Influence of a new ornamental species (Spathiphyllum blandum) on the removal of COD, nitrogen, phosphorus and fecal coliforms: a mesocosm wetland study with PET and tezontle substrates

Abstract The objective of this study was to evaluate the influence of a new species of plant (Spathiphyllum blandum) in the elimination of chemical oxygen demand (COD), nitrogen, phosphorus and fecal coliforms (FCs) in mesocosms of wetlands with polyethylene terephthalate (PET) and tezontle substrates under a tropical climate. The experiments were developed at the mesocosm level in 20 experimental units; 10 were planted with Spathiphyllum blandum, five in PET substrates and five in tezontle, and 10 more were used as controls without vegetation, of which five contained tezontle and five contained PET. The systems were fed with contaminated water from the river Sordo, with a hydraulic retention time of 3 days for 12 months; samples were taken in the influent and effluents of the mesocosms every 2 weeks, with the purpose of evaluating the removal of contaminants. The results showed that presence of this species tended to improve or significantly improved the removal of COD, NH4-N, PO4-P, and FCs by 7%, 16%, 29% and 12%, respectively. It was also possible to confirm that the presence of this species reduced the rate of denitrification. These results confirm that in developing countries it is feasible to find new wetland species to be used for wastewater phytoremediation.

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Studies on the Homalomeneae (Araceae) of Borneo XXVI—A new and highly ornamental species of Homalomena [Punctulata Clade] from Triassic-Jurassic karst formations in SW Sarawak

Phytotaxa ◽

10.11646/phytotaxa.455.3.4 ◽

2020 ◽

Vol 455 (3) ◽

pp. 214-220

Author(s):

WONG SIN YENG ◽

PETER C. BOYCE

Keyword(s):

New Species ◽

A New Species ◽

Ornamental Species

Homalomena benedikii is described and illustrated as a new species from Serian Division, SW Sarawak, where it is restricted to forested Triassic-Jurassic karst formations, and compared with the two most similar described species H. cowleyae and H. imitator, from shales in NE Sarawak and Brunei, and C Sarawak, respectively.

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Working Parameters Optimization of Hydrolysis-acidogenesis reactor in two stage anaerobic digestion of slaughterhouse Wastewater for Biogas Production

10.21203/rs.2.20690/v1 ◽

2020 ◽

Author(s):

Dejene Tsegaye Bedane ◽

Mohammed Mazharuddin Khan ◽

Seyoum Leta Asfaw

Keyword(s):

