scholarly journals Viability of a Single-Stage Unsaturated-Saturated Granular Activated Carbon Biofilter for Greywater Treatment

2020 ◽  
Vol 12 (21) ◽  
pp. 8847
Author(s):  
Ahmed Sharaf ◽  
Bing Guo ◽  
David C. Shoults ◽  
Nicholas J. Ashbolt ◽  
Yang Liu
Keyword(s):  
Activated Carbon ◽  
Removal Rate ◽  
Feeding Strategy ◽  
Oxygen Demand ◽  
Granular Activated Carbon ◽  
Complete Removal ◽  
Single Stage ◽  
Chemical Oxygen Demand Removal ◽  
Over Time ◽  
Sewage Source

Compared with conventionally collected sewage, source-diverted greywater has a higher potential for on-site treatment and reuse due to its lower contaminant levels and large volume. A new design of granular activated carbon (GAC) biofilters was developed by incorporating unsaturated and saturated zones in a single stage to introduce an efficient, passive, and easy-to-operate technology for greywater on-site treatment at the household scale. The design was customized for its intended application considering various aspects including the reactor’s configuration, packing media, and feeding strategy. With the highest hydraulic and organic loadings of 1.2 m3 m−2 d−1 and 3.5 kg COD m−2 d−1, respectively, and the shortest retention time of 2.4 h, the system maintained an average total chemical oxygen demand removal rate of 94% with almost complete removal of nutrients throughout its 253 days of operation. The system showed a range of reduction efficacy towards five surrogates representing viruses, bacteria, and Cryptosporidium and Giardia (oo)cysts. A well-functioning biofilm was successfully developed, and its mass and activity increased over time with the highest values observed at the top layers. The key microbes within the biofilter were revealed. Feasibility of the proposed technology was investigated, and implications for design and operation were discussed.

scholarly journals Study on Chromaticity Removal from Mineral Processing Wastewater with Salicylic Hydroxamic Acid by Granular Activated Carbon Catalyzed Ozonation

Minerals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 359
Author(s):  
Liping Zhang ◽  
Shengnian Wu ◽  
Nan Zhang ◽  
Ruihan Yao ◽  
Eryong Wu
Keyword(s):  
Activated Carbon ◽  
Reaction Time ◽  
Hydroxamic Acid ◽  
Ph Value ◽  
Oxygen Demand ◽  
Granular Activated Carbon ◽  
Mineral Processing ◽  
Ultraviolet Absorption Spectrum ◽  
Experimental Conditions ◽  
Removal Ratio

Salicylic hydroxamic acid is a novel flotation reagent used in mineral processing. However, it impacts the flotation wastewater leaving behind high chromaticity which limits its reuse and affects discharge for mining enterprises. This study researched ozonation catalyzed by the granular activated carbon (GAC) method to treat the chromaticity of the simulated mineral processing wastewater with salicylic hydroxamic acid. The effects of pH value, ozone (O3) concentration, GAC dosage, and reaction time on chromaticity and chemical oxygen demand (CODCr) removal were discussed. The results of individual ozonation experiments showed that the chromaticity removal ratio reached 79% and the effluent chromaticity exceeded the requirement of reuse and discharge when the optimal experimental conditions were pH value 3, ozone concentration 6 mg/L, and reaction time 40 min. The orthogonal experimental results of catalytic ozonation with GAC on chromaticity removal explained that the chromaticity removal ratio could reach 96.36% and the chromaticity of effluent was only 20 when the optimal level of experimental parameters was pH value 2.87, O3 concentration 6 mg/L, GAC dosage 0.06 g/L, reaction time 60 min respectively. The degradation pathway of salicylic hydroxamic acid by ozonation was also considered based on an analysis with ultraviolet absorption spectrum and high-performance liquid chromatography (HPLC).

Pecan shell-based granular activated carbon for treatment of chemical oxygen demand (COD) in municipal wastewater

2004 ◽  
Vol 94 (2) ◽  
pp. 129-135 ◽  
Author(s):  
R.R. Bansode ◽  
J.N. Losso ◽  
W.E. Marshall ◽  
R.M. Rao ◽  
R.J. Portier
Keyword(s):  
Activated Carbon ◽  
Chemical Oxygen Demand ◽  
Municipal Wastewater ◽  
Oxygen Demand ◽  
Granular Activated Carbon

Successful treatment of high azo dye concentration wastewater using combined anaerobic/aerobic granular activated carbon-sequencing batch biofilm reactor (GAC-SBBR): simultaneous adsorption and biodegradation processes

2013 ◽  
Vol 67 (8) ◽  
pp. 1816-1821 ◽  
Author(s):  
E. Hosseini Koupaie ◽  
M. R. Alavi Moghaddam ◽  
S. H. Hashemi
Keyword(s):  
Activated Carbon ◽  
High Performance ◽  
Batch Reactor ◽  
Oxygen Demand ◽  
Microscopic Analysis ◽  
Granular Activated Carbon ◽  
Biofilm Reactor ◽  
Treatment System ◽  
Electron Microscopic ◽  
Sequencing Batch Biofilm Reactor

