Landfarming

Land Farming

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Principio del formulario

Final del formulario
Background
Land farming is a bioremediation treatment process that is performedin the upper soil zone or in biotreatment cells. Contaminated soils, sediments, or sludges are incorporated into the soil surface and periodically turned over or tilled to aerate the mixture.Applicability
This technique has been successfully used for years in the management and disposal of oily sludge and other petroleum refinery wastes. In situ systems have been used to treat near surfacesoil contamination for hydrocarbons and pesticides. The equipment employed in land farming is typical of that used in agricultural operations. These land farming activities cultivate and enhancemicrobial degradation of hazardous compounds. As a rule of thumb, the higher the molecular weight (i.e., the more rings within a polycyclic aromatic hydrocarbon), the slower the degradation rate. Also, themore chlorinated or nitrated the compound, the more difficult it is to degrade [1,2].

Limitations
Factors that may limit the applicability and effectiveness of the process include: (1) large spacerequirements; (2) the conditions advantageous for biological degradation of contaminants are largely uncontrolled, which increases the length of time to complete remediation, particularly forrecalcitrant compounds; (3) inorganic contaminants are not biodegraded; (4) the potential of large amounts of particulate matter released by operations; and (5) the presence of metal ions may be toxic tomicrobes and may leach from the contaminated soil into the ground [2].
Hydrocarbon compounds that have been identified as being not readily degraded by land farming include creosote, pentachlorophenol(PCP), and bunker C oil [3].

Performance
The effectiveness of land treatment of petroleum products has been confirmed in controlled experiments in both laboratory and field experiments. It has been...