DOCSLIB.ORG

Sludge Incineration: Good Practice and Environmental Aspects C M

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Sludge Incineration: Good Practice and Environmental Aspects C M Sludge incineration: good practice and environmental aspects C M. Braguglia*, G. Mininni*, D. Marani* and V. Lotito** *Cnr - Istituto di Ricerca sulle Acque - Via Reno, 1 - 00198 Roma * Cnr - Istituto di Ricerca sulle Acque - via F. De Blasio 5 - 70123 Bari (E-mail: mininnifcbirsa. rm.cnr.it) Abstract. Growing difficulties in the sludge utilization in agriculture or landfill make incineration an attractive alternative for sludge disposal. Capital and operating costs and concern about gaseous emissions may however limit convenience and acceptance. In this paper a model is presented for optimisation of the cake concentration before the furnace, allowing an autogenous operation with a minimization of exhaust gas production. As far as emissions of heavy metals and organic micropollutants at the stack is concerned, results of tests on a demonstrative plant, including a fluidised bed and a rotary kiln furnace, are presented. The tests were carried out in different feeding (sludge alone or spiked with chlorinated hydrocarbons) and operating conditions (temperature of the afterburning chamber). Key words Energy recovery; heavy metals; incineration; PAH; PCDD/F; thermal drying. Introduction Sewage sludge after mechanical dewatering still contains high moisture content (60-80 %) with a relevant low heat value of 6,000-3,000 kJ/kg. Sludge incineration is therefore quite expensive due to high auxiliary fuel consumption. Consequently, optimisation of energy recovery is of predominant importance to minimize capital and operating costs of a sludge incineration plant and to render attractive such option. Typical design approach for energy recovery in sludge incineration performed by fluidised bed furnace considers the useof a sludge drying system, usually performed by an indirect dryer utilizing steam produced in the heat recovery section. Design of dryer, furnace, and boiler strictly depends on solids concentration before and after drying and on the temperature of exhaust gases after boiler. Energy conversion and recovery in a sewage sludge incineration process are discussed enlightening dryer integration in the process. In addition to fuel consumption, the key factor determining feasibility and acceptability of sludge incineration plants is the potential emission of pollutants at the stack, with emphasis on metals and organic micropollutants. In this framework the results of a research activity on sludge combustion carried out by the Water Research Institute of the Italian National Research Council, are presented. Tests were carried out on a demonstrative plant equipped with a fluidised bed furnace (FBF) and a rotary kiln furnace (RKF) with the aim to investigate factors affecting emissions at the stack. Sludge drying and combustion modelling Basic assumptions for mass and enthalpic balances of a drying/incineration process by fluidised bed furnace are reported in Table 1. Enthalpy balances were developed considering specific heat data reported by Perry & Green (1984). An algorithm was developed to calculate cake concentration for autogenous combustion. Methane consumption (Nm3 /kg wet sludge) decreases proportionally vs. feed cake concentration to the furnace. The minimum cake concentration for autogenous combustion is 45.9 %. Incineration of a more concentrated cake requires additional fresh air to keep furnace temperature at 850 °C with consequent increasing production of exhaust gas. Composition of exhaust gases from the furnace is reported in Figure 1. Increasing cake concentration up to the point of autogenous combustion, humidity shows a linear decrease from 28.2 to 24.6 %, while oxygen remains constant at 6 %. After this point the decrease of humidity is exponential due to air dilution, whereas oxygen increases to a maximum value of 12.1 % at a 90 % cake concentration. 523 Table 1. Assumptions for enthalpic and mass balances in sludge drying and incineration (Task Force on Thermal Destruction, 1992) Parameter Values Elemental analysis of loss on ignition of dry solids C 53 %, H 7.7%, O 32.7 %, N 5.6 %, S 1 % Outlet temperature from the dryer 100 °C Extraction of non condensable gas from the dryer 1.5 kg/kg evaporated moisture Gross heat value of volatile solids (VS) 22,486 kJ/kg Gross heat value of methane 38,083 kJ/Nnf Heat losses (% of inlet and/or developed) 5 % in the furnace and the boiler; 7 % in the dryer Loss on ignition with respect to dry solids 70% Excessof air for methane combustion 20% Excessof air for VS combustion What needed to attain at least 6 % of oxygen in the gas Exhaust gas temperature 850°C Conversion of nitrogen in VS to NO 10% — C02 —H20 — N2 —02 Sludge solids concentration (weight fraction) Figure 1. Composition of exhaust gas from fluidised bed furnace As far as thermal drying is concerned, the theoretical model was developed considering the use of an indirect dryer with a recycle of dried product to agglomerate sludge, thus