Towards a Reduction of Greenhouse Gases: a New Decision Support System for Design, Management and Operation of Wastewater Treatment Plants

The increasing attention for the environment has led to reduce the emissions from wastewater treatment plants (WWTPs). Moreover, the increasing interest towards the greenhouse gas (GHG) emissions from WWTPs suggests to reconsider the traditional tools used for designing and managing WWTPs. Indeed, nitrous oxide (N2O), carbon dioxide (CO2) and methane (CH4) can be emitted from wastewater treatment significantly contributing to the greenhouse gas (GHG) footprint. The reduction of energy consumption as well as GHG emission are of particular concern for large WWTPs which treat the majority of wastewater in terms of both volume and pollution load. Nowadays, there is an increasing need to develop new tools that include additional performance indicators related to GHG emissions and energy consumption as well as traditional effluent quality parameters. Energy consumption, in fact, can be considered as an indirect source of GHGs. This paper presents the development of a research project aiming at setting-up an innovative mathematical model platform for the design and management of WWTPs. The final goal of the project by means of this platform is to minimize the environmental impact of WWTPs through their optimization in terms of energy consumptions and emissions, which can be regarded as discharged pollutants, sludge and GHGs

Towards A New Decision Support System for Design, Management and Operation of Wastewater Treatment Plants for the Reduction of Greenhouse Gases Emission

The increasing attention paid to the environment has led to a reduction in the emissions from wastewater treatment plants (WWTPs). Moreover, the increasing interest in the greenhouse gas (GHG) emissions from WWTPs suggests that we reconsider the traditional tools used for designing and managing WWTPs. Indeed, nitrous oxide, carbon dioxide and methane can be emitted from wastewater treatment, significantly contributing to the greenhouse gas (GHG) footprint. The reduction of energy consumption as well as GHG emission are of particular concern for large WWTPs which treat the majority of wastewater in terms of both volume and pollution load. Nowadays, there is an increasing need to develop new tools that include additional performance indicators related to GHG emissions and energy consumption as well as traditional effluent quality parameters. Energy consumption, in fact, can be considered as an indirect source of GHGs. This paper presents the development of an ongoing research project aiming at setting-up an innovative mathematical model platform for the design and management of WWTPs. The final goal of the project by means of this platform is to minimize the environmental impact of WWTPs through their optimization in terms of energy consumptions and emissions, which can be regarded as discharged pollutants, sludge and GHGs

Towards a new protocol for field measurements of greenhouse gases from wastewater treatment plant

Emissions into the atmosphere of greenhouse gases (GHGs), i.e., carbon dioxide, methane and nitrous oxide from wastewater treatment plants are of increasing concern in the water industry. In order to produce useful and comparable information for monitoring, assessing and reporting GHG emissions from wastewater treatment plants, there is a crescent need for a general accepted methodology. This paper aims at proposing the first protocol for monitoring and accounting GHG emissions from wastewater treatment plants taking into account both direct and internal indirect emissions focusing on sections known to be major responsible of GHG emissions i.e. oxidation tanks and sludge digestion. The main novelties of the proposed protocol are: (i) direct and indirect internal emissions ascribed to aeration devices which are related each other, (ii) the monitoring of biogas composition in case of anaerobic digestion which affects GHG emissions offset due to biogas valorization systems and (iii) monitoring of non-aerated tanks

Towards a reduction of greenhouse gas emission from wastewater treatment plants: a new plant wide experimental and modelling approach

The increasing interest in greenhouse gas (GHG) emissions from wastewater treatment plants (WWTPs) has led to the development of new tools for their design and management. Studies about gas emissions show that the sewer collection and the wastewater treatment plant are anthropogenic GHG potential sources, so they contribute to the climate change and air pollution. A wastewater treatment plant receives wastewater from sewers and, while produces treated water for discharge into surface water, emits the three major greenhouse gases, CO2, CH4, and N2O, during the treatment processes, and additional amounts of CO2 and CH4 from the energy demands (Bani Shahabadi et al., 2009). Indeed, energy consumption can be considered as an indirect source of GHGs. Greenhouse-gas emissions are generated by water-line and sludge- line processes and by the on-site combustion of biogas and fossil fuels for energy generation. GHGs may also be produced during sludge disposal or reuse (transportation and degradation of remaining biosolids off-site), off-site energy production and off-site chemicals production. In recent years, increasing attention is given to the assessment of N2O emissions from WWTPs. N2O is a powerful greenhouse gas that is almost 300 times stronger than CO2. Nevertheless, the source and magnitude of N2O are relatively unknown and the knowledge is still incomplete. This paper presents the first results of an ongoing research project aiming at setting-up an innovative mathematical model platform (Decision Support System—DSS) for the design and management of WWTPs. The project is constituted by four research units (UOs) and its final goal is to minimize, by means of this platform, the environmental impact of WWTPs through their optimization in terms of energy consumptions and pollutants, sludge and GHG emissions

