Effects of Hydraulic Retention Time and Solid Retention Time of POME on COD Removal Efficiency

A 4 L submerged tubular ceramic membrane bioreactor (MBR) was applied in laboratory scale to treat 2,400 mg-COD/L high strength wastewater. A prolonged sludge retention time (SRT) of 200 day, in contrast to the conventional SRT of 5 to 15 days, was explored in this study, aiming to reduce substantially the amount of disposed sludge. The MBR system was operated for a period of 142 days in four runs, differentiated by specific oxygen utilization rate (SOUR) and hydraulic retention time (HRT). It was found that the MBR system produced more than 99% of suspended solid reduction. Mixed liquor suspended solids (MLSS) was found to be adversely proportional to HRT, and in general higher than the value from a conventional wastewater treatment plant. A chemical oxygen demand (COD) removal efficiency was achieved as high as 98% in Run 1, when SOUR was in the range of 100-200 mg-O/g-MLVSS/hr. Unexpectedly, the COD removal efficiency in Run 2 to 4 was higher than 92%, on average, where higher HRT and abnormally low SOUR of 20-30 mg-O/g-MLVSS/hr prevailed. It was noted that the ceramic membrane presented a significant soluble nutrient rejection when the microbial metabolism of biological treatment broke down.

Download Full-text

PENGHILANGAN POLUTAN ORGANIK DAN PADATAN TERRSUSPENSI DI DALAM AIR LIMBAH DOMESTIK DENGAN PROSES MOVING BED BIOFILM REACTOR (MBBR)

Jurnal Air Indonesia ◽

10.29122/jai.v8i1.2382 ◽

2018 ◽

Vol 8 (1) ◽

Author(s):

Nusa Idaman Said ◽

Teguh Iman Santoso

Keyword(s):

Wastewater Treatment ◽

Removal Efficiency ◽

Retention Time ◽

Domestic Wastewater ◽

Biofilm Reactor ◽

Cod Removal ◽

Aeration Tank ◽

Moving Bed Biofilm Reactor ◽

Moving Bed ◽

Cod Removal Efficiency

One of the alternative technologies that could be used for domestic waste water treatment is the Moving Bed Biofilm Reactor (MBBR). MBBR in principle is activated sludge that is increased by adding media in to the reactor, so there are two treatments process happened inside, suspended growth and attached growth. This research is using bioball as a media which has surface area of ±210 m2/m3 by 20% volume of reactor volume. Wastewater treatment by MBBR uses variations of Hydraulic Retention time (HRT) 12, 8, 6, and 4 hours, then the parameters measured were BOD, COD, TSS, temperature, and pH. Result of the study shows that within HRT for 12 hours in aeration tank, removal efficiency of COD is 81,37%, BOD is 82,4%, and TSS is 90,05%. HRT for 8 hours, COD removal efficiency is 88,72%, BOD is 89,7%, and TSS is 92,06%. HRT for 6 hours, COD removal efficiency is 85,48%, BOD is 80,15%, and TSS is 94,85%. HRT for 4 hours, COD removal efficiency is 81,07%, BOD is 87,88%, and TSS is 94,86%. With a retention time of 4 hours, the effluent results domestic wastewater treatment using MBBR has met quality standards in accordance with KEPMEN LH no. 112 of 2003 on Domestic Wastewater Quality Standard and Jakarta Governor Regulation no. 122 of 2005 on Domestic Wastewater Management in Special Province of Jakarta. Keywords: Domestic wastewater, MBBR, bioball.

Download Full-text

Optimization of Biogas Production from Dairy Wastewater using Upflow Anaerobic Filter (UAF) Reactor

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.d7447.049420 ◽

2020 ◽

Vol 9 (4) ◽

pp. 1469-1472

Keyword(s):

Wastewater Treatment ◽

Removal Efficiency ◽

Hydraulic Retention Time ◽

Loading Rate ◽

Biogas Production ◽

Cod Removal ◽

Dairy Wastewater ◽

Organic Loading Rate ◽

Anaerobic Filter ◽

Cod Removal Efficiency

The present study explores the feasibility of biogas production from dairy wastewater in the UAF reactor with simultaneous wastewater treatment. The study was carried out at different hydraulic retention times (8h, 12h, 16h, 24h). Two different media such as pebble stone media and aggregate media were used as the packed media. The maximum COD removal efficiency of 91.55 % is achieved at the hydraulic retention time of 24 Hours with an organic loading rate of 1.35 kg/m3 /d for aggregate media, whereas for pebble stone media a maximum COD removal efficiency of 76.32 % is achieved. Before the start of the experiments, the COD/BOD ratio is fixed to 1.4 with initial COD and BOD of 1350 mg/L and 960 mg/L. So, from the results it is concluded that the Upflow Anaerobic Filter (UAF) Reactor can be used as a one of the best treatment methods for the diary wastewater treatment.

