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Paper Chromatographic Method for Volatile Acids HI — Toxicity of Propionic Acid A. M. BUSWELL, Consultant University of Florida Gainesville, Florida G. B. MORGAN, Assistant Research Professor Department of Civil Engineering University of Florida Gainesville, Florida In the various studies of the fermentation which occurs during the biological stabilization of organic matter, especially as it occurs in the digestion of sewage sludge, the following substances have been observed to varv with the conditions and completeness of the process. These substances may be divided into three classes; namely, gases, substances dissolved in the liquor, and the biota. The gases qualitatively consist of methane, carbon dioxide and smaller amounts of hydrogen. Under adverse conditions, the gases may consist of hydrogen and carbon dioxide but little or no methane. Quantitatively, the yield of gas amounts to about 10 cf per lb volatile matter under good conditions and the gas is composed of about 65 per cent methane and 35 per cent CO2 (excluding N2). In extremely poor conditions, the amount of gas decreases to less than one cf per lb organic matter, composed of approximately 2/3 CO2 and 1/3 hydrogen. Of the substances in solution, considerable data are available on the volatile acids, alkalinity, ammonia, and pH. Qualitatively, the volatile acids have been considered to consist mainly of acetic. Recent research, including the material presented herewith, reveals the importance of the other acids. Quantitatively, the volatile acid content remains low and stable during good digestion but increases rapidly as an indication of the introduction of inhibiting factors. Alkalinity, depending as it does largely on CaC03 or Ca(HC03)2 may remain constant at a value determined by the character of the local water supply or, as is usually the case in domestic wastes, the alkalinity may increase due to ammonalysis of nitrogenous matter. If however the production of methane is inhibited, the volatile acids accumulate until they exceed the alkalinity. By this time gas production including the H2-CO2 phase has practically ceased and in most cases cannot be reestablished. The pH, as is evident from the above discussion, does not drop until the volatile acids have accumulated to a value exceeding the various buffers including the volume or dilution effect. When this occurs all fermentation is arrested. - 377 -
Object Description
Purdue Identification Number | ETRIWC196233 |
Title | Paper chromatographic method for volatile acids iii -toxicity of propionic acid |
Author |
Buswell, Arthur M. (Arthur Moses), 1888- Morgan, George B. |
Date of Original | 1962 |
Conference Title | Proceedings of the seventeenth Industrial Waste Conference |
Conference Front Matter (copy and paste) | http://earchives.lib.purdue.edu/cdm4/document.php?CISOROOT=/engext&CISOPTR=9369&REC=10 |
Extent of Original | p. 377-388 |
Collection Title | Engineering Technical Reports Collection, Purdue University |
Repository | Purdue University Libraries |
Rights Statement | Digital object copyright Purdue University. All rights reserved. |
Language | eng |
Type (DCMI) | text |
Format | JP2 |
Date Digitized | 2009-05-18 |
Capture Device | Fujitsu fi-5650C |
Capture Details | ScandAll 21 |
Resolution | 300 ppi |
Color Depth | 8 bit |
Description
Title | page 377 |
Collection Title | Engineering Technical Reports Collection, Purdue University |
Repository | Purdue University Libraries |
Rights Statement | Digital object copyright Purdue University. All rights reserved. |
Language | eng |
Type (DCMI) | text |
Format | JP2 |
Capture Device | Fujitsu fi-5650C |
Capture Details | ScandAll 21 |
Transcript | Paper Chromatographic Method for Volatile Acids HI — Toxicity of Propionic Acid A. M. BUSWELL, Consultant University of Florida Gainesville, Florida G. B. MORGAN, Assistant Research Professor Department of Civil Engineering University of Florida Gainesville, Florida In the various studies of the fermentation which occurs during the biological stabilization of organic matter, especially as it occurs in the digestion of sewage sludge, the following substances have been observed to varv with the conditions and completeness of the process. These substances may be divided into three classes; namely, gases, substances dissolved in the liquor, and the biota. The gases qualitatively consist of methane, carbon dioxide and smaller amounts of hydrogen. Under adverse conditions, the gases may consist of hydrogen and carbon dioxide but little or no methane. Quantitatively, the yield of gas amounts to about 10 cf per lb volatile matter under good conditions and the gas is composed of about 65 per cent methane and 35 per cent CO2 (excluding N2). In extremely poor conditions, the amount of gas decreases to less than one cf per lb organic matter, composed of approximately 2/3 CO2 and 1/3 hydrogen. Of the substances in solution, considerable data are available on the volatile acids, alkalinity, ammonia, and pH. Qualitatively, the volatile acids have been considered to consist mainly of acetic. Recent research, including the material presented herewith, reveals the importance of the other acids. Quantitatively, the volatile acid content remains low and stable during good digestion but increases rapidly as an indication of the introduction of inhibiting factors. Alkalinity, depending as it does largely on CaC03 or Ca(HC03)2 may remain constant at a value determined by the character of the local water supply or, as is usually the case in domestic wastes, the alkalinity may increase due to ammonalysis of nitrogenous matter. If however the production of methane is inhibited, the volatile acids accumulate until they exceed the alkalinity. By this time gas production including the H2-CO2 phase has practically ceased and in most cases cannot be reestablished. The pH, as is evident from the above discussion, does not drop until the volatile acids have accumulated to a value exceeding the various buffers including the volume or dilution effect. When this occurs all fermentation is arrested. - 377 - |
Resolution | 300 ppi |
Color Depth | 8 bit |
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