Unit Energy Consumption, Production, and Cost of Innovative Treatment Systems of Different Wastewater Streams

Innovative technologies such as micro-sieving, Anammox, and up-flow anaerobic sludge blanket (UASB) hold the key in the sustainable design of Water Resource Recovery Facility (WRRF). In the past, assessment metrics on the effectiveness and economic feasibility of these technologies have not been systematically investigated. According to the twelve design principles of Sustainable Environmental Engineering, Unit energy and cost metrics could provide universal benchmarks in the design of WRRF. Therefore, the objectives of this study are to design innovative WRRF systems to achieve energy positive. These WRRFs were modeled by developing an Excel model to estimate the unit energy metrics. Database of different wastewater quality was developed according to literature data. An Excel model was also developed to estimate the cost due to the energy saving of innovative systems. In treating young, medium, and old leachate, systems with the innovative technologies could save the unit energy consumption by 2.24-4.07 kWh/kg Nremoved and the unit cost by $0.86-2.09/kg CODremoved than conventional technologies. Treatment of young leachate costs less than other leachate in terms of per kg COD removed. Although micro-sieving decreases CH4 production, it reduces the size of the UASB. As a result, micro-sieving could reduce the unit cost by 27$/kg CODremoved, respectively. Therefore, meat processing wastewater can be the most efficiently treated by using innovative technologies due to its high biodegradability. For WWTPs in China, anaerobic-oxic plus anaerobic-anoxic-oxic, oxidation ditch, and sequencing batch reactor were the main technologies. Due to lower energy consumption, SBR is the best technology in small and medium WWTPs in China

Anaerobic membrane bioreactors for future green bioprocesses

© 2016 American Society of Civil Engineers. This chapter focuses on the comprehensive overview of the recent progress in anaerobic membrane bioreactor (AnMBR) applications, including the fundamental aspects and development of AnMBR processes. For a future green bioprocess, the chapter discusses the application development of AnMBRs in domestic and industrial wastewater treatment, opportunities for biogas production and waste minimization and membrane fouling researches. The anaerobic treatment processes are known to have the inherent advantages over the aerobic counterparts, such as sludge minimization and energy savings. The key competitive advantages of AnMBRs over conventional aerobic and anaerobic processes include total biomass retention, excellent effluent quality, bioenergy recovery, smaller footprint, lower energy consumption, high efficiency of wastewater treatment, and strong ability of handling fluctuation in influent quality. Biogas recovery represents one of the key green features of AnMBR technology, particularly for submerged AnMBR (SAnMBR). The compact configure of SAnMBR allows for more convenient collection of biogas

Tratamiento de un agua residual industrial por digestión anaerobia empleando un calentador solar como energía renovable para el control de temperaturar

Las energías limpias son las únicas energías renovables capaces de reemplazar el uso de los combustibles fósiles. El uso de las energías limpias en las Plantas de Tratamiento de Aguas Residuales disminuye los costos de operación. En el presente trabajo,un calentador solar se empleó para controlar la temperatura de un reactor UASB con el propósito de depurar un agua residual industrial compleja por digestión anaerobia. El reactor se operó con tres temperaturas (16, 20 y 30 ºC), 11 g DQO/L-d y un TRH de 6 h. Además, se evaluó el efecto de un co-sustrato en la degradación de la DQO, en cultivos lote. En el estado estacionario,las eficiencias de remoción de la DQO fueron de 8.6, 20 y 40%, para las temperaturas de 16, 20 y 30 ºC, respectivamente. El incremento de la temperatura mejoró la producción de metano, alcanzando 257±8.6 ml CH4/g DQO removida. La adición de 200 y 400 mg glucosa/L en cultivos lote mejoraron las eficiencias de remoción y la tasa de consumo de la DQO. Finalmente, un calentador solar podría ser una tecnología factible para controlar la temperatura de un reactor UASB y mejorar la eficiencia de degradación de la materia orgánica

Anaerobic Digestion Of Recycled Paper Mill Effluent (Rpme) Using Modified Anaerobic Hybrid Baffled (Mahb) Reactor