increasing specific exposure surface and avoiding clogging. Normally, it is necessary to feed the dryer with sludge at a solid concentration higher than 60 %. It is also useful to by-pass part of feed cake and mix it with the dried product to reach the pre-set cake concentration before incineration. The scheme of the dryer is shown in Figure2. The theoretical model of the incineration furnace implies the following sequential calculations: 1) minimum critical concentration (xu)cr allowing to operate the furnace in autogenous conditions; 2) maximum quantity of heat which can be recovered in the boiler downstream the furnace when the furnace is fed at the (xu)cr concentration, considering that gases exit the boiler at 250 °C; 3) feed concentration (xo)cr to the dryer producing a dried cake at (xu)CT recovering the heat calculated at point 2); 4) if x0<(xo)cr it is possible to determine the function xu=f(x0) by imposing the balance of the recoverable heat in the boiler with that needed in the dryer; 5) if xo>(x0)cr it is possible to determine the excess heat which is produced in the boiler not needed for drying which is available for electric energy production with an overall efficiency of 31.8 %; 6) the sequential procedure can be repeated with xu-0.9 (feeding the cake to the furnace at the highest practicable concentration). 524 Vapours and incondensable Re cycle stream 0,9-0.6 By - pass stream k _ (0.9; Xu) 1 Figure 2. Scheme of an indirect dryer with internal recycle and by-pass Figure 3 shows the function xu=fi(xo): when the cake concentration is lower than 21.1 % heat produced in the boiler is not sufficient to dry the sludge at the concentration needed for autogenous combustion. With cake concentration higher than 21.1 % excess heat is available if dried sludge is produced at 45.9 % or otherwise it is possible to obtain dried sludge at higher concentration. 0,9 -* 0.8 - Dried sludge limit concentration 0.5 - for autogenous combustion=45.9 % 1 0.25 Cake concentration to the dryer (weight fraction) Figure 3. Dried sludge concentration vs. cake concentration Electric energy production from surplus steam for a plant serving one million of inhabitants was evaluated for two levels of sludge drying (45.9 and 90 %). The amount of electric energy obtained in the former case is 0.362 - 0.378 MW higher than in case of drying at 90 %. This can be explained considering that the enthalpy of the extra production of steam (about 1,830 kJ/kg dry solids) with a 90 % cake does not balance the heat required for sludge drying from 45.9 to 90 % (3,180-3,260 kJ/kg dry solids). Environmental aspects of sludge incineration Incineration leads to a great reduction of sludge and theoretically should result in the total conversion of the hazardous organic compounds to inorganic end products. Unfortunately, burning conditions are not ideal and generally they cause inefficiencies, mainly due to non-uniform temperature and mixing conditions inside the furnace. Cooling of hot gases in the combustion zone 525 due to the contact with the cool walls or locally reducing conditions can induce partial destruction and pyrolysis reactions. These inefficiencies lead to the formation of toxic organic compounds, referred to as products of incomplete combustion. Among them, special attention is devoted to PAHs for their relative abundance in the emissions and potential impact on human health (Akimoto et al., 1997, Ana et at, 1999, Eiceman et aL, 1979, Mascolo et al, 1999). Some authors showed that they are the starting compounds for soot formation, which is suspected to be the active site for solid - gas reactions leading to PCDD/F formation (lino et al., 1999 a and b, Schoonenboom and Olie, 1995, Stieglietz et al. 1991). On the contrary, others observed that the conditions favouring PAH production generally suppress PCDD/F formation (Benestad et al., 1990, Oehme et al. 1987). Metals regulated in incineration systems include Ag, As, Ba, Be, Cd, Co, Cr, Cu, Hg, Pb, Mn, Ni, Sb, Se, Sn, Tl, V and Zn (The European Parliament and the Council of the European Union, 1994, van der Vlies and te Marvelde, 1992, Italian Ministry of the Environment, 1998, Linak, 1997). Among these metals, zinc typically presents the highest concentrations in sewage sludge. Lead, copper, chromium, manganese, nickel, cadmium, and arsenic may also be found in significant concentrations in sewage sludge, whereas mercury is typically present only at low concentrations. Some research has specifically addressed the fate of metals in sewage sludge incineration (Dewling et al., 1980, Gerstle and Albrinck, 1982, Parrish et al., 1991, Balogh, 1996). These works have shown that several metals are enriched in fly ash with respect to their concentration in the bottom ash, suggesting that volatile metal species are formed in the combustion furnace and carried away in the flue gas. Combustion temperature, excess air, feed composition (chlorine, sulfur, and water content) are the parameters that may affect metal speciation in the combustion chamber and consequently metal partitioning among the incineration residues (Fournier et al.
