Equilibrium study and kinetics of Cu removal from water by zeolite prepared from oil shale ash

Engineered zeolite was produced from oil shale ash by reaction with sodium hydroxide in a closed vessel reactor. This adsorbent was used for removal of copper ions from aqueous solution. The maximum adsorption capacity was 504.6 mg Cu²⁺/g zeolite. Kinetic studies showed that the rate of adsorption of copper is increased with increasing the solution pH and temperature, quantity of the zeolite and agitation speed. The kinetic data were fitted to homogeneous micropore model and found that the mass transfer coefficient and diffusivity of the Cu²⁺ are directly affected by the kinetic parameters. The increase in solution concentration will decrease the mass transfer coefficient while diffusivity is increased.     

改性油页岩灰渣对水中DNBP吸附去除效果

采用PDMDAAC改性方法对油页岩灰渣进行改性,确定最佳改性方案,并研究了环境因素对改性油页岩灰渣吸附DNBP的影响。实验研究结果表明,油页岩灰渣经20 g/L 的PDMDAAC处理时,对DNBP的吸附能力最强。在吸附温度为30℃,初始溶液pH值为4的条件下,0.3 g 的改性油页岩灰渣对30.0 mg/L DNBP溶液50 mL,吸附120 min时,其吸附率达到94.48%以上。在实验条件下,改性油页岩灰渣对DNBP的吸附符合Langmuir和Freundlich等温吸附方程,相关系数分别为0.9985和0.9776,其对DNBP的理论饱和吸附量达到6.196 mg/g。改性油页岩灰渣对DNBP的吸附主要归因于离子交换和表面吸附作用。     

我国页岩气开发区域水环境差异及保护政策

页岩气开发过程会对水资源产生消耗和污染。从我国页岩气开发区域水环境自然生态差异角度入手,分析了大规模开发可能给当地工农业、居民及区域生态环境用水带来的影响,建议政府部门在政策方针、影响标准、法规制度、风险评估、应急机制、责任制度和管控机制等方面做好区域水环境管理工作;开发企业做好水环境内化管理工作;社会公众做好监督参与工作等。     

页岩气开采对水环境的影响及其治理技术研究

页岩气是一种清洁、低碳、高储量的非常规天然气能源,已成为全国油气资源勘探开发的新亮点,其快速发展影响着世界能源格局.然而,页岩气开采带来了巨大的环境风险,如水污染、大气污染、固体废弃物污染和土壤污染等.文章主要分析了页岩气钻井过程、压裂过程及采气过程可能出现的水环境问题,如水资源消耗、地表水污染及地下水污染等;总结了针对不同类型废水的处置措施及处理技术,以期为处理页岩气开采过程中产生的不同类型的废水提供理论依据.     

页岩气压裂返排液的分析与双效MVR处理

对西南地区某页岩气田压裂返排液进行了分析,在此基础上采用双效机械蒸汽再压缩(MVR)系统对其进行处理,建立了完整的计算模型,并对影响系统的主要参数进行了探讨。压裂返排液分析结果表明:蒸发浓缩液黏度与相同浓度氯化钠溶液的黏度相近,可排除因有机物富集导致其在蒸发器内壁附着而影响传热系数及堵塞蒸发器的可能。模型计算结果表明:进料含盐率由2%增至6%时,压缩机比功耗与压缩机进气量的降幅均小于4.0%,两效蒸发器面积分别减小约4.3%和18.5%;传热温差由4℃升至8℃时,压缩机比功耗增加约51.0%,两效蒸发器面积均减小约49.6%;在系统安全运行的前提下,提高蒸发温度可降低系统能耗。     

The effect of admixed material on the minimum explosible concentration of oil shale

The minimum explosible concentration (MEC) in the air atmosphere at the boundary between an explosion and no explosion in a dust cloud, has been investigated for several particle sizes of oil shale and for mixtures of oil shale and inert powder of different particle size. Limestone, stone dust and coarse particle size of oil shale were used as inert materials. Measurements were made in a standard small vertical tube apparatus. The results obtained indicated that the minimum explosible concentration is dependent on the particle size, i.e., values of MEC decrease with a decrease in the size of the particles. Below 70 μm, values of MEC become almost constant. Admixture of limestone as low as 5% to oil shale is sufficient to reduce the MEC values significantly.     

