Similar evolution in δ 13CH4 and model-predicted relative rate of aceticlastic methanogenesis during mesophilic methanization of municipal solid wastes

Similar evolution was obtained for the stable carbon isotope signatures δ 13CH4 and the model-predicted relative rate of aceticlastic methanogenesis during mesophilic methanization of municipal solid wastes. In batch incubations, the importance of aceticlastic and hydrogenotrophic methanogenesis changes in time. Initially, hydrogenotrophic methanogenesis dominated, but increasing population of Methanosarcina sp. enhances aceticlastic methanogenesis. Later, hydrogenotrophic methanogenesis intensified again. A mathematical model was developed to evaluate the relative contribution of hydrogenotrophic and aceticlastic pathways of methane generation during mesophilic batch anaerobic biodegradation of the French and the Chinese Municipal Solid Wastes (FMSW and CMSW). Taking into account molecular biology analysis reported earlier three groups of methanogens including strictly hydrogenotrophic methanogens, strictly aceticlastic methanogens (Methanosaeta sp.) and Methanosarcina sp., consuming both acetate and H2/H2CO3 were considered in the model. The total organic and inorganic carbon concentrations, methane production volume, methane and carbon dioxide partial pressures values were used for the model calibration and validation. Methane isotopic composition (δ 13CH4) evolution during the incubations was used to independently validate the model results. The model demonstrated that only the putrescible solid waste was totally converted to methane.

Download Full-text

Acetate turnover and methanogenic pathways in Amazonian lake sediments

10.5194/bg-2019-411 ◽

2019 ◽

Author(s):

Ralf Conrad ◽

Melanie Klose ◽

Alex Enrich-Prast

Keyword(s):

Lake Sediments ◽

Turnover Rates ◽

Hydrogenotrophic Methanogenesis ◽

Ch4 Production ◽

Relative Contribution ◽

Acetate Methyl ◽

Syntrophic Oxidation ◽

Aceticlastic Methanogenesis ◽

Respiratory Index ◽

Amazonian Lake

Abstract. Lake sediments in Amazonia are a significant source of CH4, a potential greenhouse gas. Previous studies of sediments using 13C analysis found that the contribution of hydrogenotrophic versus aceticlastic methanogenesis to CH4 production was relatively high. Here, we determined the methanogenic pathway in the same sediments (n = 6) by applying [14C]bicarbonate or [2-14C]acetate, and confirmed the high relative contribution (50–80 %) of hydrogenotrophic methanogenesis. The respiratory index (RI) of [2-14C]acetate, which is 14CO2 relative to 14CH4 &plus; 14CO2, divided the sediments into two categories, i.e., those with an RI 0.4 showing that a large percentage of the acetate-methyl was oxidized to CO2 rather than reduced to CH4. Hence, part of the acetate was probably converted to CO2 plus H2 via syntrophic oxidation, thus enhancing hydrogenotrophic methanogenesis. This happened despite the presence of potentially aceticlastic Methanosaetaceae in all the sediments. Alternatively, acetate may have been oxidized with a constituent of the sediment organic matter (humic acid) serving as oxidant. Indeed, apparent acetate turnover rates were larger than CH4 production rates except in those sediments with a R

Download Full-text

Methane Generation via Two-Phase Anaerobic Digestion of Organic Fraction of Municipal Solid Wastes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1051.317 ◽

2014 ◽

Vol 1051 ◽

pp. 317-321

Author(s):

Marjorie Baynosa ◽

Gladys Anne Bondoc ◽

Leandro Angelo Miguel Sanchez ◽

Analiza Rollon

Keyword(s):

Anaerobic Digestion ◽

Solid Waste ◽

Solid Wastes ◽

Small Scale ◽

Organic Fraction ◽

Municipal Solid Wastes ◽

Two Phase ◽

Methane Generation ◽

Solids Retention ◽

Useful Heat

The performance of a small-scale two-phase anaerobic digestion system which processes municipal solid wastes, i.e. vegetable and fruit wastes, was evaluated at mesophilic conditions. An anaerobic digester which required 5 L of fresh cow manure, 5 L of solid waste feed, 5 L each of leachate from the solid waste, and 1 L of anaerobic seeding had been constructed. The volume of the feed solids after digestion has significantly reduced after the operation. The total accumulated methane for a solids retention time (SRT) of 20 days contained useful heat energy amounting to 330.27 KJ.

Download Full-text

CLEAN UTILIZATION OF MUNICIPAL SOLID WASTES AND ALTERNATIVE FUELS DERIVED FROM IT

Environmental Problems ◽

10.23939/ep2020.04.202 ◽

2020 ◽

Vol 5 (4) ◽

pp. 202-209

Author(s):

Alexander Topal ◽

◽

Iryna Holenko ◽

Luidmyla Haponych ◽

◽

...