Load more

Recommended publications
  • Use of a Water Treatment Sludge in a Sewage Sludge Dewatering Process
    E3S Web of Conferences 30, 02006 (2018) https://doi.org/10.1051/e3sconf/20183002006 Water, Wastewater and Energy in Smart Cities Use of a water treatment sludge in a sewage sludge dewatering process Justyna Górka1,*, Małgorzata Cimochowicz-Rybicka1 , and Małgorzata Kryłów1 1 University of Technology, Department of Environmental Engineering, 24 Warszawska, Cracow 31- 155, Poland Abstract. The objective of the research study was to determine whether a sewage sludge conditioning had any impact on sludge dewaterability. As a conditioning agent a water treatment sludge was used, which was mixed with a sewage sludge before a digestion process. The capillary suction time (CST) and the specific filtration resistance (SRF) were the measures used to determine the effects of a water sludge addition on a dewatering process. Based on the CST curves the water sludge dose of 0.3 g total volatile solids (TVS) per 1.0 g TVS of a sewage sludge was selected. Once the water treatment sludge dose was accepted, disintegration of the water treatment sludge was performed and its dewaterability was determined. The studies have shown that sludge dewaterability was much better after its conditioning with a water sludge as well as after disintegration and conditioning, if comparing to sludge with no conditioning. Nevertheless, these findings are of preliminary nature and future studies will be needed to investigate this topic. 1 Introduction Dewatering of sludge is a very important stage of the sludge processing. It reduces both sludge mass and volume, which consequently reduces costs of a further sludge processing, facilitates its transport and allows for its thermal processing.
    [Show full text]
  • A Novel Waste Water Treatment Plant for the Disposal of Organic Waste from Mobile Toilets
    A Novel Waste Water Treatment Plant for The Disposal of Organic Waste from Mobile Toilets A Novel Waste Water Treatment Plant for The Disposal of Organic Waste from Mobile Toilets G. BONIFAZI, R. GASBARRONE, R. PALMIERI, G. CAPOBIANCO, S. SERRANTI Departments of Medical Sciences and Biotechnologies and of Chemical Eng. Materials, Environment- Sapienza University of Rome, Abstract The EU wastewater management industry is continuously looking for innovative technological solutions that can enter the market with a reduced environmental impact. This paper focuses on the problems associated to the disposal of human waste and on the specific market of the so-called mobile toilets. These are independent portable units equipped with sanitary tools that use chemical agents to disinfect the vessel and not connected to the sewer network. With growing awareness towards effective sanitation, mobile toilets have gained immense popularity in recent years and are now widely used at construction sites, event venues, public places, and in several other application like temporary refugee housing, migrants’ camps, military missions, cases of natural disasters, airplanes, trains, campers, caravans and campsites. This paper illustrates a new process for the disposal of organic waste from mobile toilets. Keywords: Waste Water Treatment Plants, Chemical Portable Toilets, Use of sludges in agriculture. 1. Introduction into surface and ground water and to avoid toxic effects on soil, plants, animals and humans. In The use of sludge in agriculture within the EU is most cases, national authorities have currently regulated only by the limits of heavy implemented policies supporting the use of metals (Cd, Cu, Hg, Ni, Pb and Zn) listed in sludge in agriculture, as it is considered to be the Council Directive 86/278/EEC.