Download Full-text

Evaluation of a tropical single-cell waste stabilization pond system for irrigation

Water Science & Technology ◽

10.2166/wst.1995.0495 ◽

1995 ◽

Vol 31 (12) ◽

pp. 267-273 ◽

Cited By ~ 4

Author(s):

B. S. O. Ceballos ◽

A. Konig ◽

B. Lomans ◽

A. B. Athayde ◽

H. W. Pearson

Keyword(s):

Single Cell ◽

Removal Efficiency ◽

Retention Time ◽

Hydraulic Retention Time ◽

Full Scale ◽

Waste Stabilization Pond ◽

North East ◽

Helminth Eggs ◽

Waste Stabilization ◽

Better Than

A single full-scale primary facultative pond in Sapé, north-east Brazil was monitored for performance and efficiency. The pond had a hydraulic retention time of 61 days and achieved a 95% BOD5 removal efficiency and had no helminth eggs in the effluent. The effluent failed to meet the WHO faecal coliform guideline for unrestricted irrigation. The pond was dominated by the cyanobacterium Microcystis and gave better than predicted orthophosphate removal. Details of how the system could be simply upgraded utilizing the same land are discussed.

Download Full-text

Investigation of Heavy Metal Effects on the Anaerobic Co-Digestion Process of Waste Activated Sludge and Septic Tank Sludge

International Journal of Chemical Engineering ◽

10.1155/2019/5138060 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9

Author(s):

Quang-Minh Nguyen ◽

Duy-Cam Bui ◽

Thao Phuong ◽

Van-Huong Doan ◽

Thi-Nham Nguyen ◽

...

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Activated Sludge ◽

Removal Efficiency ◽

Biogas Production ◽

Cod Removal ◽

Septic Tank ◽

Waste Activated Sludge ◽

Digestion Process ◽

Cod Removal Efficiency

The effect of copper, zinc, chromium, and lead on the anaerobic co-digestion of waste activated sludge and septic tank sludge in Hanoi was studied in the fermentation tests by investigating the substrate degradation, biogas production, and process stability at the mesophilic fermentation. The tested heavy metals were in a range of concentrations between 19 and 80 ppm. After the anaerobic tests, the TS, VS, and COD removal efficiency was 4.12%, 9.01%, and 23.78% for the Cu(II) added sample. Similarly, the efficiencies of the Zn(II) sample were 1.71%, 13.87%, and 16.1% and Cr(VI) efficiencies were 15.28%, 6.6%, and 18.65%, while the TS, VS, and COD removal efficiency of the Pb(II) added sample was recorded at 16.1%, 17.66%, and 16.03% at the concentration of 80 ppm, respectively. Therefore, the biogas yield also decreased by 36.33%, 31.64%, 31.64%, and 30.60% for Cu(II), Zn(II), Cr(VI), and Pb(II) at the concentration of 80 ppm, compared to the raw sample, respectively. These results indicated that Cu(II) had more inhibiting effect on the anaerobic digestion of the sludge mixture than Zn(II), Cr(VI), and Pb(II). The relative toxicity of these heavy metals to the co-digestion process was as follows: Cu (the most toxic) > Zn > Cr > Pb (the least toxic). The anaerobic co-digestion process was inhibited at high heavy metal concentration, which resulted in decreased removal of organic substances and produced biogas.

