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Tan C, He C, Fletcher J, Waite TD. Energy recovery in pilot scale membrane CDI treatment of brackish waters. WATER RESEARCH 2020; 168:115146. [PMID: 31627136 DOI: 10.1016/j.watres.2019.115146] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 09/15/2019] [Accepted: 09/30/2019] [Indexed: 06/10/2023]
Abstract
An energy recovery technique using a high-current bi-directional dc-dc converter for membrane capacitive de-ionization (mCDI) of brackish waters is described and it's performance assessed in a pilot-scale prototype. The energy recovery system is shown to reduce the energy consumption of the pilot-scale mCDI unit, powered by photovoltaics and with battery storage, by between 30 and 40%. Use of a stopped flow process also enables water recovery of up to 87%. The contributions to energy consumption in the system are quantified with the insights gained from this analysis enabling the selection of an optimum voltage range for desorption termination that maximizes the daily recovered energy. The experimental results demonstrate that energy usage by the mCDI process of lower than 0.4 kWh/m3 is achievable with almost 40% of the energy supplied by the batteries recovered.
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Iervolino G, Zammit I, Vaiano V, Rizzo L. Limitations and Prospects for Wastewater Treatment by UV and Visible-Light-Active Heterogeneous Photocatalysis: A Critical Review. Top Curr Chem (Cham) 2019; 378:7. [PMID: 31840195 DOI: 10.1007/978-3-030-49492-6_7] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 11/26/2019] [Indexed: 05/19/2023]
Abstract
Heterogeneous photocatalysis (HPC) has been widely investigated in recent decades for the removal of a number of contaminants from aqueous matrices, but its application in real wastewater treatment at full scale is still scarce. Indeed, process and technological limitations have made HPC uncompetitive with respect to consolidated processes/technologies so far. In this manuscript, these issues are critically discussed and reviewed with the aim of providing the reader with a realistic picture of the prospective application of HPC in wastewater treatment. Accordingly, consolidated and new photocatalysts (among which the visible active ones are attracting increasing interest among the scientific community), along with preparation methods, are reviewed to understand whether, with increased process efficiency, these methods can be realistically and competitively developed at industrial scale. Precipitation is considered as an attractive method for photocatalyst preparation at the industrial scale; sol-gel and ultrasound may be feasible only if no expensive metal precursor is used, while hydrothermal and solution combustion synthesis are expected to be difficult (expensive) to scale up. The application of HPC in urban and industrial wastewater treatment and possible energy recovery by hydrogen production are discussed in terms of current limitations and future prospects. Despite the fact that HPC has been studied for the removal of pollutants in aqueous matrices for two decades, its use in wastewater treatment is still at a "technological research" stage. In order to accelerate the adoption of HPC at full scale, it is advisable to focus on investigations under real conditions and on developing/improving pilot-scale reactors to better investigate scale-up conditions and the potential to successfully address specific challenges in wastewater treatment through HPC. In realistic terms, the prospective use of HPC is more likely as a tertiary treatment of wastewater, particularly if more stringent regulations come into force, than as pretreatment for industrial wastewater to improve biodegradability.
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He C, Zhang Z, Ge C, Liu W, Tang Y, Zhuang X, Qiu R. Synergistic effect of hydrothermal co-carbonization of sewage sludge with fruit and agricultural wastes on hydrochar fuel quality and combustion behavior. WASTE MANAGEMENT (NEW YORK, N.Y.) 2019; 100:171-181. [PMID: 31541922 DOI: 10.1016/j.wasman.2019.09.018] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 08/22/2019] [Accepted: 09/13/2019] [Indexed: 06/10/2023]
Abstract
In order to improve fuel quality of sewage sludge, fruit and agricultural wastes have been selected for hydrothermal co-carbonization. After hydrothermal co-carbonization, organics retention was facilitated, while O/C and H/C atomic ratios of hydrochars were substantially upgraded. Particularly, hydrochar from hydrothermal co-carbonization of sewage sludge with peanut shells at mass ratio of 1:3 (denoted as "SS:PS = 1:3") showed the highest fuel ratio of 0.79 and its carbon content was increased to 50.0% with significantly decreased O/C and H/C atomic ratios. Furthermore, higher heating value of hydrochars from hydrothermal co-carbonization was increased by nearly 2.65-fold and reached 21.72 MJ/kg. Moreover, the most favorable aromatization occurred when sewage sludge and peanut shells blending ratio was 3:1 or 1:1, whereas hydrothermal co-carbonization induced more CO and OH than COOH in hydrochars due to synergistic decarboxylation. A relatively higher value of point of zero charge for hydrochars from hydrothermal co-carbonization implied improved hydrophobicity. Combustion kinetics results indicated that hydrothermal co-carbonization balanced activation energies of hydrochars in devolatilization/combustion stage and char combustion process, rendering a more stable and lasting combustion profile. Hydrochars "SS:PS = 1:3" demonstrated desirable combustion performance. Therefore, hydrothermal co-carbonization can realize sustainable utilization of organic solid wastes towards superior hydrochar solid biofuels.
