Showing papers on "Wastewater published in 1969"

Wastewater treatment using electrolysis with activated carbon cathode

Abstract: An improvement in the electrolytic treatment of wastewater is described in which the reduction of oxygen on an activated carbon cathode is employed to form hydrogen peroxide, which in turn serves to oxidize organic carbon pollutants in the wastewater.

Method of treating organic waste water

Abstract: A method of treating organic waste water which comprises the steps of bringing activated sludge consisting mainly of denitrifying bacteria into contact with organic waste water in the presence of nitrate ions or nitrite ions, keeping said waste water in an anaerobic state and destroying the decomposable organic matters contained in the waste water by virtue of the nitrate respiration of said denitrifying sludge.

Process for treating sewage and other contaminated waters

Abstract: SEWAGE AND OTHER CHEMICALLY IMPURE WATERS ARE MADE CLEANER BY A PROCESS WHICH INVOLVES THE REMOVAL OR EXTRACTION FROM THE WATER OF VARIOUS CONTAIMINANTS BY THE CONTROLLED GROWTH OF SELECTED MICROORGANISMS USING THE SEWAGE OR OTHER IMPURE WATER AS THE BASIC GROWTH SUBSTRATE. THE MICROORGANISMS (BOTH AS THE INOCULANT AND AS THE GROWTH PRODUCT) ARE ISOLATED FROM THE SEWAGE OR OTHER CONTAMINATED WATER BY MEANS OF A POROUS MEMBRANE OR BARRIER OR RESTRICTED PORE SIZE (E.G. 0.8-2 MICRONS). THESE PORES ARE LARGE ENOUGH TO PERMIT MOLECULES OF THE CONTAMINANTS TO PASS THROUGH OR PENETRATE THE POROUS BARRIER TO THEREBY CONTACT ANDBE ACTED UPON OR ASSIMILATED BY THE MICROORGANISMS. THESE PORES ARE SMALL ENOUGH TO PREVENT THE LARGE SCALE ESCAPE OR MASS MIGRATION OF THE MICROORGANISM THROUGH THE MEMBRANE INTO THE CONTAMINATED WATER. AS A RESULT OF THE PROCESS, ONE OR MORE CONTAMINANTS IN THE WASTE WATER ARE CONSUMED IN THE MICROBIAL METABOLISM OR GROWTH PROCESS, THEREBY MAKING THE WATER CLEANER.

Combined wastewater treatment and power generation

Abstract: Both apparatus and a method for the treatment of domestic wastewater are described. A substantial reduction in refractory nutrient content of such waters is effected by the addition of an electrolyte, if needed, and passage of the wastewater through battery-cell structure having as one electrode thereof a metal the oxide of which, when formed in water, acts as a flocculent. Air introduced into the cell prevents suspended sludge from settling in the cell and provides (or supplements) the depolarizing oxidant. Conduct of the process simultaneously produces direct current electrical power, as well, which may be employed to release chlorine from an aqueous chloride solution for combating pathogenic organisms in the wastewater.

Sewage sludge conditioning and disinfection by gamma irradiation.

Abstract: Nthe treatment of wastewater of either a municipal or industrial origin by means of a gravity separation process followed by a microbiological process, the end result is the creation of a particulate mass suspended in water which is termed sludge. In the case of the gravity separation process the material is termed raw sludge, and in the case of the microbiological process the material is usually called secondary sludge. Raw sludge will usually contain about 2-5 pounds of solids per 100 pounds of mixture while secondary sludge will contain about 0.5-1.0 pounds of solids per 100 pounds of mixture. Since both materials contain putrescible organics, they must be further processed before they can be disposed of in the environment without creating an odor nuisance or a gross watet pollution problem. In addition, the sludges contain significant numbers of coliform organisms and thus are potential sources of pathogens. In most wastewater treatment plants these sludges are mixed and then placed in a unit called a digester where they undergo an anaerobic fermentation process. The digestion process usually employs a 15-to-30-day holding time after which the stabilized sludge must be disposed of in some manner. In some plants the digested sludge is chemically conditioned, vacuum-filtered and the cake buried in a sanitary landfill. In other plants the digested sludge is airdried and the cake buried; in still others the digested sludge is not dewatered but is applied directly to land by tank wagons. This latter means of disposal is only popular with the smaller communities. There are other less used methods of sludge stabilization and handling, but they all employ dewatering and destruction of organic solids at some point in the processing. The fact that sludge stabilization, dewatering, and ultimate disposal constitute as much as 50 per cent of the total cost of wastewater treatment has caused many people to look at what might be -done to lessen the over-all cost. In this respect, the Metropolitan Sanitary District of Greater Chicago was faced with a problem that involved the high cost of sludge handling and disposal, land area for disposal of the dewatered cake, a need for new equipment, and a large expense for replacement of worn-out equipment. To utilize all possible means of solution to the problem of sludge handling and dis-