The use of best management practices to respond to externalities from developing shale gas resources

The public is concerned that activities accompanying hydraulic fracturing in the development of shale gas resources are unnecessarily adversely affecting them and the environment and is petitioning elected representatives to take actions to reduce risks. The health risks associated with fracturing chemicals and air pollutants are relatively unknown and constitute the impetus for public concern. An evaluation of state legal and regulatory provisions regarding best management practices discloses that states are not adopting timely regulations to protect people and the environment from activities accompanying hydraulic fracturing. Simultaneously, regulatory policy concerning negative externalities suggests that governments underinvest in the protection of human health and environmental quality. Governments have choices in protecting people from dangers that accompany shale gas development. Due to the risks of injuries and unpaid damages from shale gas development, governmental policies need to evolve to accord people greater health protection.     

贵州开阳地区富硒地层及风化土壤地球化学特征

通过对开阳地层和土壤调查,发现灯影组、牛蹄塘组等地层富集硒元素,由其风化而来的土壤也富硒。富硒地层同时还富集Mo、As、Cd、Sb、Ba、Co、Ni、Tl、V、Zn等元素,而相对缺Ag、Bi、Cr、Ga、Rb、Sr、Ta、Zr等元素;富硒地层风化形成的土壤中As、Ba、Cd、Co、Mo、Ni、Sb、Se、Tl等元素对基岩有明显的继承而富集;Pb元素则在基岩风化过程中流失而亏损;Cu、Sc、V、Zn元素在基岩风化后明显富集;而Ni、Co、Cd则具有对基岩的继承和后期风化富集的双重特征。研究表明该地区硒的富集是热水沉积、深部物质沿白马洞深大断裂迁移、热卤水的迁移混合,铀矿化以及大量硫化物的存在共同作用的结果。开阳富硒地层及风化土壤中稀土元素总量∑REE为66.61～609.13×10-6,LREE/HREE比值为1.17～5.40,(La/Yb)N=5.08～15.72>1,REE分布模式为右倾型,轻稀土段右倾明显,(La/Sm)N=1.43～7.44>1,为LREE富集型,重稀土段则相对平缓,(Tb/Yb)N=1.01～2.39。通过对微量、稀土元素的分析表明,富硒的黑色岩系形成于缺氧条件下的低温热水沉积环境。     

两种填料在曝气生物滤池中处理生活污水的对比研究

在上流式曝气生物滤池中,使用不规则形状页岩及球形粘土陶作填料处理生活污水,在相同工艺条件下,比较了它们对污水的处理效果,采用两种填料的单级滤池出水,主要水质指标(CODer,SS)达到国家排放标准,而NH3-N要达标排放需在二级滤池中进一步处理.     

涪陵页岩气田油管腐蚀行为研究

采用细菌分析、实验模拟和现场腐蚀挂片等方法,研究了涪陵页岩气田在清水压裂和掺污水压裂后N80油管的腐蚀行为。研究结果表明:压裂方式对产出水的性质影响不大,清水压裂和掺污水压裂的生产井产出水均存在细菌。压裂方式对N80油管的腐蚀没有明显影响,不同深度的腐蚀模拟实验均发生了小孔腐蚀;对清水压裂井和掺污水压裂井开展了88天和129天的现场腐蚀挂片实验,均匀腐蚀速率分别为0.01,0.02 mm/a,但均出现了明显的小孔腐蚀。腐蚀模拟实验和现场挂片实验的金属表面均存在明显结垢和细菌腐蚀,腐蚀主要呈现为小孔腐蚀。