Showing papers on "Wastewater published in 1993"

Constructed Wetlands for Water Quality Improvement

Abstract: General Considerations: Constructed Wetlands: Scientific Foundations are Critical (R. Wetzel). Wastewater Treatment in Constructed Wetlands System Design, Removal Processes, and Treatment Performance (H. Brix). Constructed Wetlands and Aquatic Plant Systems: Research, Design, Operational, and Monitoring Issues (G. Tchobanoglous). Wetlands for Wastewater Treatment: Performance Database (R. Knight, R. Kadlec, and S. Reed). The Use of Constructed Wetlands for Wastewater Treatment and Recycling (R. Bastian and D. Hammer). Constructed Wetlands Experience in the Southeast (R. Freeman, Jr.). Engineering: Hydrological Design of Free Water Surface Treatment Wetlands (R. Kadlec and D. Urban). Hydrogeology and Ground Water Monitoring, Constructed Wetlands System, Perdido Landfill, Escambia County, Florida (P. Dohms). Development of Criteria for the Design and Construction of Engineered Aquatic Treatment Units in Texas (A. Cueto). Engineering and Environmental Assessment of Enhanced Bolsa Chica Wetland (R. Walton, S. Bird, B. Ebersole, and L. Hales). Performance Evaluation of a Closed Ecological Life Support System (CELSS) Employing an Artificially Constructed Wetlands (B. Hilton). Acid Mine: Anoxic Limestone Drains to Enhance Performance of Aerobic Acid Drainage Treatment Wetlands: Experiences of the Tennessee Valley Authority (C. Brodie, C. Britt, T. Tomaszewski, and H. Taylor). Storm Event Effects on Constructed Wetlands Discharges (H. Taylor, K. Choate, and G. Brodie). Wetland Water Treatment Systems (S. Witthar). Staged, Aerobic Constructed Wetlands to Treat Acid Drainage: Case History of Fabius Impoundment 1 and Overview of the Tennessee Valley Authority's Program (G. Brodie). Successful Acid Mine Drainage and Heavy Metal Site Bioremediation (J. Davison). The Use of Wetland Treatment to Remove Trace Metals from Mine Drainage (P. Eger, G. Melchert, D. Antonson, and J. Wagner). A Comparison of Local Waste Materials for Sulfate Reducing Wetlands Substrate (M. Gross, S. Formica, L. Gandy, and J. Hestir). Contaminant Removal Capabilities of Wetlands Constructed to Treat Coal Mine Drainage (R. Hedin and R. Nairn). A Peat/Wetland Treatment Approach to Acidic Mine Abatement (T. Frostman). Subsurface Treatment: The Use of Reed Bed Systems to Treat Domestic Sewage: The European Design and Operations Guidelines for Reed Bed Treatment Systems (P. Cooper). Sustainable Suspended-Solids Accumulation in a Gravel Bed Treatment Wetland (R. Kadlec and J. Watson). Gravel Bed Hydroponic Sewage Treatment: Performance and Potential (J. Butler, M. Ford, E. May, R. Ashworth, and J. Williams). The Purification Efficiency of the Planted Soil Filter in See (R. Netter). Constructed Wetlands for Wastewater Treatment in Czechoslovakia: State of the Art (J. Vymazal). Subsurface Flow Wetlands at Mesquite Nevada (C. Lekven, R. Crites, and R. Beggs). Chemical Processes: Efficient Phosphorus Retention in Wetlands: Fact or Fiction? (C. Richardson and C. Craft). Fate of Non-Point Source Nitrate Loads in Freshwater Wetlands: Results from Experimental Wetland Mesocosms (W. Crumpton, T. Isenhart, and S. Fisher). Mechanisms of Wetland-Water Quality Interaction (C. Johnston). Pilot-Scale Nitrification Studies Using Vertical-Flow and Shallow Horizontal-Flow Constructed Wetland Cells (J. Watson and A. Danzig). Phosphorus Removal from Wastewater in a Constructed Wetland (T. Davies and P. Cottingham). Nitrogen and Phosphorus Reduction in Secondary Effluent Using a 15-Acre, Multiple-Celled Reed Canarygrass (Phlaris aruninacea) Wetland (S. Geiger, J. Luzier, and J. Jackson). Water Supply System Utilizing the Edaphic-Phytodepuration Technique (E.S. Manfrinato, E.S. Filho, and E. Salati). Point and Non-Point Sources: Treating Livestock Wastewaters with Constructed