Keyword(s):

Thermal Treatment ◽

Municipal Solid Waste ◽

Solid Waste ◽

Alternative Fuels ◽

Solid Wastes ◽

Municipal Solid Wastes ◽

Local Conditions ◽

Ecological Requirements ◽

Clean Technologies

For the municipal solid waste (MSW) to be used in a proper way, it is necessary to implement clean technologies capable of thermal treatment of MSW and RDF in order to produce heat and electricity while meeting current ecological requirements. Nowadays, a number of technologies for MSW/RDF thermal treating are being used worldwide. Among them, the most proven technologies, applicable for industrial introduction, have been considered while analyzing their advantages/ disadvantages accounting for local conditions of Ukraine.

Download Full-text

Conditioning of oily sludges with municipal solid wastes incinerator fly ash

Water Science & Technology ◽

10.2166/wst.1997.0318 ◽

1997 ◽

Vol 35 (8) ◽

pp. 231-238 ◽

Cited By ~ 7

Author(s):

Tay Joo Hwa ◽

S. Jeyaseelan

Keyword(s):

Heavy Metals ◽

Fly Ash ◽

Specific Resistance ◽

Sewage Treatment ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

Solid Wastes ◽

Municipal Solid Wastes ◽

Capillary Suction ◽

Optimum Dosage

Conditioning of sludges improves dewatering characteristics and reduces the quantity of sludge to be handled. Anaerobic digested sludge collected from a sewage treatment plant contained 1.8% to 8% oil. The increase of specific resistance and capillary suction time (CST) with increasing oil content observed in these samples indicates the interference of oil in dewatering. It has been found that addition of municipal solid wastes incinerator fly ash decreases the specific resistances and capillary suction times of oily sludges rapidly up to 3% dosage. Beyond 3% fly ash, the decrease is less significant and the solids content in the sludge cake increases. This optimum dosage remains the same for sludges with varying oil contents from 1.8% to 12%. The total suspended solids of filtrate decreases with fly ash dosage but the toxic concentrations of heavy metals increases considerably. However at the optimum dosage of 3%, concentrations of heavy metals are within the limits for discharging into the sewers. The correlations of CST with the dewatering characteristics such as specific resistance, filter yield and corrected filter yield are established. These correlations can be used to obtain a quick prediction on dewaterability.

Download Full-text

Management of sewage sludge and municipal solid wastes directed toward zero emission.

ENVIRONMENTAL SYSTEMS RESEARCH ◽

10.2208/proer1988.27.365 ◽

1999 ◽

Vol 27 ◽

pp. 365-374 ◽

Cited By ~ 2

Author(s):

Rokuta INABA ◽

Keisuke HANAKI

Keyword(s):

Sewage Sludge ◽

Solid Wastes ◽

Municipal Solid Wastes ◽

Zero Emission

Download Full-text

Occurrence, geochemical fraction, ecological and health risk assessment of cadmium, copper and nickel in soils contaminated with municipal solid wastes

Chemosphere ◽

10.1016/j.chemosphere.2021.129573 ◽

2021 ◽

pp. 129573

Author(s):

Nihal Gujre ◽

Latha Rangan ◽

Sudip Mitra

Keyword(s):

Risk Assessment ◽

Health Risk ◽

Health Risk Assessment ◽

Solid Wastes ◽

Municipal Solid Wastes

Download Full-text

Municipal Solid Waste Characterization and Landfill Gas Generation in Kakia Landfill, Makkah

Sustainability ◽

10.3390/su13031462 ◽

2021 ◽

Vol 13 (3) ◽

pp. 1462

Author(s):

Faisal A. Osra ◽

Huseyin Kurtulus Ozcan ◽

Jaber S. Alzahrani ◽

Mohammad S. Alsoufi

Keyword(s):

Solid Waste ◽

Energy Recovery ◽

Solid Waste Management ◽

Landfill Gas ◽

Drainage System ◽

Solid Wastes ◽

Generation Model ◽

Gas Generation ◽

Municipal Solid Wastes ◽

Makkah City

In many countries, open dumping is considered the simplest, cheapest, and most cost-effective way of managing solid wastes. Thus, in underdeveloped economies, Municipal Solid Wastes (MSW) are openly dumped. Improper waste disposal causes air, water, and soil pollution, impairing soil permeability and blockage of the drainage system. Solid Waste Management (SWM) can be enhanced by operating a well-engineered site with the capacity to reduce, reuse, and recover MSW. Makkah city is one of the holiest cities in the world. It harbors a dozen of holy places. Millions of people across the globe visit the place every year to perform Hajj, Umrah, and tourism. In the present study, MSW characterization and energy recovery from MSW of Makkah was determined. The average composition of solid waste in Makkah city is organic matter (48%), plastics (25%), paper and cardboard (20%), metals (4%), glass (2%), textiles (1%), and wood (1%). In order to evaluate energy recovery potential from solid waste in Kakia open dumpsite landfill, the Gas Generation Model (LandGEM) was used. According to LandGEM results, landfill gas (methane and carbon dioxide) generation potential and capacity were determined. Kakia open dump has a methane potential of 83.52 m3 per ton of waste.

Download Full-text