Sewage treatment system

Abstract: METHOD AND APPARATUS FOR TREATING HOUSEHOLD WASTE WATER WHERIN RAW SEWAGE IS DECOMPOSED WITH AN AEROBIC PROCESS IN A SEPTIC TANK AND CHLORINE IS ADDED TO THE WASTEWATER AFTER IT IS DISCHARGED FROM THE SEPTIC TANK.

High-level inactivation of viruses in wastewater by chlorination.

Abstract: With increasing population density and the prospect of much greater reuse of wastewater, the inactivation of en teroviruses in wastewater effluents has been given a great deal of study dur ing the past 10 yr. It has been determined that over 100 different strains of viruses are excreted in feces by man (1). These include the polio virus, Coxsackie virus A, Coxsackie virus B, echovirus, adenovirus, reo virus, and infectious hepatitus virus. Studies have been made to deter mine the degree of inactivation of en teroviruses in the processes of a waste water treatment plant (2) (3) (4) (5) (6) (7). The results of these studies show that wastewater treatment proc esses do not provide sufficient virucidal capabilities to insure high level inac tivation of enteroviruses. It would appear that the only posi tive way of providing a virus free effluent would be to establish a con scientious program of disinfection. At the present time the primary means of disinfection is by the use of chlorine, either in the gaseous or liquid form. Inactivation of viruses in wastewater

Biological purification of waste water by - the activated sludge process

Abstract: Purification plant comprises an activating tank with a large bypass used as storage tank for long-period activation In the chamber enclosed by the bypass is a secondary settler combined with another tank which is used as collecting vessel for aerobically stabilised sludge It is then used for aerobic sludge stabilisation and finally as intensive activating tank with a special settling section which is placed in front of the activating tank of the bywash

Process for purification of oil production waste water

Abstract: A METHOD FOR REMOVING RESIDUAL OIL AND DISSOLVED SULFIDES FROM OIL PRODUCTION WASTE WATERS PRIOR TO DISPOSAL OF THE WASTE WATER INTO THE OCEAN, BY THE INJECTION OF CONTROLLED AMOUNTS OF AIR AND SOLUBLE NICKEL CATALYST INTO THE WASTE WATER. THE MIXTURE IS PUMPED UNDER PRESSURE INTO A FLOTATION CELL OR TANK WHERE THE PRESSURE IS RELEASED AND THE AIR EFFECTS OIL SEPARATION AND OXIDATION OF THE DISSOLVED HYDROGEN SULFIDE.

Wastewater treatment sequence

Abstract: An improved process for treating wastewater is based on a pre-treatment to convert high molecular weight soluble organic material in raw wastewater into organic material of low molecular weight. Following this conversion, the wastewater is treated with a process sequence tailored to effluent quality requirements. One such sequence may include, for example, the steps of physical or biological adsorption, solids removal, membrane filtration, and disinfection.