    [Show full text]
  • Safe Use of Wastewater in Agriculture: Good Practice Examples
    SAFE USE OF WASTEWATER IN AGRICULTURE: GOOD PRACTICE EXAMPLES Hiroshan Hettiarachchi Reza Ardakanian, Editors SAFE USE OF WASTEWATER IN AGRICULTURE: GOOD PRACTICE EXAMPLES Hiroshan Hettiarachchi Reza Ardakanian, Editors PREFACE Population growth, rapid urbanisation, more water intense consumption patterns and climate change are intensifying the pressure on freshwater resources. The increasing scarcity of water, combined with other factors such as energy and fertilizers, is driving millions of farmers and other entrepreneurs to make use of wastewater. Wastewater reuse is an excellent example that naturally explains the importance of integrated management of water, soil and waste, which we define as the Nexus While the information in this book are generally believed to be true and accurate at the approach. The process begins in the waste sector, but the selection of date of publication, the editors and the publisher cannot accept any legal responsibility for the correct management model can make it relevant and important to any errors or omissions that may be made. The publisher makes no warranty, expressed or the water and soil as well. Over 20 million hectares of land are currently implied, with respect to the material contained herein. known to be irrigated with wastewater. This is interesting, but the The opinions expressed in this book are those of the Case Authors. Their inclusion in this alarming fact is that a greater percentage of this practice is not based book does not imply endorsement by the United Nations University. on any scientific criterion that ensures the “safe use” of wastewater. In order to address the technical, institutional, and policy challenges of safe water reuse, developing countries and countries in transition need clear institutional arrangements and more skilled human resources, United Nations University Institute for Integrated with a sound understanding of the opportunities and potential risks of Management of Material Fluxes and of Resources wastewater use.
    [Show full text]
  • Five Facts About Incineration Five Facts About Incineration
    Five facts about incineration Five facts about incineration Across the globe, cities are looking for ways to improve their municipal solid waste systems. In the search for services that are affordable, green and easy to implement, many cities are encouraged to turn to waste-to-energy (WtE) technologies, such as incineration.1 But, as found in WIEGO’s Technical Brief 11 (Waste Incineration and Informal Livelihoods: A Technical Guide on Waste-to-Energy Initiatives by Jeroen IJgosse), incineration is far from the perfect solution and, particularly in the Global South, can be less cost-effective, more complicated and can negatively impact the environment and informal waste workers’ livelihoods. Below, we have collected the top five issues highlighted in the study that show why this technology is a risky choice: 1. Incineration costs more than recycling. How incineration may be promoted: Incineration is a good economic decision because it reduces the costs associated with landfill operations while also creating energy that can be used by the community. The reality: • In 2016, the World Energy Council reported that, “energy generation from waste is a costly option, in comparison with other established power generation sources.” • Setting up an incineration project requires steep investment costs from the municipality. • For incineration projects to remain financially stable long-term, high fees are required, which place a burden on municipal finances and lead to sharp increases in user fees. • If incinerators are not able to collect enough burnable waste, they will burn other fuels (gas) instead. Contract obligations can force a municipality to make up the difference if an incinerator doesn’t burn enough to create the needed amount of energy.
    [Show full text]
  • 2.2 Sewage Sludge Incineration
    2.2 Sewage Sludge Incineration There are approximately 170 sewage sludge incineration (SSI) plants in operation in the United States. Three main types of incinerators are used: multiple hearth, fluidized bed, and electric infrared. Some sludge is co-fired with municipal solid waste in combustors based on refuse combustion technology (see Section 2.1). Refuse co-fired with sludge in combustors based on sludge incinerating technology is limited to multiple hearth incinerators only. Over 80 percent of the identified operating sludge incinerators are of the multiple hearth design. About 15 percent are fluidized bed combustors and 3 percent are electric. The remaining combustors co-fire refuse with sludge. Most sludge incinerators are located in the Eastern United States, though there are a significant number on the West Coast. New York has the largest number of facilities with 33. Pennsylvania and Michigan have the next-largest numbers of facilities with 21 and 19 sites, respectively. Sewage sludge incinerator emissions are currently regulated under 40 CFR Part 60, Subpart O and 40 CFR Part 61, Subparts C and E. Subpart O in Part 60 establishes a New Source Performance Standard for particulate matter. Subparts C and E of Part 61--National Emission Standards for Hazardous Air Pollutants (NESHAP)--establish emission limits for beryllium and mercury, respectively. In 1989, technical standards for the use and disposal of sewage sludge were proposed as 40 CFR Part 503, under authority of Section 405 of the Clean Water Act. Subpart G of this proposed Part 503 proposes to establish national emission limits for arsenic, beryllium, cadmium, chromium, lead, mercury, nickel, and total hydrocarbons from sewage sludge incinerators.
