Effect of low temperature thermal pre-treatment on the solubilization of organic matter, pathogen inactivation and mesophilic anaerobic digestion of poultry sludge

Many novel treatment technologies, usually representing a pre-treatment prior to the biological degradation process, have been developed in order to improve the recycling and reuse of sewage sludge. Among all the methods available, a chemical (alkaline) and a thermal treatment have been considered in this study. The behaviour of 13 substances belonging to different therapeutic classes (musks, tranquillisers, antiepileptic, anti-inflammatories, antibiotics, X-ray contrast media and estrogens) has been studied during the anaerobic digestion of sewage sludge combined with these pre-treatments (advanced operation) in comparison with the conventional process. Two parameters have been analysed: the temperature (mesophilic and thermophilic conditions) and the sludge retention time. While organic matter solubilization was higher with the alkaline process (55–80%), no difference between both pre-treatments was observed concerning volatile solids solubilization (up to 20%). The removal efficiencies of solids and organic matter during anaerobic digestion ranged from 40–70% and 45–75%, respectively. The higher removal efficiencies of pharmaceuticals and personal care products were achieved for the antibiotics, Naproxen and the natural estrogens (>80%). For the other compounds, the values were in the range 20–70%, except for Carbamazepine, which was not removed at any condition tested.

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The synergy of combined free nitrous acid and Fenton technology in enhancing anaerobic digestion of real sewage waste activated sludge

10.21203/rs.2.12384/v1 ◽

2019 ◽

Author(s):

Razieh Karimi ◽

Seyed Mostafa Hallaji

Keyword(s):

Organic Matter ◽

Anaerobic Digestion ◽

Activated Sludge ◽

Methane Production ◽

Nitrous Acid ◽

Waste Activated Sludge ◽

Free Nitrous Acid ◽

Digestion Process ◽

Treatment Technologies ◽

Pre Treatment

Abstract Background Recently, free nitrous acid (FNA) pre-treatment of sewage waste activated sludge has been introduced as an economically attractive and environmentally friendly technique for enhancing methane production from the anaerobic digestion process. Fenton pre-treatment of sewage sludge, as an advanced oxidation process, has also been introduced as a powerful technique for methane improvement in a couple of studies. This study, for the first time, investigates the synergy of combined FNA and Fenton pre-treatment technologies in enhancing the methane production from the anaerobic digestion process and reducing waste sludge to be disposed of. Actual secondary waste activated sludge in laboratory-scale batch reactors was used to assess the synergistic effect of the pre-treatments. The mechanisms behind the methane enhancement were also put into perspective by measuring different microbial enzymes activity and solubilisation of organic matter. Result This study revealed that the combined pre-treatments release organic matter into the soluble phase significantly more than the bioreactors pre-treated with individual FNA and Fenton. For understanding the influence of pre-treatments on solubilisation of organic matter, soluble protein, soluble polysaccharide and soluble chemical oxygen demand (SCOD) were measured before and after the treatments and it was shown that they respectively increased by 973%, 33% and 353% after the treatments. Protease and cellulose activity, as the key constituents of the microbial community presenting in activated sludge, decreased considerably within the combined pre-treatments (42% and 32% respectively) and methane production enhanced by 43-69%. Furthermore, total solids and volatile solids destruction improved by 26% and 24% at the end of anaerobic digestion, which can reduce transport costs of sludge and improve the quality of sludge for application in farms and forests. Conclusions The results obtained from the experiments corroborate the synergic effect of the combined FNA and Fenton pre-treatment technologies in degrading the organic and microbial constituents in waste activated sludge, which improved methane production accordingly. This is of paramount importance because the total costs of wastewater treatment plants operation and greenhouse gas emission from sludge treatment and disposal processes would reduce considerably, which pave the way for the implementation of these technologies.

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Adsorption characteristic of organic matter by low-temperature dry cattle manure-derived anaerobic digestion

10.5004/dwt.2021.27180 ◽

2021 ◽

Vol 225 ◽

pp. 76-85

Author(s):

Yao Zhu ◽

Baojun Yi ◽

Zhixi Zong ◽

Xueqi Yang ◽

Meijing Chen ◽

...

Keyword(s):

Organic Matter ◽

Anaerobic Digestion ◽

Low Temperature ◽

Cattle Manure ◽

Adsorption Characteristic

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Fate of organic matter during moderate heat treatment of sludge: kinetics of biopolymer and hydrolytic activity release and impact on sludge reduction by anaerobic digestion

Water Science & Technology ◽

10.2166/wst.2014.083 ◽

2014 ◽

Vol 69 (9) ◽

pp. 1828-1833 ◽

Cited By ~ 1

Author(s):

D. Lefebvre ◽

V. Dossat-Létisse ◽

X. Lefebvre ◽

E. Girbal-Neuhauser

Keyword(s):

