Internal circulation anaerobic digester—a upflow anaerobic sludge digester

Sewage source heat pump was integrated with internal circulation anaerobic digester (ICAD) to decrease the treatment cost of waste activated sludge. In the experiment, mesophilic digestion in ICAD was combined with thermal treatment at 60 °C with hydraulic retention time (HRT) of 1 day as pretreatment. The heat pump supplied heat recovering from the effluent of the wastewater treatment plant. The energy consumed by the heat pump was 39.2 and 48.6% less than the gas boiler and coal boiler respectively at a given amount of supplied heat. When the HRT of digestion was 10 days, the average total VSS removal and biogas yield rates of the system were 58.8% and 1.33 m3 · kgVSS−1 respectively. The integration of ICAD and sewage source heat pump offers a low-cost sludge treatment process with satisfactory organic removal.

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Effective Anaerobic Bio-Treatment of Fresh Leachate From Municipal Solid Waste Incineration Plant by Full-Scale Internal Circulation Reactor

Journal of Energy Resources Technology ◽

10.1115/1.4042085 ◽

2018 ◽

Vol 141 (4) ◽

Author(s):

Tao Wang ◽

Zhenxing Huang ◽

Hongyan Ren ◽

Hengfeng Miao ◽

Minxing Zhao ◽

...

Keyword(s):

Municipal Solid Waste ◽

Solid Waste ◽

Removal Efficiency ◽

Full Scale ◽

Cod Removal ◽

Anaerobic Sludge ◽

Internal Circulation ◽

Biogas Yield ◽

Cod Removal Efficiency ◽

Effluent Recirculation

This study aimed to investigate the effectiveness of the full-scale internal circulation (IC) reactor in biodegrading of municipal solid waste (MSW) fresh leachate under mesophilic conditions, where the anaerobic process stability, biogas yield, and sludge granulation were intensively investigated. The effects of operational parameters on the influent organic loading rate (OLR), chemical oxygen demand (COD) removal efficiency, alkalinity (ALK), pH, volatile fatty acids (VFAs) accumulation, and effluent recirculation were also studied. The results showed that the reactor operated stably and effectively. The COD removal efficiency and biogas yield could be maintained at (92.8 ± 2.0)% and (0.47 ± 0.05) m3/kg CODremoval, respectively, with the influent OLR (24.5 ± 0.9) kg COD/(m3 d) and hydraulic retention time (HRT) 2.7d during the stable operation phase. Meanwhile, this study demonstrated that 1.5–3.0 m/h would be the optimal Vup for the reactor, corresponding to the effluent recirculation of 32.5–78.0 m3/h. Moreover, it was found that the content of extracellular polymeric substances (EPS) in the anaerobic sludge increased from 50.3 to 140.7 mg/g volatile suspended solids (VSS), and the sludge had good granular performance during the reactor operation.

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Advanced Reactor Design, Operation and Economy

Water Science & Technology ◽

10.2166/wst.1986.0166 ◽

1986 ◽

Vol 18 (12) ◽

pp. 99-108 ◽

Cited By ~ 41

Author(s):

Gatze Lettinga ◽

Look Hulshoff Pol

Keyword(s):

Suspended Solids ◽

Granular Sludge ◽

High Rate ◽

Upflow Anaerobic Sludge Blanket ◽

Uasb Reactor ◽

Anaerobic Sludge ◽

Internal Circulation ◽

Inlet System ◽

Anaerobic Sludge Blanket ◽

Feed Inlet

Of the high rate anaerobic wastewater treatment systems the UASB (Upflow Anaerobic Sludge Blanket) reactor has found the widest application. Therefore the attention with respect to design, operation and economy will be focussed on this reactor type. In designing a UASB reactor specific attention is needed for the GSS (Gas-Solids Separator) device and the feed inlet system. For soluble wastewater generally no phase separation is required. Only for wastewaters high in suspended solids pre-acidification in a separate acidification reactor can be beneficial. Increasing attention is given to the development of modified UASB systems, such as a combination of a sludge bed reactor and an anaerobic filter. Other possible modified UASB systems may be found in a FS (Floating Settling) UASB reactor, the EGSB (Expanded Granular Sludge Bed) reactor and the UASB IC (Internal Circulation) reactor. As many factors are involved in the costs of a UASB reactor, only some rough data on reactor costs are presented.

