scholarly journals Thermal Decomposition and Combustion of Microwave Pre-Treated Biomass Pellets

Processes ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 492
Author(s):  
Linards Goldšteins ◽  
Raimonds Valdmanis ◽  
Maija Zaķe ◽  
Alexandr Arshanitsa ◽  
Anna Andersone
Keyword(s):  
Thermal Decomposition ◽  
Wheat Straw ◽  
Elemental Composition ◽  
Heat Production ◽  
Flame Temperature ◽  
Combustion Efficiency ◽  
Heat Output ◽  
Structural Variations ◽  
Microwave Pretreatment ◽  
Pretreated Wheat Straw

The objective of the study was to investigate a more effective use of commercially available biomass pellets (wheat straw, wood, peat) using microwave pretreatment to improve heat production. Pellets were pretreated using the originally designed microwave torrefaction device. The effects of microwave (mw) pretreatment were quantified, providing measurements of the weight loss and elemental composition of pellets and estimating the effect of mw pretreatment on their porosity, surface area and calorific values at pretreatment temperatures of T = 448–553 K. Obtained results show that the highest structural variations and elemental composition during mw pretreatment were obtained for wheat straw pellets, with an increase in reactivity, a decreasing in the duration of the thermal decomposition by about 40% and an increase in the yield of combustible volatiles. Increased reactivity of pretreated pellets enhanced the ignition and burnout of volatiles, decreasing the duration of the burnout of pretreated wheat straw, wood and peat pellets by 40%, 24% and 9%, respectively, and increasing the peak and average values of the flame temperature, heat output, and produced heat energy by 40–50%, with a correlating increase of combustion efficiency and the mass fraction of carbon-neutral CO2 emission. Thus, the applicability of microwave pretreatment for the control and improvement of heat production was confirmed.

scholarly journals Electric Field Effect on the Thermal Decomposition and Co-combustion of Straw with Solid Fuel Pellets

Energies ◽  
2019 ◽  
Vol 12 (8) ◽  
pp. 1522 ◽  
Author(s):  
Inesa Barmina ◽  
Antons Kolmickovs ◽  
Raimonds Valdmanis ◽  
Maija Zake ◽  
Sergejs Vostrikovs ◽  
...  
Keyword(s):  
Electric Field ◽  
Solid Fuel ◽  
Flame Temperature ◽  
Fixed Bed ◽  
Chemical Conversion ◽  
Combustion Efficiency ◽  
Combustion Characteristics ◽  
Heat Output ◽  
Electric Field Effect ◽  
Fuel Mixtures

The aim of this study was to provide more effective use of straw for energy production by co-firing wheat straw pellets with solid fuels (wood, peat pellets) under additional electric control of the combustion characteristics at thermo-chemical conversion of fuel mixtures. Effects of the DC electric field on the main combustion characteristics were studied experimentally using a fixed-bed experimental setup with a heat output up to 4 kW. An axisymmetric electric field was applied to the flame base between the positively charged electrode and the grounded wall of the combustion chamber. The experimental study includes local measurements of the composition of the gasification gas, flame temperature, heat output, combustion efficiency and of the composition of the flue gas considering the variation of the bias voltage of the electrode. A mathematical model of the field-induced thermo-chemical conversion of combustible volatiles has been built using MATLAB. The results confirm that the electric field-induced processes of heat and mass transfer allow to control and improve the main combustion characteristics thus enhancing the fuel burnout and increasing the heat output from the device up to 14% and the produced heat per mass of burned solid fuel up to 7%.

scholarly journals Experimental Study of Thermal Decomposition and Combustion of Lignocellulosic Biomass Pellets / GRANULĒTAS LIGNOCELULOZES BIOMASAS TERMISKĀS SADALĪŠANĀS UN DEGŠANAS PROCESU EKSPERIMENTĀLIE PĒTĪJUMI

2013 ◽  
Vol 50 (3) ◽  
pp. 35-48 ◽  
Author(s):  
I. Barmina ◽  
A. Lickrastina ◽  
M. Zake ◽  
A. Arshanitsa ◽  
V. Solodovnik ◽  
...  
Keyword(s):  
Experimental Study ◽  
Thermal Decomposition ◽  
Wheat Straw ◽  
Lignocellulosic Biomass ◽  
Energy Production ◽  
Flame Temperature ◽  
Heat Energy ◽  
Combustion Characteristics ◽  
Biomass Composition ◽  
Thermochemical Conversion

