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61.
Oil refinery wastewater was treated using a coupled treatment process including electrocoagulation (EC) and a fixed film aerobic bioreactor. Different variables were tested to identify the best conditions using this procedure. After EC, the effluent was treated in an aerobic biofilter. EC was capable to remove over 88% of the overall chemical oxygen demand (COD) in the wastewater under the best working conditions (6.5 V, 0.1 M NaCl, 4 electrodes without initial pH adjustment) with total petroleum hydrocarbon (TPH) removal slightly higher than 80%. Aluminum release from the electrodes to the wastewater was found an important factor for the EC efficiency and closely related with several operational factors. Application of EC allowed to increase the biodegradability of the sample from 0.015, rated as non-biodegradable, up to 0.5 widely considered as biodegradable. The effluent was further treated using an aerobic biofilter inoculated with a bacterial consortium including gram positive and gram negative strains and tested for COD and TPH removal from the EC treated effluent during 30 days. Cell count showed the typical bacteria growth starting at day three and increasing up to a maximum after eight days. After day eight, cell growth showed a plateau which agreed with the highest decrease on contaminant concentration. Final TPHs concentration was found about 600 mgL−1 after 30 days whereas COD concentration after biological treatment was as low as 933 mgL−1. The coupled EC-aerobic biofilter was capable to remove up to 98% of the total TPH amount and over 95% of the COD load in the oil refinery wastewater. 相似文献
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《The Cartographic journal》2013,50(3):195-197
AbstractA novel method called multidirectional visibility index (MVI) has been developed and verified. The MVI improves standard cartographic analytical shading with a number of enhancements to topographic detail and prominent structures, i.e. the portrayal of flat areas in lighter tones, the accentuation of morphologic edges, and the multiscale visualisation of morphologic terrain features. The procedure requires a digital elevation model (DEM) and involves the following steps: visibility mask computation; the respective multidirectional altering of the azimuth and elevation angle; the generation of continuous grid MVIs that indicate upper/lower views, quasi-slope, and relative relief; and an appropriate visualisation of the relevant MVI as a standalone technique or in combination with standard hill-shaded relief. The modelling parameters are robust and therefore highly adaptive to different landforms. 相似文献
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LI Xiaoyang TIAN Yingying ZHANG Xin SONG Gang ZHAO Ming LIANG Jinqiang HUANG Wei MENG Fanle 《《地质学报》英文版》2022,96(2):701-712
A new gas hydrate reservoir stimulation method of in-situ fracturing with transient heating is proposed, in line with analysis of the technological bottlenecks faced by marine gas hydrate production. This method injects the developed chemical reagents into a hydrate reservoir through hydraulic fracturing, releasing heat during the chemical reaction to increase the hydrate decomposition rate. The chemical reaction product furthermore has a honeycomb structure to support fractures and increase reservoir permeability. Based on the geological model of natural gas hydrate in the South China Sea, three development methods are simulated to evaluate hydrate production capacity, consisting of horizontal well, fractured horizontal well and in-situ fracturing with transient heating well. Compared with the horizontal well, the simulation results show that the cumulative gas production of the fractured horizontal well in one year is 7 times that of the horizontal well, while the cumulative gas production of in-situ fracturing with transient heating well is 12 times that of the horizontal well, which significantly improves daily efficiency and cumulative gas production. In addition, the variation patterns of hydrate saturation and temperature-pressure fields with production time for the three exploitation plans are presented, it being found that three sensitive parameters of fracture conductivity, fracture half-length and fracture number are positively correlated with hydrate production enhancement. Through the simulations, basic data and theoretical support for the optimization of gas hydrate reservoir stimulation scheme has been provided. 相似文献
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对2018年飞机人工增雨作业时的77个天气样本进行分析,以大气环流形势配合冷空气入侵青海的不同路径将人工增雨降水过程分为4种环流型:两槽一脊型、东高西低型、纬向环流型、横槽转竖型。作业云系以层状云和积层混合云为主;主要作业层风速在16 m·s-1左右;作业层主导风向在230°~280°。雷达回波强度和雷达回波顶高在4种环流型中没有明显区别。卫星反演云顶高度中东高西低型云系平均发展较深厚,纬向环流型和横槽转竖型中云系发展较高但并不深厚;云顶温度最低在-40℃;最大光学厚度在13左右;过冷层厚度在2.7 km左右。云内微观条件中:有效粒子半径在13 μm左右;液水路径在东高西低型中较高在209 μm左右。 相似文献
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冬季层状云实施人工增雨作业可行性探讨 总被引:1,自引:1,他引:0
通过对百色市2004年至2007年冬季8次天气过程的22次层状云或层积混合云增雨作业个例分析,推断冬季对层状云或层积混合云进行增雨作业的环流背景、增雨潜力、催化可播高度和作业时机,得出百色市冬季对层状云或层积混合云开展增雨作业,只要存在有利的天气条件和持续长的时间,在降水云系的发展旺盛时期通过火箭将A gI焰剂播撒在-5℃~-10℃可播高度区域内,可收到良好的增雨作业效果结论。 相似文献
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海南乐东降水特征与干旱及人工增雨潜力分析 总被引:1,自引:1,他引:0
利用海南省乐东县境内的乐东站和莺歌海盐场气象站及所属5个单位气象站1977~2006年的地面观测资料,对东县降水特征与干旱进行分析;并根据气象学原理对乐东县人工增雨潜力进行了分析,为当地政府进行抗旱减灾,找出了科学依据。 相似文献
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