Heat Treatment ◽

Organic Matter ◽

Anaerobic Digestion ◽

Humic Acid ◽

Hydrolytic Enzymes ◽

Oxygen Demand ◽

Hydrolytic Activity ◽

Water Phase ◽

Pre Treatment ◽

Kinetics Of

Temperature-phased anaerobic digestion with a 50–70 °C pre-treatment is widely proposed for sludge. Here, such a sludge pre-treatment (65 °C) was studied against the physical, enzymatic and biodegradation processes. The soluble and particulate fractions were analysed in terms of biochemical composition and hydrolytic enzymatic activities. Two kinetics of organic matter solubilisation were observed: a rapid transfer of the weak-linked biopolymers to the water phase, including sugars, proteins or humic acid-like substances, to the water phase, followed by a slow and long-term solubilisation of proteins and humic acid-like substances. In addition, during the heat treatment a significant pool of thermostable hydrolytic enzymes including proteases, lipases and glucosidases remains active. Consequently, a global impact on organic matter was the transfer of the biodegradable chemical oxygen demand (COD) from the particulate to the soluble fraction as evaluated by the biological methane potential test. However, the total biodegradable COD content of the treated sludge remained constant. The heat process improves the bio-accessibility of the biodegradable molecules but doesn't increase the inherent sludge biodegradability, suggesting that the chemistry of the refractory proteins and humic acids seems to be the real limit to sludge digestion.

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Thermal pre-treatment of primary and secondary sludge at 70 °°C prior to anaerobic digestion

Water Science & Technology ◽

10.2166/wst.2005.0512 ◽

2005 ◽

Vol 52 (1-2) ◽

pp. 161-166 ◽

Cited By ~ 53

Author(s):

I.V. Skiadas ◽

H.N. Gavala ◽

J. Lu ◽

B.K. Ahring

Keyword(s):

Organic Matter ◽

Anaerobic Digestion ◽

Low Cost ◽

Methane Recovery ◽

Primary Sludge ◽

Thermophilic Anaerobic Digestion ◽

Secondary Sludge ◽

Thermophilic Digestion ◽

Pre Treatment ◽

Digestion Step

In general, mesophilic anaerobic digestion of sewage sludge is more widely used compared to thermophilic digestion, mainly because of the lower energy requirements and higher stability of the process. However, the thermophilic anaerobic digestion process is usually characterised by accelerated biochemical reactions and higher growth rate of microorganisms resulting in an increased methanogenic potential at lower hydraulic retention times. Furthermore, thermal pre-treatment is suitable for the improvement of stabilization and could be realized at relatively low cost especially at low temperatures. The present study investigates the effect of the pre-treatment at 70 °C on thermophilic (55 °C) anaerobic digestion of primary and secondary sludge in continuously operated digesters. Thermal pre-treatment of primary and secondary sludge at 70 °C enhanced the removal of organic matter and the methane production during the subsequent anaerobic digestion step at 55 °C. It also greatly contributed to the destruction of pathogens present in primary sludge. Finally it results in enhanced microbial activities of the subsequent anaerobic step suggesting that the same efficiencies in organic matter removal and methane recovery could be obtained at lower HRTs.

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Process optimization and effect of thermal, alkaline, H2O2 Oxidation and combination pre-treatment of sewage sludge on solubilisation and anaerobic digestion

10.21203/rs.2.19967/v1 ◽

2020 ◽

Author(s):

Salar Siami ◽

Behnoush Aminzadeh ◽

Razieh Karimi ◽

Seyed Mostafa Hallaji

Keyword(s):

Hydrogen Peroxide ◽

Response Surface Methodology ◽

Organic Matter ◽

Anaerobic Digestion ◽

Sewage Sludge ◽

Thermal Energy ◽

Methane Production ◽

Quadratic Model ◽

Waste Activated Sludge ◽

Pre Treatment

Abstract Background This study investigated the feasibility of enhancing anaerobic digestion of sewage sludge with triple, dual, and individual pre-treatment of waste activated sludge with heat, alkalinity, and hydrogen peroxide. These pre-treatments disrupt sludge flocs, organisms’ cell walls, extracellular polymeric substance, and intracellular organic matter, which increase biodegradability and hydrolysis rate of organic matter. In addition, the influence of various variables on methane production was analyzed using the response surface methodology with the quadratic model. Eventually, an optimized temperature and chemical concentration for the highest methane production and lowest chemical usage is suggested.Results The highest amount of methane production was obtained from the sludge pretreated with triple pretreatment (heat (90°C), alkalinity (pH=12), and hydrogen peroxide (30 mg H2O2 /g TS)), which had better performance with 96% higher than that of the control sample with Temperature of 25°C approximately and alkalinity of pH=8. Response surface methodology with the quadratic model was also used for analyzing the influence of temperature, pH, and hydrogen peroxide concentration on anaerobic digestion efficiency. It was revealed that the optimized temperature, pH, and hydrogen peroxide concentration for maximizing methane production and solubilisation of organic matter and minimizing thermal energy and chemical additives of the pre-treatments are 83.2°C, pH=10.6 and 34.8 mg H2O2 /g TS, respectively, has the desirability of 0.67.Conclusion This study reveals that triple pre-treatment of waste activated sludge performs better than dual and individual pre-treatment, Respectively. The enhanced methane production can be used as an important renewable energy resource in wastewater treatment plants for producing electrical and thermal energy. Furthermore, exploiting a higher amount of methane in the anaerobic digestion stage decreases methane emission to the atmosphere in dewatering and landfilling stages and enhances the quality of digested sludge, bringing about environmentally friendly and economically attractive sewage sludge treatment process.