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Methanogenic granule development in full scale internal circulation reactors

Water Science & Technology ◽

10.2166/wst.1994.0373 ◽

1994 ◽

Vol 30 (8) ◽

pp. 9-21 ◽

Cited By ~ 64

Author(s):

J. H. F. Pereboom ◽

T. L. F. M. Vereijken

Keyword(s):

Loading Rate ◽

Gas Production ◽

Full Scale ◽

Upflow Anaerobic Sludge Blanket ◽

Anaerobic Sludge ◽

Internal Circulation ◽

Methanogenic Activity ◽

Average Shear ◽

Biomass Retention ◽

Uasb Reactors

Internal Circulation (IC) reactors can be operated at higher reactor volume loading rates than Upflow Anaerobic Sludge Blanket (UASB) reactors. This results in increased gas production rates and subsequently higher average shear rates in IC-reactors. Furthermore, the liquid upflow velocity is 8-20 times higher, still granules develop successfully in IC-reactors. To investigate the granule development in IC-reactors and elucidate the process limitations with respect to granule development and biomass retention, granule samples from three full scale IC-reactors are characterized. Characterization included size distribution, strength, settling velocity, density, ash content and methanogenic activity. Granules were compared with samples from UASB reactors treating similar types of wastewaters. A hydrodynamic model was developed to describe the liquid circulation in IC reactors. The average shear rate in IC reactors is approximately twice as high compared to UASB-reactors. The two stage design of the IC-reactor allows 3-6 times higher loading rate. The experimental results showed that IC-granules are larger than UASB-granules grown on similar wastewater, while the strength of IC-granules is lower as a result of the higher sludge loading rate. Although wash-out is slightly enhanced in IC-reactors, the conditions in the second stage are tranquil enough to ensure adequate biomass retention in IC-reactors. The development of characteristic IC-granules after seeding proceeds within a few months. Physical characteristics of granules are determined mainly by biological factors.

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Modelling of ionic interactions with wastewater treatment biomass

Water Science & Technology ◽

10.2166/wst.2012.922 ◽

2012 ◽

Vol 65 (6) ◽

pp. 1014-1020 ◽

Cited By ~ 2

Author(s):

S. Westergreen ◽

C. J. Brouckaert ◽

K. M. Foxon

Keyword(s):

Cell Mass ◽

Weak Acid ◽

Anaerobic Digester ◽

Baker’S Yeast ◽

Proton Exchange ◽

Anaerobic Sludge ◽

Baker's Yeast ◽

Base Interaction ◽

Speciation Model ◽

Anaerobic Digester Sludge

Titration data for samples of mixed salts with glycine, baker's yeast cell mass and anaerobic digester sludge were obtained and compared to a speciation model of weak acid–base interaction in aqueous solutions. The effect of glycine on the buffer intensity of the solution could be precisely described by the speciation model but did not represent the proton exchange characteristics of either baker's yeast or anaerobic sludge well. A model component, UKZiNe, consisting of carboxylic acids, phosphate and amine groups described the baker's yeast well, and a combination of UKZiNe and carbonate-yielding inorganic solids described anaerobic digester sludge. The effect of biomass on buffer intensity in the pH range 6.5 to 8 was small for the concentration ranges tested.

