Biodeterioration mechanisms and kinetics of SCM and aluminate based cements and AAM in the liquid phase of an anaerobic digestion

In biogas structures, concrete faces aggressive media during anaerobic digestion. Biological activities allow the conversion of organic matter into biogas, leading to a medium characterized by a variability of composition in time and space. In order to ensure the sustainability of this expanding industry, solutions for increasing concrete durability are needed. This study aims to analyse the deterioration mechanisms of different binders focusing on the impact of the binder nature on the medium (biochemical composition) during the digestion. Binders with favourable composition to chemically aggressive media were tested: slag cement (CEM III/B), calcium aluminate cement (CAC) and metakaolin-based alkaliactivated material (MKAA), and a reference binder: OPC (CEM I). They were exposed to three anaerobic digestion cycles in liquid phase in laboratory bioreactors. The organic acids and ammonium concentrations of the liquid phase were monitored by GC and HPIC. For OPC and slag cement pastes, the chemical and mineralogical changes were characterized by SEM/EDS and XRD. Locally, the presence of binder materials has an impact on the kinetics of the digestion reaction, and therefore on the quantities of gas produced. Ammonium concentrations were above the XA3 class range. Under the conditions explored, biodeterioration mainly led to the carbonation of cement pastes.

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Biogas Potential from the Anaerobic Digestion of Potato Peels: Process Performance and Kinetics Evaluation

Energies ◽

10.3390/en12122311 ◽

2019 ◽

Vol 12 (12) ◽

pp. 2311 ◽

Cited By ~ 16

Author(s):

Spyridon Achinas ◽

Yu Li ◽

Vasileios Achinas ◽

Gerrit Jan Willem Euverink

Keyword(s):

Anaerobic Digestion ◽

Energy Recovery ◽

Biogas Production ◽

Combined Treatment ◽

Methane Yield ◽

Cow Manure ◽

Potato Peel ◽

Potato Peels ◽

The Impact ◽

Kinetics Of

This article intends to promote the usage of potato peels as efficient substrate for the anaerobic digestion process for energy recovery and waste abatement. This study examined the performance of anaerobic digestion of potato peels in different inoculum-to-substrate ratios. In addition, the impact of combined treatment with cow manure and pretreatment of potato peels was examined. It was found that co-digestion of potato peel waste and cow manure yielded up to 237.4 mL CH4/g VSadded, whereas the maximum methane yield from the mono-digestion of potato peels was 217.8 mL CH4/g VSadded. Comparing the co-digestion to mono-digestion of potato peels, co-digestion in PPW/CM ratio of 60:40 increased the methane yield by 10%. In addition, grinding and acid hydrolysis applied to potato peels were positively effective in increasing the methane amount reaching 260.3 and 283.4 mL CH4/g VSadded respectively. Likewise, compared to untreated potato peels, pretreatment led to an elevation of the methane amount by 9% and 17% respectively and alleviated the kinetics of biogas production.

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Anaerobic Digestion of Solid Wastes Needs Research to Face an Increasing Industrial Success

International Journal of Chemical Reactor Engineering ◽

10.2202/1542-6580.1619 ◽

2008 ◽

Vol 6 (1) ◽

Cited By ~ 12

Author(s):

Pierre Buffiere ◽

Liliana Delgadillo Mirquez ◽

Jean Philippe Steyer ◽

Nicolas Bernet ◽

Jean Philippe Delgenes

Keyword(s):

Organic Matter ◽

Anaerobic Digestion ◽

Methane Production ◽

Biochemical Parameters ◽

Energy Production ◽

Solid Wastes ◽

High Complexity ◽

Intrinsic Kinetics ◽

Anaerobic Biodegradability ◽

Kinetics Of

Anaerobic digestion of solid wastes is an emerging solution for both waste management and energy production. The high complexity of the process is mostly attributed to the absence of descriptors for the design and the prediction of such a process. This paper presents an approach for the description of organic matter based on several biochemical parameters, established on 22 different organic wastes. The lignocellulosic content is the most important parameter for the prediction of anaerobic biodegradability and methane production; in addition, the knowledge of the carbohydrate, lipid and protein contents is also crucial and makes possible a prediction of the intrinsic kinetics of the reaction.

