Thermal hydrolysate as a carbon source for denitrification

Thermal hydrolysate is the liquid fraction (supernatant) of thermally treated wastewater sludge. The objective of the present study was to investigate the quality of thermal hydrolysate as a carbon source for denitrification. Steady state denitrification experiments in moving bed biofilm reactors were carried out. It was demonstrated that 2/3 of the COD in the thermal hydrolysate was utilised as a carbon source in the post denitrification step, with a retention time of 52 minutes. This degree of utilisation is about the same as reported for biological hydrolysate, which generally has been considered to be of better quality as a carbon source than thermal hydrolysate. The yield of soluble COD in the thermal hydrolysis process (180°C in 30 minutes) was found to be 28%. Typical COD-yields for biological hydrolysis are around 11%.

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Thermal hydrolysis for the production of carbon source for denitrification

Water Science & Technology ◽

10.2166/wst.1996.0393 ◽

1996 ◽

Vol 34 (1-2) ◽

pp. 371-378 ◽

Cited By ~ 19

Author(s):

John Barlindhaug ◽

Hallvard Ødegaard

Keyword(s):

Carbon Source ◽

Liquid Fraction ◽

Wastewater Sludge ◽

Treated Wastewater ◽

Design Experiment ◽

Thermal Hydrolysis ◽

Literature Study ◽

Hydrolysis Conditions ◽

Factorial Design Experiment

Thermal hydrolysate is the liquid fraction (supernatant) of thermally treated wastewater sludge. Based on a literature study, a factorial design experiment was carried out in order to investigate important condition-variables in the thermal hydrolysis step. The objective of the study was to investigate the influence on composition and amount of produced thermal hydrolysate, as well as the influence on the quality of hydrolysate as carbon source for denitrification, from varying hydrolysis conditions. The thermal hydrolysis experiments demonstrated that carbohydrates are the organic fraction that is most easily decomposed, while proteins are most easily solubilized. A small increase in the content of VFA was found during thermal hydrolysis, while fat did not seem to be affected. The varying hydrolysis conditions resulted in varying content of the produced hydrolysate, but the quality of the hydrolysate as carbon source did not vary dramatically with varying hydrolysis conditions.

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Carbon Source Recovery from Waste Activated Sludge by Low-Temperature Thermal Hydrolysis Process

Journal of Environmental Engineering ◽

10.1061/(asce)ee.1943-7870.0001631 ◽

2020 ◽

Vol 146 (1) ◽

pp. 04019098

Author(s):

Yuqi Wu ◽

Yinghe Jiang ◽

Kang Song

Keyword(s):

Low Temperature ◽

Carbon Source ◽

Activated Sludge ◽

Waste Activated Sludge ◽

Thermal Hydrolysis ◽

Hydrolysis Process

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Research on Removal Effects of Pollutants by the (A/O)4 SBR Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.648.385 ◽

2013 ◽

Vol 648 ◽

pp. 385-388

Author(s):

Kai Ji ◽

Na Wei ◽

Xiao Qing Yu ◽

Li Ding ◽

Jing Xiao

Keyword(s):

Carbon Source ◽

Removal Efficiency ◽

Retention Time ◽

Municipal Wastewater ◽

Hydraulic Retention Time ◽

Effluent Water ◽

Phosphorous Removal ◽

Sludge Retention Time ◽

Temperature Ranges

The staged SBR is the process that divides aeration and sedimentation process of conventional SBR into several stages in time, and operates under the conditions of different stages of anaerobic/oxic/anoxic alternation. The experiment mainly discussed the five-stage SBR with useful volume of 12 L for nitrogen and phosphorous removal of synthetic municipal wastewater in the temperature ranges of 15~30°C. Tests revealed that under the condition of hydraulic retention time (HRT) is 8 hours and sludge retention time (SRT) is 15 day, the removal efficiency of COD, NH3-N, TN and TP can reach to 88.9%, 99.61%, 78.9% and 94.21%. The quality of effluent water is good, and don’t need to add Carbon Source through the experiment.

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Reproducibility of biofilm processes and the meaning of steady state in biofilm reactors

Water Science & Technology ◽

10.2166/wst.2004.0880 ◽

2004 ◽

Vol 49 (11-12) ◽

pp. 359-364 ◽

Cited By ~ 41

Author(s):

Z. Lewandowski ◽

H. Beyenal ◽

D. Stookey

Keyword(s):

Steady State ◽

Biofilm Formation ◽

Surface Preparation ◽

Media Composition ◽

Biofilm Reactors ◽

Paper Address ◽

Natural Biofilms ◽

Temperature Surface

The need for reproducing biofilm processes is undisputable - the quality of biofilm research depends on this reproducibility. However, as many biofilm researchers know, long-term biofilm processes are notoriously difficult to reproduce. To avoid problems related to biofilm reproducibility two strategies are used: (1) to study very young biofilms that have accumulated for a few hours to a few days only, and (2) to run biofilm experiments only once. The first approach trades reproducibility for relevance because natural biofilms are usually older, often much older than a few days. This approach can be applied to answer questions relevant to initial events of biofilm formation but not questions relevant to long-term biofilm accumulation. The second approach conceals the problem of biofilm reproducibility. To assure reproducibility of biofilm processes, we methodically followed a procedure for growing biofilms in terms of microbial makeup, media composition, temperature, surface preparation, etc. Despite all this effort the reproducibility of our results for long term growth is unimpressive. Consequently, the question had to be asked: Are biofilm processes reproducible? The experiments described in this paper address this question. Biofilms grown in two identical and identically operated biofilm reactors had comparable structure only until the first sloughing event. After that, biofilms had different patterns of accumulation.