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Biopaq®ICX: The next generation high rate anaerobic reactor proves itself at full scale

Water Practice & Technology ◽

10.2166/wpt.2019.066 ◽

2019 ◽

Vol 14 (4) ◽

pp. 802-807 ◽

Cited By ~ 1

Author(s):

T. L. G. Hendrickx ◽

B. Pessotto ◽

R. Prins ◽

L. Habets ◽

J. Vogelaar

Keyword(s):

Full Scale ◽

High Rate ◽

Anaerobic Sludge ◽

Next Generation ◽

Internal Circulation ◽

Anaerobic Reactor ◽

Loading Rates ◽

Biomass Retention ◽

Retention Device ◽

Volumetric Loading

Abstract The ICX (Internal Circulation eXperience) is the next generation high rate anaerobic reactor. The unique design with a two-stage phase separation device enables excellent biomass retention. The novel biomass retention device allows for high volumetric loading rates to be applied compared to IC (internal circulation) and UASB (Upflow Anaerobic Sludge Bed) reactors. Since the first demonstration test in 2013, more than 70 full scale ICX reactors have been built, ranging in size from 85 to 5,000 m3. This paper presents the results of the first ICX demonstration reactor (85 m3) and from a full scale ICX reference (350 m3). These results confirm that very high volumetric loading rates can be achieved with the ICX, whilst maintaining a stable and high COD removal efficiency. Biomass growth is clearly demonstrated in both the demonstration reactor and in the full scale reference, proving that efficient biomass retention is achieved in the ICX.

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Novel start-up process for the efficient degradation of high COD wastewater with up-flow anaerobic sludge blanket technology and a modified internal circulation reactor

Bioresource Technology ◽

10.1016/j.biortech.2020.123300 ◽

2020 ◽

Vol 308 ◽

pp. 123300 ◽

Cited By ~ 5

Author(s):

Jianfeng Liu ◽

Chengxian Wang ◽

Kai Wu ◽

Li Huang ◽

Zhengkang Tang ◽

...

Keyword(s):

Anaerobic Sludge ◽

Internal Circulation ◽

Start Up ◽

Anaerobic Sludge Blanket

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An experimental study on Bio-gas production by anaerobic digestion of RiceMill Wastewater (RMW)

Global NEST Journal ◽

10.30955/gnj.003442 ◽

2020 ◽

Vol 23 (1) ◽

pp. 35-42

Keyword(s):

Anaerobic Digestion ◽

Biogas Production ◽

Oxygen Demand ◽

Gas Production ◽

Anaerobic Digester ◽

Organic Loading Rate ◽

Anaerobic Sludge ◽

Working Volume ◽

Mesophilic Temperature ◽

Rice Mill Wastewater

<p>With the rising interest for sustainable power source and ecological security, anaerobic digestion of biogas technology has attracted considerable attention within the scientific researchers. This paper proposes a new research achievement on biogas production from Rice Mill Wastewater (RMW) with the utilization of anaerobic digester. An anaerobic digester is maintained with RMW and distillery anaerobic sludge at mesophilic temperature condition for 15 days as stabilization mode. After attaining stabilization stage, studies continued to examine the effect of Organic Loading Rate (OLR) and Hydraulic Retention Time (HRT) on the mesophilic anaerobic digestion of RMW. The OLR of the anaerobic reactor increased stepwise from 0.25 to 3.91 Kg COD/m3/dayand HRT ranged from 1 to 32.0 days. The total chemical oxygen demand (TCOD) utilized was higher than 75% and the CH4 percentage of the biogas was 62.00-63.00% for the OLRs studied. The efficient working volume of the digester is preserved as 25% of distillery anaerobic sludge and 75% of rice mill wastewater, loaded at Mesophilic temperature conditions for study purpose. By changing the conditions of OLR and HRT, biogas production, methane yield and percentage of COD reduction is examined. An anaerobic sludge is utilized as a seeding material to biodegrade the organic pollutants present in the wastewater. It will enhance the biological treatment of effluent with anaerobic sludge in a continuous mode of activity.The result showed that the proposed analysis obtains more biogas production with reduced COD when compared with existing approaches.</p>

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