Groundwater remediation applications

Chang, L. C, Shoemaker, C. A., and Liu, P. L. F. (1992). "Optimal time-varying pumping rates for groundwater remediation Application of a constrained optimal control algorithm." Water Resour. Res., 28(12), 3157-3171. 

Harwell, J.H., 1992. Factors affecting surfactant performance in groundwater remediation applications. In Subsurface Contaminants, D.A. Sahatini, and R.C. Knox (eds.), Washington, D.C. American Chemical Society, Chap. 10, pp. 124-132. 

These examples help to illustrate the versatility of activated carbon in standard water treatment applications. Another application which merits a distinct discussion is groundwater remediation. This is discussed below. 

The application of adsorption to contaminated groundwater remediation is not only an important subject, but one we could expand upon into several volumes unto itself. At best, all we can do is try to provide a concise overview in this volume. 

Gavaskar, A., Gupta, N., Sass, B., Janosy, R., and Hicks, J., Design Guidance for Application of Permeable Reactive Barriers for Groundwater Remediation, Prepared for US Air Force, Air Force Research Laboratory, March 2000. 

Groundwater remediation, activated carbon application, 4 753. See also Groundwater bioremediation Groundwater treatment Groundwater samples, retrieving, 22 844-845, 846... 

Traditionally air sparging has been used as a groundwater remediation tool. Occasionally, however, it has been successfully used to remediate the vadose zone. In this application, the compressed air is injected through a well screen that is open to the VOC-contaminated area. The injection wells may be either vertical or horizontal (Figure 10.7). In this setting, the injected air is usually captured by a corresponding set of SVE wells (Figure 10.8). Properly spaced patterns of injection and recovery wells are necessary for efficient operation. 

The same energy input dispersed over a broader area results in significant enhancement of reaction rates and energy utilization efficiency. The low energy utilization efficiency may limit the use of direct probe sonolysis to special applications such as groundwater remediation or for low-flow pretreatment of hazardous industrial wastes. However, sonolysis does not require the addition of chemical additives to achieve a viable degradation rate. 

Focht R., Vogan J., and O Hannesin S. (1996) Field application of reactive iron walls for insite degradation of volatile organic compounds in groundwater. Remediation (Summer), 81-94. 

In addition to transformation by corrodable metals (such as Fe° and Zn°), bimetallic combinations of a catalytic metal with a corrodable metal (such as Pd/Fe or Ni/Fe) have also been shown to transform a variety of contaminants. In most cases, rates of transformation by bimetallic combinations have been significantly faster than those observed for iron metal alone [26,96,135-139]. Not only have faster transformation rates been observed with bimetallic combinations, but, in some cases, transformation of highly recalcitrant compounds, such as polychlorinated biphenyls (PCBs), chlorinated phenols, and DDT has been achieved [24,140,141]. The mechanism responsible for the enhanced reactivity with bimetallic combinations is still unclear however, it has been suggested that electrochemical effects, catalytic hydrogenation, or intercalation of H2 may be responsible. A likely limitation to the full-scale application of bimetallic combinations to groundwater remediation is deactivation of the catalytic surface either by poisoning (e.g., by sulfide) or by formation of thick oxide films [136,142,143]. 

Naftz, D., Morrison, S.J., Fuller, C.C., and Davis, J.A. (Eds.), Handbook of Groundwater Remediation Using Permeable Reactive Barriers - Applications to Radionuclides, Trace Metals, and Nutrients . Academic Press, San Diego (2002). 

Conca L, Strietelmeier E., Lu N., Ware S. D., Taylor T. P., Kaszuba L, and Wright 1. (2002) Treatability study of reactive materials to remediate groundwater contaminated with radionuclides, metals, and nitrates in a four-component permeable reactive barrier. In Handbook of Groundwater Remediation Using Permeable Reactive Barriers—Applications to Radionuclides, Trace Metals, and Nutrients (eds. D. L. Naftz, S. 1. Morrison, J. A. Davis, and C. C. Fuller). Academic Press, San Diego, CA, pp. 221-252. 

Ozone-based AOPs are being used increasingly to treat landfill leachates. " They are also used for ground-water treatment to destroy trichloroethylene (TCE), tetrachloroethylene, and pentachlorophenol. In addition, they are used for groundwater remediation at Superfund sites in the United States to destroy volatile organic compounds and benzidines. Another application of ozone-based AOPs involves their use at U.S. ammunition plants to destroy explosives. ... 

As a result, hydrophilidty is introduced to the surface. The world production of activated carbons in 2002 was estimated to be about 750000 metric tons. There is discrimination between gas- and liquid-phase carbons. Typical liquid-phase applications are potable water treatment, groundwater remediation, and industrial and municipal waste-water treatment and sweetener decolorization. Gas-adsorption applications are solvent recovery, gasoline emission control, and protection against atmospheric contaminants. 

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