The application of a granular activated carbon-sequencing batch biofilm reactor (GAC-SBBR) for treatment of wastewater containing 1,000 mg/L Acid Red 18 (AR18) was investigated in this research. The treatment system consisted of a sequencing batch reactor equipped with moving GAC as biofilm support. Each treatment cycle consisted of two successive anaerobic (14 h) and aerobic (8 h) reaction phases. Removal of more than 91% chemical oxygen demand (COD) and 97% AR18 was achieved in this study. Investigation of dye decolorization kinetics showed that the dye removal was stimulated by the adsorption capacity of the GAC at the beginning of the anaerobic phase and then progressed following a first-order reaction. Based on COD analysis results, at least 77.8% of the dye total metabolites were mineralized during the applied treatment system. High-performance liquid chromatography analysis revealed that more than 97% of 1-naphthyalamine-4-sulfonate as one of the main sulfonated aromatic constituents of AR18 was removed during the aerobic reaction phase. According to the scanning electron microscopic analysis, the microbial biofilms grew in most cavities and pores of the GAC, but not on the external surfaces of the GAC.

Coupling of anodic oxidation and adsorption by granular activated carbon for chemical oxygen demand removal from 4,4′-diaminostilbene-2,2′-disulfonic acid wastewater

2010 ◽  
Vol 62 (11) ◽  
pp. 2669-2677 ◽  
Author(s):  
Lizhang Wang ◽  
Yuemin Zhao
Keyword(s):  
Activated Carbon ◽  
Chemical Oxygen Demand ◽  
Residence Time ◽  
Applied Voltage ◽  
Oxygen Demand ◽  
Granular Activated Carbon ◽  
Cod Removal ◽  
Disulfonic Acid ◽  
High Concentration ◽  
Solution Ph

Experiments were performed to reduce chemical oxygen demand (COD) from 4,4′-diaminostilbene-2,2′-disulfonic (DSD) acid manufacturing wastewater using electrochemical oxidation coupled with adsorption by granular activated carbon. The COD removal is affected by the residence time and applied voltage. When the residence time is increased, lower value of COD effluent could be obtained, however, the average current efficiency (ACE) decreased rapidly, and so does the applied voltage. In addition, aeration could effectively enhance COD removal efficiency and protect anodes from corrosion. Furthermore, the acidic condition is beneficial to the rapid decrease of COD and the values of pH effluent are independent of the initial solution pH. The optimization conditions obtained from these experiments are applied voltage of 4.8 V, residence time of 180 min and air–liquid ratio of 4.2 with the COD effluent of about 690 mg L−1. In these cases, the ACE and energy consumption are 388% and 4.144 kW h kg−1 COD, respectively. These perfect results from the experiments illustrate that the combined process is a considerable alternative for the treatment of industrial wastewater containing high concentration of organic pollutants and salinity.

Incidence of the Presence of Lead on the Elimination of Humic Substances

2016 ◽  
Vol 723 ◽  
pp. 645-649
Author(s):  
Saâdia Guergazi ◽  
Mohamed Mahdi Missaoui
Keyword(s):  
Activated Carbon ◽  
Humic Substances ◽  
Reaction Rate ◽  
Activated Carbons ◽  
Removal Rate ◽  
Granular Activated Carbon ◽  
Maximum Efficiency ◽  
Carbon Powder ◽  
Powder Activated Carbon ◽  
Agitation Time

The main objective of our work is to test the performance of powder activated carbon (PAC) and granular activated carbon (GAC) in the retention of humic substances in the presence of lead. The adsorption tests conducted in synthetic solutions of distilled water. The results showed that, the removal efficiency of humic substances varies with the agitation time was obtained maximum efficiency after 180 minutes for PAC and 300 for the GAC. However, on granular activated carbon (GAC) recorded an improvement in the removal of humic substances in the order of 1.60%. The reaction rate is the same for the activated carbon powder (PAC). By against, for the GAC the removal rate of humic substances in the presence of lead is slower. A comparison between our results with the absorption of humic substances without the presence of lead showed that the elimination of humic substances (10 mg/l) in the presence of lead (5mg/l) on powder activated carbon (1 g/L) is disturbed. The removal efficiencies decrease with the increase on the pH of medium in an interval ranging from 2 to 12.The variation of the mass of lead has recorded an inhibiting role in the adsorption of humic substances for both activated carbons.

scholarly journals Chemical-Free Greywater Treatment Using Aeration, Sedimentation, Followed by Granular Activated Carbon Filter (GAC) -A Case Study of Baghdad city household