Anaerobic Digestion ◽

Working Conditions ◽

Retention Time ◽

Hydraulic Retention Time ◽

Loading Rate ◽

Oxygen Demand ◽

Organic Loading Rate ◽

Organic Loading ◽

Slaughterhouse Wastewater ◽

Working Parameters

Abstract Background : Wastewater from agro-industries such as slaughterhouse is typical organic wastewater with high value of biochemical oxygen demand, chemical oxygen demand, biological organic nutrients (Nitrogen and phosphate) which are insoluble, slowly biodegradable solids, pathogenic and non-pathogenic bacteria and viruses, parasite eggs. Moreover it contains high protein and putrefies fast leading to environmental pollution problem. This indicates that slaughterhouses are among the most environmental polluting agro-industries. Anaerobic digestion is a sequence of metabolic steps involving consortiums of several microbial populations to form a complex metabolic interaction network resulting in the conversation of organic matter into methane (CH 4 ), carbon dioxide (CO 2 ) and other trace compounds. Separation of the phase permits the optimization of the organic loading rate and HRT based on the requirements of the microbial consortiums of each phase. The purpose of this study was to optimize the working conditions for the hydrolytic - acidogenic stage in two step/phase anaerobic digestion of slaughterhouse wastewater. The setup of the laboratory scale reactor was established at Center for Environmental Science, College of Natural Science with a total volume of 40 liter (36 liter working volume and 4 liter gas space). The working parameters for hydrolytic - acidogenic stage were optimized for six hydraulic retention time 1-6 days and equivalent organic loading rate of 5366.43 – 894.41 mg COD/L day to evaluate the effect of the working parameters on the performance of hydrolytic – acidogenic reactor. Result : The finding revealed that hydraulic retention time of 3 day with organic loading rate of 1,788.81 mg COD/L day was a as an optimal working conditions for the parameters under study for the hydrolytic - acidogenic stage. The degree of hydrolysis and acidification were mainly influenced by lower hydraulic retention time (higher organic loading rate) and highest values recorded were 63.92 % at hydraulic retention time of 3 day and 53.26% at hydraulic retention time of 2 day respectively. Conclusion : The finding of the present study indicated that at steady state the concentration of soluble chemical oxygen demand and total volatile fatty acids increase as hydraulic retention time decreased or organic loading rate increased from 1 day hydraulic retention time to 3 day hydraulic retention time and decreases as hydraulic retention time increase from 4 to 6 day. The lowest concentration of NH 4 + -N and highest degree of acidification was also achieved at hydraulic retention time of 3 day. Therefore, it can be concluded that hydraulic retention time of 3 day/organic loading rate of 1,788.81 mg COD/L .day was selected as an optimal working condition for the high performance and stability during the two stage anaerobic digestion of slaughterhouse wastewater for the hydrolytic-acidogenic stage under mesophilic temperature range selected (37.5℃). Keywords : Slaughterhouse Wastewater, Hydrolytic – Acidogenic, Two Phase Anaerobic Digestion, Optimal Condition, Agro-processing wastewater

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Effect of hydraulic retention time on chemical oxygen demand and total nitrogen removal in intermittently aerated constructed wetlands

Ambiente e Agua - An Interdisciplinary Journal of Applied Science ◽

10.4136/ambi-agua.2504 ◽

2020 ◽

Vol 15 (3) ◽

pp. 1 ◽

Cited By ~ 1

Author(s):

Isabela Pires da Silva ◽

Gabriela Barbosa da Costa ◽

João Gabriel Thomaz Queluz ◽

Marcelo Loureiro Garcia

Keyword(s):

Chemical Oxygen Demand ◽

Constructed Wetlands ◽

Total Nitrogen ◽

Total Phosphorus ◽

Constructed Wetland ◽

Retention Time ◽

Hydraulic Retention Time ◽

Subsurface Flow ◽

Oxygen Demand ◽

Intermittent Aeration

This study evaluated the effect of hydraulic retention time on chemical oxygen demand (COD) and total nitrogen (TN) removal in an intermittently aerated constructed wetlands. Two horizontal subsurface-flow constructed wetlands were used: one without aeration and the other aerated intermittently (1 hour with aeration/7 hours without aeration). Both systems were evaluated treating domestic wastewater produced synthetically. The flow rate into the two CWs was 8.6 L day-1 having a hydraulic retention time of 3 days. The results show that the intermittently aerated constructed wetland were highly efficient in removing COD (98.25%), TN (83.60%) and total phosphorus (78.10%), while the non-aerated constructed wetland showed lower efficiencies in the removal of COD (93.89%), TN (48.60%) and total phosphorus (58.66). These results indicate, therefore, that intermittent aeration allows the simultaneous occurrence of nitrification and denitrification processes, improving the removal of TN in horizontal subsurface-flow constructed wetlands. In addition, the use of intermittent aeration also improves the performance of constructed wetlands in removing COD and total phosphorus.

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Optimising the Hydraulic Retention Time in a Pilot-Scale Microbial Electrolysis Cell to Achieve High Volumetric Treatment Rates Using Concentrated Domestic Wastewater

Molecules ◽

10.3390/molecules25122945 ◽

2020 ◽

Vol 25 (12) ◽

pp. 2945 ◽

Cited By ~ 3

Author(s):

Daniel D. Leicester ◽

Jaime M. Amezaga ◽

Andrew Moore ◽

Elizabeth S. Heidrich

Keyword(s):

