The effects of air flow rate, media size and sparge point size on volumetric water content and bulk density during air sparging /
A laboratory study was developed to examine the effects of air flow rate, media size and sparge point size on volumetric water content and bulk density. Data were collected from a series of two dimensional tests using dual gamma attenuation. Bulk density and water content were measured at three dif...
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
1996.
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| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=743273031&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | A laboratory study was developed to examine the effects of air flow rate, media size and sparge point size on volumetric water content and bulk density. Data were collected from a series of two dimensional tests using dual gamma attenuation. Bulk density and water content were measured at three different air flow rates, 1, 4, and 9 LPM as well as the no flow condition. Three graded Brady sands, 12-20, 16-30 and 20-40, were used as the porous media. Three sparge points were used. Two sparge points were constructed from 12.70 mm pipe with 1.6 mm and 0.71 mm holes. The third sparge point was a commercially available microporous sparge point .Two analyses were conducted on the data. First, the spatial correlations of volumetric water content and bulk density were determined in both the horizontal and vertical directions. The data appeared anisotropic for water content at the no flow state but, became more isotropic as air flow was started. The lag correlations decreased as separation distance increased and as air flow rate increased for water content. Bulk density was only slightly correlated and appeared to be affected most by the sand size and initial tank packing. The second analysis was an anajysis of tank packing. The second analysis was an anajysis of was significantly affected by air flow rate, sand size, and sparge point size. Air flow rate was the most significant factor, as flow rate increased water content decreased. The flow rate was not a significant factor affecting bulk density but sand size and sparge point were slightly significant. Bulk density was most variable with smaller sands and with the 1.6 mm and microporous sparge points. This research indicates that channeling during air sparging might be reduced by using lower flow rates and small discrete air bubbles. Reducing channeling will improve contaminant mass transfer efficiency by reducing the dependence on as a major diffusion transport mechanism. |
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| Item Description: | Vita. "Major Subject: Agricultural Engineering". |
| Physical Description: | xiii, 280 leaves : illustrations, maps ; 28 cm. Issued also on microfiche from University Microfilms Inc. |
| Bibliography: | Includes bibliographical references. |