Nitrogen species (NH3-N, NO3-N, and NO2-N) are found as one of the major dissolved constituents in wastewater or stormwater runoff. In this research, laboratory experiments were conducted to remove these pollutants from the water environment using radiata pine (Pinus radiata) sawdust. A series of batch tests was conducted by varying initial concentration, dosage, particle size, pH, and contact time to check the removal performance. Test results confirmed the effectiveness of radiata pine sawdust for removing these contaminants from the aqueous phase (100% removal of NO3-N, and NO2-N; 55% removal of NH3-N). The adsorbent dosage and initial concentration showed a significantly greater effect on the removal process over pH or particle sizes. The optimum dosage for contaminant removal on a laboratory scale was found to be 12 g. Next, the adsorption kinetics were studied using intraparticle diffusion, liquid-film diffusion, and a pseudo-first order and pseudo-second order model. The adsorption of all species followed a pseudo-second order model but NO2-N adsorption followed both models. In addition, the kinetics of NO2-N adsorption showed two-step adsorption following intraparticle diffusion and liquid-film diffusion. The isotherm study showed that NO3-N and NO2-N adsorption fitted slightly better with the Freundlich model but that NH3-N adsorption followed both Freundlich and Langmuir models.
The use of biofilters to remove nitrogen and other pollutants from urban stormwater runoff has demonstrated varied success across laboratory and field studies. Design variables including plant species and use of a saturated zone have large impacts upon performance. A laboratory column study of 22 plant species and designs with varied outlet configuration was conducted across a 1.5-year period to further investigate the mechanisms and influences driving biofilter nitrogen processing. This paper presents outflow...
Untitled Document
When the Environmental
Protection Agency (EPA) threatened to put shipyards in the Coos Bay Estuary
on the National Priorities List of hazardous waste sites, the Charleston Marina
Complex, in Coos Bay, Ore., responded quickly. The EPA and Oregon Department
of Environmental Quality (DEQ) determined that the area surrounding the complex’s
Charleston Boatyard was contaminated with heavy metals, poly-aromatic hydrocarbons
and tributyl tin.
The agencies...
ABSTRACT
The A-01 effluent outfall, which collects both normal daily process flow and stormwater runoff from a industrial research facility, did not meet the South Carolina Department of Health and
Environmental Control (SCDHEC) National Pollutant Discharge Elimination System (NPDES) permit limits for metals, toxicity, and total residual chlorine at the outfall sampling point.
Copper was the constituent of primary concern and the effluent consistently failed to meet that NPDES limit. Installation of a construct...
Abstract
Africa
The economic and social needs of Africa depends more on its environmental resources but these natural resources are seriously declining and that is really effecting the entire region. Sustainable development in this rapidly changing region has become an imperative, and must take place in the complex context of a diverse and changing ecosystem, political transition and evolution toward market economies.
The region is heading towards integrating environmental components into sectors like...
Decontamination companies and researchers in France are working to restore polluted soil using treatments that range from biological methods to soil washing and incineration. The problem of polluted soil was dramatically illustrated prior to construction of the Stade de France soccer stadium built for the 1998 World Cup. The location of the site, on industrial wasteland just north of Paris, caused immense difficulties for the developers. Tens of thousands of cubic meters of earth contaminated by a gasworks had to...
Abstract
Restriction of available water observed in the last years in arid or semiarid areas forces the planners to consider any source of water for irrigation. The purpose of this paper was to investigate the suitability of wastewater produced by the treatment plant of the city of Larissa, Central Greece for irrigation of corn. With a three year`s field experiment it was shown that wastewater significantly increased corn yield and may substitute considerable quantities of mineral fertilizers. Increase in corn...
Traditional risk management posits a rational, five-step process for managing risks. The outstanding differences between this traditional process and the environmental risk management process lie in the technicality and complexity of step one (identifying and analyzing environmental risk) and of the first part of step two (examining the feasibility of alternative risk management, specifically risk control techniques). The two main differences between the environmental risk management process in the context of a...
Carlton United Brewery installed a Trade Waste Monitoring System to analyse the temperature, flows, pH and chemical compounds in their trade wastewater. This cleaner production initiative was a licensing condition of the Northern Territory`s Power and Water Authority (PAWA). As a result of the pretreatment, CUB is able to discharge their brewery wastewater to sewer.
Background
Carlton and United Breweries purchased the Darwin Brewery in October 1996 and commenced operations in November 1996. The Brewery is...
Introduction
Pollution Prevention Guidelines to provide technical advice and guidance to staff and consultants involved in pollution-related projects. The guidelines represent state-of-the-art thinking on how to reduce pollution emissions from the production process. In many cases, the guidelines provide numerical targets for reducing pollution, as well as maximum emissions levels that are normally achievable through a combination of cleaner production and end-of-pipe treatment. The guidelines are designed to...
