The anaerobic and starving treatment eliminates filamentous bulking and recovers biocathode biocatalytic activity with residual organic loading in microbial electrochemical system

The membrane fouling behaviors and fouling mechanism of filamentous bulking sludge in membrane bioreactor (MBR) have been reported in recent studies. However, few studies have been conducted towards the causes and control of filamentous bulking sludge in MBR. In order to make clear the conditions of filamentous bacteria overgrowth in MBR, the impact of DO and organic loading rate on filamentous growth and its characteristics were investigated in this paper. The results showed that overgrowth of filamentous bacteria occurred under a relatively high substrate concentration (organic loading rate was 0.61 KgCOD/(KgMLSS•d), and DO was above 2 mg/L) in MBR. Nutrient removal effect can not be deteriorated under filamentous bulking sludge, with average 95, 57 and 92% removal efficiencies of COD, TN and TP respectively. The particle size of filamentous sludge was larger than that of normal sludge and the filamentous bacteria produced more SMP and EPS than floc forming bacteria.

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RESEARCH AND EVALUATE TREATMENT EFFICIENCY ON TAPIOCA PROCESSING INDUSTRIAL WASTEWATER BY AEROBIC BIOFILTER TECHNOLOGY WITH VARIOUS MATERIALS

Science and Technology Development Journal ◽

10.32508/stdj.v13i3.2143 ◽

2010 ◽

Vol 13 (3) ◽

pp. 54-66

Author(s):

Phuong Thi Thanh Nguyen ◽

Phuoc Van Nguyen ◽

Anh Cam Thieu

Keyword(s):

Wastewater Treatment ◽

Industrial Wastewater ◽

Utilization Rate ◽

Organic Loading ◽

Treatment Efficiency ◽

Research Results ◽

Loading Rates

This study was performed to evaluate the efficiency of tapioca processing wastewater treatment using aerobic biofilter with variety of biofilter media: coir, coal, PVC plastic and Bio - Ball BB15 plastic. Research results in the lab demonstrated all four aerobic biofilter models processed can treated completely N and COD which COD reached 90-98% and N reached 61-92%, respectively, at the organic loading rates in range of 0.5, 1, 1.5 and 2 kgCOD/m3.day. The results identified coir filter was the best in four researched materials with removal COD and specific substract utilization rate can reach 98%, and 0.6 kg COD/kgVSS.day. Research results open the new prospects for the application of the cheap materials, available for wastewater treatment.

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APLIKASI PROSES DIGESTASI ANAEROBIK LUMPUR BIOLOGI INSTALASI PENGOLAHAN AIR LIMBAH INDUSTRI KERTAS

JURNAL SELULOSA ◽

10.25269/jsel.v4i02.64 ◽

2014 ◽

Vol 4 (02) ◽

Author(s):

Rina S. Soetopo ◽

Sri Purwati ◽

Henggar Hardiani ◽

Mukharomah Nur Aini ◽

Krisna Adhitya Wardhana

Keyword(s):