2020 ◽  
Vol 26 (10) ◽  
pp. 66-79
Author(s):  
Marwa M. Ali ◽  
Nawar Omran Ali ◽  
Mahdi Shanshal Jaafar
Keyword(s):  
Activated Carbon ◽  
Removal Efficiency ◽  
Irrigation Treatment ◽  
Treatment Plant ◽  
Oxygen Demand ◽  
Granular Activated Carbon ◽  
Water Source ◽  
Small Scale ◽  
Activated Carbon Filter ◽  
Carbon Filter

Greywater is a possible water source that can be improved for meeting the quality required for irrigation. Treatment of greywater can range from uncomplicated coarse filtration to advanced biological treatment. This article presents a simple design of a small scale greywater treatment plant, which is a series of physical and natural processes including screening, aeration, sedimentation, and filtration using granular activated carbon filter and differentiates its performance with sand filter. The performance of these units with the dual filter media of (activated carbon with sand) in treatment of greywater from Iraqi house in Baghdad city during 2019 and that collected from several points including washbasins, kitchen sink, bathrooms, and laundry, was recorded in terms of removal efficiency of particular pollutants like Turbidity 94%, chemical oxygen demand (COD) 93%, and oil 91%. Dual filter was the most effective filter for decreasing these pollutants, while sand indicates the lowest removal efficiency. In general, granular activated carbon media seemed to be the most proper medium to improve greywater quality for reaching the quality of irrigation within the terms of organic matter decrease. Accordingly, this technology may be reliable for greywater treatment in a residential area.

scholarly journals Application of composite degradable modified starch-based flocculant on dewatering and recycling properties

2020 ◽  
Vol 82 (10) ◽  
pp. 2051-2061
Author(s):  
Jianbo Liu ◽  
Shouhao Jia ◽  
Liming Xu ◽  
Feifei Zhu ◽  
Shan Ren ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Fermentation Process ◽  
Removal Rate ◽  
Oxygen Demand ◽  
Ammonia Nitrogen ◽  
Modified Starch ◽  
Chemical Oxygen Demand Removal ◽  
Sludge Dewatering ◽  
Capillary Suction ◽  
And Storage

Abstract Sludge dewatering is an important step for wastewater treatment. Composite degradable flocculant (CDF) was prepared by cationic polyacrylamide (PAM) grafting onto modified starch with a novel initiator, and characterized by Fourier transform infrared spectroscopy. The microstructure of flocculated sludge was characterized by scanning electron microscopy. The study investigated the properties of CDF compared to PAM, which showed that the prepared CDF exhibited a highly effective flocculation on sludge dewatering, a higher transmittance and chemical oxygen demand removal rate, and a lower value of effluent ammonia nitrogen and total phosphorus. The fermentation process was also analyzed by testing the performance of dewatered sludge (temperature, pH, ammonia nitrogen, E4/E6 (humic acid absorbance at 465 nm (E4) and 665 nm (E6))). The dehydrated sludge with CDF could be easily compressed into cakes by belt-filter for easy transportation and storage. With the continuous addition of CDF and PAM, the corresponding index of capillary suction time (CST) increased. Moreover, the total value of CST with CDF was low, showing a good dewaterability. In addition, the sludge index of pumping time and moisture content with CDF were low in contrast with PAM. Fermentation experiments demonstrated that sludge with CDF had a comparatively high temperature and low value of E4/E6. Such novel CDF shows enormous potential in wastewater treatment and sludge fermentation.

Anaerobic Treatment of Coal Gasification Wastewater

1987 ◽  
Vol 19 (1-2) ◽  
pp. 229-236 ◽  
Author(s):  
Makram T. Suidan ◽  
Peter Fox ◽  
John T. Pfeffer
Keyword(s):  
Activated Carbon ◽  
Coal Gasification ◽  
Physical Adsorption ◽  
Oxygen Demand ◽  
Granular Activated Carbon ◽  
Anaerobic Treatment ◽  
Partial Replacement ◽  
Anaerobic Culture ◽  
Second Stage ◽  
Coal Gasification Wastewater

A sequence of unit processes consisting of a berl-saddle-packed anaerobic filter, an expanded-bed, granular activated carbon anaerobic reactor and an activated sludge nitrification system was employed for the treatment of synthetically prepared coal gasification wastewater. After acclimation, the coal gasification wastewater was fed to the treatment process train at three different chemical oxygen demand levels; these were 1,513. 3,027, and 7,567 mg/ℓ, respectively. No biological activity was observed in the first-stage filter, while excellent removal of organic matter was achieved in the second and third stages of the treatment systems. However, toxicity to the anaerobic culture in the second-stage reactor was observed during the second and third loading levels. This toxicity was overcome by employing a partial replacement schedule of the granular activated carbon medium in the reactor. This study represents an example of how biodegradation and physical adsorption may be successfully combined during the treatment of wastewaters containing toxic or inhibitory substances.

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