Search results for "GREENHOUSE GAS"
showing 10 items of 259 documents
Greenhouse gases from wastewater treatment — A review of modelling tools
2016
Nitrous oxide, carbon dioxide and methane are greenhouse gases (GHG) emitted from wastewater treatment that contribute to its carbon footprint. As a result of the increasing awareness of GHG emissions from wastewater treatment plants (WWTPs), new modelling, design, and operational tools have been developed to address and reduce GHG emissions at the plant-wide scale and beyond. This paper reviews the state-of-the-art and the recently developed tools used to understand and manage GHG emissions from WWTPs, and discusses open problems and research gaps. The literature review reveals that knowledge on the processes related to N2O formation, especially due to autotrophic biomass, is still incompl…
Understanding water energy nexus in drinking water provision: an eco-efficiency assessment of water companies
2022
Producción Científica
Eco-Efficiency of the English and Welsh Water Companies: A Cross Performance Assessment
2021
Analyzing costs and greenhouse gas (GHG) emissions could be of great importance for the water utilities to supply water services in a healthy and sustainable manner. In this study, we measured the eco-efficiency of several water utilities in England and Wales by incorporating GHG as an undesirable output. For the first time, we evaluated the eco-efficiency of the water production process using robust cross-efficiency data envelopment analysis (DEA) techniques. The further use of clustering and regression techniques allowed us to better understand the drivers of eco-efficiency. The results showed that the mean eco-efficiency of the water sector was 0.748, which indicates that costs and GHG e…
High emissions of greenhouse gases from grasslands on peat and other organic soils
2016
Drainage has turned peatlands from a carbon sink into one of the world's largest greenhouse gas (GHG) sources from cultivated soils. We analyzed a unique data set (12 peatlands, 48 sites and 122 annual budgets) of mainly unpublished GHG emissions from grasslands on bog and fen peat as well as other soils rich in soil organic carbon (SOC) in Germany. Emissions and environmental variables were measured with identical methods. Site-averaged GHG budgets were surprisingly variable (29.2 ± 17.4 t CO2 -eq. ha-1 yr-1 ) and partially higher than all published data and the IPCC default emission factors for GHG inventories. Generally, CO2 (27.7 ± 17.3 t CO2 ha-1 yr-1 ) dominated the GHG budget. Nit…
Economic feasibility study for intensive and extensive wastewater treatment considering greenhouse gases emissions
2013
Economic feasibility assessments represent a key issue for selecting which wastewater treatment processes should be implemented. The few applications that exist focus on the positive economic value of externalities, overlooking the existence of negative externalities. However, wastewater treatment plants (WWTPs) consume a significant amount of energy, contributing to climate change. In this context, as a pioneering approach, greenhouse gas emissions (GHG) have been incorporated as a negative externality of wastewater treatment. Within this framework, this study aims to compare the economic feasibility of five technologies, both intensive and extensive, for small communities. The results sho…
Green Chemistry in Higher Education: State of the Art, Challenges, and Future Trends
2018
Nowadays, there is increasing interest in global sustainability, and thus, university students would like to know how human actions affect the health status of our planet. This is mainly due to their basic knowledge of problems such as global warming and greenhouse gases. Students would like to gain knowledge on how to safeguard the earth for future generations. This must involve changes in education programs at interested institutions and universities. To ensure that future generations of chemists are equipped with proper knowledge, significant efforts are needed. Thus, this article aims to present the history of green chemistry, its milestones, and ideas on how to teach this subject. A di…
Predicting in situ soil N2O emission using NOE algorithm and soil database
2005
This paper presents a new algorithm, Nitrous Oxide Emission (NOE) for simulating the emission of the greenhouse gas N2O from agricultural soils. N2O fluxes are calculated as the result of production through denitrification and nitrification and reduction through the last step of denitrification. Actual denitrification and nitrification rates are calculated from biological parameters and soil water-filled pore space, temperature and mineral nitrogen contents. New suggestions in NOE consisted in introducing (1) biological site-specific parameters of soil N2O reduction and (2) reduction of the N2O produced through nitrification to N2 through denitrification. This paper includes a database of 6…
Evaluating the Eco-Efficiency of Wastewater Treatment Plants: Comparison of Optimistic and Pessimistic Approaches
2020
The assessment of wastewater treatment plant (WWTP) performance has gained the interest of water utilities and water regulators. Eco-efficiency has been identified as a powerful indicator, as it integrates economic and environmental variables into a single index. Most previous studies have employed traditional data envelopment analysis (DEA) for the evaluation of WWTP eco-efficiency. However, DEA allows the selection of input and output weights for individual WWTPs for the calculation of eco-efficiency scores. To overcome this limitation, we employed the double-frontier and common set of weights methods to evaluate the eco-efficiency of a sample of 30 WWTPs in Spain. The WWTPs were ranked b…
Productivity growth of wastewater treatment plants – accounting for environmental impacts: a Malmquist-Luenberger index approach
2015
As the number of wastewater treatment plants (WWTPs) has increased, the economic considerations associated with their management have become more relevant. Measuring the productivity of WWTPs allows the best practice to be identified and resource use to be optimized. Previous studies assessing the productivity change of WWTPs have ignored undesirable outputs; thus, wastewater treatment was considered to be free of environmental impacts. To overcome this limitation and for the first time, we assessed the productivity growth of a sample of Spanish WWTPs, while also accounting for the emission of greenhouse gases and sludge production. The Malmquist-Luenberger productivity index (MLPI) and its…
The Unintended Side Effects of Bioplastics: Carbon, Land, and Water Footprints
2020
(One Earth 3, 45–53, July 24, 2020) In the originally published version of this article, the authors inadvertently used global volumes of bioplastics in plastic packaging instead of European volumes for Figure 1C. After noticing this, the authors recalculated European bioplastic packaging consumption, and as such, Figure 1 and its legend have been corrected in the online article (as shown below) to reflect all data sources used for estimating European bioplastic volumes in Figure 1C. In the Experimental Procedures, the Data and Code Availability section has been updated, and the section “Estimation of European Bioplastic Volumes” has been added. Additionally, reference 69 is new, and two in…