Reaktor bersesekat hibrid anaerob terubah suai (MAHB) adalah reaktor yang sering digunakan untuk biopenukaran bahan organik di dalam industri rawatan sisa kumbahan disamping menghasilkan metana gas dengan bantuan mikroorganisma anaerobik. Dalam projek ini, reaktor MAHB berisipadu 58 L telah berjaya direka dan dikendalikan untuk merawat efluen kilang kertas kitar semula (RPME). Proses permulaan (start up) berjaya dicapai dalam tempoh 28 hari, dengan menghasilkan 65.97% biogas (0.31 L) dan menyingkirkan keperluan oksigen kimia (COD) yang tinggi (86.41%) serta menunjukkan nilai pH yang stabil (7.2 – 7.4). Selain itu, prestasi reaktor MAHB juga dikaji untuk proses berterusan, prestasi reaktor petak kecil “compartment”, kadar kemasukan organik (OLR) dan nilai bekalan kepekatan COD berbeza. Keputusan menunjukkan bahawa reaktor MAHB berjaya beroperasi pada proses yang berterusan dan setiap petak kecil bertindak sebagai reaktor individu yang menyumbang kepada kadar pengeluaran metana yang tinggi. Tambahan pula, pemasangan sesekat secara berdiri dan tergantung ke dalam reactor MAHB menyediakan pencampuran sempurna antara biomas dan substrat. Sesekat yang mempunyai saiz dan bentuk yang berbeza juga menyumbang kepada pertumbuhan mikroorganisma yang berbeza dalam setiap petak yang berbeza yang membantu pemisahan fasa. Sesekat bertangga darjah 35° dengan tangga mendatar di petak 1 menunjukkan bentuk sesekat yang menyumbang kepada prestasi yang lebih tinggi. Kesan OLR dan kepekatan bekalan COD menunjukkan bahawa MAHB reaktor memberikan prestasi tinggi dari segi kadar pengeluaran metana dan kecekapan penyingkiran COD apabila OLR dan kepekatan COD meningkat sehingga ia mencapai keadaan optimum. Interaksi dan pengoptimuman penghadaman RPME telah dilakukan menggunakan kaedah permukaan sambutan (RSM) dengan dua pembolehubah (masa penahanan hidraulik (HRT) dan kepekatan bekalan COD) dan tiga respon (kepekatan COD, kepekatan lignin dan kadar penghasilan metana gas). Keputusan ujikaji ini menunjukkan optimum penyingkiran COD sebanyak 97.42 % dan lignin pada 59.59 % serta penghasilan gas metana sebanyak 8.07 L CH4 hari-1 adalah pada HRT 3.93 hari dan bekalan kepekatan COD sebanyak 3020.88 mg L-1. Penemuan ini adalah hampir sama dengan ramalan optimum oleh pemasangan analisis menggunakan rangkaian neural tiruan (ANN) untuk penyingkiran COD (98.16%), penyingkiran lignin (77.29%) dan pengeluran metana gas (8.34 L hari-1). Kajian kinetik pada fasa pencernaan anaerobik yang berbeza mendedahkan bahawa hidrolisis adalah proses kadar mengehadkan “rate limiting step”. Model kinetic Monod dan Contois menunjukkan bahawa kedua-dua memberi ramalan yangmemuaskan dengan kadar maksimum pertumbuhan spesifik mikrob (µ.max) masingmasing adalah 1.476 dan 0.6796 L. Selain kinetik, tingkah laku hidrodinamik menunjukkan bahawa ruang mati “dead space” dalam MAHB reaktor adalah antara 10.13-10.39% untuk air paip dan 1.45 - 5% untuk RPME. Corak pergerakan hidraulik dalam reaktor MAHB menunjukkan perantara antara aliran pasang dan pengantara yang lebih dekat dengan palam aliran berbanding aliran perantaraan dengan kecekapan hidraulik antara 0.20-0.64 untuk air paip dan 1.00-3.95 untuk RPME. ________________________________________________________________________________________________________________________ Modified anaerobic hybrid baffled (MAHB) reactor is a recent reactor that widely used for rapid bioconversion of organic matter in industrial wastewater treatment process to produce methane with the help of anaerobic microorganism. A pilot scale MAHB reactor (58 L) was successfully fabricated and operated for treatment of recycled paper mill effluent (RPME). A successful start up process were achieved less than a month (28 days) with a high COD removal efficiency of 86.41 % and pH values between 7.2 – 7.4 at steady state condition. The methane content at the end of start up was recorded at 65.97 % with a total biogas volume of 0.31 L. During the process study, the MAHB reactor were run to study the performance of MAHB reactor during continuous feeding, compartment-wise profile, different organic loading rates (OLRs) and also different feeding concentrations. Result shows that the MAHB reactor successfully operated at continuous process and each compartments act as an individual reactor which gives high methane production rate. Furthermore, installation of standing and hanging baffles and introduction of packing materials into MAHB reactor provides perfect mixing between biomass and substrates. The different size and shaped of baffles also contributes to different growth of microorganism in each different compartments that leds to phase separations. The 35° ladder with inclining horizontal ladder baffled in Compartment 1 shows the best shaped of baffle that contributes to higher performances of MAHB. The effect of OLR and feeding COD concentrations shows that MAHB reactor gives high performance in terms of methane production rates and xxviii COD removal efficiencies as the OLR and feeding COD concentration increases until it reach its optimum condition. Interaction and optimization of RPME digestion were conducted using D-optimal design of response surface methodology (RSM) with two variables i.e. hydraulic retention time (HRT) and feeding COD concentrations. The optimum conditions that yield a highest COD and lignin removal efficiency as well as methane production rate was HRT of 3.93 days, feeding COD concentration of 3020.88 mg L-1 that gaves a COD removal efficiency of 97.42 %, lignin removal efficiency of 59.59 % and methane production rate of 8.07 L CH4 day-1 with desirability value of 0.897. This finding were in close agreement with the predicted optimum COD removal efficiecncy, lignin removal efficiency and methane production rate predicted by fitting analysis using artificial neural network (ANN). The optimum predicted output obained by ANN are 98.16 %, 77.29 % and 8.34 L day-1 for COD removal, lignin removal and methane production rate, respectively. Different phases of anaerobic digestion were undergo kinetic studies which revealed that hydrolysis is the rate limiting step. Applied Monod and Contois kinetic models, it shows that both give satisfactory prediction with (µ.max) values of 1.476 and 0.6796 L day-1, respectively. Instead of kinetics, the hydrodynamic behaviours shows that dead space in MAHB reactor is between 10.13 – 10.39 % for tap water and 1.45 – 5 % for RPME. The flow pattern within the MAHB reactors showed an intermediary between the plug flows and intermediate which closer to plug flow compared to intermediate flow with a hydraulic efficiency between 0.20 – 0.64 for tap water and 1.00 – 3.95 for RPME