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Yang G, Wang J, Zhang H, Jia H, Zhang Y, Fang H, Gao F, Li J. Fluctuation of electrode potential based on molecular regulation induced diversity of electrogenesis behavior in multiple equilibrium microbial fuel cell. CHEMOSPHERE 2019; 237:124453. [PMID: 31394439 DOI: 10.1016/j.chemosphere.2019.124453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 06/17/2019] [Accepted: 07/24/2019] [Indexed: 06/10/2023]
Abstract
In this study, the electrogenesis behaviors and mechanisms in multiple equilibrium microbial fuel cells (MEMFCs) which volatile fatty acids as multiple electron donors are investigated. The electrochemical property and energy recovery can be enhanced in propionic acid dominant systems (HPr-D-MEMFCs) which compares to butyric acid dominant systems (HBu-D-MEMFCs), increase power density from 0.04 to 0.43 W/m2 and energy recovery efficiency from 2.07 to 5.44%, respectively. With isotope experiment analysis, the fluctuation of electrode potentials induce diverse electrogenesis pathways that high utilization efficiencies and bioconversion efficiency of hybrid acids observed in HPr-D-MEMFCs which different with HAc-D-MEMFCs and HBu-D-MEMFCs. In addition, the electrochemical and microbial community variation of MEMFCs reveal that the direct interspecies electron transfer stimulated with higher electric double layer capacitance, and activities of exoelectrogens enhanced with high relative abundance in HPr-D-MEMFCs. The findings present an intensive study in electrogenesis, providing a promising way to promote energy recovery and further extend its application value.
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Cheng F, Mallick K, Henkanatte Gedara SM, Jarvis JM, Schaub T, Jena U, Nirmalakhandan N, Brewer CE. Hydrothermal liquefaction of Galdieria sulphuraria grown on municipal wastewater. BIORESOURCE TECHNOLOGY 2019; 292:121884. [PMID: 31400652 DOI: 10.1016/j.biortech.2019.121884] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Revised: 07/21/2019] [Accepted: 07/22/2019] [Indexed: 06/10/2023]
Abstract
Two strains of Galdieria sulphuraria algae, 5587.1 and SOOS, were grown on municipal wastewater to develop energy-positive treatment systems. Hydrothermal liquefaction (HTL) of 5-10 wt% algal biomass solids was conducted at 310-350 °C for 5-60 min to produce bio-crude oil. HTL product yields and energy recovery were compared to those from previous studies using G. sulphuraria grown on a modified Cyanidium medium. Total bio-crude oil yields were lower (11.2-23.0 wt%) and char yields were higher (22.6-36.4 wt%) for HTL of algae grown on actual wastewater compared with that grown on media (31.4 wt% and 4.8 wt%, respectively), indicating a potential limitation for using yields from media-based studies. High-resolution mass spectroscopy of bio-crude oil provides new insights into differences in composition based on growth media. Energy recovery in total bio-crude oil and char at 350 °C was 17-28% and 14-19%, respectively, for the 5587.1 strain, and 23-27% and 14-25%, respectively, for the SOOS strain.
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Strazzabosco A, Kenway SJ, Lant PA. Solar PV adoption in wastewater treatment plants: A review of practice in California. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 248:109337. [PMID: 31386989 DOI: 10.1016/j.jenvman.2019.109337] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 07/29/2019] [Accepted: 07/29/2019] [Indexed: 06/10/2023]
Abstract
This is the first study to assess the current status of solar photovoltaic (PV) adoption across a range of wastewater treatment plant sizes, and to identify the opportunities for solar PV in the wastewater sector. It quantifies solar PV contributions to the energy demand of the wastewater treatment plants and improves knowledge of sector-specific factors influencing PV uptake. California was used as a case study due to its high commitment to solar power and the high data availability. The study compiled and examined data on multiple wastewater treatment plant attributes from 105 Californian plants, representing 78% of total state flows. The analysis focused on the effect of three sector-specific influencing factors: size of wastewater treatment plant, presence/absence of anaerobic digestion and geographical location (urban vs rural). Solar PV adoption was observed to vary significantly with the size of the wastewater treatment plants. Of the 105 plants analysed, 41 installed a solar PV system. Of these 41, 39 were installed in wastewater treatment plants with a flow rate below 50 mega gallons day-1 (MGD). Only two plants with flow above 50 MGD had solar PV installed. In wastewater treatment plants with a flow rate above 5 MGD, solar PV was primarily installed in hybrid configurations with anaerobic digestion. In these plants, biogas contributed 25-65% to the overall energy demand, while solar provided 8-30%. In wastewater treatment plants with a flow rates below 5 MGD, solar PV often represented the only source of renewable energy, producing 30-100% of the energy demand of these plants. Across all the plants analysed, 1 MW was the most adopted solar installation size and solar PV installations were mostly found in wastewater treatment plants in rural settings. While acknowledging multiple other factors of potential influence, these results demonstrate the role of solar PV in wastewater treatment plants under three sector-specific influencing factors. The results will support the sector in making informed decisions over solar PV investments, helping wastewater utilities to transition towards sustainable management practices.