The study is aimed at cleaner and more efficient heat energy production through investigation and analysis of the thermal decomposition of lignocellulosic biomass pellets with different elemental composition, the heating values and contents of hemicellulose, cellulose and lignin. The estimation is provided for the influence of biomass composition on the combustion characteristics for softwood, wheat straw and wheat straw lignin pellets. The kinetics of thermal decomposition was studied experimentally, using a pilot device for two-stage processes of thermochemical conversion including gasification and combustion of biomass pellets under varying conditions. The experimental study includes time-dependent measurements of the biomass pellet weight loss during gasification and the correlating variations of the flame temperature, heat production rates, combustion efficiency and composition of the products at different stages of thermochemical conversion. Estimation is also given for the influence of the biomass composition on the combustion characteristics and heat energy production.

Glucose and xylose co-fermentation of pretreated wheat straw using mutants of S. cerevisiae TMB3400

2013 ◽  
Vol 164 (1) ◽  
pp. 50-58 ◽  
Author(s):  
Borbála Erdei ◽  
Balázs Frankó ◽  
Mats Galbe ◽  
Guido Zacchi
Keyword(s):  
Wheat Straw ◽  
Pretreated Wheat Straw

scholarly journals No major thermogenic role for (Na+ + K+)-dependent adenosine triphosphatase apparent in hepatocytes from hyperthyroid rats

1982 ◽  
Vol 202 (3) ◽  
pp. 661-665 ◽  
Author(s):  
D G Clark ◽  
M Brinkman ◽  
O H Filsell ◽  
S J Lewis ◽  
M N Berry
Keyword(s):  
Oxygen Consumption ◽  
Oxygen Uptake ◽  
Atpase Activity ◽  
Heat Production ◽  
Adenosine Triphosphatase ◽  
Heat Output ◽  
Liver Parenchymal ◽  
Dependent Atpase ◽  
Parenchymal Cells ◽  
Isolated Liver

(Na+ + K+)-dependent ATPase activity, heat production and oxygen consumption were increased by 59%, 62% and 75% respectively in hepatocytes from tri-iodothyronine-treated rats. Ouabain at concentrations of 1 and 10 mM decreased oxygen uptake by 2-8% in hepatocytes from euthyroid rats and by 5-15% in hepatocytes from hyperthyroid animals. Heat output was decreased by 4-9% with the glycoside in isolated liver parenchymal cells from the control animals and by 11% in the cells from the tri-iodothyronine-treated animals. These results do not support the hypothesis that hepatic (Na+ + K+)-ATPase plays a major role in increased heat production in hepatocytes from hyperthyroid rats.

scholarly journals Alkali treatment of fungal pretreated wheat straw for bioethanol production

Bioethanol ◽  
2016 ◽  
Vol 2 (1) ◽  
Author(s):  
María García-Torreiro ◽  
Miguel Álvarez Pallín ◽  
María López-Abelairas ◽  
Thelmo A. Lu-Chau ◽  
Juan M. Lema
Keyword(s):  
Wheat Straw ◽  
Alkali Treatment ◽  
Alkaline Treatment ◽  
White Rot ◽  
White Rot Fungus ◽  
Process Conditions ◽  
Alkali Pretreatment ◽  
Irpex Lacteus ◽  
C 30 ◽  
Pretreated Wheat Straw

AbstractBioconversion of lignocellulosic materials into ethanol requires an intermediate pretreatment step for conditioning biomass. Sugar yields from wheat straw were previously improved by the addition of a mild alkali pretreatment step before bioconversion by the white-rot fungus Irpex lacteus. In this work, an alternative alkaline treatment, which significantly reduces water consumption, was implemented and optimized. Sugar recovery increased 117% with respect to the previously developed alkaline wash process at optimal process conditions (30°C, 30 minutes and 35.7% (w/w) of NaOH). In order to further reduce operational costs, a system for alkali recycling was implemented. This resulted in the treatment of 150% more wheat straw using the same amount of NaOH. Finally, enzymatic hydrolysis was optimized and resulted in a reduction of enzyme dose of 33%.

