Electrocoagulation of vegetable oil refinery wastewater using aluminum electrodes

Electrocoagulation with aluminum electrodes was used to treat the vegetable oil refinery wastewater (VORW) in a batch reactor. The effects of operating parameters such as pH, current density, PAC (poly aluminum chloride) dosage and Na(2)SO(4) dosage on the removal of organics and COD removal efficiency have been investigated. It has been shown that the removal efficiency of COD increased with the increasing applied current density and increasing PAC and Na(2)SO(4) dosage and the most effective removal capacity was achieved at the pH 7. The results indicate that electrocoagulation is very efficient and able to achieve 98.9% COD removal in 90 min at 35 mAcm(-2) with a specific electrical energy consumption of 42 kWh(kgCOD(removed))(-1). The effluent was very clear and its quality exceeded the direct discharge standard.     

焦化受煤塔爆炸的原因分析

焦化受煤塔是一个储存和转运混合煤的设施,冶金炼焦混合煤的颗粒度为2-4mm,且煤粉中含有一定的湿度(水分),在一般的环境下发生爆炸的可能微乎其微.为什么会发生爆炸?爆炸的原因是什么?只有分析出准确的原因,才能制订有效的防范措施,防止事故的重复发生.     

化学需氧量现有2种标准分析方法若干问题研究

《水质化学需氧量的测定重铬酸盐法》(HJ 828-2017)和《高氯废水化学需氧量的测定氯气校正法》(HJ/T70-2001)是测定水中CODCr现有有效的2种标准方法.针对这2种方法存在的问题,通过实验给出操作建议.指出,对高氯废水稀释后采用《HJ828-2017》方法测定水中CODCr时,稀释倍数太大或稀释后COD...     

石墨粉末润湿特性及其表面自由能的研究

利用毛细上升法测定了去离子水对石墨粉末的接触角,分析温度对石墨粉末润湿性的影响,并测算了石墨粉末的表面自由能,对将石墨用作净水滤料有指导作用.在20～40℃温度范围内接触角变化不大,平均为84.11°.其主要原因是表面张力σ和黏度η随温度变化对接触角的影响相反,综合作用结果导致接触角随温度变化不大.石墨粉末表面色散自由能为21.8 mJ·m-2,极性自由能为1.8 mJ·m-2,总的表面自由能约为23.6 mJ·m-2,以色散自由能为主.这是去离子水能够湿润石墨粉末,但湿润性相对较差的一个原因.可知极性流体对石墨粉末的润湿性比较差.     

冷冻胶粉粒度对橡胶胶料力学性能的影响

研究了冷冻胶粉粒度对橡胶胶料力学性能的影响,发现添加冷冻胶粉会使胶料的力学性能下降,胶粉粒度越大,胶料性能下降的程度越严重。同时还发现,薄通处理可以改善胶粉的表面活性,减轻胶粉粒度对胶料性能的影响,改善胶料的力学性能。     

UF膜与混凝粉末活性炭联用处理冬季黄河水

针对低温低浊水处理的难题,采用混凝和粉末活性炭预处理超滤系统对冬季黄河水进行了净化研究,通过投加混凝剂Al(2SO)4·318H2O以及粉末活性炭,比较了其对于原水的处理效果和对膜过滤性能的影响。试验结果表明,混凝超滤系统用于处理冬季黄河水在技术上是可行的,混凝剂与粉末活性炭对水中污染物质的去除和膜过滤性能有很大的影响;调整合适的操作参数,其对低温黄河水中的高锰酸盐指数、UV254、NH3-N、铁和浊度的平均去除率分别达到70%、60%、30%、80%和96%以上,出水水质达到《生活饮用水源水质标准》(CJ3020-93)的标准。对于已污染的膜,水反冲洗、水/酸洗、水/碱洗可使膜通量恢复至新膜的38%,82%,89%。     

磷石膏的利用和处理

综述了国内外对磷石膏的利用和处理技术，同时介绍了提取稀土元素和贵重金属，低能耗的石膏砖等新的应用技术，比较了各种方法的优缺点，提出要尽快开发磷石膏综合利用的新工艺、新方法，早日解决其污染问题。     

