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ANAEROBIC EXPANDED BED TREATMENT OF WHEY Michael S. Switzenbaum, Assistant Professor Department of Civil and Environmental Engineering Clarkson College of Technology Potsdam, New York 13676 Scott C. Danskin, Environmental Engineer Airco Carbon Niagara Falls, New York 14302 Whey, a green-yellow liquid, is a by-product of all cheese production. Each pound of cheese produced results in five to ten pounds of fluid whey. In the United States, approximately 37x10 pounds of whey are produced each year [ 1 ]. The high organic content of whey leads to a severe disposal problem. The BOD of whey ranges from 32,000 to 60,000 mg/l [2]. Every 1000 gallons per day of raw whey discharged into a sewage treatment plant can impose a load equal to that from 1800 people. Thus, whey is produced in large volumes with a high organic content. Whey can be thought of as a resource awaiting discovery. It has a high content of lactose and protein. Over the recent past, several investigations have developed new schemes of whey treatment with the emphasis on product recovery and new product development. Among these efforts have been fermentation of whey to ethanol for beverage production [ 1], or gasohol production [3]; drying of whey into powder which may be used as animal feed or as a supplement in human foods [4]; separation of whey components by membrane technology [2]; and fermentation of whey for protein production [5]. Many of these schemes, however, are limited to larger dairy producers due to economic constraints. At this point whey is still a significant waste problem necessitating proper treatment. The types of waste treatment methods used in the dairy food industry are primarily activated sludge, trickling filter, aerated lagoons, irrigation and a combination of these processes. Another waste treatment alternative which has only been used sparsely is the anaerobic process. Anaerobic processes were at one time used in the septic tank treatment of the waste from very small dairies. As these dairies grew, most turned to aeration, then conventional activated sludge units. However, the few reports of anaerobic treatment of dairy waste have shown that theprocess can obtain good treatment efficiencies using conventional, contact, and fixed film processes [6-10]. Anaerobic treatment offers several advantages over aerobic processes [11], such as (a) a higher degree of waste stabilization; (b) a lower microbial yield; (c) a lower nutrient requirement; (d) no oxygen requirement; and (e) methane gas production. With regard to anaerobic treatment of whey, these advantages are pronounced since whey constitutes a high organic loading which is often deficient in nutrients. In addition, the methane produced, a high quality automatically separated form of energy, can be used at the cheese production plant for heating and cooking (i.e. a ready market demand at its source of production). It represents a significant resource recovery. Thus anaerobic fermentation offers a dual benefit to cheese manufacturers—energy production and pollution control. Yet, it is used only sparsely for the treatment of whey. This most likely is a result of the general feeling of unreliability anaerobic processes receive due to several limitations commonly associated with the process. Foremost are the temperature requirements of 35 C for efficient treatment and lack of stability following changes in 414
Object Description
Purdue Identification Number | ETRIWC198144 |
Title | Anaerobic expanded bed treatment of whey |
Author |
Switzenbaum, Michael S. Danskin, Scott C. |
Date of Original | 1981 |
Conference Title | Proceedings of the 36th Industrial Waste Conference |
Conference Front Matter (copy and paste) | http://earchives.lib.purdue.edu/u?/engext,32118 |
Extent of Original | p. 414-424 |
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 | 2009-07-07 |
Capture Device | Fujitsu fi-5650C |
Capture Details | ScandAll 21 |
Resolution | 300 ppi |
Color Depth | 8 bit |
Description
Title | page 414 |
Collection Title | Engineering Technical Reports Collection, Purdue University |
Repository | Purdue University Libraries |
Rights Statement | Digital copyright Purdue University. All rights reserved. |
Language | eng |
Type (DCMI) | text |
Format | JP2 |
Capture Device | Fujitsu fi-5650C |
Capture Details | ScandAll 21 |
Transcript | ANAEROBIC EXPANDED BED TREATMENT OF WHEY Michael S. Switzenbaum, Assistant Professor Department of Civil and Environmental Engineering Clarkson College of Technology Potsdam, New York 13676 Scott C. Danskin, Environmental Engineer Airco Carbon Niagara Falls, New York 14302 Whey, a green-yellow liquid, is a by-product of all cheese production. Each pound of cheese produced results in five to ten pounds of fluid whey. In the United States, approximately 37x10 pounds of whey are produced each year [ 1 ]. The high organic content of whey leads to a severe disposal problem. The BOD of whey ranges from 32,000 to 60,000 mg/l [2]. Every 1000 gallons per day of raw whey discharged into a sewage treatment plant can impose a load equal to that from 1800 people. Thus, whey is produced in large volumes with a high organic content. Whey can be thought of as a resource awaiting discovery. It has a high content of lactose and protein. Over the recent past, several investigations have developed new schemes of whey treatment with the emphasis on product recovery and new product development. Among these efforts have been fermentation of whey to ethanol for beverage production [ 1], or gasohol production [3]; drying of whey into powder which may be used as animal feed or as a supplement in human foods [4]; separation of whey components by membrane technology [2]; and fermentation of whey for protein production [5]. Many of these schemes, however, are limited to larger dairy producers due to economic constraints. At this point whey is still a significant waste problem necessitating proper treatment. The types of waste treatment methods used in the dairy food industry are primarily activated sludge, trickling filter, aerated lagoons, irrigation and a combination of these processes. Another waste treatment alternative which has only been used sparsely is the anaerobic process. Anaerobic processes were at one time used in the septic tank treatment of the waste from very small dairies. As these dairies grew, most turned to aeration, then conventional activated sludge units. However, the few reports of anaerobic treatment of dairy waste have shown that theprocess can obtain good treatment efficiencies using conventional, contact, and fixed film processes [6-10]. Anaerobic treatment offers several advantages over aerobic processes [11], such as (a) a higher degree of waste stabilization; (b) a lower microbial yield; (c) a lower nutrient requirement; (d) no oxygen requirement; and (e) methane gas production. With regard to anaerobic treatment of whey, these advantages are pronounced since whey constitutes a high organic loading which is often deficient in nutrients. In addition, the methane produced, a high quality automatically separated form of energy, can be used at the cheese production plant for heating and cooking (i.e. a ready market demand at its source of production). It represents a significant resource recovery. Thus anaerobic fermentation offers a dual benefit to cheese manufacturers—energy production and pollution control. Yet, it is used only sparsely for the treatment of whey. This most likely is a result of the general feeling of unreliability anaerobic processes receive due to several limitations commonly associated with the process. Foremost are the temperature requirements of 35 C for efficient treatment and lack of stability following changes in 414 |
Resolution | 300 ppi |
Color Depth | 8 bit |
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