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采用微波辐照技术修复氯丹污染土壤,以氯丹的挥发率和分解率为主要评价指标,研究了微波辐照条件对土壤修复效果的影响。实验结果表明:氯丹的挥发率随微波辐照功率的增大而增大,而氯丹的分解率则无明显变化;当活性炭与土壤质量比为9∶120时,氯丹的去除效果最好,去除率达89%;氯丹的挥发性能在前20min内随微波辐照时间的延长而增强,而氯丹的分解性能则刚好相反;当土壤含水率为15%时,氯丹的挥发率最高,为2.5%,而氯丹分解率最小,为16.8%;在酸性偏中性范围内氯丹的去除效果较差,随土壤p H的不断增大,氯丹的挥发率明显升高,且氯丹的分解率也增大。 相似文献
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采用电动力修复技术处理Pb、Cd复合污染土壤,考察了柠檬酸和乙二胺四乙酸二钠(EDTA)作为电解液对棕壤(ZR)和红壤(HR)两种我国典型壤质中Pb、Cd去除效果的影响。实验结果表明:在电压梯度为2 V/cm,修复时间为4 d的条件下,ZR的最佳电解液为EDTA,Pb、Cd平均去除率为13.2%和17.8%,HR的最佳电解液为柠檬酸,Pb、Cd的平均去除率为20.0%和33.8%;延长修复时间至10 d能显著提高HR中Pb、Cd的去除率,电解液为柠檬酸时Cd平均去除率达91.1%,电解液为EDTA时Pb平均去除率达63.2%,修复后土壤中Cd和Pb含量均低于建筑用地土壤污染风险筛选值。综合考虑能耗及修复效果,EDTA是高效且经济的修复电解液。 相似文献
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以贵州省铜仁市汞矿区汞污染土壤为研究对象,分别采用KI、Na_2S_2O_3、乙二胺四乙酸、柠檬酸、酒石酸、十二烷基硫酸钠溶液对其进行淋洗修复,筛选出合适的淋洗剂,优化了淋洗条件,并探索了淋洗液的处理方法。实验结果表明:对该土壤淋洗效果最好的淋洗剂为Na_2S_2O_3,最佳淋洗条件为Na_2S_2O_3浓度0.01 mol/L、固液比(g/m L)1∶5、淋洗时间4 h、淋洗次数1次,在此条件下土壤中总汞的淋洗率为13.41%,有效态汞含量可降至原来的61.54%;Na2S对淋洗液中的汞具有较好的去除效果,每升淋洗液加入0.6 g Na_2S处理后,即可满足GB8978—1996《污水综合排放标准》。 相似文献
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根据电子废弃物拆解场地的污染特征,以复合重金属(Cu,Cd,Pb)污染高岭土为研究对象,考察了电动技术对污染土壤的修复效果。实验结果表明:在电压梯度为1 V/cm、阳极液为自来水、阴极液为柠檬酸-柠檬酸钠缓冲液(pH=5)、靠近阴极设置活性炭渗透反应墙(PRB)的条件下电动修复96 h后,Cu,Cd,Pb的平均去除率分别可达79.93%,99.43%,39.36%;土壤的酸碱性对电动修复效果影响显著,通过在阴极添加缓冲液维持土壤偏酸性条件,有利于重金属污染物的电动去除;在靠近阴极设置活性炭PRB可富集重金属,减少阴极液的污染;迁移率大的酸可提取态重金属较易去除,残渣态重金属稳定性强,去除率较低。 相似文献
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Preliminary studies on potential remediation of acid mine drainage‐impacted soils by amendment with drinking‐water treatment residuals 下载免费PDF全文
Mining operations result in a wide range of environmental impacts: acid mine drainage (AMD) and acid sulfate soils being among the most common. Due to their acidic pH and high soluble metal concentrations, both AMD and acid sulfate soils can severely damage the local ecosystems. Proper post‐mining management practices are necessary to control AMD‐related environmental issues. Current AMD‐impacted soil treatment technologies are rather expensive and typically not environmentally sustainable. We conducted a 60‐day bench‐scale study to evaluate the potential of a cost‐effective and environment‐friendly technology in treating AMD‐impacted soils. The metal binding and acid‐neutralizing capacity of an industrial by‐product, drinking water treatment residuals (WTRs) were used for AMD remediation. Two types of locally generated WTRs, an aluminum‐based WTR (Al‐WTR) and a lime‐based WTR (Ca‐WTR) were used. Highly acidic AMD‐impacted soil containing very high concentrations of metals and metalloids, such as iron, nickel, and arsenic, was collected from the Tab‐Simco coal mine in Carbondale, Illinois. Soil amendment using a 1:1 Al‐ and Ca‐WTR mix, applied at 5 and 10 percent rates significantly lowered the soluble and exchangeable fractions of metals in the AMD‐impacted soil, thus lowering potential metal toxicity. Soil pH increased from an extremely acidic 2.69 to a near‐neutral 6.86 standard units over the 60‐day study period. Results from this preliminary study suggest the possibility of a successful scale‐up of this innovative, cost‐effective, and environmentally sustainable technology for remediating AMD‐impacted acid sulfate soils. 相似文献
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采用内酯型槐糖脂(SL50)修复石油污染土壤。通过单因子实验与正交实验,考察了槐糖脂溶液质量浓度、振荡时间、反应体系初始pH、NaCl加入量以及固液比(土壤质量与表面活性剂溶液体积之比)对污染土壤石油烃洗脱率的影响。单因子模型回归分析结果表明,参数变量均符合二次拟合模型,槐糖脂溶液质量浓度、反应体系初始pH以及NaCl加入量的二次模型拟合效果较好。正交实验结果表明,槐糖脂溶液质量浓度和反应体系初始pH是该实验的敏感性因子,最优洗脱条件为槐糖脂溶液质量浓度40 mg/L、反应体系初始pH 9、NaCl加入量6%(w)。 相似文献