Treatment of aqueous streams for removal of nitrogen and phosphorus compounds

Abstract: A PROCESS FOR THE TREATMENT OF AQUEOUS BIOLOGICAL WASTES AND/OR OTHER LIQUIDS CONTAINING POLLUTIONAL MATERIALS TO PRODUCE AN EFFLUENT HAVING A LOW COD (BOD) AND A SUBSTANTIALLY REDUCED CONCENTRATION OF SOLBULE NITROGEN AND PHOSPHORUS COMPOUNDS WHEREIN A WASTE WATER STREAM IS FED TO A COKING ZONE AND HEATED TO A TEMPERATURE IN THE RANGE OF 400 TO 700*F. UNDER SUFFICIENT PRESSURE TO PREVENT THE VAPORIZATION OF WATER TO FORM COKE, CARBON DIOXIDE, AND LOW MOLECULAR WEIGHT OXYGENATED, ORGANIC COMPOUNDS WHICH ARE SEPARATED FROM THE TREATED SEWAGE AQUEOUS EFFLUENT; THIS EFFLUENT IS OXIDIZED WITH AIR AT A TEMPERATURE ABOVE ABOUT 450*F. UNDER SUFFICIENT PRESCARBON DIOXIDE OR THE OXYGENATED ORGANIC COMPOUNDS OR BOTH ARE INTRODUCED AT SELECTED POINTS IN THE WASTE WATER STREAM TO STIMULATE THE GROWTH OF MICROORGANISMS WHICH CONSUME SOLUBLE NITROGEN AND PHOSPHORUS COMPOUNDS, WHICH MICOORGANISMS ARE THEN SENT ON TO THE COKING ZONE FOR COKING. BY THUS STIMULATING BIOLOGICAL PROCESSES WHICH CONSUME NITROGEN AND PHOSPHORUS COMPOUNDS THERE IS PRODUCED AN EFFLUENT WHICH CAN BE DISCHARGED INTO BODIES OF WATER WITHOUT CAUSING EUTROPHICATION OF THE WATERS.

Review of sludge disposal practices

Abstract: AMERICA an abundance at first of was pure blessed air, pure with an abundance of pure air, pure water, and vast virginal land areas. Rapid technological advances in industry, coupled with explosive population growths, have resulted in misuse and mismanagement of these resources to the point where pollution has become a serious problem. Although no accurate estimates are currently available of the magnitude of water treatment plant wastes, H. E. Hudson 1 reported at a recent University of Illinois Waste Disposal Conference that the volume of sludge produced annually from all water treatment plants in the United States is about 1,000,000 tons. This quantity of water treatment plant wastes amounts to 10 per cent of the total waste solids discharged to our waterways from municipal wastewater treatment. Discharge of water treatment plant wastes without treatment into small streams can cause problems, but its disposal into large bodies of water results in infinite dilution and loss of identity. For example, the Washington Aqueduct (WA) produces about 16,000 tons of alum sludge annually from about 68 bil gal of Potomac River water. Because the annual silt load of the Potomac is estimated to be 2,500,000 tons, the WA discharge is only 0.6 of 1 per cent of the entire river silt load. This small fraction of

Water purification apparatus

Abstract: Contaminated raw or waste water is delivered into at least one basin which is supported within a water-filled reservoir The contaminated water in said basin is subjected to mechanical, biological and/or chemical purification, and the treated effluent is caused to overflow into the reservoir The basin has a conical wall of supple nonporous material that yields readily to even slight movements of the water both internally and externally of the basin unit

Waste water disposal from a highly diversified fat and fatty acid plant

Abstract: A case history of waste water disposal at the Drew Chemical, Boonton, New Jersey plant is presented together with details of various treatments that have been studied. These include biological, chemical and physical treatment methods. Treatment of concentrated wastes having a soluble biochemical oxygen demand of approximately 10,000 mg/liter is emphasized.

Factors affecting pH change in alkaline waste water treatment - I

Abstract: The pH of wastewater in various stages of its purification depends mainly upon the equilibria of carbonic acid. Thus relations between pH and the concentrations of carbon dioxide, bicarbonate and carbonate can be formulated. Corrections for the non-ideal character of the sewage are necessary. With some restrictions the concept of alkalinity can be used for these pH relations. Several (bio)chemical and physical processes occurring in biological purification affect the concentrations of carbon dioxide and (bi)carbonate. Processes studied are carbon dioxide desorption, oxidation of organic matter and nitrification. Models are proposed for the calculation of the effluent pH and the values so obtained are compared with the available experimental results.

Phosphate Removal: Summary of Papers

Abstract: Summaries of 16 papers are presented with references to the authors of the original papers which were presented at a Federal Water Pollution Control Administration Conference on Phosphorus Removal from Wastewater at Chicago in June, 1968. These summaries are of processes comprising chemical precipitation, employing lime or alum and various means for solids separation; activated sludge removal; reverse osmosis; metallic salts and polyelectrolytes; activated Bentonite compound; and activated algae. This paper has been prepared as an activity of the Committee on Sewerage and Sewage Treatment for presenting summaries and abstracts of significant information on waste treatment, inclusive of subjects of research and demonstration projects.