Preparation, characterization, and photocatalytic activities of boron- and cerium-codoped TiO2

Boron- and cerium-codoped TiO2 photocatalysts were synthesized using modified sol-gel reaction process and characterized by X- ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS）, particle size distribution （PSD）, diffuse reflectance spectra （DRS）, and Brunauer-Emmett-Teller （BET）. The photocatalytic activities were evaluated by monitoring the degradation of dye Acid Red B （ARB）. The results showed that the prepared photocatalysts were mixed oxides mainly consisting of titania, ceria, and boron oxide. The structure of TiO2 could be transformed from amorphous to anatase and then to rutile by increasing calcination temperature; the transformation being accompanied by the growth of particle size without any obvious change in phase structure of CeO2. The XPS of B1.6Ce1.0-TiO2 prepared at 500℃ showed that a few boron atoms were incorporated into titania and ceria lattice, whereas others existed as B2O3. Cerium ions existed in two states, Ce^3＋ and Ce^4＋, and the atomic ratio of Ce^3＋/Ce^4＋ was 1.86. When boron and cerium were doped, the UV-Vis adsorption band wavelength showed an obvious shift toward the visible range （〈526 nm）. As the atomic ratio of Ce/Ti increased to 1.0, the absorbance edge wavelength increased to 481 nm. The absorbance edge wavelength decreased for higher cerium doping levels （Ce/Ti=2.0）. The particles size ranged from 122 to 255 nm with a domain at 168 nm （39.4%）. The degradation of ARB dye indicated that the photocatalytic activities of boron- and cerium-codoped TiO2 were much higher than those of P25 （a standard TiO2 powder）. The activities increased as the boron doping increased, whereas decreased when the Ce/Ti atomic ratio was greater than 0.5. The optimum atomic ratio of B/Ti and Ce/Ti was 1.6 and 0.5, respectively.     

青岛春节期间大气污染特征及烟花燃放一、二次贡献分析

我国北方地区冬季采暖期大气污染事件频发,期间硝酸盐成为促进PM_2.5增加的主要因素.然而在烟花燃放期间,硫酸盐的累积却强于硝酸盐,形成不同的污染特征.对春节期间（2019年2月2~10日）青岛近郊在线离子色谱观测数据,结合国控自动监测站数据进行综合分析.结果表明,研究期间观测到大气颗粒物累积事件、沙尘过境事件和烟花燃放事件.烟花燃放高峰期,其对PM_2.5和PM₁₀的一次贡献率分别为69.8%和63.8%.相比颗粒物累积期间硝酸盐有更明显的累积,硫酸盐在烟花燃放期间先于硝酸盐生成,并存在更强的累积.分离得到烟花燃放的一次贡献因子n（SO₄^2-）/n（K⁺）和n（NO₃^-）/n（K⁺）特征摩尔比分别为1.2和1.3;利用该比值估算得到对SO₄^2-和NO₃^-二次贡献因子,在较稳定的气象条件下分别为一次贡献因子的2.1倍和1.6倍;但在强的干冷空气过境时,二次贡献因子大幅降低,与一次贡献因子相当.     

类水滑石复合材料吸附去除水中硫酸根离子

用共沉淀法制备的类水滑石复合材料作为吸附剂去除水中的硫酸根离子.利用XRD、FT-IR、SEM和EDS元素分析对类水滑石复合材料的结构和组成进行了分析.研究了时间、p H值和共存离子对吸附量的影响.结果表明,类水滑石复合材料是锌铝硝酸根类水滑石和锌铝苯丙氨酸类水滑石的复合材料;类水滑石复合材料对硫酸根离子具有良好的吸附性能,最大吸附量可达到52.75 mg·g~(-1);准二级动力学模型对数据的拟合效果最好,说明吸附速率是由化学吸附控制的;吸附过程更符合Freundlich吸附等温模型,说明类水滑石复合材料对硫酸根离子的吸附是多层吸附;热力学参数表明在常温下吸附过程是自发的吸热过程;类水滑石复合材料吸附硫酸根离子主要是通过离子交换、静电引力作用以及物理吸附的途径来实现的.实验结果表明,该类水滑石复合材料是一种潜在的去除水中硫酸根离子的吸附剂.