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111.
生物工程处理草浆造纸废水系统的特点   总被引:8,自引:1,他引:7  
文章通过对许昌造纸厂废水处理系统的论述 ,介绍了以生化为主的碱法草浆造纸废水治理成套技术的概况、工艺流程、投资概算和运行成本等 ,并进一步阐明了这套技术的科学性、实用性和先进性  相似文献   
112.
Climate change and sea‐level rise will have severe impacts on coastal water resources around the world. However, whereas the influence of marine inundation is well documented in the literature, the impact of groundwater inundation on coastal communities is not well known. Here, core analysis, groundwater monitoring, and ground penetrating radar are utilized to assess the groundwater regime of the surficial aquifer on Bogue Banks Barrier Island (USA). Then, geospatial techniques are used to assess the relative roles and extents of groundwater and marine inundation on the dune‐dominated barrier island under sea‐level rise scenarios of 0.2, 0.5, and 1.0 m above current conditions by 2100. Additionally, the effects of rising water tables on onsite wastewater treatment systems (OWTS) are modelled using the projected sea‐level rise scenarios. The results indicate that the surficial aquifer comprising fine to medium sands responds quickly to precipitation. Water‐level measurements reveal varying thicknesses of the vadose zone (>3 to 0 m) and several groundwater mounds with radial flow patterns. Results from projected sea‐level rise scenarios suggest that owing to aquifer properties and morphology of the island, groundwater inundation may occur at the same rate as marine inundation. Furthermore, the area inundated by groundwater may be as significant as that affected by marine inundation. The results also show that the proportion of land in the study area where OWTS may be perpetually compromised by rising water tables under worst case scenarios may range from ~43 to ~54% over an 86‐year‐period. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
113.
研究了人工湿地循环处理哈氏仿对虾(Parapenaeopsis hardwickii)高盐度(21.1-23.3)养殖废水的净化效果。人工湿地对高盐度养殖废水中各水质指标去除率为:总氨氮66.7%,亚硝酸盐80.0%,化学需氧量12.5%,浊度69.1%,硝酸盐-12.1%,总氮3.5%,总磷0.0%。养殖池水质状况良好。在试验负载范围内,湿地对总氨氮、亚硝酸盐、浊度的去除量随进水污染负载量的增加而增加。研究表明:人工湿地能持续有效降低哈氏仿对虾养殖废水中的主要水质因子浓度。  相似文献   
114.
This study established wetland microcosms that were either unplanted or planted in monoculture with native mangrove species in Taiwan (Avicennia marina, Rhizophora stylosa, and Lumnitzera racemosa) for the purpose of receiving high-salinity mariculture effluents; additionally, the microcosms operated at different hydraulic retention times (HRTs). Plant growth and the performance of the microcosms with respect to pollutant removal were investigated. The results showed that seedlings of all three mangrove species survived and grew sufficiently well under continuous flooding. The presence of mangroves consistently improved SS, BOD5, and TP removal, particularly under short HRT conditions. The mangrove microcosms removed pollutants from the mariculture effluents with efficiencies of 5.7-27.1% (SS), 4.9-36.3% (BOD5), 18.7-29.9% (TP), 21.2-49.8% (NH4-N), and 5.4-37.7% (NOx-N). A. marina and L. racemosa were more tolerant of continuous flooding than R. stylosa. However, no species displayed consistently superior performance in decreasing all pollutant-related parameters investigated. For all pollutants, microcosms operating at a 2-d HRT exhibited a higher removal efficiency than those operating at a 0.5-d HRT.  相似文献   
115.
This study presents the influence of the addition of additives such as activated carbon, carbon tetra chloride, hydrogen peroxide, and potassium dichromate on ultrasonic reduction of pharmaceutical wastewater chemical oxygen demand (COD) under laboratory conditions. The addition of activated carbon increased the % COD reduction whereas the combined addition of activated carbon and H2O2/CCl4/K2Cr2O7 was found to show higher reduction. Among the various combinations investigated, the combined addition of activated carbon and CCl4 was found to be the best combination. However, the environmental and health problems associated with these chemicals limit the applicability of the process in an industrial level. Further investigation with this system showed that the initial pH and initial COD have significant influence on the removal rate. The data obtained were fitted with first order and Langmuir–Hinshelwood kinetic models. The values of the rate constants obtained indicated that the pharmaceutical wastewater can be treated efficiently by the proposed methods.  相似文献   
116.
我国造纸业废水中的污染因子危及地下水水质安全,通过对野外实地勘察和地下水取样的过程及结果进行分析研究,各地下水取样点的水质均符合国家饮用水卫生标准.用B·M舍斯塔科夫公式计算浸没过程,洪水时期地下水水位升高,研究区废水不会造成地下水的污染.  相似文献   
117.