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Generation of an Effective Internal Carbon Source for Denitrification through Thermal Hydrolysis of Pre-Precipitated Sludge

Water Science & Technology ◽

10.2166/wst.1992.0497 ◽

1992 ◽

Vol 25 (4-5) ◽

pp. 211-218 ◽

Cited By ~ 12

Author(s):

G. Smith ◽

J. Göransson

Keyword(s):

Carbon Source ◽

Sewage Treatment ◽

Full Scale ◽

Metal Salts ◽

Organic Substances ◽

Thermal Hydrolysis ◽

Laboratory Studies ◽

Hydrolysis Process ◽

Pre Treatment ◽

Hydrolysis Of

Chemical pre-treatment with highly charged metal salts gives an effluent low in both organic substances and phosphorus. To use pre-precipitation as the first step in sewage treatment improves nitrification in the following biological step. The chemically precipitated sludge contains 75% or more of the organic substances in the raw sewage and can by a hydrolysis process be converted to readily degradable organic substances. This paper will review experiences from tests with thermal hydrolysis in a full scale plant as well as results from laboratory studies.

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Thermal hydrolysis to enhance energetic potential of sewage sludge: A review

Paliva ◽

10.35933/paliva.2021.02.05 ◽

2021 ◽

pp. 59-68

Author(s):

Anna Mágrová ◽

Pavel Jeníček

Keyword(s):

Sewage Sludge ◽

Biogas Production ◽

Treatment Plant ◽

Multicriteria Analysis ◽

Thermal Hydrolysis ◽

Digested Sludge ◽

Advantages And Disadvantages ◽

Input Material ◽

Hydrolysis Process

Sewage sludge biomass is a renewable energy source commonly produced by anaerobic digestion (AD). However, the limited biodegradability of sewage sludge causes a poor energy conversion of organic material into biogas and requires further enhancement. One possible solution is sludge disintegration by a thermal hydrolysis process (THP) that has already proven to enhance biogas production and improve the quality of digested sludge. This article reviews possible THP configurations, such as THP-AD, ITHP, and PAD-THP, together with different input materials and their impact on the energy balance of the wastewater treatment plant (WWTP). Data from full-scale THP demonstrate differences between the configurations and input material. Moreover, the general advantages and disadvantages of THP integration are summarized and presented as a multicriteria analysis that simplifies the decision-making whether the THP should be integrated in the WWTP.

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Effect of Cambi Thermal Hydrolysis Process–Anaerobic Digestion Treatment on Phthalate Plasticizers in Wastewater Sludge

Environmental Engineering Science ◽

10.1089/ees.2017.0207 ◽

2018 ◽

Vol 35 (3) ◽

pp. 210-218 ◽

Cited By ~ 3

Author(s):

Dana L. Armstrong ◽

Rebecca N. Hartman ◽

Clifford P. Rice ◽

Mark Ramirez ◽

Alba Torrents

Keyword(s):

Anaerobic Digestion ◽

Wastewater Sludge ◽

Thermal Hydrolysis ◽

Hydrolysis Process

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DECOLOURIZATION AND COD REMOVAL OF WASEWATER FROM ETHANOL PRODUCTION PROCESS FROM MOLASSES BY COAGULANTION USING INORGANIC ALUM

Science and Technology Development Journal ◽

10.32508/stdj.v13i3.2146 ◽

2010 ◽

Vol 13 (3) ◽

pp. 92-102

Author(s):

Trung Duc Le

Keyword(s):

Ethanol Production ◽

Oxygen Demand ◽

Cod Removal ◽

Treated Wastewater ◽

Treatment Processes ◽

Physico Chemical ◽

Biological Methods ◽

Treatment Step ◽

Main Material

The industrial production of ethanol by fermentation using molasses as main material that generates large quantity of wastewater. This wastewater contains high levels of colour and chemical oxygen demand (COD), that may causes serious environmental pollution. Most available treatment processes in Vietnam rely on biological methods, which often fail to treat waste water up to discharge standard. As always, it was reported that quality of treated wastewater could not meet Vietnameses discharge standard. So, it is necessary to improve the treatment efficiency of whole technological process and therefore, supplemental physico-chemical treatment step before biodegradation stage should be the appropriate choice. This study was carried out to assess the effect of coagulation process on decolourization and COD removal in molasses-based ethanol production wastewater using inorganic coaglutant under laboratory conditions. The experimental results showed that the reductions of COD and colour with the utilization of Al2(SO4)3 at pH 9.5 were 83% and 70%, respectively. Mixture FeSO4 – Al2(SO4)3 at pH 8.5 reduced 82% of colour and 70% of COD. With the addition of Polyacrylamide (PAM), the reduction efficiencies of colour, COD and turbidity by FeSO4 – Al2(SO4)3 were 87%, 73.1% and 94.1% correspondingly. It was indicated that PAM significantly reduced the turbidity of wastewater, however it virtually did not increase the efficiencies of colour and COD reduction. Furthermore, the coagulation processes using PAM usually produces a mount of sludge which is hard to be deposited.

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