    [Show full text]
  • Energy Recovery from Sewage Sludge: the Case Study of Croatia
    energies Article Energy Recovery from Sewage Sludge: The Case Study of Croatia Dinko Đurđevi´c 1,* , Paolo Blecich 2 and Željko Juri´c 1 1 Energy Institute Hrvoje Požar, 10000 Zagreb, Croatia; [email protected] 2 Faculty of Engineering, University of Rijeka, 51000 Rijeka, Croatia; [email protected] * Correspondence: [email protected] Received: 26 April 2019; Accepted: 16 May 2019; Published: 20 May 2019 Abstract: Croatia produced 21,366 tonnes of dry matter (DM) sewage sludge (SS) in 2016, a quantity expected to surpass 100,000 tonnes DM by 2024. Annual production rates for future wastewater treatment plants (WWTP) in Croatia are estimated at 5.8–7.3 Nm3/people equivalent (PE) for biogas and 20–25 kgDM/PE of sewage sludge. Biogas can be converted into 12–16 kWhel/PE of electricity and 19–24 kWhth/PE of heat, which is sufficient for 30–40% of electrical and 80–100% of thermal autonomy. The WWTP autonomy can be increased using energy recovery from sewage sludge incineration by 60% for electricity and 100% of thermal energy (10–13 kWhel/PE and 30–38 kWhth/PE). However, energy for sewage sludge drying exceeds energy recovery, unless solar drying is performed. 2 The annual solar drying potential is estimated between 450–750 kgDM/m of solar drying surface. The lower heating value of dried sewage sludge is 2–3 kWh/kgDM and this energy can be used for assisting sludge drying or for energy generation and supply to WWTPs. Sewage sludge can be considered a renewable energy source and its incineration generates substantially lower greenhouse gases emissions than energy generation from fossil fuels.
    [Show full text]
  • Mobility of Heavy Metals in Municipal Sewage Sludge from Different Throughput Sewage Treatment Plants
    Pol. J. Environ. Stud. Vol. 21, No. 6 (2012), 1603-1611 Original Research Mobility of Heavy Metals in Municipal Sewage Sludge from Different Throughput Sewage Treatment Plants Jarosław Gawdzik1*, Barbara Gawdzik2** 1Faculty of Civil and Environmental Engineering, Kielce University of Technology, Division of Waste Management, Al. 1000-lecia Państwa Polskiego 7, 25-314 Kielce, Poland 2Institute of Chemistry, Faculty of Mathematics and Science, Jan Kochanowski University of Humanities and Sciences, Świętokrzyska 15, 25-406 Kielce, Poland Received: 27 June 2011 Accepted: 11 May 2012 Abstract Sewage sludge heavy metals can be dissolved, precipitated, co-precipitated with metal oxides, and adsorbed or associated on the particles in biological debris. Heavy metals are found in the form of oxides, hydroxides, sulphides, sulphates, phosphates, silicates, organic bindings forming complexes with humic com- pounds, and complex sugars. Polish regulations specifying the maximum levels of heavy metals in municipal sewage sludge used for agricultural purposes refer to the total content of lead, cadmium, mercury, nickel, zinc, copper, and chromium. The aim of our study was to evaluate the mobility of heavy metals in sewage sludge from wastewater treatment plants in Świętokrzyskie Province. Stabilized sewage sludge from wastewater treatment was ana- lyzed in accordance with the extraction method proposed by the Community Bureau of Reference (BCR). Zinc, cadmium, lead, and nickel were determined by means of the standard addition with the use of a Perkin-Elmer 3100-BG FAAS atomic absorption spectrophotometer. Chromium and copper were tested using the FAAS technique. The sequence analysis revealed the presence of heavy metals in all fractions (F-I, F-II, F-III, F-IV).