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Mainardis M, Flaibani S, Trigatti M, Goi D. Techno-economic feasibility of anaerobic digestion of cheese whey in small Italian dairies and effect of ultrasound pre-treatment on methane yield. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 246:557-563. [PMID: 31202020 DOI: 10.1016/j.jenvman.2019.06.014] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 04/26/2019] [Accepted: 06/04/2019] [Indexed: 05/16/2023]
Abstract
In Friuli-Venezia Giulia plain (North-East of Italy), a significant number of small diaries is present; this study was aimed at evaluating technical and economic feasibility of diffused anaerobic digestion implementation at dairy level. Different kinds of cheese whey were characterized, and biochemical methane potential tests were executed. Good methane yields (up to 437.3 NmL CH4/g VSadded) were obtained, applying an inoculum-to-substrate ratio of 6. Ultrasound pre-treatment was investigated to evaluate an eventual increase in methane production and kinetics, varying applied ultrasonic energy: significant increases in methane yield (maximum +16.0%) and CH4 production kinetics (up to +46% increase after 3 days) were obtained at low ultrasonic energy of 251.4-693.7 Wh/kg VS, while at higher ultrasonic energy of 502.8-1387.5 Wh/kg VS no significant effect was visible. Energy consumption in selected dairies was analysed, to underline the impact of anaerobic digestion implementation on electric and thermal energy need, and it was concluded that through cheese whey anaerobic digestion it is possible to cover most of the dairies energy demand. Specific electric and thermal energy consumption were evaluated to be respectively in the range of 0.009-0.133 kWh/kg milk and 0.247-0.557 MJ/kg milk, while specific energy costs were calculated as 0.0079-0.0308 €/kg milk. For each analysed plant, digester volume to install and organic loading rate were hypothesized.
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Maaz M, Yasin M, Aslam M, Kumar G, Atabani AE, Idrees M, Anjum F, Jamil F, Ahmad R, Khan AL, Lesage G, Heran M, Kim J. Anaerobic membrane bioreactors for wastewater treatment: Novel configurations, fouling control and energy considerations. BIORESOURCE TECHNOLOGY 2019; 283:358-372. [PMID: 30928198 DOI: 10.1016/j.biortech.2019.03.061] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 03/11/2019] [Accepted: 03/11/2019] [Indexed: 06/09/2023]
Abstract
Water shortage, public health and environmental protection are key motives to treat wastewater. The widespread adoption of wastewater as a resource depends upon development of an energy-efficient technology. Anaerobic membrane bioreactor (AnMBR) technology has gained increasing popularity due to their ability to offset the disadvantages of conventional treatment technologies. However there are several hurdles, yet to climb over, for wider spread and scale-up of the technology. This paper reviews fundamental aspects of anaerobic digestion of wastewater, and identifies the challenges and opportunities to the further development of AnMBRs. Membrane fouling and its implications are discussed, and strategies to control membrane fouling are proposed. Novel AnMBR configurations are discussed as an integrated approach to overcome technology limitations. Energy demand and recovery in AnMBRs is analyzed. Finally key issues that require urgent attention to facilitate global penetration of AnMBR technology are highlighted.
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134
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Wu Y, Wang L, Jin M, Kong F, Qi H, Nan J. Reduced graphene oxide and biofilms as cathode catalysts to enhance energy and metal recovery in microbial fuel cell. BIORESOURCE TECHNOLOGY 2019; 283:129-137. [PMID: 30901585 DOI: 10.1016/j.biortech.2019.03.080] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 03/13/2019] [Accepted: 03/16/2019] [Indexed: 06/09/2023]
Abstract
In this study, reduced graphene oxide (rGO) was developed and employed as cathode catalyst in a membrane-less microbial fuel cell (MFC) to improve energy and metal (copper) recovery in combined with biofilms. Results showed that rGO-based cathode exhibited better characterizations in structure and electron transfer than graphene oxide (GO)-based cathode. The voltage with rGO was about 67% increased, and Cu2+ removal efficiency was 43% improved as compared to GO. Cu species on cathode demonstrated the favorable Cu2+ reduction to Cu with the catalysis of rGO. Moreover, microbial community analysis indicated that rGO-based cathode exhibited better biocompatibility for functional bacteria that related to electron transfer and Cu2+ resistance, such as Geobacter and Pseudomonas, demonstrating the interspecific synergism of microorganisms for efficient energy and copper recovery. It will be of important significance for the heavy metal and energy recovery from low concentrations wastewater by using microbial fuel cell.