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The Effect of Fine-Ground Glass on the Hydration Process and Properties of Alumina-Cement-Based Composites

Materials ◽

10.3390/ma14164633 ◽

2021 ◽

Vol 14 (16) ◽

pp. 4633

Author(s):

Galyna Kotsay ◽

Irmina Masztakowska

Keyword(s):

Calcium Aluminate ◽

Calcium Aluminate Cement ◽

Ground Glass ◽

High Alumina ◽

Cement Pastes ◽

Alumina Cement ◽

High Alumina Cement ◽

Mortar Strength ◽

The Impact ◽

Aluminate Cement

This paper discusses studies regarding the impact of fine-ground glass additives on the hydration and properties of alumina cement pastes and mortars. Fine-ground glass was added to pastes and mortars instead of high-alumina cement and calcium aluminate cement in quantities of 5% and 10%. The findings are inconclusive as to the impact of glass on the properties of tested alumina cement types. The effect produced via the addition of glass instead of cement depends on the type of alumina cement used. Adding fine-ground glass to high-alumina cement enhances the paste’s density while improving paste and mortar strength. Using the same additive for calcium aluminate cement reduces its density and strength. The addition of glass to high-alumina cement adversely affects its strength at higher temperatures.

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Effect of SRA on the Course of Hydration of Cement Composites

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.296.35 ◽

2019 ◽

Vol 296 ◽

pp. 35-40

Author(s):

Lucia Osuská ◽

Martin Ťažký ◽

Milan Meruňka ◽

Rudolf Hela

Keyword(s):

Liquid Phase ◽

Chemical Reaction ◽

Cement Hydration ◽

Cement Composites ◽

Mechanical Parameters ◽

Curing Time ◽

Volume Changes ◽

Cement Pastes ◽

Binder Component ◽

The Impact

Cement hydration is a chemical reaction that is associated with the development of hydration heat and changes in the volume of input components that transit from the solid and liquid phase to one homogeneous whole. In order to eliminate the volume changes already occurring during the hydration process, several principles can be applied, such as the use of active or inert admixtures as partial cement substitute or special shrinkage reducing additives. The experiment verifies the effect of anti-shrinkage additives on the course of hydration of cement pastes in terms of the development of hydration temperatures and elimination of volume changes of cement pastes. Volume changes will be monitored for the first 30 hours of cement mixing with water, i.e. in the time when the major changes occur due to this chemical reaction. Due to the expected hydration deceleration of the binder component by the effect of SRA, the impact of the use of these additives on the curing time of the composite and consequently on the mechanical parameters of the concrete will be verified.

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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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Evaluating the level of ammonia and sulfide in the liquid phase during anaerobic digestion of slaughterhouse waste operating at mesophilic scale digester—the impact of inhibition and process performance

AIMS Energy ◽

10.3934/energy.2020.4.615 ◽

2020 ◽

Vol 8 (4) ◽

pp. 615-626 ◽

Cited By ~ 1

Author(s):

Eric Mutegoa ◽

◽

Isack Kandola ◽

Askwar Hilonga ◽

Karoli N. Njau ◽

...

Keyword(s):

Anaerobic Digestion ◽

Liquid Phase ◽

Process Performance ◽

The Impact

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Modeling the effect of microscale heterogeneities on soil bacterial dynamics and the impact on soil functions

10.5194/egusphere-egu21-1265 ◽

2021 ◽

Author(s):

Simon Zech ◽

Nadja Ray ◽

Thomas Ritschel ◽

Kai Uwe Totsche ◽

Alexander Prechtel

Keyword(s):