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The horizontal reactive media treatment well (HRX Well®) for passive in situ remediation: Design,implementation, and sustainability considerations 下载免费PDF全文
Craig E. Divine Jesse Wright Jack Wang Jeff McDonough Michael Kladias Michelle Crimi Blossom N. Nzeribe J.F. Devlin Michael Lubrecht Daniel Ombalski Billy Hodge Hoa Voscott Kathleen Gerber 《补救:环境净化治理成本、技术与工艺杂志》2018,28(4):5-16
A new in situ remediation concept termed a Horizontal Reactive Media Treatment Well (HRX Well®) is presented that utilizes a horizontal well filled with reactive media to passively treat contaminated groundwater in situ. The approach involves the use of a large‐diameter directionally drilled horizontal well filled with solid reactive media installed parallel to the direction of groundwater flow. The engineered contrast in hydraulic conductivity between the high in‐well reactive media and the ambient aquifer hydraulic conductivity results in the passive capture, treatment, and discharge back to the aquifer of proportionally large volumes of groundwater. Capture and treatment widths of up to tens of feet can be achieved for many aquifer settings, and reductions in downgradient concentrations and contaminant mass flux are nearly immediate. Many different types of solid‐phase reactive treatment media are already available (zero valent iron, granular activated carbon, biodegradable particulate organic matter, slow‐release oxidants, ion exchange resins, zeolite, apatite, etc.). Therefore, this concept could be used to address a wide range of contaminants. Laboratory and pilot‐scale test results and numerical flow and transport model simulations are presented that validate the concept. The HRX Well can access contaminants not accessible by conventional vertical drilling and requires no aboveground treatment or footprint and requires limited ongoing maintenance. A focused feasibility evaluation and alternatives analysis highlights the potential cost and sustainability advantages of the HRX Well compared to groundwater extraction and treatment systems or funnel and gate permeable reactive barrier technologies for long‐term plume treatment. This paper also presents considerations for design and implementation for a planned upcoming field installation. 相似文献
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以重庆市某铅污染场地为研究对象,选用多种稳定化药剂对土壤开展稳定化修复技术研究,着重探讨了不同单一药剂与复配药剂对土壤铅浸出浓度的影响。实验结果表明:磷酸二氢钠(MSP)、磷酸氢二钠、磷酸钠和石灰4种无机药剂中MSP的稳定化修复效果最佳,且磷酸盐类的稳定化修复效果整体上优于石灰;MSP与少量有机药剂腐殖酸复配施用的稳定化修复效果优于单独施加MSP;在MSP投加比(与土壤的质量比)为5%、腐殖酸投加比为2%、养护时间为7 d的最优工艺条件下,土壤中铅的浸出浓度由41.70 mg/L降至0.16 mg/L,低于《生活垃圾填埋场污染控制标准》(GB 16889—2008)中规定的0.25 mg/L浓度限值。 相似文献
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对海泡石进行热改性,以腐殖酸和海泡石为原料,制备了腐殖酸-海泡石复合钝化剂。采用BCR形态分析法研究了复合钝化剂对镉污染土壤的钝化效果。结果表明,制备复合钝化剂的最佳工艺条件为:腐殖酸与海泡石质量比2∶1,氢氧化钠质量浓度0.04 g/mL,热反应时间40 min,热反应温度80 ℃。复合钝化剂的最佳添加量为7%(w),培养3 d后,钝化效率达46.87%,土壤pH升高至7.02,活稳比降低为0.65,土壤中镉的释放风险显著降低。复合钝化剂修复镉污染土壤时,会促使活性态镉向稳定态镉转化,使镉在土壤中的稳定性提高。 相似文献
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基于我国可持续能源战略推行缓慢,其相关立法尤为滞后,亟待完善的现状,阐述了可持续能源的深刻内涵,并结合世界可持续能源立法的现状,分析了我国可持续能源立法中存在的问题及应对之策. 相似文献
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随着军队现代化的高速发展,严峻的资源短缺问题日益凸显,严重制约了装备的持续发展。为缓解制约装备可持续发展的资源"瓶颈",必须改变传统的粗放式发展模式,将可持续发展理念贯穿到装备全寿命周期,走资源节约型、环境友好型装备发展道路。结合我军装备建设实际情况,以实现装备可持续发展为前提,从装备科研领域、采购管理、使用管理、维修保障及退役报废5个领域入手,确定当前我军装备发展需要的新目标、新要求,借鉴国内外先进的管理理念和技术,找出适合我军特色的装备可持续发展途径,为下一步装备建设提供参考。 相似文献