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135
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Mayer F, Bhandari R, Gäth S. Critical review on life cycle assessment of conventional and innovative waste-to-energy technologies. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 672:708-721. [PMID: 30974361 DOI: 10.1016/j.scitotenv.2019.03.449] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 03/20/2019] [Accepted: 03/29/2019] [Indexed: 04/14/2023]
Abstract
In this study 315 peer-reviewed studies on environmental life cycle assessment (LCA) of waste-to-energy (WtE) technologies were critically analysed. The technologies considered were anaerobic digestion, hydrothermal carbonization, pyrolysis, gasification and incineration. It was found that overall increasingly more studies are concerned with LCA on waste-treatment systems. Although incineration and anaerobic digestion were primarily assessed, especially in recent years, a growing number of LCA-studies investigated advanced thermal treatment options. The geographical scope within the studies under review focused mainly on European (195 studies) and Asian (68 studies) regions. In regards to their quality, a majority of the analysed studies were marked by several shortcomings and showed poor compliance with the ISO 14040 and ISO 14044. 55 studies did not present a functional unit and >45% of all reviewed studies did not present a life cycle inventory. More than 50% of the reviewed studies omitted a sensitivity analysis and a comprehensive assessment of all impact categories was not present in most studies. By selecting studies that analysed two or more different WtE treatment options, the global warming potential and the acidification potential of the considered five different technologies were compared. By contrasting advanced treatment options against incineration, substantial environmental benefits of advanced treatment options could not be observed. However, only 34 studies fulfilled the criteria to be taken into account for this comparison. The main finding within this scope, was that anaerobic digestion and gasification seemed to outcompete incineration in the conversion process of waste. Cascaded waste treatment, i.e. combining several treatment technologies, was only present in few studies. Environmental benefits could be assigned to these treatment paths in most cases. Lastly, techno-economic aspects are highlighted and appropriate policies are deducted from the obtained results.
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136
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Zhang M, Gu J, Liu Y. Engineering feasibility, economic viability and environmental sustainability of energy recovery from nitrous oxide in biological wastewater treatment plant. BIORESOURCE TECHNOLOGY 2019; 282:514-519. [PMID: 30878291 DOI: 10.1016/j.biortech.2019.03.040] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Revised: 03/06/2019] [Accepted: 03/07/2019] [Indexed: 06/09/2023]
Abstract
Currently, the biological wastewater treatment has been challenged by their high energy consumption. An increasing effort has been devoted to exploring energy recovery from nitrous oxide (N2O) as a powerful fuel additive rather than as an unwanted byproduct during biological nitrogen removal. This review aims to offer a holistic and critical analysis of the ideas for N2O production and energy recovery in terms of engineering feasibility, economic viability and environmental sustainability. It turns out that the recoverable energy from N2O produced in municipal wastewater is below 0.03 kWh/m3, which is insignificant compared with the in-plant energy consumption, while complicated process configuration and high cost associated with harvesting and post-purification of N2O will be incurred. An environmental risk related to global climate change due to the emission of residual dissolved N2O is also concerned. Further effort on N2O production and recovery technologies is indeed required to improve the overall energy balance.
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137
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Ye Y, Ngo HH, Guo W, Chang SW, Nguyen DD, Liu Y, Nghiem LD, Zhang X, Wang J. Effect of organic loading rate on the recovery of nutrients and energy in a dual-chamber microbial fuel cell. BIORESOURCE TECHNOLOGY 2019; 281:367-373. [PMID: 30831516 DOI: 10.1016/j.biortech.2019.02.108] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Revised: 02/22/2019] [Accepted: 02/24/2019] [Indexed: 06/09/2023]
Abstract
This study aimed to assess the impacts of organic loading rate (OLR) (435-870 mgCOD/L·d) on nutrients recovery via a double-chamber microbial fuel cell (MFC) for treating domestic wastewater. Electricity generation was also explored at different OLRs, including power density and coulombic efficiency. Experimental results suggested the MFC could successfully treat municipal wastewater with over 90% of organics being removed at a wider range of OLR from 435 to 725 mgCOD/L·d. Besides, the maximum power density achieved in the MFC was 253.84 mW/m2 at the OLR of 435 mgCOD/L·d. Higher OLR may disrupt the recovery of PO43--P and NH4+-N via the MFC. The same pattern was observed for the coulombic efficiency of the MFC and its highest value was 25.01% at the OLR of 435 mgCOD/L·d. It can be concluded that nutrients and electrical power can be simultaneously recovered from municipal wastewater via the dual-chamber MFC.
