Implementation Of Treatment Technologies Research Articles

Accounting and Healthcare Waste Management: Strategies to Improve Financial Efficiency and Reduce Environmental Impact

Healthcare waste management represents both a financial and environmental challenge for healthcare institutions. This article discusses accounting and financial management strategies that can be implemented to optimize operational costs related to healthcare waste disposal, while minimizing environmental impact. A theoretical framework based on financial and environmental sustainability is proposed, integrating environmental accounting policies and waste management methodologies. The results demonstrate that adequate financial planning and the implementation of treatment technologies can significantly reduce costs and improve efficiency in healthcare waste management. The findings highlight the need for more robust management policies and greater investment in sustainable treatment technologies.

Pharmaceutical compounds in urban drinking waters of Ecuador

Introduction: Emerging contaminants (ECs) are substances with widely diverse chemical structures that may pose a risk to the environment and human beings. The limited scope of water treatment facilities, particularly in low and middle-income countries, allows ECs to be continuously introduced to the environment and become part of the cycle again for potabilization. In this work, we study for the first time the presence of these compounds in the drinking water of five Ecuadorian cities.Methods: The compounds of interest were mainly pharmaceutical substances commonly present in prescription and over-the-counter medicines, along with caffeine, a known coadjuvant in some of these preparations. Samples were collected from Quito, Guayaquil, Cuenca, Ibarra, and Esmeraldas, considering each city’s distribution systems, and, after solid-phase extraction, analyzed by LC-MS/MS ESI+.Results and discussion: Results showed a high occurrence of caffeine, the only analyte present in all cities, with concentrations ranging from <6.35 to 201 ngL-1 and an occurrence from 11% in Quito to 77% in Cuenca. The highest median was found in Cuenca, followed by Esmeraldas. Our observations regarding concentrations are comparable to other studies around the globe. Although in other cities, some pharmaceuticals appeared at levels below our detection limits. These findings highlight the ubiquitous nature of emerging contaminants while pointing out the need for regulatory frameworks that facilitate the implementation of treatment technologies at the source and wastewater level. These actions will safeguard public and environmental health in the long term.

Urban stormwater runoff pollutant loadings: GIS land use classification vs. sample-based predictions.

Cities are growing worldwide with an increase in stormwater quantity and decrease in quality, negatively impacting receiving water bodies. The characterization of stormwater is difficult given its high variability and the typically numerous outfalls to be monitored. However, loadings can be estimated via models and validated using actual outfall monitoring. This study determined stormwater pollutant loadings predicted using eight land-use classifications (i.e., a 'desktop' study) and via an outfall sampling regime (i.e., a 'monitoring' study) for seven stormwater catchment areas in Saskatoon, SK, Canada, where stormwater typically releases directly into the South Saskatchewan River. Pollutants considered were total suspended solids (TSS), chemical oxygen demand (COD), metals, and polycyclic aromatic hydrocarbons. Catchment areas were dominated by single-family residential (39%) and green areas (17%). The largest catchment area, Preston Crossing, was the major source of the predicted annual loadings, such as TSS at 550,000kg and COD at 265,000kg. For comparison, the sampled-based estimated loadings for TSS and COD were 362,700kg and 652,700kg, respectively. Differences between the average predicted and actual estimations ranged from 29 to 156% for the eight pollutants considered, with averages for the summed pollutants in each catchment area ranging from 48 to 130%. Overall, the assessment and monitoring of stormwater outfalls are needed for the determination of impacts of loadings on the environment and for the subsequent development and implementation of treatment technologies.

A robust framework to predict mercury speciation in combustion flue gases

Mercury emissions from coal combustion have become a global concern as growing energy demands have increased the consumption of coal. The effective implementation of treatment technologies requires knowledge of mercury speciation in the flue gas, namely concentrations of elemental, oxidized and particulate mercury at the exit of the boiler. A model that can accurately predict mercury species in flue gas would be very useful in that context. Here, a Bayesian regularized artificial neural network (BRANN) that uses five coal properties and combustion temperature was developed to predict mercury speciation in flue gases before treatment technology implementation. The results of the model show that up to 97 percent of the variation in mercury species concentration is captured through the use of BRANNs. The BRANN model was used to conduct a parametric sensitivity which revealed that the coal chlorine content and coal calorific value were the most sensitive parameters, followed by the combustion temperature. The coal sulfur content was the least important parameter. The results demonstrate the applicability of BRANNs for predicting mercury concentration and speciation in combustion flue gas and provide a more efficient and effective technique when compared to other advanced non-mechanistic modeling strategies.

TiO2-Photocatalyzed As(III) Oxidation in a Fixed-Bed, Flow-Through Reactor

Compliance with the U.S. drinking water standard for arsenic (As) of 10 microg L(-1) is required in January 2006. This will necessitate implementation of treatment technologies for As removal by thousands of water suppliers. Although a variety of such technologies is available, most require preoxidation of As(III) to As(V) for efficient performance. Previous batch studies with illuminated TiO2 slurries have demonstrated that TiO2-photocatalyzed AS(III) oxidation occurs rapidly. This study examined reaction efficiency in a flow-through, fixed-bed reactor that provides a better model for treatment in practice. Glass beads were coated with mixed P25/sol gel TiO2 and employed in an upflow reactor irradiated from above. The reactor residence time, influent As(III) concentration, number of TiO2 coatings on the beads, solution matrix, and light source were varied to characterize this reaction and determine its feasibility for water treatment. Repeated usage of the same beads in multiple experiments or extended use was found to affect effluent As(V) concentrations but not the steady-state effluent As(III) concentration, which suggests that As(III) oxidation at the TiO2 surface undergoes dynamic sorption equilibration. Catalyst poisoning was not observed either from As(V) or from competitively adsorbing anions, although the higher steady-state effluent As(III) concentrations in synthetic groundwater compared to 5 mM NaNO3 indicated that competitive sorbates in the matrix partially hinder the reaction. A reactive transport model with rate constants proportional to incident light at each bead layer fit the experimental data well despite simplifying assumptions. TiO2-photocatalyzed oxidation of As(III) was also effective under natural sunlight. Limitations to the efficiency of As(III) oxidation in the fixed-bed reactor were attributable to constraints of the reactor geometry, which could be overcome by improved design. The fixed-bed TiO2 reactor offers an environmentally benign method for As(III) oxidation.

Best management practices to prevent cross‐media transfers during soil cleanup

AbstractCleanup activities often focus on the initial and final concentration levels of contaminants. What happens in‐between, during implementation of treatment technologies, has raised major concerns by several environmental groups. To address this issue, the U.S. Environmental Protection Agency (EPA) has undertaken the task of developing a guidance that would identify the potential for cross‐media transfer during implementation of various soil treatment technologies and recommend best management practices (BMPs) to prevent or control these cross‐media transfers. The soil treatment technologies have been grouped into seven major categories in this effort. This article provides some details of the seven soil treatment technology groups and the general BMPs recommended in the draft BMP guidance document. One case history of existing control practices is also presented in this article and compared with the recommended BMPs.