Wetlands (D. Hammer, B. Pullin, T. McCaskey, J. Eason, and V. Payne). Evaluation of Aquatic Plants for Constructed Wetlands (D. Surrency). Controlling Agricultural Runoff by Use of Constructed Wetlands (M. Higgins, C. Rock, R. Bouchard, and B. Wengrezynek). Constructed Wetlands R & D Facility at TVA's National Fertilizer and Environmental Research Center (C. Breed). Stormwater Runoff Detention and Renovation: A Backlot Function or Integral Part of the Landscape? (D. Ferlow). Hydrophyte Considerations: Wetland Systems and Their Response to Management (G. Gunterspergen, J. Keough, and J. Allen). Macrophyte Mediated Oxygen Transfer in Wetlands: Transport Mechanisms and Rates (H. Brix). Control of Algae Using Duckweed (lemna) Systems (S. Hancock and L. Buddhavarapu). The Use of Typha latifoua for Heavy Metal Pollution Control in Urban Wetlands (R. Shutes, J. Ellis, D. Revitt, and T. Zhang). Growth of Soft-Stem Bulrush (Scirpus validus) Plants in a Gravel-Based Subsurface Flow Constructed Wetland (M. Edwards, K. Brinkmann, and J. Watson). Species-Specific Aeration of Water by Different Vegetation Types in Constructed Wetlands (E. Stengel). Industrial Applications: Paper Pulp. Performance of a Constructed Marsh in the Tertiary Treatment of Bleach Kraft Pulp Mill Effluent: Results of a Two Year Pilot Project (R. Tettleton, F. Howell, and R. Reaves). The Feasibility of Treating Pulp Mill Effluent with Constructed Wetlands (R. Thut). Testing Color Removal from Pulp Mill Wastewaters with Constructed Wetlands (D. Hammer, B. Pullin, D. McMurry, and J. Lee). Microbial Populations and Decomposition Activity in Three Subsurface Flow Constructed Wetlands Systems (K. Hatano, C. Trehin, C. House, and A. Wollum). Interfacing Constructed Wetlands with Traditional Wastewater Biotreatment Systems (J. Boyd, O. McDonald, D. Hatcher, R. Portier, and R. Conway). Landfill Leachate. Effect of Season, Substrate Composition, and Plant Growth on Landfill Leachate Treatment in a Constructed Wetland (J. Surface, J. Peverly, T. Steenhuis, and W. Sanford). Mitigation of Landfill Leachate Incorporating In-Series Constructed Wetlands of a Closed-Loop Design (C. Martin, G. Moshiri, and C. Miller). Innovative Marsh Treatment Systems for Control of Leachate and Fish Hatchery Wastewaters (R. Hunter, A. Birkbeck, and G. Coombs). Petro Chemical. Constructed Wetlands for Wastewater Treatment at Amoco Oil Company's Mandan, North Dakota Refinery (D. Litchfield). Small Systems: Small Constructed Wetlands Systems for Domestic Wastewater Treatment and Their Performance (G. Steiner and D. Combs). General Design, Construction, and Operation Guidelines for Small Constructed Wetlands Wastewater Treatment Systems (J. Watson and K. Choate). TVA's Constructed Wetlands Demonstration (K. Choate, J. Watson, and G. Steiner). Reed Bed Treatment for Small Communities: U.K. Experience (B. Green and J. Upton). The Treatment of Septage Using Natural Systems (M. Ogden). Constructed Wetlands Wastewater Quality Improvement at Lynnvalle Elementary School (T. Terry). Biological Sludge Drying in Constructed Wetlands (S. Nielsen). Case Studies: Constructed Open Surface Wetlands: The Water Quality Benefits and Wildlife Benefits, City of Arcata, California (R. Gearhart and M. Higley). Constructed Wastewater Wetlands: The Answer in South Dakota's Challenging Environment (J. Dornbush). Application of Constructed Wetlands to Treat Wastewaters in Australia (T. Davies, P. Cottingham, and B. Hart). Creating a Wetlands Wildlife Refuge from a Sewage Lagoon (R. Lofgren). Production and Suppression of Mosquitos in Constructed Wetlands (K. Tennessen). The Integration of Seaweed Biofilters with Intensive Fish Ponds to Improve Water Quality and Recapture Nutrients (A. Neori). Treating Intensive Aquaculture Recycled Water with an Artificial Wetlands Filter System (W. Zachritz and R. Jacquez).