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138
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Tang J, Zhang C, Shi X, Sun J, Cunningham JA. Municipal wastewater treatment plants coupled with electrochemical, biological and bio-electrochemical technologies: Opportunities and challenge toward energy self-sufficiency. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 234:396-403. [PMID: 30639863 DOI: 10.1016/j.jenvman.2018.12.097] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2018] [Revised: 12/22/2018] [Accepted: 12/26/2018] [Indexed: 06/09/2023]
Abstract
Municipal wastewater treatment plants (WWTPs) will face challenges in the coming decades including reducing energy consumption and decreasing carbon emissions. These challenges can be addressed by combining electrochemical, biological, and bio-electrochemical technologies within existing WWTPs. The results from this review indicate that electrochemical technology is an effective advanced treatment method for WWTPs. However, electrochemical technology is not yet economically suitable as a stand-alone unit for treating wastewater because it consumes energy in the operation process. Electricity generation from biological and bio-electrochemical technologies can provide the power supply needed for WWTP electrochemical processes while reducing greenhouse gas emissions. WWTPs coupled with electrochemical, biological, and bio-electrochemical technologies can increase electricity recovery in WWTPs, impart energy self-sufficiency to the WWTPs, and decrease greenhouse gas emissions.
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139
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Li R, Liu D, Zhang Y, Zhou J, Tsang YF, Liu Z, Duan N, Zhang Y. Improved methane production and energy recovery of post-hydrothermal liquefaction waste water via integration of zeolite adsorption and anaerobic digestion. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 651:61-69. [PMID: 30227293 DOI: 10.1016/j.scitotenv.2018.09.175] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Revised: 09/12/2018] [Accepted: 09/13/2018] [Indexed: 06/08/2023]
Abstract
Hydrothermal liquefaction (HTL) is a promising technology for converting organic wastes into bio-crude oil, with organic-rich post-hydrothermal liquefaction wastewater (PHWW) as by-product. In this study, zeolite adsorption and anaerobic digestion (AD) were integrated to improve the methane production and energy recovery of PHWW from Chlorella 1067. A statistical design for maximum toxicants removal by zeolite was applied before AD process. Zeolite could mitigate the inhibition associated to compounds such as ammonia, N-heterocyclic compounds, etc. in PHWW and thereby shortening the lag phase and increasing methane production by 32-117% compared with that without zeolite adsorption. Zeolite adsorption also increased energy recovery efficiency (up to 70.5%) for this integrated system. Integration of HTL and AD brought higher energetic return from feedstock via oil and biomethane production, which may offer insight into industrial application of microalgae biomass in the circular economy. In addition, carbon and nitrogen flow for the integrated process was determined.
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140
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Santos RED, Santos IFSD, Barros RM, Bernal AP, Tiago Filho GL, Silva FDGBD. Generating electrical energy through urban solid waste in Brazil: An economic and energy comparative analysis. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 231:198-206. [PMID: 30342332 DOI: 10.1016/j.jenvman.2018.10.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 09/11/2018] [Accepted: 10/06/2018] [Indexed: 06/08/2023]
Abstract
The search for alternative energy sources and increasing concerns over the generation of municipal solid waste are two widely discussed themes in contemporary academic literature. A possible alternative for solving both of these problems is through electrical energy generation through the use of this waste material. Although this practice is encouraged by the Brazilian National Solid Waste Policy, energy production through such methods still requires improvement. Given these considerations, this study aims to evaluate the generation of electric energy from solid waste in three different systems (biogas from sanitary landfills; methanization of organic fraction in anaerobic digesters; and combustion in incinerators) through economic and energy analysis. Economic analysis was performed with the parameters Net Present Value and Levelized Cost of Electricity. Economic viability was only seen in the cases which considered landfill biogas energy recovery, demonstrating a need for incentives and support policies to enable technologies that are environmentally more advantageous than landfills.
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141
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Marin-Batista JD, Villamil JA, Rodriguez JJ, Mohedano AF, de la Rubia MA. Valorization of microalgal biomass by hydrothermal carbonization and anaerobic digestion. BIORESOURCE TECHNOLOGY 2019; 274:395-402. [PMID: 30551042 DOI: 10.1016/j.biortech.2018.11.103] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 11/29/2018] [Accepted: 11/30/2018] [Indexed: 06/09/2023]
Abstract
The potential of hydrothermal carbonization (HTC) as a novel choice for treating microalgal biomass (MAB) was assessed. The hydrochar obtained at 210 °C had a carbon content and a higher heating value (HHV) 1.09 and 1.1 times greater, respectively, than that of the feedstock. Also, washing the hydrochar with HCl efficiently removed ash and increased its carbon content 1.40-fold. Energy recovery in the liquid fraction from the hydrothermal treatment (LF) by anaerobic digestion (AD) allowed methane yields of 188-356 mL STP CH4 g-1 VSadded, to be obtained. As a result, the amount of energy recovered from MAB was increased from about 4 MJ kg-1 (20% in terms of HHV) to 15.4, 12.1 and 10.4 MJ kg-1 by combining HTC at 180, 210 and 240 °C, respectively, with AD. Therefore, HTC at 180 °C in combination with AD seemingly provides an effective method for valorizing MAB.
