共查询到20条相似文献,搜索用时 500 毫秒
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改性玉米秸秆吸附去除废水中四环素的研究 总被引:1,自引:0,他引:1
应用平衡吸附法,研究了不同投加量(改性玉米秸秆)、温度及pH条件下,改性玉米秸秆对水体中四环素的吸附作用,并利用等温曲线及吸附动力学方程对试验结果进行了拟合。结果表明:在吸附剂用量0.4g,温度30℃,振荡时间30min,pH值7的条件下,对水体中四环素浓度为50.136mg/L的吸附率可达93.4%。四环素废水吸附均符合Langmuir及Freundlich等温模式。但Langmuir方程拟合得较好,Elovich方程能更好地拟舍改性玉米秸秆对水体中四环素的吸附动力学曲线。 相似文献
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以茄子秸秆为原料,ZnCl2为活化剂制备粉末状活性炭,主要研究了活性炭对染料废水的吸附性能;以活性红X-3B和酸性蓝RL为模型染料,考察了染料初始浓度、pH值、活性炭投加量和吸附时间等对染料脱色率的影响。结果表明,染料初始浓度和活性炭投加量对染料脱色率影响较大。初始浓度为300mg/L时,活性炭的最佳投加量分别为1g/L和1.4g/L;在最佳工艺条件下,脱色率分别在93%和98%以上,COD去除率分别为94.5%和86.4%,出水水质达到国家一级《纺织染整工业水污染物排放标准》(GB 4287—1992)。 相似文献
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制备并研究了改性纤维素对Cu2 、Zn2 、Ni2 3种重金属离子的捕集效果.研究了反应时间、药剂用量、pH值、反应温度对其效果的影响.结果表明,在pH值为中性或碱性,反应温度为25℃时,改性纤维素对重金属离子具有较好的捕集效果.今后可进一步根据物质结构与性能的关系对天然高分子进行改性,并加强应用的研究. 相似文献
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Piggery waste treatment by anaerobic digestion and nutrient removal by ionic exchange 总被引:1,自引:0,他引:1
E. Snchez Z. Miln R. Borja P. Weiland X. Rodriguez 《Resources, Conservation and Recycling》1995,15(3-4)
Piggery wastes must be treated before their disposal. The high solids content and high chemical oxygen demand of piggery wastes indicated that anaerobic biological treatment could be successfully applied as primary treatment. For that reason, a comparison between upflow anaerobic sludge bed reactor (UASB) and anaerobic fixed bed reactor (AFBR) at a similar organic volumetric loading rate of 5 kg DQO/m3 day was carried out. 60% of the piggery waste COD was removed with the AFBR compared to 40% with the UASB, thus showing a better performance of the AFBR. After 1-h sedimentation secondary process, both anaerobic effluents were treated by ionic exchange with natural zeolite due to their high values of ammoniacal nitrogen (NH+4 plus free NH3). The high removal of nutrients reported (90%) shows zeolite to be a good choice as tertiary treatment. 相似文献
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K. R. Reddy P. D. Sacco D. A. Graetz K. L. Campbell L. R. Sinclair 《Environmental management》1982,6(3):261-271
Potential use of reservoirs and flooded fields stocked with aquatic plants for reduction of the nutrient levels of organic soil drainage water was evaluated. The treatment systems include 1) a large single reservoir (R1) stocked with waterhyacinth (Eichhornia crassipes), elodea (Egeria densa), and cattails (Typha sp.) in series; 2) three small reservoirs in series with waterhyacinth (R2), elodea (R3), and cattails (R4), grown in independent reservoirs; 3) a control reservoir (R5) with no cultivated plants; 4) a large single flooded field planted to cattails; 5) three small flooded fields in a series planted to cattails; and 6) a flooded field with no cultivated plants. Drainage water was pumped daily (6 hours a day, and 6 days a week) into these systems for a period of 27 months at predetermined constant flow rates. Water samples were collected at the inlet and outlet of each treatment system and analyzed for N and P forms.The series of reservoirs stocked with aquatic plants functioned effectively in the removal of N and P from agricultural drainage water, compared to a single large reservoir. Allowing the water to flow through the reservoir stocked with waterhyacinth plants with a residence time of 3.6 days was adequate to remove about 50% of the incoming inorganic N. Allowing the water to flow through a series of two small reservoirs, R2 and R3, with a residence time of 7.3 days was necessary to remove about 60% of the incoming ortho-P. Flooded fields were effective in the removal of inorganic N, but showed poor efficiency in the removal of ortho-P.Florida Agricultural Experiment Stations Journal Series No. 2320. 相似文献
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石油污染土壤中石油含量对玉米的影响 总被引:27,自引:1,他引:26
为了弄清石油污染土壤中石油类对农作物的影响,吉林油田进行了一年的田间玉米种植试验。在不同浓度水平,分别对玉米出苗率、可见外观特性、百粒重、产量和品质进行了较系统的观察、监测、类比分析。结果表明,土壤中石油含量的不同,对玉米生长过程各项指标有不同的影响。并找出吉林油田土壤—玉米系统中影响玉米生长及其产量的土壤临界含油量。 相似文献
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Monitoring the environment for a large list of organic compounds present at low levels is costly. The primary purpose of such monitoring is to assure that hazardous levels of such compounds are not released into, or present in, the environment. Viewing this as a quality control problem, we suggest that samples from different sources can be composited using group testing procedures prior to analysis. Our purpose is to describe the basic concepts and suggest problems requiring study. 相似文献
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Hyperfiltration and nanofiltration membranes were tested with different water matrices for the removal of excess fluoride
from underground water. Initially, the experiments were done with synthetic samples prepared by adding known amounts of sodium
fluoride and calcium chloride in distilled water. The effect of feed water composition, pH, temperature of feed water, operating
pressure, and feed water flow rate on separation efficiency of both types of membrane was studied by varying one parameter
at a time and keeping all other parameters constant. Thus, the optimum operating conditions for the process were determined
and after that ground water samples collected from three villages of district Gurgaon, Haryana, India (Farukhnagar, Wazirpur,
and Mevka) were treated under optimum operational conditions. The mass transfer coefficient and membrane parameters were estimated
for each data point using two-parameter model (Film theory and Solution-diffusion model) to study the concentration polarization
on membrane surface. The nanofiltration membrane showed high percentage rejection of bivalent ions when compared to monovalent
ions in a binary system. But in multicomponent system, when fluoride and calcium coexisted, the removal of fluoride was comparable
to calcium removal because of the low solubility product of calcium fluoride. The results with RO membrane revealed that it
removes practically all the ions present in water at high pressure, which need to be passed through a lime column to remineralize
the water, to make it suitable for drinking purposes, whereas by running the system at low pressure which will further reduce
the cost of operation, rejection percentage goes down to get permeate of required quality. 相似文献