Hazards from pathogenic microorganisms in land-disposed sewage sludge.

Abstract: Sewage sludge is a complex mixture of organic and inorganic compounds of biological and mineral origin that are precipitated from wastewater and sewage during primary, secondary, and tertiary sewage treatment. Present in these sludges are significant numbers of microorganisms that include viral, bacterial, protozoan, fungal, and helminth pathogens. The treatment of sludge to reduce biochemical oxygen demand, solids content, and odor is not always effective in reducing numbers of pathogens. This becomes a public health concern because the infectious dose for some of these pathogens may be as low as 1 particle (virus) to 50 organisms (Giardia). When sludge is applied to land for agricultural use and landfill compost, these pathogens can survive from days (bacteria) to months (viruses) to years (helminth eggs), depending on environmental conditions. Shallow aquifers can become contaminated with pathogens from sludge and, depending on groundwater flow, these organisms may travel significant distances from the disposal site. Communities that rely on groundwater for domestic use can become exposed to these pathogens, leading to a potential disease outbreak. Currently, methods to determine the risk of disease from pathogens in land-disposed sludge are inadequate because the sensitivity of pathogen detection is poor. The application of recombinant DNA technology (gene probes and polymerase chain reaction) to environmental samples may provide increased sensitivity for detecting specific pathogens in land-disposed sludge and greatly improved risk assessment models for our exposure to these sources of pathogens.

A novel membrane bioreactor for detoxifying industrial wastewater: I. Biodegradation of phenol in a synthetically concocted wastewater

Abstract: A novel process has been used to biodegrade phenol present in an acidic (1 M HCI) and salty (5% w/w NaCl) synthetically bioreactor, in which the phenol present in the wastewater is separated from the inorganic components by means of a silicone rubber membrane. Transfer of the phenol from the wastewater and into a biological growth medium allows biodegradation to proceed under controlled conditions which are unaffected by the hostile inorganic composition of the wastewater. At a wastewater flow rate of 18 mL h(-1) (contact time 6 h), 98.5% of the phenol present in the wastewater at an inlet concentration of 1000 mg ((-1)) was degraded; at a contact time of 1.9 h, 65% of the phenol was degraded. Phenol degradation was accompanied by growth of a biofilm on the membrane tubes and by conversion of approximately 80% of the carbon entering the system to CO(2) carbon. Analysis of the transport of phenol across the membrane revealed that the major resistance to mass transfer arose in the diffusion of phenol across the silicone rubber membrane. A mathematical model was used to describe the transfer of phenol across the membrane and the subsequent diffusion and reaction of phenol in the biofilm attached to the membrane tube. This analysis showed that (a) the attached biofilm significantly lowers the mass transfer driving force for phenol across the membrane, and (b) oxygen concentration limits the phenol degradation rate in the biofilm. These conclusions from the model are consistent with the experimental results.