Dewatering of excess sludge produced by cas and mbr aerobic treatment plants. effects of biochemical stability and eps composition

This paper investigates the behavior of different sludges from several treatment plants at full and pilot scale configured as Conventional Activated Sludge (CAS) and Membrane Bio Reactor (MBR) plants treating different kinds of wastewaters. The sludges collected were subjected to complete analytical and technological characterization in order to correlate the rheological properties that affect the dewatering behavior to the sludge chemical physical properties. In detail the EPS from the samples collected is extracted and characterized in terms of carbohydrates, proteins, uronic acids and humic acids content. Moreover, once characterized, the sludges were subjected to AD in order to assess their bio-methanation potential and hence their biological stability. The final aim was to find correlations between the WWTP operational parameters (i.e. HRT, SRT, volumetric load coefficient, aeration) that finally affect its chemical composition (i.e. BMP, EPS composition) and the physical behavior of the sludge

Assessing the economic suitability of aeration and the influence of bed heating on constructed wetlands treatment efficiency and life-span

Intensive constructed wetlands including forced aeration and heating were studied to improve treatment efficiency and prevent clogging. The experiments were carried out in a pilot plant (0.4 m2) treating urban wastewater with an organic loading rate of 40-60 gCOD/m2∙d. Continuous and intermittent aeration was performed on 8% of the wetland surface, leading to different dissolved oxygen concentrations within the wetlands (from 0.2 to 5 mgO2/L). Continuous forced aeration increased organic matter (COD) and ammonium nitrogen removal by 56% and 69%, respectively. Improvements in 33 wastewater treatment caused by forced aeration can result into reduction of the surface area. This work demonstrated that for the studied configuration the cost of the power consumption of the continuous aeration was largely covered by the reduction of the wetlands surface. Even if the heating of 8% of the wetland surface at 21°C had no effects on treatment performances, positive results showed that solids accumulation rate within the granular medium, which is closely related to the development of clogging. It has been demonstrated that heating for 10 days per year during 20 year period would delay the equivalent of 1 year of solids accumulation

Towards A New Decision Support System for Design, Management and Operation of Wastewater Treatment Plants for the Reduction of Greenhouse Gases Emission

The increasing attention paid to the environment has led to a reduction in the emissions from wastewater treatment plants (WWTPs). Moreover, the increasing interest in the greenhouse gas (GHG) emissions from WWTPs suggests that we reconsider the traditional tools used for designing and managing WWTPs. Indeed, nitrous oxide, carbon dioxide and methane can be emitted from wastewater treatment, significantly contributing to the greenhouse gas (GHG) footprint. The reduction of energy consumption as well as GHG emission are of particular concern for large WWTPs which treat the majority of wastewater in terms of both volume and pollution load. Nowadays, there is an increasing need to develop new tools that include additional performance indicators related to GHG emissions and energy consumption as well as traditional effluent quality parameters. Energy consumption, in fact, can be considered as an indirect source of GHGs. This paper presents the development of an ongoing research project aiming at setting-up an innovative mathematical model platform for the design and management of WWTPs. The final goal of the project by means of this platform is to minimize the environmental impact of WWTPs through their optimization in terms of energy consumptions and emissions, which can be regarded as discharged pollutants, sludge and GHGs

Fuzzy Logic and Neuro-Fuzzy Networks for Environmental Hazard Assessment

Pollution and management of the environment are serious problems which concern the entire planet; the main responsibility should be attributed to human activities that contribute significantly to damage the environment, leading to an imbalance of natural ecosystems. In recent years, numerous studies focused on the three environmental compartments: soil, water and air. The pollution of groundwater is a widespread problem. The causes of pollution are often linked to human activities, including waste disposal. Solid waste management has become an important environmental issue in industrialized countries. The most serious problems are related to solid waste disposal. Landfill is still the most used disposal technique but not the safest. In fact, even controlled landfills could easily incur in the breakdown of containment elements. This breakdown could cause contamination of aquifer that is environmental pollution. Such contamination can be mitigated by performing remediation and environmental restoration. The assessment of environmental pollution risk can be performed with different degrees of detail and precision. Various statistical and mathematical models can be used for a qualitative risk assessment. The planning of a program for environmental remediation and restoration can be supported by expeditious methodologies that allow to obtain a hierarchical classification of contaminated sites. The literature offers some expeditious and qualitative methods including fuzzy logic (Zadeh, 1965), neural networks and neuro-fuzzy networks, which are more objective methods. The three artificial intelligence systems differ among themselves in some respects: fuzzy inference system learns knowledge of data only through the fuzzy rules; neural network is able to learn knowledge of data using the weights of synaptic connections; neuro-fuzzy systems are able to learn knowledge of neural data with neural paradigm and represent it in the form of fuzzy rules. Fuzzy logic was founded in 1965 by Zadeh. The first applications date back to the nineties. They were mainly used to control industrial processes, household electrical appliances and means of transport. Later, this approach was used in several fields including the environment. In fact it could be used for assessing environmental risk related to contamination of groundwater. The fuzzy approach is advantageous because it allows a quick assessment of the risk, but is disadvantageous because of the increasing complexity in the definition of fuzzy rules along with the increasing of the number of parameters. In many situations, when the number of parameters are considered high in the analysis, application of these techniques is cumbersome and complex and could be used for neuro-fuzzy models. These models reduce the complexity because they use training data. The neuro-fuzzy model were supported by a sensitivity analysis in order to address the problem of subjectivity and uncertainty of model input data