    [Show full text]
  • Safe Use of Wastewater in Agriculture Safe Use of Safe Wastewater in Agriculture Proceedings No
    A UN-Water project with the following members and partners: UNU-INWEH Proceedings of the UN-Water project on the Safe Use of Wastewater in Agriculture Safe Use of Wastewater in Agriculture Wastewater Safe of Use Proceedings No. 11 No. Proceedings | UNW-DPC Publication SeriesUNW-DPC Coordinated by the UN-Water Decade Programme on Capacity Development (UNW-DPC) Editors: Jens Liebe, Reza Ardakanian Editors: Jens Liebe, Reza Ardakanian (UNW-DPC) Compiling Assistant: Henrik Bours (UNW-DPC) Graphic Design: Katja Cloud (UNW-DPC) Copy Editor: Lis Mullin Bernhardt (UNW-DPC) Cover Photo: Untited Nations University/UNW-DPC UN-Water Decade Programme on Capacity Development (UNW-DPC) United Nations University UN Campus Platz der Vereinten Nationen 1 53113 Bonn Germany Tel +49-228-815-0652 Fax +49-228-815-0655 www.unwater.unu.edu [email protected] All rights reserved. Publication does not imply endorsement. This publication was printed and bound in Germany on FSC certified paper. Proceedings Series No. 11 Published by UNW-DPC, Bonn, Germany August 2013 © UNW-DPC, 2013 Disclaimer The views expressed in this publication are not necessarily those of the agencies cooperating in this project. The designations employed and the presentation of material throughout this publication do not imply the expression of any opinion whatsoever on the part of the UN, UNW-DPC or UNU concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. Unless otherwise indicated, the ideas and opinions expressed by the authors do not necessarily represent the views of their employers.
    [Show full text]
  • The Global E-Waste Monitor 2020 Quantities, Flows, and the Circular Economy Potential
    The Global E-waste Monitor 2020 Quantities, flows, and the circular economy potential Authors: Vanessa Forti, Cornelis Peter Baldé, Ruediger Kuehr, Garam Bel Contributions by: S. Adrian, M. Brune Drisse, Y. Cheng, L. Devia, O. Deubzer, F. Goldizen, J. Gorman, S. Herat, S. Honda, G. Iattoni, W. Jingwei, L. Jinhui, D.S. Khetriwal, J. Linnell, F. Magalini, I.C. Nnororm, P. Onianwa, D. Ott, A. Ramola, U. Silva, R. Stillhart, D. Tillekeratne, V. Van Straalen, M. Wagner, T. Yamamoto, X. Zeng Supporting Contributors: 2 The Global E-waste Monitor 2020 Quantities, flows, and the circular economy potential Authors: Vanessa Forti, Cornelis Peter Baldé, Ruediger Kuehr, Garam Bel Contributions by: S. Adrian, M. Brune Drisse, Y. Cheng, L. Devia, O. Deubzer, F. Goldizen, J. Gorman, S. Herat, S. Honda, G. Iattoni, W. Jingwei, L. Jinhui, D.S. Khetriwal, J. Linnell, F. Magalini, I.C. Nnororm, P. Onianwa, D. Ott, A. Ramola, U. Silva, R. Stillhart, D. Tillekeratne, V. Van Straalen, M. Wagner, T. Yamamoto, X. Zeng 3 Copyright and publication information 4 Contact information: Established in 1865, ITU is the intergovernmental body responsible for coordinating the For enquiries, please contact the corresponding author C.P. Baldé via [email protected]. shared global use of the radio spectrum, promoting international cooperation in assigning satellite orbits, improving communication infrastructure in the developing world, and Please cite this publication as: establishing the worldwide standards that foster seamless interconnection of a vast range of Forti V., Baldé C.P., Kuehr R., Bel G. The Global E-waste Monitor 2020: Quantities, communications systems. From broadband networks to cutting-edge wireless technologies, flows and the circular economy potential.
