Conversion of organic waste into volatile fatty acids – The influence of process operating parameters

Volatile fatty acids (VFAs) are proposed platform molecules for the production of basic chemicals and polymers from organic waste streams. A simple bio-reactor was fabricated with locally available materials to conduct this study. A lab-scale anaerobic batch reactor was fed with potato waste and banana waste as substrate to find out the potential organic waste that has maximum VFAs production capacity. Between these two wastes, banana waste was found better for VFAs production. The product spectrum remained similar at the pH range 4.0-4.5 but higher pH reduced the VFAs production. The operation of anaerobic digestion with uncontrolled pH reduced the pH 4.0 to 4.5. Therefore, it is better to run the anaerobic digestion without controlling the pH while aiming to VFAs production. A small amount nutrient (ammonium nitrogen) significantly increases the VFAs production but higher amount nutrient has an inhibition effect. However commercial surfactant has a strong inhibition effect on VFAs producing organism and hence reduced the VFAs production. The efficient production of VFA at uncontrolled pH with a small amount of ammonium nitrogen increases the economic feasibility of organic waste-based VFAs production.

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Development of headspace–gas chromatography–flame ionization detection procedure to determine volatile fatty acids in zoo organic waste leachates

Water Science & Technology ◽

10.2166/wst.2011.516 ◽

2011 ◽

Vol 63 (12) ◽

pp. 2873-2877 ◽

Cited By ~ 2

Author(s):

Anna Banel ◽

Marta Wasielewska ◽

Monika Felchner-Żwirełło ◽

Bogdan Zygmunt

Keyword(s):

Fatty Acids ◽

Gas Chromatography ◽

Organic Waste ◽

Volatile Fatty Acids ◽

Sample Introduction ◽

Flame Ionization Detection ◽

Monocarboxylic Acids ◽

Ionization Detection ◽

Flame Ionization ◽

Headspace Gas

In order to determine volatile fatty acids (short chain monocarboxylic acids with 2 to 6 carbon atoms in a molecule) in leachates formed in organic waste piles a procedure based on static headspace (HS) coupled with gas chromatography (GC) have been proposed and optimized. The conditions of HS extraction and sample introduction into a gas chromatograph as well as of chromatographic separation were considered. Using flame ionization detection LODs were of the order of 0.02– 0.37 mg/L. The analyzed leachate collecting on and close to a zoo organic waste pile contained VFAs (Volatile Fatty Acids) at a concentration ranging from 5.5 mg/L to 0.88 g/L and from below LOD to 10.1 mg/L for pool water at some distance from the pile, respectively.

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Rapid generation of volatile fatty acids (VFA) through anaerobic acidification of livestock organic waste at low hydraulic residence time (HRT)

Bioresource Technology ◽

10.1016/j.biortech.2017.04.005 ◽

2017 ◽

Vol 238 ◽

pp. 188-193 ◽

Cited By ~ 21

Author(s):

Kranti Kuruti ◽

Shalini Nakkasunchi ◽

Sameena Begum ◽

Sudharshan Juntupally ◽

Vijayalakshmi Arelli ◽

...

Keyword(s):

Fatty Acids ◽

Residence Time ◽

Organic Waste ◽

Volatile Fatty Acids ◽

Hydraulic Residence Time ◽

Anaerobic Acidification ◽

Rapid Generation

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Physiology and Rumen Microbial Ecology of Goats Fed Municipal Organic Solid Wastes Treated with Diastic Microbes from Snail (Achatina achatina)

Annual Research & Review in Biology ◽

10.9734/arrb/2021/v36i1030438 ◽

2021 ◽

pp. 82-94

Author(s):

Agida, Christopher Agboje ◽

Essien Ekpenyong Nsa ◽

Uduakobong Essien John ◽

Constance Ihuoma Adje ◽

A. N. Chukwuemela ◽

...

Keyword(s):