Organic Matter ◽

Liquid Phase ◽

Reactive Transport ◽

Geodesic Distance ◽

Mechanistic Model ◽

Bacterial Species ◽

Soil Samples ◽

Multiphase Model ◽

Order Kinetic ◽

The Impact

There is still no satisfactory understanding of the factors that enable soil microbial populations to be as highly diverse as they are. Mathematically based modeling can facilitate the understanding of their development and function in soils, e.g. with respect to habitat and carbon cycling.Our mechanistic model is based on [1,2] and allows studying the spatiotemporal dynamics of bacteria in unsaturated soil samples. In this presentation, different levels of saturation are investigated, for which the fluid (liquid and gas) distributions are calculated according to a morphological model. As in [3] various bacteria strains and organic matter are heterogeneously distributed in CT scans of various soil samples.The bacteria strains grow based on Michaelis-Menten kinetics due to the uptake of oxygen and dissolved organic carbon (DOC) present in the liquid phase. The development of bacterial colonies is realized in a cellular automaton framework (CAM) as presented in [1,2]. DOC is either present as a carbonaceous solution or hydrolized by a first order kinetic from heterogeneously distributed particulate organic matter (POM) sources. The diffusion of both nutrients oxygen and DOC are described by means of reactive transport equations, which include a Henry conditions for the transfer from/into the gas phase. We apply the local discontinuous Galerkin (LDG) method as a discretization scheme.Our simulations show that the impact heterogeneity in nutrient and bacteria distribution has on overall biodegradation kinetics strongly depends on the scale of interest. On the scale of soil microaggregates (<250 &#956;m), only very specific cases can be distinguished globally, e.g. when nutrient sources are isolated from bacteria due to a disconnected liquid phase. Locally however, heterogeneities in nutrient distribution impact the development of bacteria populations, e.g. a lower geodesic distance of bacteria to nutrient promotes bacteria growth locally. Such local effects can have an important role for competing bacterial species. On larger scales (millimeter scale), such heterogeneities can also have a large impact. We conclude that the heterogeneous spatial structure must be resolved scale-dependently.&#160;&#160;[1] N. Ray, A. Rupp and A. Prechtel. Discrete-continuum multiscale model for transport, biomass development and solid restructuring in porous media, Adv. Water Resour. 107, 393-404 (2017), doi:10.1016/j.advwatres.2017.04.001.[2] A. Rupp, K. Totsche, A. Prechtel and N. Ray. Discrete-continuum multiphase model for structure formation in soils including electrostatic effects, Front. Environ. Sci. 6:96 (2018), doi:10.3389/fenvs.2018.00096.[3] X. Portell, V. Pot, P. Garnier, W. Otten and P.C. Baveye. Microscale heterogeneity of the spatial distribution of organic matter can promote bacterial biodiversity in soils: insights from computer simulations., Front. Microbiol. 9:1583 (2018), doi:10.3389/fmicb.2018.01583.

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Effect of feed/inoculum ratio on anaerobic digestion of sonicated sludge

Water Science & Technology ◽

10.2166/wst.2006.549 ◽

2006 ◽

Vol 54 (5) ◽

pp. 77-84 ◽

Cited By ~ 23

Author(s):

C.M. Braguglia ◽

G. Mininni ◽

M.C. Tomei ◽

E. Rolle

Keyword(s):

Organic Matter ◽

Anaerobic Digestion ◽

Beneficial Effect ◽

Biogas Production ◽

Soluble Form ◽

Excess Sludge ◽

Experimental Conditions ◽

Digestion Process ◽

Anaerobic Reactors ◽

Kinetics Of

In recent years, relevant interest has been devoted to activated sludge disintegration and solubilisation techniques in order to cope with the biological limitations related to particulate degradation. Mechanical disintegration with ultrasound can efficiently transform insoluble organics into a soluble form: the solubilised organic matter is released from the cells to the bulk phase, thus accelerating the hydrolysis step in the digestion process. Experiments were carried out on bench scale anaerobic reactors fed with either untreated or disintegrated excess sludge, added with a biomass inoculum taken from a full scale anaerobic digester. Digestion tests have been carried out at different feed/inoculum ratios (F/I) in the range of 0.1–2, kinetics of VS reduction has been investigated and a beneficial effect of sonication is observed for all the experimental conditions. Similar beneficial results have also been found for biogas production with a maximum gain of 25% at 0.5 F/I ratio.

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