Introduction
Pollution Prevention Guidelines to provide technical advice and guidance to staff and consultants involved in pollution-related projects. The guidelines represent state-of-the-art thinking on how to reduce pollution emissions from the production process. In many cases, the guidelines provide numerical targets for reducing pollution, as well as maximum emissions levels that are normally achievable through a combination of cleaner production and end-of-pipe treatment. The guidelines are designed to...
ABSTRACT
This technology status report provides a snapshot of the status of the in situ flushing remediation technology. The information provided herein is a reflection of the content of the Ground-Water Remediation Technologies Analysis Center’s (GWRTAC’s) case study database for innovative technologies. GWRTAC’s case study database is not represented as being comprehensive, nor are the case studies included screened to verify their validity, quality, or “success” in remediation. Rather the case study database...
In the semi-arid region surrounding Whyalla in South Australia, BHP is creating an artificial wetland that promises to make its effluent cleaner than its input water. The wetland is projected to cost around 40% of a conventional treatment works, with significantly less operating costs. The project will conserve one of the most precious resources in the world’s driest country - water - and will improve the local environment. The wetland`s design may also be picked up by local authorities to treat stormwater and...
Cavitation is a major problem in the chemical industry because it affects a basic tool, the centrifugal pump. A sudden increase in the velocity of the pumped liquid reduces the inlet pressure, sometimes below the vapor pressure.The result is formation of gas and bubbles.
Detecting the signs of cavitation, and correctly identifying and understanding the type of cavitation present, can help an operator prevent serious damage.
HOW CAVITATION OCCURS
The pressure of the liquid in a centrifugal pump drops as it...
The Northern Territory University’s Faculty of Science have designed and installed a ‘Neutralization Pit’ as their ‘cleaner production initiative. The primary objectives of the Northern Territory University adopting this form of treatment for the chemical wastewater generated by the Faculty of Science was to:
Prevent pollution and eutrophication of the receiving Darwin watercourses as untreated waste water particularly water containing chemical wastewater compounds can cause significant environmental and...
Introduction Sustainability or `sustainable development` has become a term which is frequently applied to land use and social planning and resource issues. Sustainability is a concept which draws attention to development practices which can degrade natural ecosystems and deplete natural resources. If development is defined broadly to include any cultural activity, then sustainable development may be defined as any practice that meets the needs of the present population without compromising the ability of future...
Ford Australia Ltd replaced an existing hot caustic paint stripping process, used for cleaning car skids, with a high pressure water jet system. This project has resulted in annual savings in the order of $300,000 from reduced chemical, energy and waste disposal costs. Significant improvements in paint quality were also achieved through the ability to clean the skids on a more regular basis than had been possible previously. This cleaner production success has given Ford the incentive to look for other opportunitie...
Introduction
Solidification/stabilization (S/S) reduces the mobility of hazardous substances and contaminants in the environment through both physical and chemical means. Unlike other remedial technologies, S/S seeks to trap or immobilize contaminants within their `host` medium (i.e., the soil, sand, and/or building materials that contain them), instead of removing them through chemical or physical treatment. Leachability testing is typically performed to measure the immobilization of contaminants. S/S techniques...
Electrokinetics separates and extracts contaminants from saturated or unsaturated soils, sludges and sediments, and groundwater. The goal of electrokinetic remediation is to effect the migration of subsurface contaminants in an imposed electric field via electroosmosis, electromigration and/or electrophoresis. These phenomena occur when the soil is electrically charged with a low voltage current. The fundamental configuration for all three processes involves the application of an electrical potential between...
Reuse/Recycle: Recovery and reuse technologies for energetic materials, including both explosives and propellants, should be considered at explosives waste sites for several reasons. First, new recovery methods and potential uses for reclaimed explosive materials are rapidly developing. Second, recovery/reuse options reduce overall remediation costs by eliminating destruction costs and allowing the value of reclaimed materials to be recovered. Finally, EPA`s treatment hierarchy, which is based on environmental...
The United States Pharmacopeial Convention Inc. (USP) has proposed new specifications for Water for Injection (WFI) and Purified Water (PW). These specifications will include quantitative conductivity, and total organic carbon (TOC) measurements will replace 100-year-old qualitative wet chemistry tests. The impetus behind these changes is to create a means of analysis that is less labor-intensive, yet more reflective of the water quality. A comparison of the current and proposed specifications is given in Table...
Customer comments
No comments were found for Adsorption kinetics and equilibrium study of nitrogen species onto radiata pine (Pinus radiata) sawdust. Be the first to comment!
