Evaluation of alkalinity spatial distribution in an up-flow fixed bed anaerobic digester

2017 ◽  
Vol 77 (4) ◽  
pp. 948-959 ◽  
Author(s):  
Maha Hmissi ◽  
Jérôme Harmand ◽  
Victor Alcaraz-Gonzalez ◽  
Hedi Shayeb
Keyword(s):  
Experimental Data ◽  
Experimental Study ◽  
Spatial Distribution ◽  
Volatile Fatty Acids ◽  
Fixed Bed ◽  
Control Process ◽  
Fixed Bed Reactor ◽  
Hydrodynamic Behavior ◽  
Sampling Points ◽  
Tequila Vinasses

Abstract In this paper, an experimental study upon alkalinity and hydrodynamic behavior in an anaerobic up-flow fixed bed reactor for the treatment of tequila vinasses is presented. Measurements of volatile fatty acids, pH, alkalinity and bicarbonate were obtained at three sampling points in the reactor in the axial axis. Then, the spatial distribution of alkalinity is studied and discussed. Moreover, for further control process purposes, a hydrodynamic model based on the use of two interconnected two-steps reduced AM2 type models is proposed and its parameters are identified using experimental data.

Characteristics of Gaseous Produced from Co-Pyrolysis of Municipal Solid Waste and Corn Stalk

2014 ◽  
Vol 1010-1012 ◽  
pp. 947-951
Author(s):  
Jin Wei Jia ◽  
Ming Yuan Lu ◽  
Yue Fu Yuan ◽  
Lu Liu ◽  
Feng Sheng Yang ◽  
...  
Keyword(s):  
Experimental Study ◽  
Municipal Solid Waste ◽  
Solid Waste ◽  
Atmospheric Pressure ◽  
Fixed Bed ◽  
Pyrolysis Product ◽  
Fixed Bed Reactor ◽  
Corn Stalk ◽  
Product Yields ◽  
Gaseous Products

An experimental study on co-pyrolysis of municipal solid waste and corn stalk was performed in a fixed-bed reactor under atmospheric pressure. The effect of different blending ratio on the pyrolysis product yields and compositions of the gaseous products was investigated. The results indicated that there exist synergetic effects in the co-pyrolysis of municipal solid waste and corn stalk. Under the different blending ratio conditions, the char and liquid yields were lower than the theoretical values calculated on pyrolysis of each individual municipal solid waste and corn stalk, and consequently the gas yields were higher. H2 and CH4 obtained co-pyrolysis at 800°C-900°C of 40% blending ratio conditions were higher than those of municipal solid waste and corn stalk alone.

Experimental Study on Biomass Char Combustion in O2/CO2 Atmosphere

2014 ◽  
Vol 694 ◽  
pp. 136-141 ◽  
Author(s):  
Jing Hong Lian ◽  
Zi Fang Wang ◽  
Wei Ji ◽  
Guang Yang ◽  
Lian Sheng Liu ◽  
...  
Keyword(s):  
Experimental Study ◽  
Fixed Bed ◽  
Reactor System ◽  
Fixed Bed Reactor ◽  
No Emission ◽  
Char Combustion ◽  
Biomass Char

Experiments of biomass char combustion in 10%O2/90%CO2, 21%O2/79%CO2, 10%O2/90%N2 and 21%O2/79%N2 atmospheres were performed in the fixed-bed reactor system at the temperature of 800°C-1200°C. The results show that at the same temperature, NO emission is higher in O2/N2 atmosphere than that in O2/CO2 atmosphere. The higher the O2 concentration is, the higher the NO yield is. As the temperature rises, the NO yield rises at first and then decreases at the same O2 concentration and atmosphere.