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Influence of low temperature thermal pre-treatment on sludge solubilisation, heavy metal release and anaerobic digestion

Bioresource Technology ◽

10.1016/j.biortech.2010.02.068 ◽

2010 ◽

Vol 101 (15) ◽

pp. 5743-5748 ◽

Cited By ~ 232

Author(s):

Lise Appels ◽

Jan Degrève ◽

Bart Van der Bruggen ◽

Jan Van Impe ◽

Raf Dewil

Keyword(s):

Heavy Metal ◽

Anaerobic Digestion ◽

Low Temperature ◽

Metal Release ◽

Pre Treatment ◽

Heavy Metal Release

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Sludge minimization by disintegration at different wastewater treatment plants

Water Practice & Technology ◽

10.2166/wpt.2008.010 ◽

2008 ◽

Vol 3 (1) ◽

Author(s):

Luchien Luning ◽

Paul Roeleveld ◽

Victor W.M. Claessen

Keyword(s):

Organic Matter ◽

Wastewater Treatment ◽

Anaerobic Digestion ◽

Sewage Sludge ◽

New Technologies ◽

Wastewater Treatment Plants ◽

Treatment Plant ◽

Biological Degradation ◽

Ongoing Research ◽

Sludge Minimization

In recent years new technologies have been developed to improve the biological degradation of sewage sludge by anaerobic digestion. The paper describes the results of a demonstration of ultrasonic disintegration on the Dutch Wastewater Treatment Plant (WWTP) Land van Cuijk. The effect on the degradation of organic matter is presented, together with the effect on the dewatering characteristics. Recommendations are presented for establishing research conditions in which the effect of sludge disintegration can be determined in a more direct way that is less sensitive to changing conditions in the operation of the WWTP. These recommendations have been implemented in the ongoing research in the Netherlands supported by the National Institute for wastewater research (STOWA).

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Low temperature CO2 capture on biomass-derived KOH-activated hydrochar established through hydrothermal carbonization with water-soaking pre-treatment

Journal of Environmental Chemical Engineering ◽

10.1016/j.jece.2021.105074 ◽

2021 ◽

Vol 9 (2) ◽

pp. 105074

Author(s):

Nurul Azrin Zubbri ◽

Abdul Rahman Mohamed ◽

Pooya Lahijani ◽

Maedeh Mohammadi

Keyword(s):

Low Temperature ◽

Co2 Capture ◽

Hydrothermal Carbonization ◽

Pre Treatment

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A Framework Based on Finite Element Method (FEM) for Modelling and Assessing the Affection of the Local Thermal Weather Factors on the Performance of Anaerobic Lagoons for the Natural Treatment of Swine Wastewater

Water ◽

10.3390/w13070882 ◽

2021 ◽

Vol 13 (7) ◽

pp. 882

Author(s):

Saulo Brito-Espino ◽

Alejandro Ramos-Martín ◽

Sebastian O. Pérez-Báez ◽

Carlos Mendieta-Pino ◽

Federico Leon-Zerpa

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Organic Matter ◽

Anaerobic Digestion ◽

Environmental Sustainability ◽

Diffusion Reaction ◽

Swine Wastewater ◽

Natural Treatment ◽

Element Method ◽

Anaerobic Lagoons

Anaerobic lagoons are natural wastewater treatment systems suitable for swine farms in small communities due to its low operational and building costs, as well as for the environmental sustainability that these technologies enable. The local weather is one of the factors which greatly influences the efficiency of the organic matter degradation within anaerobic lagoons, since microbial growth is closely related to temperature. In this manuscript, we propose a mathematical model which involves the two-dimensional Stokes, advection–diffusion-reaction and heat transfer equations for an unstirred fluid flow. Furthermore, the Anaerobic Digestion Model No1 (ADM1), developed by the International Water Association (IWA), has been implemented in the model. The partial differential equations resulting from the model, which involve a large number of state variables that change according to the position and the time, are solved through the use of the Finite Element Method. The results of the simulations indicated that the methodology is capable of predicting reasonably well the steady-state of the concentrations for all processes that take place in the anaerobic digestion and for each one of the variables considered; cells, organic matter, nutrients, etc. In view of the results, it can be concluded that the model has significant potential for the design and the study of anaerobic cells’ behaviour within free flow systems.

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