d,污泥平均体积粒径分别从0 .10、0 .16 cm上升到0 .23、0 .30 cm,最终达到0 .28、0 .43 cm.研究结果表明,预先加入15%成熟好氧颗粒污泥,能加速好氧颗粒污泥在反应器内形成. 相似文献
965.
966.
967.
A self-design bioreactor system employing a fixed bed operation process with immobilized Bacillus subtilis AYC beads for NH4
+-N
removal from slightly polluted water was proposed. Polyvinyl alcohol and Na-alginate were used as a gel matrix to entrap Bacillus
subtilis AYC to form the immobilized beads. The NH4
+-N removal process was studied in a intermittent operation mode to examine
the start-up and steady state behaviors of the immobilized AYC in the reactor. The results indicated that the reactor was in the start-up
state during the first week. NH4
+-N began to be steadily removal since the second week, and the nitrogen removal rate was between
84.61% and 96.19% when the hydraulic retention time (HRT) was 30 min. To apply Bacillus subtilis AYC to develop a practical
nitrogen removal system and further understand its nitrogen removal ability, the bioreactor was continuously operated under different
experimental perameters. The results showed that under the optimum conditions of an HRT of 20 min and DO of 3.77–5.80 mg/L,
the NH4
+-N removal rate reached 99.55%. The NH4
+-N removal rate increased as the C/N ratio increased. However, a high C/N may
cause a high residual carbon level in the effluent, therefore, the most suitable C/N ratio was 10. In addition, the results showed that
the bioreactor system could remove many types of nitrogen such as NH4
+-N, NO3??-N and organic-N, and had a good performance for
inorganic nitrogen removal from sewage. 相似文献
968.
969.
本实验采用先进的厌氧氨氧化(Anammox)颗粒污泥工艺对某酵母厂的二沉出水进行了毒性实验与连续流实验.毒性实验结果表明该类废水对Anammox细菌有一定的抑制作用,但没有影响最终的去除效果;而近一个半月的连续流实验数据则表明:在进水氨氮浓度300~360mg/1的情况下,污泥负荷与容积负荷可以稳定地上升,出水氨氮在50mg/l以下,亚硝酸盐氮维持在5mg/l左右,氨氮去除率可这80%以上. 相似文献
970.