Anaerobic digestion of deproteinated cheese whey

1985 ◽  
Vol 52 (3) ◽  
pp. 457-467 ◽  
Author(s):  
Johannes De Haast ◽  
Trevor J. Britz ◽  
Johannes C. Novello ◽  
Emilige W. Verwey
Keyword(s):  
Volatile Fatty Acids ◽  
Biogas Production ◽  
Fixed Bed ◽  
Oxygen Demand ◽  
Ammonia Level ◽  
Fixed Bed Reactor ◽  
Total Carbon ◽  
Ammonia Toxicity ◽  
Biogas Yield ◽  
Titration Curves

SUMMARYWhey and deproteinated whey preparations with different carbon: nitrogen (C/N) ratios ranging from 7·5 to 73 were digested anaerobically in a downflow stationary fixed-bed reactor at 35 °C with a hydraulic retention time of 5 d. Effluent and biogas parameters indicated that no decrease in digestion and stability occurred at the highest C/N ratio. Chemical oxygen demand (COD) removal averaged 88%, while volatile fatty acids were maintained at a low level (< 500 mg l–1). Biogas yield averaged 0·423 m3kg–1COD and the methane content of the biogas varied between 57 and 63%. Ammonia toxicity occurred at a C/N ratio of 7/5 in the substrate feed. Virtually no ammonia N was detected in the effluent when whey substrates with C/N ratios of 50 and 73 were fed. Titration curves showed that buffer intensities in the effluent were not affected by a decrease in ammonia level. A decrease in the biomass content of the effluent which occurred as a result of the increase in C/N ratio of the substrate did not cause any rate limiting effect on biogas production. The removal of protein from the whey caused a reduction in the ratio of COD: total carbon in the whey. On average 59% of the carbon in the substrate was converted to biogas.

scholarly journals Synthesis of methanol in microchnnel

2021 ◽  
Vol 2119 (1) ◽  
pp. 012113
Author(s):  
S V Dimov
Keyword(s):  
Experimental Data ◽  
Carbon Monoxide ◽  
Chemical Reactions ◽  
Synthesis Gas ◽  
Methanol Synthesis ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Microchannel Reactor ◽  
Flow Rates ◽  
Synthesis Of Methanol

Abstract Systematic experimental data have been obtained on the results of catalytic chemical reactions in a microchannel reactor for the synthesis of methanol from synthesis gas. Synthesis gas contains hydrogen, carbon monoxide and dioxide, as well as nitrogen in the ratio 58/29/5/8. The experiments were carried out at different flow rates in the temperature range 190-260C. Experiments were also carried out for methanol synthesis in fixed bed reactor at different synthesis pressures.

Production and Utilization of Volatile Fatty Acids in Various Types of Anaerobic Reactors

1985 ◽  
Vol 17 (1) ◽  
pp. 191-205 ◽  
Author(s):  
M Dohányos ◽  
B Kosová ◽  
J Zábranská ◽  
P Grau
Keyword(s):  
Fatty Acids ◽  
Volatile Fatty Acids ◽  
Biogas Production ◽  
Fixed Bed ◽  
Caproic Acid ◽  
Fixed Bed Reactor ◽  
Production Volume ◽  
Anaerobic Reactors ◽  
Volumetric Rate ◽  
Volumetric Loading

Production and subsequent utilization of fatty acids (from C2 to C6) was followed in three types of anaerobic reactors:uplow sludge bed reactor (USBR),upflow fixed bed reactor (UFBR),downflow fixed bed reactor (DFBR). It was found that the concentrations of lower fatty acids increased exponentially with increasing volumetric loading of the reactor in the range up to 15 kg m−3d−1 (as COD). Up to a loading of about 4 kg m−3d−1, only acetic and propionic acids appeared. Butyric and valeric acids were found only at a loading higher than 4 kg m−3d−1, caproic acid at a loading higher than 8 kg m−3d−1. The highest removal rates along the reactor were observed for butyric acid, the lowest for propionic acid. The volumetric rate of biogas production (volume of gas per volume of reactor per time) increased with increasing loading rates up to 4.6 m3m−3d−1. The UFBR was in general less sensitive to inhibition by fatty acids and to lower temperatures and fluctuation of loads than the other two types of reactors.

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