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851.
Dou Junfeng Luo Guyuan Liu Xiang 《Frontiers of Environmental Science & Engineering in China》2007,1(2):233-239
Enhanced biological phosphorus removal (EBPR) is a commonly used and sustainable method for phosphorus removal from wastewater.
Poly-β-hydroxybutyrate (PHB), polyphosphate, and glycogen are three kinds of intracellular storage polymers in phosphorus accumulation
organisms. The variation of these polymers under different conditions has an apparent influence on anaerobic phosphorus release,
which is very important for controlling the performance of EBPR. To obtain the mechanism and kinetic character of anaerobic
phosphorus release, a series of batch experiments were performed using the excessively aerated sludge from the aerobic unit
of the biological phosphorus removal system in this study. The results showed that the volatile suspended solid (VSS) had
an increasing trend, while the mixed liquid suspended sludge (MLSS) and ashes were reduced during the anaerobic phosphorus
release process. The interruption of anaerobic HAc-uptake and phosphorus-release occurs when the glycogen in the phosphorus-accumulating-organisms
is exhausted. Under the condition of lower initial HAc-COD, HAc became the limiting factor after some time for anaerobic HAc
uptake. Under the condition of higher initial HAc-COD, HAc uptake was stopped because of the depletion of glycogen in the
microorganisms. The mean ratio of Δρ
P/Δρ
PHB, Δρ
GLY/Δρ
PHB, Δρ
P/ΔCOD, was 0.48, 0.50, 0.44, and 0.92, respectively, which was nearly the same as the theoretical value. The calibrated kinetic
parameters of the HAc-uptake and phosphorus-release model were evaluated as follows: Q
HAc,max was 164 mg/(g · h), Q
P,max was 69.9 mg/(g · h), K
gly was 0.005, and KCOD was 3 mg/L. An apparently linear correlation was observed between the ratio of Δρ
P/ΔCOD and pH of the solution, and the equation between them was obtained in this study.
Translated from Acta Scientiae Circumstantiae, 2005, 25(9), 1164–1169 [译自: 环境科学学报] 相似文献
852.
介绍德兴铜矿选矿厂大型石灰料仓在汽车卸料时产生的大量石灰粉尘的收集、净化处理方式及袋式除尘器主要性能参数的确定。 相似文献
853.
评价甲基环戊二烯基三羰基锰(MMT)抗爆剂 总被引:4,自引:0,他引:4
评述了抗爆剂甲基环戊二烯基三羰基锰(MMT)研究和应用的最新进展。MMT的合成工艺简单,抗爆能力优良,燃烧沉积物易于清除,不会堵塞尾气催化净化剂,毒性较小,环境安全性高,可替代四乙基铅作为抗爆剂。 相似文献
854.
855.
重庆南山酸雨与马尾松衰亡的关系 总被引:17,自引:2,他引:17
1985—1986年对重庆南山马尾松林衰亡与酸雨的关系进行了研究。四个月的雨水监测表明南山酸雨况情严重。酸雨频率百分之百,平均pH4.2—4.4,最低pH3.6—4.0。土壤酸化程度较重(pH3.7—4.0)。土壤酸化的主要原因是酸雨的输入。濒死树针叶中锰和钴元素大为减少,与土壤中这两种元素的减少相对应。濒死树针叶中铝大量积累,土壤中活性铝增多和铝钙比增大。初步肯定酸雨是南山马尾松衰亡的重要原因之一。 相似文献
856.
Luo Weiguo Wang Shihe Huang Juan Yan Lu Huang Jun 《Frontiers of Environmental Science & Engineering in China》2007,1(3):316-319
To determine the impact of photosynthesis and transpiration on nitrogen removal in wetlands, an artificial wetland planted
with reeds was constructed to treat highly concentrated domestic wastewater. Under different meteorological and hydraulic
conditions, the daily changes of photosynthesis and transpiration of reeds, as well as nitrogen removal efficiency were measured.
It was found that net photosynthesis rate per unit leaf area was maintained on a high level (average 19.0 μmol CO2/(m2·s)) from 10:00 to 14:00 in July 2004 and reached a peak of 21.1 μmol CO2/(m2·s) when Photon Flux Density was high during the day. Meanwhile, TN and NH4
+-N removal efficiency rose to 79.6% and 89.6%, respectively—the maximum values observed in the test. Correlation coefficient
analysis demonstrated a positive correlation among photon flux density, net photosynthetic rate, transpiration rate, and TN
and NH4
+-N removal efficiency. In contrast, there was a negative correlation between stomatal conductance and TN and NH4
+-N removal efficiency. Results suggest that the photosynthesis and transpiration of wetland plants have a great impact on
nitrogen removal efficiency of wetlands, which can be enhanced by an increase in the photosynthesis and transpiration rate.
In addition, the efficiency of water usage by reeds and nitrogen removal efficiency could be affected by the water level in
wetlands; a higher level boosts nitrogen removal efficiency.
Translated from China Environmental Science, 2006, 26(1): 30–33 [译自: 中国环境科学] 相似文献
857.
水解酸化——生物接触氧化处理合成橡胶废水研究 总被引:8,自引:0,他引:8
采用水解酸化-生物接触氧化相结合的处理工艺处理合成橡胶废水,结果表明,在进水CODcr和BOD5分别656mg/L和286mg/L的情况下,出水平均值分别为82mg/L和28.6mg/L平均去除率分别达到87.5%和90%,水解酸化可将民橡胶废水的可生化性同0.44提高至0.56。 相似文献
858.
Vertical flow constructed wetlands is a typical ecological sanitation system for sewage treatment.The removal rates COD,BOD5,SS,TN and TP were 60%,80%,74%,49%and 79%,respectively,when septic tank effluent was treated by vertical flow filter.So the concentration of COD and BOD5 in the treated effluent could meet the quality standard for irrigation water.After that the treated effluent was used for hydroponic cultivation of water spinach and romaine lettuce,the removal efficiencies of the whole system for COD, BOD5,SS, TN and Tpwere 71.4%,97.5%,96.9%,86.3%,and 87.4%,respectively.And it could meet the integrated wastewater discharge standard for secondary biological treatment plant.It was found that using treated effluent for hydroponic cultivation of vegetables could reduce the nitrate content in vegetables.The removal rates for total bacteria and coliform index by using vertical flow bed system with cinder substrate were 80%-90% and 85%-96%,respectively. 相似文献
859.
860.