Soil remediation mechanisms

The BioGenesis soil remediation and cleaning products can be used for general-purpose and emulsion-degreasing applications in oil refining, utility, automotive, manufacturing, and transportation industries. They can be used in situ or in conjunction with mechanical cleanup systems. 

The use of microemulsions in the context of washing and cleaning was recently reviewed [1]. There seem to be no reasons to believe that any fundamental new impact is needed in this area from a physicochemical point of view. Large-scale applications in the area of soil remediation can be expected in the near future. In this context it will be essential to estimate microemulsion formation, price, chemical performance, and mechanisms of retention (adsorption) on the solid material when designing these kinds of washing systems. Microemulsions for use in soil remediation have been summarized by Miller and coworkers [12,13] and Schwuger and coworkers [14,15]. 

Electrokinetic Transport in Soil Remediation, Fig. 2 Transport mechanisms in electrokinetic remediation... 

Abstract Though, naturally occurring and chemically synthesized (pure grade) zeolites have been used for various industrial applications in the past, their increasing demand for several novel applications (viz., as adsorbent or absorbent for waste water decontamination, soil remediation as fertilizers, aqua-culture purification, etc.) warrants their enhanced production. With this in view, several researchers have attempted to synthesize zeolites from the fly ash, an abundantly available industrial by-product, as described in this chapter. Furthermore, different methods employed for synthesis of fly ash zeolites, the mechanism of zeolites formation and potential fields of their appUcations have also been included herein. 

Bacteria and their composites with soil minerals or organic matter are capable of taking up a wide range and variety of toxic metals in soil environments. Research done over the last decade or so has greatly improved our understanding of the mechanisms on biosorption of metals and bacte-ria-metal-soil component interactions. However, more studies from molecular level are needed in order to enhance the ability of bacteria and their association with soil components to remediate toxic metals-contaminated soils. The focus of future investigations should be on the mechanisms by which metals are sorbed and bound by bacterial cell surfaces and bacteria-soil/mineral composites. In this connection, X-ray absorption spectroscopy (XAS) is a promising technique because it can provide information about... 

Srinath T, Verma T, Ramteke PW, Garg SK (2002) Chromium biosorption and bioaccumulation by chromate resistant bacteria. Chemosphere 48 427-435 Stephen JR, Macnaughton SJ (1999) Developments in terrestrial bacterial remediation of metals. Curr Opinion Biotechnol 10 230-233 Tabak HH, Lens P, van Hullebusch ED, Dejonghe W (2005) Developments in bioremediation of soils and sediments polluted with metals and radionuclides 1. Microbial processes and mechanisms affecting bioremediation of metal contamination and influencing metal toxicity and transport. Rev Environ Sci Bio/Technol. 4 115-156... 

In all, 11 vertical soil vapor extraction wells and 9 vertical air sparge wells were installed in the treatment area. Sand chimneys (boreholes filled with coarse sand) were also installed to facilitate vertical air circulation. Mechanical remediation equipment and systems control installed for remediation were mosdy automated with minimal operator control required. 

On the basis of the feasibility studies, an in situ technology was applied for the biological remediation of TNT and its transformation products. Microbiological transformation of TNT in the soil was stimulated by the addition of a carbon source and iron particles. The amount of additive was 51/m molasses and 5kg/m iron particles. Thus for the treatment of the whole 2,000m site, there was a requirement for lOm molasses and lOt iron. The addition of molasses and a subsequent mechanical tillage to a... 

Reclaim is a passive, in situ technology that uses a hydrophobic porous polymer to attract, adsorb, and concentrate petroleum hydrocarbons and volatile organic compounds (VOCs) from soils and/or groundwater. Reclaim is considered a passive treatment technology because it requires no mechanical equipment remediation consists of placing polymer-filled canisters in recovery wells and allowing the containers to attract and adsorb organic contaminants. Reclaim canisters are then recycled and contaminants recovered for analysis and/or disposal. This polymer extracts contaminants whether they are in liquid phase, vapor phase or dissolved phase in water. 

Although the above studies conducted with packed columns are important from a fundamental standpoint as they relate to the mechanisms of cell sorption to solid surfaces, in situ remediation of contaminants in subsoils requires microbial transport in well-structured soils. The presence of soil macropores that facilitate preferential water flow is well appreciated (Thomas Phillips, 1979). Sorption phenomena are less important when bacterial transport occurs through structured soils in which cells pass unimpeded through relatively large conduits (Smith et al., 1985). 

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