page 451 |
Previous | 1 of 8 | Next |
|
|
Loading content ...
ADSORPTION OF HEAVY METALS WITH INERT BIOLOGICAL SLUDGES AT NEUTRAL PH'S Roque A. Roman-Seda, Assistant Professor Department of Civil Engineering University of Puerto Rico Mayaguez, Puerto Rico 00708 INTRODUCTION This work tried to ascertain what ordinary secondary sludges can do to remove dissolved heavy metals from wastewaters at neutral pH's. The long range goal of the study was to assess the feasibility of developing a new technology for the removal of heavy metals from wastewaters utilizing biological sludges as adsorbers. A secondary but nonetheless important motivation was to create a useful application for an unwanted by-product of wastewater treatment. The short term goal of the project was to estimate the potential of inert biological sludges for the removal of heavy metals at neutral pH's under batch conditions. It is important that the adsorber perform well at or near the pH region at which it would be used in order to avoid the costly addition of chemicals, thus making the new technology cost attractive. PREVIOUS WORK Microorganisms have been shown to concentrate cations from their aquatic environment and, specifically, to concentrate heavy metal ions. Beveridge et al [1] has shown this phenomenon for Bacillus subtilis in particular and for bacterial cell walls in general [2]. Chio [3] documented the uptake of heavy metals by microbes. Elsabee et al [4] illustrated the relationship between cupric complexes and cell wall related structures. Paskins-Hurlburt et al [5] documented the relationship between biosorption of lead and a specific kind of microorganism. Volesky et al [6] showed that biosorbent activity is not associated exclusively with living organisms but that it is present in dead biomass as well to perhaps an even greater degree. Biosorption has been specifically linked to the cell wall. Volesky [7] and other workers [8,9,10] have gone beyond and demonstrated the feasibility of concentrating uranium, thorium, actinides and other valuable heavy metals from dilute radioactive wastes or seawater by using pure cultures of microorganisms that selectively remove these metals. The work done so far suggests that this biosorption property should be present in wastewater sludges and that, therefore, these may be useful in sequestering heavy metals from wastewaters. It is the intent of this work to investigate such a connection and to elucidate some of the parameters that enhance the biosorption phenomenon. OBJECTIVES The objectives of this study were: 1) To determine whether there exists in biological sludges a significant biosorption capacity for the removal of cadmium, lead, nickel, and chromium; and 2) To determine the effects of the operational parameters of contact time, sludge concentration, and initial metal concentration on overall removal. EXPERIMENTAL PROCEDURE A source of dried, stabilized sludge was selected from a municipal wastewater treatment plant. Information was collected on the operational characteristics of the plant and on the wet sludge characteristics before it was dried. 451
Object Description
Purdue Identification Number | ETRIWC198545 |
Title | Adsorption of heavy metals with inert biological sludges at neutral pH's |
Author | Roman-Seda, Roque A. |
Date of Original | 1985 |
Conference Title | Proceedings of the 40th Industrial Waste Conference |
Conference Front Matter (copy and paste) | http://e-archives.lib.purdue.edu/u?/engext,36131 |
Extent of Original | p. 451-458 |
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 | 2009-07-15 |
Capture Device | Fujitsu fi-5650C |
Capture Details | ScandAll 21 |
Resolution | 300 ppi |
Color Depth | 8 bit |
Description
Title | page 451 |
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 | ADSORPTION OF HEAVY METALS WITH INERT BIOLOGICAL SLUDGES AT NEUTRAL PH'S Roque A. Roman-Seda, Assistant Professor Department of Civil Engineering University of Puerto Rico Mayaguez, Puerto Rico 00708 INTRODUCTION This work tried to ascertain what ordinary secondary sludges can do to remove dissolved heavy metals from wastewaters at neutral pH's. The long range goal of the study was to assess the feasibility of developing a new technology for the removal of heavy metals from wastewaters utilizing biological sludges as adsorbers. A secondary but nonetheless important motivation was to create a useful application for an unwanted by-product of wastewater treatment. The short term goal of the project was to estimate the potential of inert biological sludges for the removal of heavy metals at neutral pH's under batch conditions. It is important that the adsorber perform well at or near the pH region at which it would be used in order to avoid the costly addition of chemicals, thus making the new technology cost attractive. PREVIOUS WORK Microorganisms have been shown to concentrate cations from their aquatic environment and, specifically, to concentrate heavy metal ions. Beveridge et al [1] has shown this phenomenon for Bacillus subtilis in particular and for bacterial cell walls in general [2]. Chio [3] documented the uptake of heavy metals by microbes. Elsabee et al [4] illustrated the relationship between cupric complexes and cell wall related structures. Paskins-Hurlburt et al [5] documented the relationship between biosorption of lead and a specific kind of microorganism. Volesky et al [6] showed that biosorbent activity is not associated exclusively with living organisms but that it is present in dead biomass as well to perhaps an even greater degree. Biosorption has been specifically linked to the cell wall. Volesky [7] and other workers [8,9,10] have gone beyond and demonstrated the feasibility of concentrating uranium, thorium, actinides and other valuable heavy metals from dilute radioactive wastes or seawater by using pure cultures of microorganisms that selectively remove these metals. The work done so far suggests that this biosorption property should be present in wastewater sludges and that, therefore, these may be useful in sequestering heavy metals from wastewaters. It is the intent of this work to investigate such a connection and to elucidate some of the parameters that enhance the biosorption phenomenon. OBJECTIVES The objectives of this study were: 1) To determine whether there exists in biological sludges a significant biosorption capacity for the removal of cadmium, lead, nickel, and chromium; and 2) To determine the effects of the operational parameters of contact time, sludge concentration, and initial metal concentration on overall removal. EXPERIMENTAL PROCEDURE A source of dried, stabilized sludge was selected from a municipal wastewater treatment plant. Information was collected on the operational characteristics of the plant and on the wet sludge characteristics before it was dried. 451 |
Resolution | 300 ppi |
Color Depth | 8 bit |
Tags
Comments
Post a Comment for page 451