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142
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Chen G, Wang X, Li J, Yan B, Wang Y, Wu X, Velichkova R, Cheng Z, Ma W. Environmental, energy, and economic analysis of integrated treatment of municipal solid waste and sewage sludge: A case study in China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 647:1433-1443. [PMID: 30180349 DOI: 10.1016/j.scitotenv.2018.08.104] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 08/05/2018] [Accepted: 08/07/2018] [Indexed: 06/08/2023]
Abstract
Incineration is well used to treat municipal solid wastes (MSW) but is difficult to treat sewage sludge (SS) because it requires a large amount of heat to remove high content of moisture in SS. Over 50 billion tons of SS are discharged annually in China, and the need for a better waste treatment strategy is urgent. This paper is to introduce a waste disposal technology referring to the integrated treatment of MSW and SS. Four scenarios were analyzed including Mono-incineration of MSW (Case 1) and SS (Case 2), co-incineration of SS and MSW by traditional (Case 3) and integrated ways (Case 4), in terms of environment, energy and economic impact by means of LCA, CED and TEA method. From the environmental perspective, the top four mid-point categories involving the largest effect on four cases are N-C (non-carcinogens), OLD (Ozone layer depletion), TET (Terrestrial eco-toxicity), and GWP (Global warming potential). Case 4 has the most positive effect on climate change and resources (-1.44 kg CO2 eq and -18 MJ, respectively) according to end-point categories. From the view of energy, Case 4 shows the best performance of energy efficiency, and significantly saves the non-renewable energy (0.21 t coal per ton feedstock compared with Case 3). From the economic part, Case 4 is preferentially potential with the best profit, cutting down 79.08% of cost in coal than that in Case 3. These results provide understandings of developing an effective approach for co-treating MSW and SS in the near future.
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143
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Ghosh P, Shah G, Chandra R, Sahota S, Kumar H, Vijay VK, Thakur IS. Assessment of methane emissions and energy recovery potential from the municipal solid waste landfills of Delhi, India. BIORESOURCE TECHNOLOGY 2019; 272:611-615. [PMID: 30385029 DOI: 10.1016/j.biortech.2018.10.069] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 10/23/2018] [Accepted: 10/25/2018] [Indexed: 05/22/2023]
Abstract
Rising rate of MSW generation and unscientific disposal in the open dumping sites are responsible for emission of high concentrations of methane in developing countries. IPCC Default method (DM), First-order decay (FOD) and LandGEM were used to estimate methane emissions from the unengineered landfill sites of Delhi-Okhla, Bhalswa and Ghazipur between 1984 and 2015. During the period, the total CH4 emissions was found to be 1288.99, 311.18, 779.32 Gg from the 3 landfill sites of Delhi as predicted by DM, FOD and LandGEM respectively. The energy generation potential from methane for the year 2015 was found to vary from 4.16 × 108 to 9.86 × 108 MJ for Ghazipur, 2.08 × 108 to 4.06 × 108 MJ for Okhla and 3.42 × 108 to 8.11 × 108 MJ for Bhalswa. Efficient utilization of methane from the landfills as an energy source can be a sustainable waste management option.
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144
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Zhang M, Wang Y, Liang P, Zhao X, Liang M, Zhou B. Combined photoelectrocatalytic microbial fuel cell (PEC-MFC) degradation of refractory organic pollutants and in-situ electricity utilization. CHEMOSPHERE 2019; 214:669-678. [PMID: 30292049 DOI: 10.1016/j.chemosphere.2018.09.085] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 09/14/2018] [Accepted: 09/15/2018] [Indexed: 06/08/2023]
Abstract
A new photoelectrocatalytic (PEC) and microbial fuel cell (MFC) process was developed and applied to simultaneously remove refractory organic pollutants (i.e., phenol and aniline) from wastewater while recovering energy for in-situ utilization. The current generated by the MFC process was applied to drive the PEC reaction. Compared with single PEC or MFC processes, the PEC-MFC combined process showed higher pollutant and chemical oxygen demand (COD) removal capacities and electricity production. Over 95% of the phenol or aniline was removed by these process, even at high initial concentrations. The COD removal efficiencies for phenol and aniline were ca. 96% (from 700 to 29 mg L-1) and 70% (from 165 to 49 mg L-1), respectively. Although the PEC process showed a limited contribution to phenol and aniline removals (16.5% and 43%, respectively), the utilization of PEC-treated phenol or aniline streams resulted in a MFC with higher voltage output, higher coulombic efficiency, maximal volumetric power density, and lower internal resistance as compared to untreated water. High-performance liquid chromatography coupled with mass spectrometry measurements revealed quinones/hydroquinones and low molecular weight organic acids to be produced as intermediates after the PEC process, which could improve the production of electricity in the MFC.