The contribution of nitrate respiration to the energy budget of the symbiont-containing clam Lucinoma aequizonata: a calorimetric study

1996 ◽  
Vol 199 (2) ◽  
pp. 427-433
Author(s):  
U Hentschel ◽  
S Hand ◽  
H Felbeck
Keyword(s):  
Heat Production ◽  
Sea Water ◽  
Anaerobic Respiration ◽  
Gill Tissue ◽  
Nitrate Respiration ◽  
Heat Output ◽  
Marine Bivalve ◽  
Calorimetric Study ◽  
Perfusion Medium ◽  
Terminal Electron Acceptor

Heat production and nitrate respiration rates were measured simultaneously in the gill tissue of Lucinoma aequizonata. This marine bivalve contains chemoautotrophic, intracellular, bacterial symbionts in its gill tissue. The symbionts show constitutive anaerobic respiration, using nitrate instead of oxygen as a terminal electron acceptor. An immediate increase in heat production was observed after the addition of nitrate to the perfusion medium of the calorimeter and this was accompanied by the appearance of nitrite in the effluent sea water. The nitrate-stimulated heat output was similar under aerobic and anaerobic conditions, which is consistent with the constitutive nature of nitrate respiration. The amount of heat released was dependent on the concentration of nitrate in the perfusion medium. At nitrate concentrations between 0.5 and 5 mmol l-1, the total heat production was increased over twofold relative to unstimulated baseline values. A mean (±s.e.m.) experimental enthalpy of -130±22.6 kJ mol-1 nitrite (N=13) was measured for this concentration range.

Methane recovery from anaerobic digestion of urea-pretreated wheat straw

2018 ◽  
Vol 115 ◽  
pp. 139-148 ◽  
Author(s):  
Yiqing Yao ◽  
Andre David Bergeron ◽  
Maryam Davaritouchaee
Keyword(s):  
Anaerobic Digestion ◽  
Wheat Straw ◽  
Methane Recovery ◽  
Pretreated Wheat Straw

scholarly journals Microcalorimetric measurements of heat production in brown adipocytes from control and cafeteria-fed rats

1986 ◽  
Vol 235 (2) ◽  
pp. 337-342 ◽  
Author(s):  
D G Clark ◽  
M Brinkman ◽  
S D Neville
Keyword(s):  
Oleic Acid ◽  
Heat Production ◽  
Oxidative Metabolism ◽  
Heat Output ◽  
O2 Consumption ◽  
O2 Uptake ◽  
Average Volume ◽  
Brown Adipocytes ◽  
Chemical Agents ◽  
Sequential Addition

The effects of the sequential addition of glucose, noradrenaline, propranolol and oleic acid on the rates of O2 consumption and heat production by isolated interscapular brown adipocytes from control and cafeteria-fed rats were compared. Although the chemical agents produced very similar changes in oxidative metabolism, the actual rates of O2 uptake and heat output in adipocytes from the cafeteria-fed rats, when expressed per g dry wt. of cells, were approx. 65% less than those obtained with cells from the control rats. However, when the same results were expressed per 10(8) multiloccular brown adipocytes, rather than gravimetrically, rates of O2 consumption and heat production were equivalent. Further interpretation of these data is complicated, because the average volume of multiloccular brown adipocytes from cafeteria-fed rats was 2.5 times that for multiloccular cells from control animals.

scholarly journals Metals and Alloys Additives as Enhancer for Rocket Propulsion: A Review

2021 ◽  
Vol 90 (1) ◽  
pp. 1-9
Author(s):  
Izham Izzat Ismail ◽  
Norhuda Hidayah Nordin ◽  
Muhammad Hanafi Azami ◽  
Nur Azam Abdullah
Keyword(s):  
Specific Impulse ◽  
Flame Temperature ◽  
High Energy ◽  
Combustion Efficiency ◽  
High Energy Density ◽  
Regression Rate ◽  
High Entropy ◽  
Rocket Propulsion ◽  
Wide Range ◽  
Metal Additives

A rocket's engine usually uses fuel and oxygen as propellants to increase the rocket's projection during launch. Nowadays, metallic ingredients are commonly used in the rocket’s operation to increase its performance. Metallic ingredients have a high energy density, flame temperature, and regression rate that are important factors in the propulsion process. There is a wide range of additives have been reported so far as catalysts for rocket propulsion. The studies show that the presence of metal additives improves the regression rate, specific impulse and combustion efficiency. Herein, the common energetic additives for rocket propulsion such as metal and light metals are reviewed. Besides the effect of these energetic particles on the regression behaviors of base (hybrid) fuel has been exclusively discussed. This paper also proposed a new alloy namely high entropy alloys (HEAs) as a new energetic additive that can potentially increase the performance of the rocket propellant system.

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