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Freshwater isopods (Asellidae) of North America
1972
Williams, W. D. (William David)
Reverse osmosis concentration of dilute pulp & paper effluents
1972
Wiley, Averill J. | Dubey, George A. | Bansal, I. K.
Mine spoil potentials for water quality and controlled erosion
1972
Jencks, Everett M. | Singh, Rabindar N. | Smith, Richard M. | Wilson, Harold A. | Grube, Walter E.
Analysis of exploratory test cores and rock chip samples has made available information necessary to the development of rational techniques for reclaiming coal mine spoil for useful purposes. By assigning an area a particular future use and analyzing the rock structure in advance of the surface mining, materials can be assembled and placed in the fill to allow the filled strip mine to revegetate and be developed into a useful area. Oxidation of pyrite materials, source of most acidity below 4.0 in mine spoils, can be controlled by: (1) using clay shales for fill; (2) controlling gain size in the fill; and (3) controlling accessibility to exchange of solutes and oxygen. In miniature lysimeters filled with 4 ft of normal, loamy (pH 6.7) soil, no acidity nor iron drained from the bottom from pyrite buried at 6 depths, from 1/2 to 36 inches, during a 24 week test period. Base exchange by the soil neutralized the acid and retained the iron.
Afficher plus [+] Moins [-]Joint treatment of municipal sewage and pulp mill effluents
1970 | 1972
Voelkel, K. G. | Deering, R. W. | Wilms, L. R.
The pesticide manufacturing industry--current waste treatment and disposal practices
1972
Atkins, Patrick R.
An in-depth review of the literature, including government information documents, technical reports, the technical journals, industrial publications, and twenty plant interviews with plant managers and operators were used as the data base for studying the 'state of the art' of pesticide manufacturing waste treatment and disposal practices. The report contains chapters dealing with: The present and projected pesticide demands in the United States: The chemistry of pesticides including production processes and waste generation, Waste treatment possibilities discussed in the literature, Pesticide waste treatment systems that have been or currently are in full scale operation, and The cost of pesticide waste treatment system.
Afficher plus [+] Moins [-]Renovating secondary sewage by ground water recharge with infiltration basins
1972
Bouwer, Herman | Rice, R. C. | Escarcega, E. D. | Riggs, M. S.
A field project demonstrated the feasibility of renovating secondary sewage effluent by ground water recharge with infiltration basins. Maximum loading rates were obtained. With the schedules the system could infiltrate 300-400 ft/year using a water depth of 1 ft. Grassed basins had higher infiltration rates, and a gravel covered basin had a lower infiltration rate than a bare soil basin. Essentially complete removal of BOD and fecal coliform, and significant removal of phosphorus, nitrogen and fluoride were obtained. Hydraulic properties of the aquifer were evaluated by analog from the response of piezometric heads in the ground-water system to infiltration. These properties were then used in the design of a prototype system, which would yield renovated water at an estimated total cost of about $5 per acre-foot at the pump.
Afficher plus [+] Moins [-]Continued evaluation of oxygen use in conventional activated sludge processing | Activated sludge processing
1972
McDowell, M. A.
A process (called UNOX) for treating municipal wastewater using high-purity oxygen in the activated sludge process was further evaluated at Batavia, New York in a full scale wastewater treatment plant. The present evaluation places emphasis on the production rate, filtration, and digestion characteristics of oxygenated waste activated sludge. Operation was conducted at two different system loadings over a period of three months. The filtering characteristics of waste activated sludge from an oxygenation system were investigated. Waste activated sludge was aerobically digested in 800-gallon batches using high-purity oxygen. The economics of oxygenation systems as compared with conventional diffused air aeration systems were revised from the cost estimates presented in initial work.
Afficher plus [+] Moins [-]Evaluation of salt water disposal into potential ground-water resources
1972
Norris, Fred A.
Recycle of papermill waste waters and application of reverse osmosis
1972
Morris, David C. | Nelson, William Ralph | Walraven, Gerald O.
Freshwater polychaetes (Annelida) of North America
1972
Foster, Nancy (Nancy Marie)