Oxygen Demand ◽

Total Solid ◽

Pilot Scale ◽

Organic Content ◽

Solid Content ◽

Uasb Reactor ◽

Anaerobic Sludge ◽

Organic Loading ◽

Total Solid Content ◽

Average Value

A continuous pilot scale study has been conducted to investigate the effectiveness of anaerobic digestion of biological sludge. The sludge has a total solid content of 0.53% - 1.1%, pH of 7.20 to 7.32. Its organic content is about 97 %, The research were conducted in two stages, which are acidification (performed in 3 m3 the Continously Stirred Tank Reactor/CSTR at pH of 5.5 to 6.0) and methanation (performed in 5 m3 the Up Flow Anaerobic Sludge Blanket/UASB reactor at pH 6.5 to 7.0). The retention time (RT) was gradually shortened from 6 days to 1 day for acidification and from 8 days to 2 days for methanation. The results showed that operating the CSTR at the RT of 1 day and the organic loading of 8.23 g Volatile Solid (VS)/m3.day could produce Volatile Fatty Acid (VFA) at an average value of 17.3 g/kg VS.day. Operating the UASB reactor at the RT of 2 days and the organic loading (Chemical Oxygen Demand/COD) of 2.4 kg COD/m3.day could produce biogas at an average value of 66.3 L/day, with an average methane content of 69.9%, methane rate of 0.17 L CH4/g COD reduction or 19.06 L CH4/kg VS. Furthermore, methanation could reduce COD at an average value of 51.2 %, resulting in the effluent average value of COD filtrate and COD total of 210.1 mg/L and 375.2 mg /L, respectively.Keywords: acidification, methanation, CSTR, UASB, biogas ABSTRAKPercobaan digestasi anaerobik lumpur IPAL biologi industri kertas secara kontinyu skala pilot telah dilakukan di industri kertas dengan tujuan mengkaji efektivitas proses digestasi anaerobik dalam mengolah lumpur tersebut. Lumpur yang digunakan memiliki total solids sekitar 0,53% – 1,1%, pH netral (7,20 – 7,32) dengan komponen utama senyawa organik sekitar 97%. Percobaan dilakukan dalam dua tahap yaitu asidifikasi dalam reaktor CSTR berkapasitas 3 m3 pada pH 5,5 – 6,0 dan metanasi dalam reaktor UASB berkapasitas 5 m3 pada pH 6,5 – 7,0. Percobaan dilakukan dengan waktu retensi yang dipersingkat secara bertahap dari 6 hari ke 1 hari untuk proses asidifikasi dan dari 8 hari ke 2 hari untuk proses metanasi. Hasil percobaan menunjukkan bahwa pengoperasian reaktor CSTR dengan waktu retensi 1 hari dan beban organik 8,3 g VS/m3.hari dapat menghasilkan VFA rata-rata 17,3 g/kg VS.hari dengan kisaran 8,36 – 30,59 g/kg VS.hari, sedangkan pengoperasian reaktor UASB pada waktu retensi 2 hari dan beban organik 2,4 kg COD/m3.hari dapat menghasilkan biogas rata-rata 66,3 L/hari dengan kadar metana rata-rata 69,9% atau 0,17 L CH4/g COD reduksi atau 19,06 L CH4/kg VS. Selain itu proses metanasi dapat menurunkan COD terlarut rata-rata 51,2%, dengan konsentrasi efluen COD terlarut rata-rata 210,1 mg/L dan COD total rata-rata 375,2 mg/L.Kata kunci: asidifikasi, metanasi, CSTR, UASB, biogas

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Variation in Sludge Settleability with Temperature

Water Quality Research Journal ◽

10.2166/wqrj.1980.005 ◽

1980 ◽

Vol 15 (1) ◽

pp. 73-82 ◽

Cited By ~ 1

Author(s):

J.G. Henry ◽

E.E. Salenieks

Keyword(s):

Activated Sludge ◽

Effect Of Temperature ◽

Organic Load ◽

Limiting Factor ◽

Appreciable Effect ◽

Loading Rates ◽

Bench Scale ◽

Filamentous Bulking ◽

Filamentous Microorganisms ◽

Sludge Settleability

Abstract This study examined the effect of temperature on the settleabi1ity of activated sludge at various organic loading rates. Five completely mixed, bench-scale, activated sludge plants, operating under similar conditions at 5, 10 and 19°C, were continuously fed diluted, settled sewage supplemented with carbohydrate (sucrose). Hydraulic loading rates, MLSS and pH were maintained at constant levels during the experiments to eliminate these factors are variables. Dissolved oxygen was kept in excess of 3 mg/1 so that it would not be a limiting factor. Sludge Volume Indices (SVI ) and zone settling velocities were used to indicate changes in sludge settleability. Microscopic examination of the activated sludge indicated significant differences in the morphological features of filamentous microorganisms present at the two temperature extremes. At 19°C, the predominant forms were characterized by long curving trichomes, occasionally falsely branching, containing short cylindrical cells. At 5 °C, much smaller straight filaments, composed of long, narrow, rod-shaped cells appeared to be the principal microorganisms responsible for bulking. Various other filamentous forms were always present at each of the temperatures studied. Stirred sludge settling tests of moderately bulking sludges generally exhibited much higher settling velocities and lower SVI's than unstirred bulking samples. However, extremely filamentous bulking sludge exhibited comparable stirred and unstirred settling velocity and SVI values. The standard SVI test was found to be an inadequate indicator of the extent of bulking when trying to correlate the SVI failures from bench-scale performance with the results from continuous units. Lower temperature had no appreciable effect on COD removal efficiency as long as bulking did not cause a loss of solids in the effluent. However, results suggested that less than half the organic load could be accepted at 5°C, that could be handled at 19°C, before filamentous bulking occurred. A plot of loading versus temperature for various SVI's provided a visual indication of the safe loading limit below which bulking was unlikely to occur. The study clearly demonstrated that temperature can have a significant effect on sludge settleability.