Retention Time ◽

Hydraulic Retention Time ◽

Oxygen Demand ◽

Domestic Wastewater ◽

Direct Analysis ◽

Pilot Scale ◽

Electrolysis Cell ◽

Treatment Technique ◽

Microbial Electrolysis Cell ◽

Microbial Electrolysis

Bioelectrochemical systems (BES) have the potential to deliver energy-neutral wastewater treatment. Pilot-scale tests have proven that they can operate at low temperatures with real wastewaters. However, volumetric treatment rates (VTRs) have been low, reducing the ability for this technology to compete with activated sludge (AS). This paper describes a pilot-scale microbial electrolysis cell (MEC) operated in continuous flow for 6 months. The reactor was fed return sludge liquor, the concentrated filtrate of anaerobic digestion sludge that has a high chemical oxygen demand (COD). The use of a wastewater with increased soluble organics, along with optimisation of the hydraulic retention time (HRT), resulted in the highest VTR achieved by a pilot-scale MEC treating real wastewater. Peak HRT was 0.5-days, resulting in an average VTR of 3.82 kgCOD/m3∙day and a 55% COD removal efficiency. Finally, using the data obtained, a direct analysis of the potential savings from the reduced loading on AS was then made. Theoretical calculation of the required tank size, with the estimated costs and savings, indicates that the use of an MEC as a return sludge liquor pre-treatment technique could result in an industrially viable system.

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Efektivitas IPAL portabel sebagai alternatif pengelolaan limbah cair domestik

Jurnal Pengelolaan Lingkungan Berkelanjutan (Journal of Environmental Sustainability Management) ◽

10.36813/jplb.3.1.235-243 ◽

2019 ◽

pp. 235-243

Author(s):

Ika Bagus Priyambada ◽

Purwono Purwono

Keyword(s):

Chemical Oxygen Demand ◽

Retention Time ◽

Hydraulic Retention Time ◽

Oxygen Demand

Di Indonesia, selain sebagai saluran air alamiah, sungai sering pula digunakan sebagai tempat pembuangan air limbah kegiatan rumah tangga (domestik). Penggunaan teknologi yang efisien dan alami merupakan solusi sederhana dan murah untuk mengolah air limbah domestik dengan sistem desentralisasi. Tujuan penelitian ini adalah mengolah air limbah domestik menggunakan IPAL portabel dengan dimensi kecil, sehingga aplikatif untuk skala rumah tangga. Penelitian dilakukan di Laboratorium Lingkungan, Departemen Teknik Lingkungan, Universitas Diponegoro selama 3 bulan. Metode penelitian menggunakan IPAL portabel untuk mengolah air limbah domestik skala rumah tangga dengan sistem kontinu. Limbah domestik berasal dari kantin kampus Universitas Diponegoro. IPAL portabel menggunakan sistem kombinasi anaerob-aerob yang dilengkapi dengan bak penampung limbah awal, bak penangkap lemak dan bak efluen. Waktu tinggal hidrolis atau Hydraulic Retention Time (HRT) dilakukan pada 3 variasi yaitu 4 jam, 8 jam dan 12 jam. Hasil penelitian menunjukkan bahwa konsentrasi amoniak mengalami penurunan terbesar pada HRT 12 jam dengan efisiensi penyisihan sebesar 60%. Konsentrasi awal sebesar 40,99 mg/l turun menjadi 16,4 mg/l. Konsentrasi Chemical Oxygen Demand (COD) dan minyak & lemak juga mengalami penurunan terbesar pada HRT 12 jam, masing-masing turun sebesar 71% dan 91% dari konsentrasi awal. IPAL portabel ini paling efektif dalam menyisihkan minyak & lemak.