Fatty Acids ◽

Microbial Ecology ◽

Solid Waste ◽

Organic Waste ◽

Volatile Fatty Acids ◽

Panicum Maximum ◽

Total Volatile ◽

Organic Solid Waste ◽

Organic Solid ◽

Municipal Organic Solid Waste

The experiment was conducted with the objective of providing more information on the physiology and rumen microbial ecology of goats fed municipal organic solid waste treated with Diastic microbes of snails (Achatina achatina). The study was on the treated and untreated municipal organic solid waste as components of experimental diet. Balanced rations containing diets; A = 45% untreated municipal organic waste (UMOW), B = 45% treated municipal organic waste (TMOW), and C = 70% treated municipal organic waste (TMOW), with wheat offal, palm kernel cake, and molasses used to balance the diets. Where grass/legume ratio of 3 parts of Panicum maximum and 1 part of Centrocema were fed across treatments at the same proportion. The three rations were fed to 18 unsex Red Sokoto goats aged between 6 to 7 months, with an average weight of 8.01±2.50kg. They were housed in pens, on a floor space of 0.5 to 0.75m2 in a completely randomized designed experiment replicated six times and fed for a period of 52 days. The results were separated according to the parameters of rumen physiology (pH, total volatile fatty acids, acetic, propionic, butyric acids and ethanol, and rumen ecology (bacteria, protozoa, and fungi, which are mainly anaerobic microbes). The investigations revealed that microbial (bacteria, protozoa and fungi) load counts were significantly (p<0.05) influenced by dietary treatments. While the total volatile fatty acids (TVFA), acetic, butyric and propionic increased (p<0.05) except for the TVFA and the propionic acid that showed numerical (p>0.05) increased levels of (TMOW). The pH levels improved (p>0.05) between 6.7 to 6.8 where the rumen electrolytes (Ca, Na and K) increased (p<0.01) with increased levels of TMOW. Rumen moisture, dry matter and fat content were (p<0.01) influenced by TMOW diets while ash content was (p<0.01) influenced by the TMOW. Crude protein, ether extract, crude fibre and carbohydrate were not affected (p<0.01; p<0.05) affected. It is good to note that, the microbial community of snail used in the pre-feeding fermentation of municipal organic waste had influence in the physiology and rumen microbial ecology at interface with the goat, enhanced improved the organic matter degradation and feed quality, of the highly fibrous municipal organic solid waste.

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Production of volatile fatty acids through co-digestion of sewage sludge and external organic waste: Effect of substrate proportions and long-term operation

Waste Management ◽

10.1016/j.wasman.2020.05.027 ◽

2020 ◽

Vol 112 ◽

pp. 30-39 ◽

Cited By ~ 6

Author(s):

Isaac Owusu-Agyeman ◽

Elzbieta Plaza ◽

Zeynep Cetecioglu

Keyword(s):

Fatty Acids ◽

Sewage Sludge ◽

Organic Waste ◽

Volatile Fatty Acids ◽

Term Operation

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Valorization of volatile fatty acids derived from low-cost organic waste for lipogenesis in oleaginous microorganisms-A review

Bioresource Technology ◽

10.1016/j.biortech.2020.124457 ◽

2021 ◽

Vol 321 ◽

pp. 124457

Author(s):

Alok Patel ◽

Omprakash Sarkar ◽

Ulrika Rova ◽

Paul Christakopoulos ◽

Leonidas Matsakas

Keyword(s):

Fatty Acids ◽

Organic Waste ◽

Volatile Fatty Acids ◽

Low Cost ◽

Oleaginous Microorganisms

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Unravelling a microbial synergy to boost caproate production via carboxylates chain elongation with ethanol

HKIE Transactions ◽

10.33430/v26n2thie-2018-0041 ◽

2019 ◽

Vol 26 (2) ◽

pp. 63-71

Author(s):

Ling Leng ◽

Ying Wang ◽

Peixian Yang ◽

Takashi Narihiro ◽

Masaru Konishi Nobu ◽

...

Keyword(s):

Fatty Acids ◽

Volatile Fatty Acids ◽

Microbial Consortia ◽

Chain Elongation ◽

Desulfovibrio Vulgaris ◽

Rrna Gene ◽

Selective Enrichment ◽

Microbial Network ◽

Cost Efficient ◽

Rrna Gene Sequencing

Chain elongation of volatile fatty acids for medium chain fatty acids production (e.g. caproate) is an attractive approach to treat wastewater anaerobically and recover resource simultaneously. Undefined microbial consortia can be tailored to achieve chain elongation process with selective enrichment from anaerobic digestion sludge, which has advantages over pure culture approach for cost-efficient application. Whilst the metabolic pathway of the dominant caproate producer, Clostridium kluyveri, has been annotated, the role of other coexisting abundant microbiomes remained unclear. To this end, an ethanol-acetate fermentation inoculated with fresh digestion sludge at optimal conditions was conducted. Also, physiological study, thermodynamics and 16 S rRNA gene sequencing to elucidate the biological process by linking the system performance and dominant microbiomes were integrated. Results revealed a possible synergistic network in which C. kluyveri and three co-dominant species, Desulfovibrio vulgaris, Fusobacterium varium and Acetoanaerobium sticklandii coexisted. D. vulgaris and A. sticklandii (F. varium) were likely to boost the carboxylates chain elongation by stimulating ethanol oxidation and butyrate production through a syntrophic partnership with hydrogen (H2) serving as an electron messenger. This study unveils a synergistic microbial network to boost caproate production in mixed culture carboxylates chain elongation.

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