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Control of Bulking in an Extended Aeration Sewage Treatment Plant

Water Quality Research Journal ◽

10.2166/wqrj.1972.004 ◽

1972 ◽

Vol 7 (1) ◽

pp. 13-20

Author(s):

D.D.P. Cane ◽

G.J. Farguhar

Keyword(s):

Dissolved Oxygen ◽

Control Measure ◽

Sewage Treatment ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

Effective Control ◽

Organic Loading Rate ◽

Organic Loading ◽

Mixed Liquor ◽

Air Supply

Abstract A case of filamentous activated sludge bulking was investigated at an extended aeration plant treating wastes from a highway service centre. The purpose of the study was to find an effective control measure for the bulking and, if possible, to determine the cause of the bulking condition. Experiments were conducted to determine the effects upon bulking of: (a) a controlled copper dosage to the mixed liquor, (b) variations in the organic loading rate, and (c) maintenance of high and low dissolved oxygen concentrations in the mixed liquor. The microorganism responsible for the bulking condition was tentatively identified as Sphaerotilus natans. Extensive growths of these bacteria occurred in the sludge when the mixed liquor dissolved oxygen concentration dropped below 0.5 mg/1. Such dissolved oxygen levels had frequently occurred at this plant due to the use of timed aeration cycles and the use of insufficient air supply during peak loading periods. Variations in organic loading rates were found to have no adverse effect on sludge settleability. When bulking was slight, the condition could be improved by increasing the dissolved oxygen level to 1.5 mg/1, or more. The rate at which the filamentous growths could be eliminated from a highly filamentous sludge by increased aeration was very slow, but could be greatly increased by the simultaneous feeding of copper to the mixed liquor at a dosage rate of 1.0 mg/1, based on the raw sewage flows.

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Stabilization of Organic Carbon and Nitrogen in Consolidating Benthal Deposits

Water Science & Technology ◽

10.2166/wst.1985.0191 ◽

1985 ◽

Vol 17 (6-7) ◽

pp. 929-940 ◽

Cited By ~ 1

Author(s):

C. W. Bryant ◽

L. G. Rich

Keyword(s):

Organic Carbon ◽

Model Verification ◽

Volatile Acid ◽

Free Energies ◽

Organic Loading ◽

Carbon And Nitrogen ◽

Loading Rates ◽

Degradation Reactions ◽

The Individual ◽

Organic Deposits

The objective of this research was to develop and validate a predictive model of the benthal stabilization of organic carbon and nitrogen in deposits of waste activated sludge solids formed at the bottom of an aerated water column, under conditions of continual deposition. A benthal model was developed from a one-dimensional, generalized transport equation and a set of first-order biological reactions. For model verification, depth profiles of the major interstitial carbon and nitrogen components were measured from a set of deposits formed in the laboratory at 20°C and a controlled loading rate. The observed sequence of volatile acid utilization in each benthal deposit was that which would be predicted by the Gibbs free energies of the individual degradation reactions and would be controlled by the reduction in interstitial hydrogen partial pressure with time. Biodegradable solids were solubilized rapidly during the first three weeks of benthal retention, but subsequent solubilization occurred much more slowly. The benthal simulation effectively predicted the dynamics of consolidating, organic deposits. Simulation of organic loading rates up to 250 g BVSS/(m2 day) indicated that the stabilization capacity of benthal deposits was far above the range of organic loading rates currently used in lagoon design.