Review of Continuous Fermentative Hydrogen-Producing Bioreactors from Complex Wastewater

In recent years, the production of hydrogen through dark fermentation has become increasingly popular because it is a sustainable approach to produce clean energy. Thus, an evaluation of studies reported on hydrogen production from different complex wastewaters will be of immense importance in economizing production technologies. This work presents a review of the advances in the bioreactor and bioprocess design for biohydrogen production from different complex wastewaters. The biohydrogen production is discussed emphasizing the production metabolic pathways, bioreactor configuration and operation, organic loading rate (OLR), pretreatment of wastewater, as well as microbial diversity. Also, in this review, various bioreactor configurations and performance parameters including H2 yield (HY) and hydrogen production rate (HPR) are evaluated and presented. The work concludes with challenges and prospects of biohydrogen production and claims for more systematic and comprehensive studies on the subject

Perspectives on carbon materials as powerful catalysts in continuous anaerobic bioreactors

Supplementary data related to this article can be found at http:// dx.doi.org/10.1016/j.watres.2016.06.004.The catalytic effect of commercial microporous activated carbon (AC) and macroporous carbon nanotubes (CNT) is investigated in reductive bioreactions in continuous high rate anaerobic reactors, using the azo dye Acid Orange 10 (AO10) as model compound as electron acceptor and a mixture of VFA as electron donor. Size and concentration of carbon materials (CM) and hydraulic retention time (HRT) are assessed. CM increased the biological reduction rate of AO10, resulting in significantly higher colour removal, as compared to the control reactors. The highest efficiency, 98%, was achieved with a CNT diameter (d) lower than 0.25 mm, at a CNT concentration of 0.12 g per g of volatile solids (VS), a HRT of 10 h and resulted in a chemical oxygen demand (COD) removal of 85%. Reducing the HRT to 5 h, colour and COD removal in CM-mediated bioreactors were above 90% and 80%, respectively. In the control reactor, thought similar COD removal was achieved, AO10 decolourisation was just approximately 20%, demonstrating the ability of CM to significantly accelerate the reduction reactions in continuous bioreactors. AO10 reduction to the correspondent aromatic amines was proved by high performance liquid chromatography (HPLC). Colour decrease in the reactor treating a real effluent with CNT was the double comparatively to the reactor operated without CNT. The presence of AC in the reactor did not affect the microbial diversity, as compared to the control reactor, evidencing that the efficient reduction of AO10 was mainly due to AC rather than attributed to changes in the composition of the microbial communities.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01- 0145-FEDER-006684). Raquel Pereira had a fellowship (SFRH/BD/ 72388/2010) and Luciana Pereira has the fellowship (SFRH/BPD/ 110235/2015) from FCT. The authors thank the FCT exploratory EXPL/AAG-TEC/0898/2013 project