Download Full-text

Combined treatment of hydroxypropyl guar gum in oilfield fracturing wastewater by coagulation and the UV/H2O2/ferrioxalate complexes process

Water Science & Technology ◽

10.2166/wst.2017.552 ◽

2017 ◽

Vol 77 (3) ◽

pp. 565-575 ◽

Cited By ~ 3

Author(s):

Zhenchao Zhang

Keyword(s):

Removal Efficiency ◽

Guar Gum ◽

Combined Treatment ◽

Cod Removal ◽

Treated Wastewater ◽

Spectra Analysis ◽

Hydroxypropyl Guar ◽

Coagulation Process ◽

Cod Removal Efficiency ◽

Hydroxypropyl Guar Gum

Abstract Hydroxypropyl guar gum is considered to be a main component of oilfield fracturing wastewater (OFW). This work is intended to optimize the experimental conditions for the maximum oxidative degradation of hydroxypropyl guar gum by the coagulation and UV/H2O2/ferrioxalate complexes process. Optimal reaction conditions were proposed based on the chemical oxygen demand (COD) removal efficiency and UV_vis spectra analysis. The overall removal efficiency of COD reached 83.8% for a dilution ratio of raw wastewater of 1:2, pH of 4 and FeCl3 loading of 1,000 mg/L in the coagulation process; the dosage of H2O2 (30%,v/v) was 0.6% (v/v) and added in three steps, the n(H2O2)/n(Fe2+) was 2:1, n(Fe2+)/n(C2O42−) was 3:1 and pH was 4 in the UV/H2O2/ferrioxalate complexes process; pH was adjusted to 8.5–9 by NaOH and then cationic polyacrylamide (CPAM) of 2 mg/L was added in the neutralization and flocculation process. The decrease in COD during the coagulation process reduced the required H2O2 dosage and improved efficiency in the subsequent UV/H2O2/ferrioxalate complexes process. Furthermore, COD removal efficiency significantly increased by more than 13.4% with the introduction of oxalate compared with UV/Fenton. The UV_vis spectra analysis results indicated that the coagulation and UV/H2O2/ferrioxalate complexes process could efficiently remove the hydroxypropyl guar gum dissolved in OFW. An optimal combination of these parameters produced treated wastewater that met the GB8978-1996 Integrated Wastewater Discharge Standard level III emission standard.

Download Full-text

Textile Wastewater Treatment Using Combined Process of Biological Wriggle Bed and Ozone Biological Aerated Filter

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.441.589 ◽

2012 ◽

Vol 441 ◽

pp. 589-592

Author(s):

Zhi Min Fu ◽

Yu Gao Zhang ◽

Xiao Jun Wang

Keyword(s):

Wastewater Treatment ◽

Removal Efficiency ◽

Textile Wastewater ◽

Cod Removal ◽

Biological Aerated Filter ◽

Combined Process ◽

Cod Removal Efficiency ◽

Aerated Filter ◽

Textile Wastewater Treatment

A combined process of biological wriggle bed and ozone biological aerated filter was utilized to treat textile wastewater. Results showed that COD removal efficiency was almost 90.4%. The average effluent COD was 85.87 mg/L. The effluent colority was 64-32 times. This study indicated that the combined process is potentially useful for treating textile wastewater.

Download Full-text

Electrocoagulation and nanofiltration integrated process application in purification of bilge water using response surface methodology

Water Science & Technology ◽

10.2166/wst.2016.168 ◽

2016 ◽

Vol 74 (3) ◽

pp. 564-579 ◽

Cited By ~ 11

Author(s):

Ceyhun Akarsu ◽

Yasin Ozay ◽

Nadir Dizge ◽

H. Elif Gulsen ◽

Hasan Ates ◽

...

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Removal Efficiency ◽

Cod Removal ◽

Positive Sign ◽

Aluminum Electrode ◽

Integrated Process ◽

Bilge Water ◽

Cod Removal Efficiency ◽

Initial Ph

Marine pollution has been considered an increasing problem because of the increase in sea transportation day by day. Therefore, a large volume of bilge water which contains petroleum, oil and hydrocarbons in high concentrations is generated from all types of ships. In this study, treatment of bilge water by electrocoagulation/electroflotation and nanofiltration integrated process is investigated as a function of voltage, time, and initial pH with aluminum electrode as both anode and cathode. Moreover, a commercial NF270 flat-sheet membrane was also used for further purification. Box–Behnken design combined with response surface methodology was used to study the response pattern and determine the optimum conditions for maximum chemical oxygen demand (COD) removal and minimum metal ion contents of bilge water. Three independent variables, namely voltage (5–15 V), initial pH (4.5–8.0) and time (30–90 min) were transformed to coded values. The COD removal percent, UV absorbance at 254 nm, pH value (after treatment), and concentration of metal ions (Ti, As, Cu, Cr, Zn, Sr, Mo) were obtained as responses. Analysis of variance results showed that all the models were significant except for Zn (P > 0.05), because the calculated F values for these models were less than the critical F value for the considered probability (P = 0.05). The obtained R2 and Radj2 values signified the correlation between the experimental data and predicted responses: except for the model of Zn concentration after treatment, the high R2 values showed the goodness of fit of the model. While the increase in the applied voltage showed negative effects, the increases in time and pH showed a positive effect on COD removal efficiency; also the most effective linear term was found as time. A positive sign of the interactive coefficients of the voltage–time and pH–time systems indicated synergistic effect on COD removal efficiency, whereas interaction between voltage and pH showed an antagonistic effect.