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145
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Sari MA, Badruzzaman M, Cherchi C, Swindle M, Ajami N, Jacangelo JG. Recent innovations and trends in in-conduit hydropower technologies and their applications in water distribution systems. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2018; 228:416-428. [PMID: 30243077 DOI: 10.1016/j.jenvman.2018.08.078] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 07/26/2018] [Accepted: 08/20/2018] [Indexed: 06/08/2023]
Abstract
Water conduits have a large untapped potential to recapture energy for small hydroelectric generation, which can substantially reduce grid electricity consumption and/or provide renewable energy to water agencies. Over the past decade, there has been a recent technological renaissance in off-the-shelf "water-to-wire" turbine technologies including reaction, impulse, and hydrokinetic turbines that target the sub 1-MW in-conduit hydroelectric market. However, adoption of small hydropower technologies remain limited in water and wastewater utility sector, possibly due to the lack of market penetration and exposure. Moreover, information about newly developed small hydropower technologies in the last 5-10 years for in-conduit applications are highly dispersed in the literature. As such, this paper is a comprehensive review on recent technological innovations and trends in hydropower generation from water conduits. Sixteen turbine technologies (eight conventional turbines and eight emerging turbines) are assessed and compared based on their potential benefits and challenges, technology readiness levels, as well as potential sites for installations in diversion structures, potable and irrigation water distribution systems, and wastewater outfalls. Although conventional turbines are considered to be more robust, the modular design of the newer turbines potentially offers a more cost effective solution and better scaling-up capability. Selected case studies on the application of conventional and new turbines for pipelines are also are also reviewed and discussed.
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146
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Yang L, Si B, Tan X, Chu H, Zhou X, Zhang Y, Zhang Y, Zhao F. Integrated anaerobic digestion and algae cultivation for energy recovery and nutrient supply from post-hydrothermal liquefaction wastewater. BIORESOURCE TECHNOLOGY 2018; 266:349-356. [PMID: 29982057 DOI: 10.1016/j.biortech.2018.06.083] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 06/23/2018] [Accepted: 06/25/2018] [Indexed: 06/08/2023]
Abstract
Post-hydrothermal liquefaction wastewater (PHWW), which contains approximately 80% of original feedstock resources, shows great potential to achieve sustainable development of an environment-enhancing energy system. A combination of anaerobic digestion and algae cultivation was proposed for methane recovery and nutrient supply from PHWW. Granular activated carbon (GAC) and ozone were used to enhance energy recovery from the PHWW. The results indicated that with GAC addition, the maximum methane yield increased by 67.7%-228 mL/g CODremoval. In addition, Chlorella vulgaris displayed optimal growth in a 5-fold diluted digestate with a 2.32 g/L maximum biomass content and 180 mg/(L·d) biomass production rate. The total energy yield was 565 kJ/g COD, which was 27.4 times higher than that without GAC. Integration of anaerobic digestion and algae cultivation, particularly with GAC addition during fermentation, is a feasible and advantageous process for energy recovery from PHWW.
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147
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Chen J. Bio-oil production from hydrothermal liquefaction of Pteris vittata L.: Effects of operating temperatures and energy recovery. BIORESOURCE TECHNOLOGY 2018; 265:320-327. [PMID: 29909362 DOI: 10.1016/j.biortech.2018.06.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Revised: 06/05/2018] [Accepted: 06/06/2018] [Indexed: 06/08/2023]
Abstract
Hyper-accumulator biomass, Pteris vittata L., was hydrothermally converted into bio-oils via hydrothermal liquefaction (HTL) in sub-supercritical water. The distributions and characterizations of various products as well as energy recovery under different temperatures (250-390 °C) were investigated. The highest bio-oil yield of 16.88% was obtained at 350 °C with the hydrothermal conversion of 61.79%, where the bio-oil was dominated by alcohols, esters, phenols, ketones and acidic compounds. The higher heating values of bio-oil were in the range of 19.93-35.45 MJ/kg with a H/C ratio of 1.26-1.46, illustrating its high energy density and potential for use as an ideal liquid fuel. The main gaseous products were CO2, H2, CO, and CH4 with the H2 yield peaking at 22.94%. The total energy recovery from bio-oils and solid residues fell within the range of 37.72-45.10%, highlighting the potential of HTL to convert hyper-accumulator biomass into valuable fuels with high conversion efficiency.