Treatment of highly colored wastewaters

Abstract: The invention is a process for purifying wastewater containing organic and color-causing pollutants. The three unit processes include a first stage aerobic or anaerobic biophysical treatment, a second stage oxidizer treatment, and a third stage adsorbent contact treatment. The biophysical treatment removes the majority of the pollutants while the oxidizer treatment destroys residual organics and color-causing pollutants. The adsorbent contact treatment destroys any residual oxidizer in the wastewater and/or adsorbs any residual oxidation products. The preferred adsorbent is powdered activated carbon and the preferred oxidizer is some form of chlorine, e.g. sodium hypochlorite. The process may be operated in either a continuous flow mode or a batch flow mode.

A novel membrane bioreactor for detoxifying industrial wastewater: II. Biodegradation of 3‐chloronitrobenzene in an industrially produced wastewater

Abstract: A novel membrane bioreactor has been used for the treatment of an industrially produced wastewater arising in the manufacture of 3-chloronitrobenzene. This wastewater is not amenable to direct biological treatment without some form pretreatment or dilution, due to the inorganic composition (pH <1, salt concentration 4% w/w) of the wastewater. In the membrane bioreactor, the organic pollutants are first separated from the wastewater by selective membrane permeation, and then biodegraded in the biological growth compartment of the bioreactor. At a wastewater flow rate of 64 mL h−1 (corresponding to a contact time of approximately 1.7 hours) over 99% of the 3-chloronitrobenzene and over 99% of the nitrobenzene in the wastewater were degraded. Degradation of 3-chloronitrobenzene was accompanied by evolution of chloride ions in a stoichiometric ratio. Both 3-chloronitrobenzene and nitrobenzene degradation were accompanied by the evolution of carbon dioxide; approximately 80% of the carbon entering the system was oxidized to CO2 carbon. Analysis of mass transport across the membrane revealed that 3-chloronitrobenzene and nitrobenzene are transported more rapidly than phenol. This is explained in terms of a resistances-in-series model, which shows phenol transfer to be rate limited by the membrane diffusion step, whereas the chloronitrobenzene and nitrobenzene transfer are rate limited by the liquid film mass transfer. © 1993 Wiley & Sons, Inc.

Ultraviolet disinfection for wastewater reclamation and reuse subject to restrictive standards

Abstract: An ultraviolet (UV) disinfection system was operated under field conditions using both unfiltered and filtered secondary wastewater effluents to assess the feasibility of using UV light to meet the stringent criterion specified in the California Wastewater Reclamation Criteria (CWRC). In the unfiltered wastewater, the CWRC criterion that the 7-day median not exceed 23 total coliform/100 mL was met consistently in effluent exposed to an average UV dose of 60 mW.s/cm 2 or greater. In the filtered wastewater, the CWRC criterion that the 7-day median not exceed 23 total coliform/100 mL was met consistently in effluent exposed to an average UV dose of 48 mW.s/cm 2 or greater.

Retention of nutrients and heavy metals in mangrove sediment receiving wastewater of different strengths

Abstract: Column leaching experiments were conducted to assess the retention of nutrients and heavy metals in mangrove sediments receiving wastewater of different strengths. The amounts of pollutants retained in the sediments increased with the strength of wastewater. The sediments leached with the strongest wastewater had the highest concentration of NH4+‐N, NO3 ‐‐N, P, Cu, Mn, Zn and Cd. Most of the retained wastewater‐borne pollutants were concentrated in the first 4 cm of the sediment column, with very little downwards migration. This suggests that the mangrove sediments acted as an efficient trap for immobilization of nutrients (in particular P) and heavy metals.

N-chloroaldimines. 3. Chlorination of phenylalanine in model solutions and in a wastewater

Abstract: The chlorination reactions of valine in water and wastewater were studied. N-Chlorovaline and isobutyraldehyde were the main products at Cl/N molar ratios of <1, while isobutyronitrile and N-chloroisobutyraldimine were the major products at Cl/N ratios of 2.0 and beyond. N-Chloroisobutyraldimine was identified by gas chromatography/mass spectroscopy and infrared and nuclear magnetic resonance spectroscopy. The concentration of valine in a primary municipal wastewater effluent was determined. The amounts and identity of its chlorination products in wastewater were determined by using a radiotracer and were found to be similar to those found in the model solutions.