Turbulence is defined as an eddy-like state of fluid motion where the inertial-vortex forces of the eddies are larger than any of the other forces that tend to damp the eddies out. Energy cascades of irrotational flows from large scales to small are non-turbulent, even if they supply energy to turbulence. Turbulent flows are rotational and cascade from small scales to large, with feedback. Viscous forces limit the smallest turbulent eddy size to the Kolmogorov scale. In stratified fluids, buoyancy forces limit large vertical overturns to the Ozmidov scale and convert the largest turbulent eddies into a unique class of saturated, non-propagating, internal waves, termed fossil-vorticity-turbulence. These waves have the same energy but different properties and spectral forms than the original turbulence patch. The Gibson (1980, 1986) theory of fossil turbulence applies universal similarity theories of turbulence and turbulent mixing to the vertical evolution of an isolated patch of turbulence in a stratified fluid as its growth is constrained and fossilized by buoyancy forces. Quantitative hydrodynamic-phase-diagrams (HPDs) from the theory are used to classify microstructure patches according to their hydrodynamic states. When analyzed in HPD space, previously published oceanic datasets showed their dominant microstructure patches are fossilized at large scales in all layers. Laboratory and field measurements suggested phytoplankton species with different swimming abilities adjust their growth strategies by pattern recognition of tur-bulence-fossil-turbulence dissipation and persistence times that predict survival-relevant surface layer sea changes. New data collected near a Honolulu waste-water outfall showed the small-to-large evolution of oceanic turbulence microstructure from active to fossil states, and revealed the ability of fossil-density-turbulence patches to absorb, and vertically radiate, internal wave energy, information, and enhanced turbulent-mixing-rates toward the sea surface so that the submerged waste-field could be detected from a space satellite (Bondur and Filatov, 2003).  相似文献   
118.
微藻处理养殖尾水已成为热点研究方向,有关一定盐度范围内海水养殖尾水的微藻处理研究较少。本试验调配了两种盐度(16和26)的海水养殖尾水,以空白组作对照,设置小球藻(Chlorella salina)初始接种密度梯度(5×105、1×106、2×106和3×106个/mL),研究小球藻对海水养殖尾水中不同形态氮和磷的去除效果。结果表明,小球藻在海水养殖尾水中生长良好,可有效去除尾水中的氮磷营养盐,16盐度组中各初始藻密度组对NH4+、NO3-和总溶解态氮(total dissolved nitrogen,TDN)的去除率分别为85.03%~85.87%、60.87%~63.70%和54.53%~57.64%,组间无显著差异(P>0.05);26盐度组中除5×105组外,其余藻密度组对NH4+、NO3-和TDN的去除率分别为87.23%~88.16%、56.70%~57.79%和53.31%~54.62%,且组间无显著差异(P>0.05),表明小球藻初始接种密度对尾水中氮盐的去除无显著影响。除5×105个/mL组外,16与26盐度组中对TDN的去除率无显著差异,表明盐度变化对氮的去除无影响。随着初始藻密度的升高,16和26处理组对总溶解态磷(total dissolved phosphorus,TDP)的去除率均上升,分别为76.13%~99.53%和63.72%~96.83%,表明藻初始接种密度的升高可促进尾水中磷的去除,且盐度升高没有影响小球藻对磷的去除。本研究获得了不同初始接种密度小球藻对一定盐度范围的海水养殖尾水的吸收利用特点,可为海水养殖尾水的生态化处理提供一定的理论基础。  相似文献   
119.
This experimental research deals with using steel scrap as a heterogeneous catalyst. This catalyzes the oxidation reaction of real textile dye wastewater based on a modified solar photo‐Fenton oxidation process. Morphologic analysis and mapping of the elementary composition of the steel scrap have been carried out by scanning electron microscopy. The effects of concentration of H2O2, the pH of the solution and the catalyst loading on the degradation of textile dye wastewater are elucidated. Kinetic studies have been performed for the decolorization of wastewater under optimum conditions. It could be concluded that the steel scrap is a potential substitute for ferrous salts as a catalyst for the solar photo‐Fenton reaction.  相似文献   
120.
金川矿区尾矿库排水对地下水水质影响:现状及预测分析   总被引:1,自引:0,他引:1  
刘卫东  李峰  孙伟 《冰川冻土》2012,34(1):114-119
处于甘肃河西干旱区的金川公司在生产过程中产生了大量含有重金属离子的工业废水、废渣,废水排放会对地下水水质产生影响,其重金属离子会对人体有危害.重点对尾矿库排水对当地地下水水质影响进行了研究分析,对库区地下水污染现状进行了调查.绘制了尾矿库排水影响区的地下水中Ni、Cu、Zn和Cr四种主要元素平面分布等值线图,分析了重金属离子污染来源;通过建立物理、数学模型,对尾矿排出废水中主要污染物(Ni、As、Cu、Cr、Cd、SO24-等组分)分布进行了模拟预测,对各类污染物可能造成的危害进行了分析,建议加强地下水质监测和处理排放.  相似文献   
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