    [Show full text]
  • Circular Economy in Wastewater Treatment Plant– Challenges and Barriers †
    Proceedings Circular Economy in Wastewater Treatment Plant– Challenges and Barriers † Ewa Neczaj * and Anna Grosser Faculty of Infrastructure and Environment, Czestochowa University of Technology, 42-201 Czestochowa, Poland; [email protected] * Correspondence: [email protected]; Tel.: +48-343-250-917 † Presented at the 3rd EWaS International Conference on “Insights on the Water-Energy-Food Nexus”, Lefkada Island, Greece, 27–30 June 2018. Published: 31 July 2018 Abstract: The urban wastewater treatment plants can be an important part of circular sustainability due to integration of energy production and resource recovery during clean water production. Currently the main drivers for developing wastewater industry are global nutrient needs and water and energy recovery from wastewater. The article presents current trends in wastewater treatment plants development based on Circular Economy assumptions, challenges and barriers which prevent the implementation of the CE and Smart Cities concept with WWTPs as an important player. WWTPs in the near future are to become “ecologically sustainable” technological systems and a very important nexus in SMART cities. Keywords: circular economy; wastewater treatment plant; resource recovery 1. Introduction The circular economy (CE) is the concept in which products, materials (and raw materials) should remain in the economy for as long as possible, and waste should be treated as secondary raw materials that can be recycled to process and re-use [1]. This distinguishes it from a linear economy based on the, ‘take-make-use-dispose’ system, in which waste is usually the last stage of the product life cycle. CE is a concept promotes sustainable management of materials and energy by minimalizing the amount of waste generation and their reuse as a secondary material.
    [Show full text]
  • Waste Management
    10 Waste Management Coordinating Lead Authors: Jean Bogner (USA) Lead Authors: Mohammed Abdelrafie Ahmed (Sudan), Cristobal Diaz (Cuba), Andre Faaij (The Netherlands), Qingxian Gao (China), Seiji Hashimoto (Japan), Katarina Mareckova (Slovakia), Riitta Pipatti (Finland), Tianzhu Zhang (China) Contributing Authors: Luis Diaz (USA), Peter Kjeldsen (Denmark), Suvi Monni (Finland) Review Editors: Robert Gregory (UK), R.T.M. Sutamihardja (Indonesia) This chapter should be cited as: Bogner, J., M. Abdelrafie Ahmed, C. Diaz, A. Faaij, Q. Gao, S. Hashimoto, K. Mareckova, R. Pipatti, T. Zhang, Waste Management, In Climate Change 2007: Mitigation. Contribution of Working Group III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [B. Metz, O.R. Davidson, P.R. Bosch, R. Dave, L.A. Meyer (eds)], Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. Waste Management Chapter 10 Table of Contents Executive Summary ................................................. 587 10.5 Policies and measures: waste management and climate ....................................................... 607 10.1 Introduction .................................................... 588 10.5.1 Reducing landfill CH4 emissions .......................607 10.2 Status of the waste management sector ..... 591 10.5.2 Incineration and other thermal processes for waste-to-energy ...............................................608 10.2.1 Waste generation ............................................591 10.5.3 Waste minimization, re-use and
    [Show full text]
  • Chapter 9 Agricultural Waste Management Systems
    Part 651 Agricultural Waste Management Field Handbook Chapter 9 Agricultural Waste Management Systems (210–VI–AWMFH, Amend. 47, December 2011) Chapter 9 Agricultural Waste Management Systems Part 651 Agricultural Waste Management Field Handbook Issued December 2011 The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or a part of an individual’s income is derived from any public assistance program. (Not all prohibited bases apply to all pro- grams.) Persons with disabilities who require alternative means for commu- nication of program information (Braille, large print, audiotape, etc.) should contact USDA’s TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, SW., Washington, DC 20250–9410, or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer. (210–VI–AWMFH, Amend. 47, December 2011) Acknowledgments Chapter 9 was originally prepared and printed in 1992 under the direction of James N. Krider (retired), national environmental engineer, Soil Conser- vation Service (SCS), now Natural Resources Conservation Service (NRCS). James D. Rickman (retired), environmental engineer, NRCS, Fort Worth, Texas, provided day-to-day coordination in the development of the hand- book. Authors for chapter 9 included L.M. “Mac” Safley, North Carolina State University, Raleigh, NC; William H. Boyd, environmental engineer, Lincoln, Nebraska; A.
    [Show full text]