Download Full-text

Impact of Precipitants on the Structure and Properties of Fe-Co-Ce Composite Catalysts

Journal of Nanomaterials ◽

10.1155/2016/3797896 ◽

2016 ◽

Vol 2016 ◽

pp. 1-8

Author(s):

Yongli Zhang ◽

Shujuan Dai ◽

Yanbo Zhou ◽

Kai Lin

Keyword(s):

Particle Size ◽

Methyl Orange ◽

Removal Efficiency ◽

Cod Removal ◽

Catalytic Wet Air Oxidation ◽

Structure And Properties ◽

Air Oxidation ◽

Wet Air Oxidation ◽

Composite Catalysts ◽

Cod Removal Efficiency

Fe-Co-Ce composite catalysts were prepared by coprecipitation method using CO(NH2)2, NaOH, NH4HCO3, and NH3·H2O as precipitant agents. The effects of the precipitant agents on the physicochemical properties of the Fe-Co-Ce based catalysts were investigated by SEM, TEM, BET, TG-DTA, and XRD. It was found that the precipitant agents remarkably influenced the morphology and particle size of the catalysts and affected the COD removal efficiency, decolorization rate, and pH of methyl orange for catalytic wet air oxidation (CWAO). The specific surface area of the Fe-Co-Ce composite catalysts successively decreased in the order of NH3·H2O, NH4HCO3, NaOH, and CO(NH2)2, which correlated to an increasing particle size that increased for each catalyst. For the CWAO of a methyl orange aqueous solutions, the effects of precipitant agents NH3·H2O and NaOH were superior to those of CO(NH2)2and NH4HCO3. The catalyst prepared using NH3·H2O as the precipitant agent was mostly composed of Fe2O3, CoO, and CeO2. The COD removal efficiency of methyl orange aqueous solution for NH3·H2O reached 92.9% in the catalytic wet air oxidation. Such a catalytic property was maintained for six runs.

Download Full-text

Development of a two-stage flexible fibre biofilm reactor for treatment of food processing wastewater

Water Science & Technology ◽

10.2166/wst.2003.0604 ◽

2003 ◽

Vol 47 (11) ◽

pp. 189-194 ◽

Cited By ~ 6

Author(s):

Q.J. Yu ◽

H. Xu ◽

D. Yao ◽

P. Williams

Keyword(s):

Removal Efficiency ◽

Food Processing ◽

Cost Effective ◽

Biofilm Reactor ◽

Cod Removal ◽

Two Stage ◽

Cod Removal Efficiency ◽

Cost Effective Treatment ◽

Removal Efficiencies ◽

Food Processing Wastewater

Biofilm (or attached growth) reactors can be effectively used to treat organic wastewater from various industries such as food processing industry. They have a number of advantages including high organic loading rates (OLRs) and improved operational stability. A flexible fibre biofim reactor (FFBR) has been developed for efficient and cost effective treatment of food processing wastewater. In the process, simple flexible fibre packing with a very high specific surface area is used as support for microorganisms. The COD removal efficiencies for a range of OLRs have been studied. The FFBR can support an increasingly high OLR, but with a corresponding decrease in the COD removal efficiency. Therefore, a two-stage FFBR was developed to increase the treatment efficiency for systems with high OLRs. Experimental results indicated that a high overall COD removal efficiency could be achieved. At an influent COD of about 2700 mg/L and an OLR of 7.7 kgCOD/m3d, COD removal efficiencies of 76% and 82% were achieved in the first and the second stage of the reactor, respectively. The overall COD removal efficiency was 96%. Therefore, even for wastewater samples with high organic strength, high quality treated effluents could be readily achieved by the use of multiple stage FFBRs.

Download Full-text