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A Batch Activated Sludge Study of Pineapple Wastewater Using a Bioaugmentation Process

Water Science & Technology ◽

10.2166/wst.1991.0129 ◽

1991 ◽

Vol 24 (5) ◽

pp. 233-240 ◽

Cited By ~ 3

Author(s):

Nik Fuaad Nik Abllah ◽

Aik Heng Lee

Keyword(s):

Activated Sludge ◽

Removal Efficiency ◽

Treatment Plant ◽

Domestic Wastewater ◽

Ammonia Nitrogen ◽

Batch Reactors ◽

Organic Loading ◽

Suitable Alternative ◽

Organic Removal ◽

Sludge Production

A laboratory study was conducted to determine the feasibility of batch activated sludge reactor for treating pineapple wastewater and to examine the effects of bioaugmentation on treatment performance. The experimental set-up consists of eleven batch reactors. Activated sludge obtained from a wastewater treatment plant treating domestic wastewater was used as seed for the reactors. Synthetic pineapple wastewater was used as feed for the reactors. The eleven reactors were arranged to evaluate the total organic removal, nitrification, and sludge production by bioaugmentation process. Three major factors considered were influent organic loading, ammonia-nitrogen, and dosage of bacterial-culture-product addition. Removal of TOG (total organic carbon), sludge production in terms of SS(suspended solids), and ammonia-nitrogen removal variation are used as evaluation parameters. The TOC removal efficiency after the end of a 48 hour reactor run, for influent TOC of 350.14 to 363.30 mg/l, and 145.92 to 169.66 mg/l, was 94.41 to 95.89%, and 93.72 to 94.73% respectively. Higher organic removal was observed in the bioaugmented reactors with higher organic loading. The better organic removal efficiency in the bioaugmented reactors was probably due to activities of bacteria added. The test results also indicated that sludge yield was enhanced by the bacteria additive and high bacteria dosage produced less sludge. Bioaugmentation was observed to be a suitable alternative for enhancing the biological treatment of pineapple wastewater.

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TREATABILITY OF 2,4-D PRODUCTION WASTEWATERS

Water Science & Technology ◽

10.2166/wst.1994.0067 ◽

1994 ◽

Vol 30 (3) ◽

pp. 73-78 ◽

Cited By ~ 3

Author(s):

O. Tünay ◽

S. Erden ◽

D. Orhon ◽

I. Kabdasli

Keyword(s):

Hydrogen Peroxide ◽

Activated Sludge ◽

Partial Oxidation ◽

Chloride Concentration ◽

Chemical Oxidation ◽

Cod Removal ◽

Optimum Conditions ◽

Organic Loading ◽

Activated Sludge System ◽

Biological Treatability

This study evaluates the characterization and treatability of 2,4-D production wastewaters. Wastewaters contain 20000-40000 mg/l COD, 17000-30000 mg/l chloride and pH is around 1.0. Chemical oxidation with hydrogen peroxide provided almost complete COD removal. The optimum conditions are 3:1 H2O2/COD oxidant dosage, 3000 mg/l Fe3+ as catalyst and pH 3. Partial oxidation at 0.5:1 H2O2//COD ratio is also effective providing 67% COD removal. A batch activated sludge system is used for biological treatability. Dilution is needed to maintain a tolerable chloride concentration which increases through COD removal. pH also increased during COD removal. 85% COD removal is obtained for the 50% dilution at an organic loading of 0.3 day‒1 on a COD basis. Completely and partially oxidized wastewaters are also treated in the activated sludge down to 30 mg/l BOD5.

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Management of toxicity effects in a large wastewater treatment plant

Water Science & Technology ◽

10.2166/wst.1997.0469 ◽

1997 ◽

Vol 36 (2-3) ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

P. Grau ◽

B. P. Da-Rin

Keyword(s):

Wastewater Treatment ◽

Activated Sludge ◽

Wastewater Treatment Plant ◽

Treatment Plant ◽

Severe Case ◽

Treatment Efficiency ◽

Filamentous Bulking ◽

Biological Phenomena ◽

Inhibition Of Nitrification ◽

Toxicity Effects

An unusually severe case of toxicity accompanied by activated sludge filamentous bulking was observed at the wastewater treatment plant Sao Paulo-Barueri. Treatment efficiency of the plant, operated without major problems for more than five years before, was significantly hindered for almost six months. Occurrence of toxic shocks was confirmed partly directly but mostly indirectly by inhibition of nitrification and biological phenomena related to toxicity. Several measures adopted, including the recycled activated sludge chlorination, are described in the paper.

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