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Dynamics of Archaeal and Bacterial Communities in Response to Variations of Hydraulic Retention Time in an Integrated Anaerobic Fluidized-Bed Membrane Bioreactor Treating Benzothiazole Wastewater

Archaea ◽

10.1155/2018/9210534 ◽

2018 ◽

Vol 2018 ◽

pp. 1-11 ◽

Cited By ~ 1

Author(s):

Yue Li ◽

Qi Hu ◽

Da-Wen Gao

Keyword(s):

Fluidized Bed ◽

Removal Efficiency ◽

Retention Time ◽

Membrane Fouling ◽

Membrane Bioreactor ◽

Hydraulic Retention Time ◽

Oxygen Demand ◽

High Strength ◽

Service Period ◽

Miseq Platform

An integrated anaerobic fluidized-bed membrane bioreactor (IAFMBR) was investigated to treat synthetic high-strength benzothiazole wastewater (50 mg/L) at a hydraulic retention time (HRT) of 24, 18, and 12 h. The chemical oxygen demand (COD) removal efficiency (from 93.6% to 90.9%), the methane percentage (from 70.9% to 69.27%), and the methane yield (from 0.309 m3 CH4/kg·CODremoved to 0.316 m3 CH4/kg·CODremoved) were not affected by decreasing HRTs. However, it had an adverse effect on membrane fouling (decreasing service period from 5.3 d to 3.2 d) and benzothiazole removal efficiency (reducing it from 97.5% to 82.3%). Three sludge samples that were collected on day 185, day 240, and day 297 were analyzed using an Illumina® MiSeq platform. It is striking that the dominant genus of archaea was always Methanosaeta despite of HRTs. The proportions of Methanosaeta were 80.6% (HRT 24), 91.9% (HRT 18), and 91.2% (HRT 12). The dominant bacterial genera were Clostridium in proportions of 23.9% (HRT 24), 16.4% (HRT 18), and 15.3% (HRT 12), respectively.

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Treatment of Domestic Strength Wastewater with Anaerobic Hybrid Reactors

Water Quality Research Journal ◽

10.2166/wqrj.1987.038 ◽

1987 ◽

Vol 22 (3) ◽

pp. 474-490 ◽

Cited By ~ 3

Author(s):

R.L. Droste ◽

S.R. Guiot ◽

S.S. Gorur ◽

K.J. Kennedy

Keyword(s):

Retention Time ◽

Suspended Solids ◽

Hydraulic Retention Time ◽

Oxygen Demand ◽

Anaerobic Treatment ◽

Synthetic Wastewater ◽

Solids Retention Time ◽

Solids Retention ◽

Removal Efficiencies ◽

Hybrid Reactors

Abstract Anaerobic treatment of dilute synthetic wastewater (300-1,000 mg chemical oxygen demand/L using laboratory upflow sludge blanket filter reactors with and without effluent recycle is described. Treatment of dilute synthetic wastewater at hydraulic retention times less than 1 and 2 h in reactors without and with recycle, respectively, resulted in biomass washout as the solids retention time decreased to less than 12 d. Reseeding would be required to operate at these critical hydraulic retention times for extended periods. Treatment of dilute synthetic wastewater at hydraulic retention times between 3-12 h resulted in soluble COD removal efficiencies between 84-95% treating 300 mg COD/L. At a 3 h hydraulic retention time, solids retention time of 80 d and stable reactor biomass concentrations of 25 g volatile suspended solids/L were maintained.

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Enhancement of nitrate removal in synthetic groundwater using wheat rice stone

Water Science & Technology ◽

10.2166/wst.2012.279 ◽

2012 ◽

Vol 66 (9) ◽

pp. 1900-1907 ◽

Cited By ~ 7

Author(s):

Siqi Hong ◽

Jianmei Zhang ◽

Chuanping Feng ◽

Baogang Zhang ◽

Puxi Ma

Keyword(s):