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Muhammad N, Nafees M, Hussain R, Khan MH, Jehan S, Ullah U. Pollution and energy reduction strategy in soft drink industries. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:28153-28159. [PMID: 30069783 DOI: 10.1007/s11356-018-2861-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 07/27/2018] [Indexed: 06/08/2023]
Abstract
The present study was conducted on soft drink industry with the objective to reduce wastewater pollution through end-of-pipe treatment and controlling energy loss through steam pipeline insulation approach. For this purpose, the main operation and manufacturing steps were examined. Wastewater was analyzed for 10 physicochemical parameters. Among these parameters, total dissolved solids (TDS), total suspended solids (TSS) and chemical oxygen demand (COD) were above their permissible level of Pakistan national environmental quality standards (Pak NEQS). For wastewater treatment, sedimentation, flocculation, coagulation and adsorption were tested. The active study reduces the pollution load up to 48%. After treatment, all the parameters were below the Pak NEQS level. To reduce the energy loss and economic benefits, the steam pipeline system was galvanized using glass wool, sheet and paper. Through galvanizing, 91.4% of energy was recovered and reduced an extra cost of 91.5%. The net saving of energy and cost are 312 GJ and114098 Rs/year, respectively. The study recommends end off pipe treatment and insulation of bare pipeline system for soft drink industries.
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Haupt M, Kägi T, Hellweg S. Modular life cycle assessment of municipal solid waste management. WASTE MANAGEMENT (NEW YORK, N.Y.) 2018; 79:815-827. [PMID: 29861114 DOI: 10.1016/j.wasman.2018.03.035] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 02/27/2018] [Accepted: 03/23/2018] [Indexed: 06/08/2023]
Abstract
Life cycle assessment (LCA) is commonly applied to examine the environmental performance of waste management systems. The system boundaries are, however, often limited to either one tonne of material or to specific waste treatments and are, therefore, lacking a systems perspective. Here, a framework is proposed to assess complete waste management systems based on actual waste flows, assessed with a detailed material flow analysis (MFA) in a modular MFA/LCA approach. The transformation of the MFA into a product-process-matrix facilitates a direct link between MFA and LCA, therefore allowing for the assessment of variations in flows. To allow for an up-to-date and geographically specific assessment, 190 LCA modules were set up based on primary industrial data and the ecoinvent database. The LCA modules show where there have been improvements in different recycling processes over the past years (e.g. for paper recycling) and highlight that, from an environmental perspective, closed-loop recycling is not always preferable to open-loop recycling. In a case study, the Swiss municipal solid waste management system, of which there is already a detailed MFA, was modeled using the new LCA modules and applying the modular MFA/LCA approach. Five different mass flow distribution scenarios for the Swiss municipal solid waste management system were assessed to show the environmental impact of political measures and to test the sensitivity of the results to key parameters. The results of the case study highlight the importance of the dominant fractions in the overall environmental impacts assessment; while the metal fraction has the highest impact on a per kilogram basis, paper, cardboard, glass and mixed municipal solid waste were found to dominate the environmental impacts of the Swiss waste management system due to their mass. The scenarios also highlight the importance of the energy efficiency of municipal solid waste incineration plants and the credits from material substitution as key variables. In countries with advanced waste management systems such as Switzerland, there is limited improvement potential with further increases in recycling rates. In these cases, the focus of political measures should be laid on (i) the utilization of secondary materials in applications where they replace high-impact primary production, and (ii) an increased recovery of energy in waste-to-energy plants.
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Stazi V, Tomei MC. Enhancing anaerobic treatment of domestic wastewater: State of the art, innovative technologies and future perspectives. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 635:78-91. [PMID: 29660730 DOI: 10.1016/j.scitotenv.2018.04.071] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 04/05/2018] [Accepted: 04/05/2018] [Indexed: 06/08/2023]
Abstract
Recent concerns over public health, environmental protection, and resource recovery have induced to look at domestic wastewater more as a resource than as a waste. Anaerobic treatment, owing to attractive advantages of energy saving, biogas recovery and lower sludge production, has been suggested as an alternative technology to the traditional practice of aerobic wastewater treatment, which is energy intensive, produces high excess of sludge, and fails to recover the potential resources available in wastewater. Sewage treatment by high-rate anaerobic processes has been widely reported over the last decades as an attractive method for providing a good quality effluent. Among the available high-rate anaerobic technologies, membrane bioreactors feature many advantages over aerobic treatment and conventional anaerobic systems, since high treatment efficiency, high quality effluent, pathogens retention and recycling of nutrients, were generally achieved. The objective of this paper is to review the currently available knowledge on anaerobic domestic wastewater treatment for the mostly applied high-rate systems and membrane bioreactors, presenting benefits and drawbacks, and focusing on the most promising emerging technologies, which need more investigation for their scale-up.
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