Stripping of volatile organic compounds at full-scale municipal wastewater treatment plants

Abstract: A field investigation was carried out at four Ontario municipal wastewater treatment plants to characterize stripping of volatile organic compounds (VOCs) from aerated process vessels. Concentrations of VOCs in the off-gas and wastewater at aerated grit chambers and aeration basins were measured. Thirty-two of 36 target VOCs were observed in at least one off-gas sample from the plants studied. The total emissions for the measured compounds ranged from 2 700 to 3 900 g/d or 36 to 50 g/1000 m 3 of wastewater treated. Chlorinated VOCs tended to be stripped to a greater extent than nonchlorinated compounds. The data suggest that VOC stripping can be reduced by reducing aeration rates, and that operating and design parameters have an impact on the loss of VOCs

Process for brine disposal

Abstract: A method of treating and disposing of waste water containing salt, such as the brine that results from production of oil and/or gas wells, which includes introducing the waste water into a reverse osmosis unit to produce concentrated brine, and passing the concentrated brine through a combustion heat evaporator wherein said combustion heat is generated in a submerged combustion evaporator or exhaust gases from an internal combustion engine to power a waste heat evaporator to produce a further concentrated brine. The concentrated brine from the combustion heat evaporator can then be mixed with a liquid such as the waste water that is introduced into the reverse osmosis unit. The resulting product can then be injected into a subterranean formation for purposes of disposal. The method allows the volume of the waste water to be significantly reduced while also increasing the salt concentration of the waste water. In other embodiments the reverse osmosis unit and the combustion heat evaporator are used individually. Alternatively, the concentrated brine from the combustion heat evaporator can be introduced into a dryer to evaporate water from the concentrated brine to produce low moisture salt particles.

Volatile Flavor Components in Snow Crab Cooker Effluent and Effluent Concentrate

Abstract: Volatile compounds in snow crab cooker effluent (SCCE) and effluent concentrate (EC) were compared by simultaneous steam distillation-solvent extraction/gas chromatography/mass specirometry (SDE/GC/ MS). Volatile compounds (122) were detected in both samples. Of these, 97 were positively identified, composed mainly of nitrogen-and sulfur-containing compounds, aromatic hydrocarbons, aldehydes, ketones, furans, and alcohols. A total of 101 compounds were detected in the cooker effluent, and 90 were detected in the concentrate. Amounts of sulfur- and nitrogen-containing compounds were 44 and 7.3 times higher, respectively, in EC.

Remove organics by activated carbon adsorption

Abstract: Activated carbon has a wide variety of applications in the chemical process industries (CPI), one of which is water and wastewater treatment. Activated carbon is especially effective at removing soluble organic compounds (SOCs) from both surface and groundwater sources. This article focuses on the use of granular activated carbon to remove specific compounds from water sources. It provides a methodology to evaluate adsorption, establish a process design, develop a system design, and estimate preliminary capital and operating costs.

LAS homolog distribution shift during wastewater treatment and composting: Ecological implications

Abstract: The behavior of LAS (linear alkylbenzene sulfonate) in different environmental compartments was studied through wastewater treatment process steps in sewage treatment plants of Alicante and Benidorm (activated sludge type) as well as in Guardamar (lagoons). The fate of LAS, using a specific HPLC method, was monitored during treatment sludge compostage and soil amendment operations. Finally, the marine sediments close to a submarine wastewater sewer outfall were analyzed. The results show significant differences between distribution of LAS homologs in water and solids (sludges, sediments, and soils), as compared to the original distribution in detergent formulations, yielding a lower LAS average molecular weight in water samples. The change observed in the homolog distribution of LAS implies a reduction in the toxicity to Daphnia, because a lower average molecular weight of LAS is less toxic.