Series of anionic flocculants with outstanding flocculation performance, poly(acrylic acid-co-acrylamide)/diatomite composite flocculants (PAAD) were successfully prepared through aqueous solution copolymerization and applied to flocculate from oil-field fracturing waste-water. The structure of PAAD was characterized by Fourier transform infra-red spectroscopy , 13C nuclear magnetic resonance and X-ray diffraction tests, and its properties were systematically evaluated by viscometer, thermogravimetry analysis and flocculation measurements. Furthermore, the influences of various reaction parameters on the apparent viscosity of flocculant solution were studied, and the optimum synthesis condition was determined. The novel composite flocculants exhibited outstanding flocculation properties. Specifically, the dosage of composite flocculants that could make the transmittance of treated wastewater exceed 90% was only approximately 12–35 ppm, which was far lower than that of conventional flocculants. Meanwhile, the settling time was lower than 5 s, which was similar to that of conventional flocculants. This was because PAAD flocculants had a higher absorption capacity, and larger chain extending space than conventional linear flocculants, which could refrain from the entanglement of linear polymer chains and significantly improve flocculation capacity.
Mechanically degraded food fluids were modelled as Power law fluids in a pilot scale (42 l) helical ribbon agitation vessel. Effective rheological representative flow curves determined from speed/torque data proved comparable to off-line laboratory rheometer measured data. Modelling effective viscosity as a Power law function gave effective consistency coefficient Keff which correlated strongly with K from the rheometer (R2<SUP2< sup>=0.99). Effective flow behaviour index neff was comparable in magnitude...
Chem-bioflocculation (CBF) process was a new municipal wastewater treatment process developed in recent years. The flocculant dosage was one of the most important factors in operation optimization of chem-bioflocculation(CBF) treatment process. Five levels of flocculant dosage (PAFC) from 30mg/L to 100mg/L were applied to compare operational performance between CBF process and chemically enhanced primary treatment (CEPT) process. Superior column loadings of COD, SCOD, SS, and NH4+-N were obtained in CBF process....
Abstract
Improving our ability to predict the impact of climate change on the carbon (C) balance of boreal forests requires increased understanding of site-specific factors controlling detrital and soil C accumulation. Jack pine (Pinus banksiana) and black spruce (Picea mariana) stands along the Boreal Forest Transect Case Study (BFTCS) in northern Canada have similar C stocks in aboveground vegetation and large woody detritus, but thick forest floors of poorly-drained black spruce stands have much higher C...
Abstract The coalescence characteristics of oil droplets which are attached on flocs after coagulation is different from coalescence of droplets which are suspended in emulsions. The droplets attached on flocs are stationary and do not collide as those in emulsions. Objectives of this study were to investigate the change in size distribution of oil droplets that were attached on flocs after coagulation. The surface water–oil emulsion was prepared by mixing water, clay and ethyl benzene. Flocculation/coagulation...
The occurrence of Synedra spp. in the source water of the CheongJu water treatment plant (South Korea) decreased filter run times of rapid sand filters to below 5 hours. During the filter-clogging episode, full-scale Synedra removal by coagulation with polyaluminium hydrogen chloride silicate (PAHCS), flocculation and sedimentation ranged from 20 to 70%. To reduce filter clogging, strategies needed to be developed to improve the coagulation of Synedra. Jar test results showed that alum was more effective for...
The paper discusses conversion capacities of both anaerobic and aerobic wastewater treatment systems in relation to growth kinetics, hydrodynamics and biomass concentration. In the current modern anaerobic high-rate reactors the conversion potentials are optimally exploited. This is not yet true for aerobic systems since operation of aerobic systems under conditions of low biomass growth reduces the maximum applicable loading rates significantly. Both the concept of granulation and the introduction of fluidised...
Abstract
A waste treatment unit has been designed to recover water and various components from an aluminum can manufacturing process. Due to the scarcity of water in the Middle East and its inherent cost, water recovery is both necessary and cost effective. The manufacturing process generates: 1) an 11,356 L/hr (50 gpm) aqueous stream contaminated with hydrofluoric acid, dissolved aluminum, and various oil/surfactant complexes at a pH of <2 and 2) a 2,271 L/hr (10 gpm) aqueous stream with 3-10% emulsified...
ABSTRACT
This paper proposes the application of Open-Path Fourier Transform Infra-Red (OP-FTIR) spectroscopy to measure aerosols. A preliminary experiment conducted in a standard shower chamber generated a condensed water aerosol cloud. The OP-FTIR beam acquired spectra through the cloud of water droplets. We matched calculated extinction spectra to measured extinction in the spectral range between 500 and 5000 wavenumbers by using Mie theory for spherical particles. The results indicate that size distribution...
Abstract
The paper presents the results obtained for zinc recovery from residual solution resulting from dimetridazol (1,2 dimethyl 5-nitro glyoxaline) fabrication (a drug for animal use) and its reuse in the process. The authors propose a flow-sheet for zinc recovery with efficiency higher than 99% like a complex compound which can be reintroduced in the process with good results. The mother liquor resulted after zinc separation contains 28-30% sodium nitrate and can be used in the treatment of wheat, potatoes...
Introduction
The leak repair requirements, under Title VI Section 608 of the Clean Air Act Amendments of 1990, require that when an owner or operator of an appliance that normally contains a refrigerant charge of more than 50 pounds discovers that refrigerant is leaking at a rate that would exceed the applicable trigger rate during a 12-month period, the owner or operator must take corrective action. The Clean Air Act also requires that refrigerant vented into the atmosphere during installation, service or...
The minimization of wastes requiring disposal is increasingly important as available disposal options become more and more constrained, and particularly as more substances enter everyday use which are not readily decomposed in the natural environment and which can present long term hazards. This note sets out some basic principles for waste minimization in industrial processes, where `minimization` is taken to include avoidance of the generation of wastes where practical and the productive utilization of any...
` Management of hazardous waste is a growing concern in many countries. The long-term impacts and costs of improper disposal can be very high and the emphasis must be on prevention. A comprehensive management system should include (i) policies, institutions and effective regulations and (ii) adequate and acceptable disposal facilities (either public or private). This note outlines the key elements of such a system.`
Problems
Improper disposal of hazardous waste is an increasing problem in many developing...
Throughout American history, technological and institutional innovation has increased our prosperity. Public leadership has encouraged businesses, workers, and consumers to invest in new ideas that meet the challenges of one generation, paving the path to a better world for the next generation. The energy system that fuels our 20th century economy exemplifies such progress through partnership. Most of this system is built upon innovations of the 19th century, when coal was industrialized and oil commercialized,...
It may be necessary to know other subsurface information to remediate inorganics in ground water, surface water, and leachate. Treatability studies are usually necessary to ensure that the contaminated ground water can be treated effectively at the design flow. A subsurface geologic characterization would be particularly important to characterize the effects of adsorption and other processes of attenuation. Ground water models are also often needed to predict flow characteristics, changes in contaminant mixes and...
Customer comments
No comments were found for A novel poly(acrylic acid-co-acrylamide)/diatomite composite flocculant with outstanding flocculation performance. Be the first to comment!