Use of carbon materials for produced water treatment: a review on adsorption process and performance

The oil and gas production is identified by consuming a large amount of water and generating massive produced water. The produced water is either reinjected into the underground layers or released into the rivers and oceans that can cause severe damage to the environment due to toxic elements such as salts, oil and grease, and polyaromatic hydrocarbons. So produced water treatment and management can reduce the significant threats to the soil and water resources and solve the lack of water in different water-consuming sectors. During the last decades, adsorption methods, such as using expanded graphite and activated carbon materials, have attracted scientists’ attention because these adsorbents are cost-effective and practical. This study aimed to review expanded graphite’s synthesis, adsorption process, and efficient factors in removing heavy oil, heavy metals, benzene, toluene, ethylbenzene, and xylenes, and organic acids from produced water and compare with other adsorbents, including activated carbon and residual biomass. Based on the results of extensive research works, expanded graphite’s high adsorption feature suggested that graphite can be a promising adsorbent in actual produced water treatment

The integrated action framework of Rete Natura 2000 Basilicata

Basilicata Natura 2000 network consists of 50 Sites of Community Importance (SCI) and 17 Special Protection Zones (SPZs), covering alltogether more than 17% of the regional area. This network, partially overlapping other forms of land protection, represents a valuable environmental, agricultural and cultural heritage, in which the safeguard of natural resources and landscapes has to be coupled with the needs of the local population; especially in relation to development and social welfare. The Natura 2000 project involved a panel of experts belonging to 15 different institutions, to form a steering committee with the following professional and scientific skills: vegetation, landscape, fauna, geology, agriculture, forestry, sea, architecture and planning, territorial analysis and representation. Along the 4 years project, the steering committee designed and coordinated the activities of over 150 professionals, mostly from Basilicata, who carried out field surveys and data analysis aimed at assessing the environmental conditions in the SCI and SPZs, proposing measures and plans, implementing thematic databases. SCI/SPZ management plans, by themselves, may not be sufficient to fulfill the requirements of an effective environmental policy, which has to go along with the awareness of people, citizens and local administrators about the instances of a sustainable policy. For this reason, the activities of surveying and management have been coupled with a communication project that involves all the experts and a relevant part of professionals who participated to the Natura 2000 project. The communication activity implies the use and the creation of several tools (publishing, video, websites, meetings, photo contests, social networks ...) targeted to different groups: policy makers (local, regional, national, European ), organizations, citizens, schools, farmers, small and medium enterprises (www.natura2000basilicata.it). A further goal is to feature the environmental highlights of Basilicata which are linked to a specific and often surprising integration of an ancient human presence with the natural elements, and the role performed by the traditional farming activities in the maintenance of ecosystem dynamics and services (in particular with agriculture). In fact, a good number of Natura 2000 sites can be considered High Nature Value Farmlands (HNVF, sensu E. Andersen, 2003), in which a virtuous relationship was established a long time ago between traditional practices and the environment itself. In this context, it combines the convergence between the activities carried on the Natura 2000 network and the project Agrival (http://utagri.enea.it/projects/agrival), a research project led by ENEA in Val d'Agri, in order to experimentally contribute to the methodology for the identification of the High Nature Value Farmlands and make them cohabit with the other economic activities in the local context. The process started with the project Basilicata Natura 2000 Network is therefore an interesting methodological model that, in coherence with the financial planning of the European Community for the period 2014-2020 (Brussels, 12.12.2011, COMM. 874) puts together projects on environmental issues to boost the meeting of agricultural, environmental, cultural and productive policies, fostered by the EC, and enhancing the implementation of the "Prioritized Actions Frameworks" (PAF), pointed out by the European Commission as the optimal tools for the management of Natura 2000 networks