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Oil as an important resource, people constantly exploitation, but also to the soil environment to bring more and more pollution. Petroleum hydrocarbons are mostly hydrophobic organic compounds less soluble in the aqueous phase, to stay for a long time in the soil environment, not only destroyed the soil structure and function, but also become a long-term source of pollution of surface water and groundwater. In addition, the hydrophobic properties of petroleum pollutants, but also seriously hampered the microbial its degradation and other repair work carried out. Therefore, to increase the solubility of hydrophobic petroleum hydrocarbon pollutants, to transfer from the soil into the aqueous phase, is one of the important aspects of the oil-contaminated soil remediation. The surfactants are a class of amphiphilic nature of the particular substance, the distribution function, and to change the interfacial tension through micelles a significant increase in the solubility of the hydrophobic organic compounds in water. The advantage of this nature, the use of surfactant solution for cleaning oil contaminated soil treatment has become a promising repair, and attracted widespread attention. This paper is divided into two main parts, laboratory experiments and pilot test device. The laboratory experiments selected several anionic and non-ionic surfactants, petroleum-contaminated soil washing treatment Shengli Oilfield severe effects of different surfactant compositions proportion and concentration, aids concentration, temperature and other conditions parameters of petroleum hydrocarbons pollutant removal effect. Pilot Test device is the design and manufacture of a device, and a series of actual repair parameter optimization experiments laid the foundation for the actual repair of engineering. The main contents of this paper and the results are summarized as follows: The experiments show that the common surfactant chemical heat cleaning process of contaminated soil, the optimal removal rate of 76.31%, the reaction conditions: SDS mass concentration of 1.0 g / L, TW20 mass concentration of 1.0 g / L, the mass concentration of additives Na2SiO3 6 g / L, solid-liquid ratio of 1 g/20 mL, magnetic stirrer and 75 ℃ water bath heating 1h, the removal rate was 76.31%, three times cleaning to get rid of a total of 84.77% of the oil pollutants, contaminated soil TPH content decreased from 32.16% to 4.89%. Washing wastewater reuse experiments show the: washing sewage still contains effective cleaning ingredients, still has a cleaning effect on petroleum hydrocarbon pollutants; sewage back with either reduce cleaning costs, but also can reduce the wastewater discharge, reduce environmental pollution. This paper also investigated the different temperatures ultrasonic agitation of oil contaminated soil samples cleaning effect, showed that ultrasound assisted cleaning can significantly improve cleaning effect principle is based on the ultrasonic cleaning cavitation, the liquid pressure changes and the rapid formation of numerous tiny vacuum bubbles and rapid implosion will instantly produce a powerful impulse energy, destruction of petroleum hydrocarbons and soil combine to make it easy to desorption. Pilot tests have shown, in a pilot unit to design and manufacture of petroleum-contaminated soil really good cleaning effect, to achieve the purpose of desorption and recovery of the oil in the soil. Best cleaning conditions: the the LAS mass concentration of 2.4 g / L, TX100 concentration of 0.6 g / L, auxiliaries the Na2SiO3 quality concentration of 5 g / L, the solid-liquid ratio of 1 g/20 mL, 75 ° C heating conditions ultrasound 30 min, stirred for 60 min, the removal rate was 65.80%, the contaminated soil TPH content decreased from 18.59% to 6.36%, followed by work on soil bioremediation. Infrared spectrometry and ultraviolet-visible absorption spectroscopy results showed that the The surfactant - chemical heat cleaning petroleum contaminated soil samples, four-polar components of petroleum hydrocarbons, having a certain cleaning effect; the cleaning effect of the pilot test. has reached the pilot test requirements, significantly reduced severe petroleum hydrocarbon contaminants in petroleum-contaminated soil, and verify the papers to establish the reliability of the method of cleaning and to design the feasibility of manufacturing pilot test device for the actual repair of engineering laid a certain foundation.
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