Trace Elements ◽

Activated Carbon ◽

Retention Time ◽

Hydraulic Retention Time ◽

Nitrate Removal ◽

Oxygen Demand ◽

Nitrite Accumulation ◽

Synthetic Groundwater ◽

Biofilm Carriers ◽

Growth Of Bacteria

To enhance the efficiency of nitrate removal from synthetic groundwater, wheat rice stone (WRS) and granular activated carbon (GAC) were employed as biofilm carriers for denitrification under different HRT (hydraulic retention time) and C/N ratios. Four different ratios of GAC to WRS (0, 0.5, 1.0, and 2.0) were investigated to determine the most appropriate ratio of GAC and WRS. The NO3−-N, NO2−-N, COD levels and pH of the effluent were also investigated under various HRT and C/N ratios. The results showed that the column at a GAC/WRS ratio of 1.0 performed best under a C/N ratio of 0.9 and an HRT of 8 h, with 99% nitrate being removed. In addition, little nitrite accumulation and chemical oxygen demand (COD) were observed in effluent under these conditions. These results demonstrated that, with no addition of phosphor in the influent, the nitrate removal efficiency can be enhanced by WRS because WRS can leach trace elements and phosphor to promote the growth of bacteria.

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Start-Up Operation and Hydraulic Retention Time Selectivity for Palm Oil Mill Wastewater at Mesophilic Temperature in Anaerobic Suspended Growth Closed Bioreactor

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.955-959.1330 ◽

2014 ◽

Vol 955-959 ◽

pp. 1330-1334

Author(s):

Yee Shian Wong ◽

Tjoon Tow Teng ◽

Soon An Ong ◽

Morad Norhashimah ◽

Mohd Rafatullah

Keyword(s):

Palm Oil ◽

Retention Time ◽

Anaerobic Degradation ◽

Hydraulic Retention Time ◽

Biogas Production ◽

Oxygen Demand ◽

Anaerobic Bioreactor ◽

Start Up ◽

Palm Oil Mill ◽

Pome Wastewater

The start-up operation and hydraulic retention time (HRT) selectivity of anaerobic degradation for palm oil mill effluent (POME) wastewater was carried out in an anaerobic bioreactor. HRT between 35 and 5 days were investigated. The start-up process for the anaerobic degradation of POME wastewater was found to be completed after 40 days of operation. This study also recommended that the anaerobic degradation of POME wastewater should be operated at the HRT between 35 and 10 days without acid risk. The performance of anaerobic bioreactor could reach 90.55% - 87.55% chemical oxygen demand (COD) reduction, 0.06 - 0.40 ratio between volatile fatty acid (VFA) and alkalinity (Alk), -368.2 mV to-445.80 mV of oxygen reduction potential (ORP) and 9.08 - 37.2 liters of biogas production, respectively.

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The effect of CO2 addition and hydraulic retention time on pathogens removal in HRAPs

Water Science & Technology ◽

10.2166/wst.2020.255 ◽

2020 ◽

Vol 82 (6) ◽

pp. 1184-1192

Author(s):

Graziele Ruas ◽

Sarah Lacerda Farias ◽

Priscila G. Scarcelli ◽

Mayara L. Serejo ◽

Marc A. Boncz

Keyword(s):

Retention Time ◽

Hydraulic Retention Time ◽

Oxygen Demand ◽

Biomass Productivity ◽

High Rate ◽

Nitrogen And Phosphorus ◽

Total Organic Nitrogen ◽

E Coli ◽

Bacterial Removal ◽

Co2 Addition

Abstract The influence of CO2 addition and hydraulic retention time (5 and 7 days) on removal of Pseudomonas aeruginosa, Clostridium perfringens, Staphylococcus sp., Enterococcus sp., and Escherichia coli was evaluated in a system with three parallel 21 L high rate algal ponds. Both the addition of CO2 and an increase in HRT had no significant influence on bacterial removal, but bacterial removal was higher than found in previous studies. The removal was 3.4–3.8, 2.5–3.7, 2.6–3.1, 2.2–2.6 and 1.3–1.7 units log for P. aeruginosa, E. coli, Enterococcus sp., C. perfringens, and for Staphylococcus sp., respectively. Although CO2 addition did not increase disinfection, it did significantly increase biomass productivity (by ≈60%) and settleability (by ≈350%). Additionally, even at the lower 5-day hydraulic retention time, CO2 addition improves removal of chemical oxygen demand (COD), total organic carbon (TOC), total organic nitrogen and phosphorus by 97, 91, 12 and 50%, respectively.

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