Experimental Study on Combustion Characteristics of Three Biomass Components

2014 ◽  
Vol 953-954 ◽  
pp. 309-312
Author(s):  
Gui Qiu Su ◽  
Jian Yang ◽  
Hong Bo Lu
Keyword(s):  
Experimental Study ◽  
Weight Loss ◽  
High Temperature ◽  
Low Temperature ◽  
Combustion Process ◽  
Combustion Characteristics ◽  
Heating Rates ◽  
Biomass Components ◽  
Coke Combustion ◽  
Obvious Weight Loss

Experiments on combustion characteristics of cellulose, xylan and lignin have been done conducted on Pyris1 TGA thermograyimetric analyzer (PE/USA) at different heating rates. The results show that: combustion of cellulose was mainly concentrated in a low temperature range, xylan has two obvious weight loss peaks, while the lignin combustion mainly concentrated in a high temperature coke combustion process.

Study on Co-Combustion of Oil Shale Semi-Coke and Corn Stalk

2012 ◽  
Vol 614-615 ◽  
pp. 103-106
Author(s):  
Hong Peng Liu ◽  
Wei Yi Li ◽  
Xu Dong Wang ◽  
Hao Xu ◽  
Guan Yi Chen ◽  
...  
Keyword(s):  
Activation Energy ◽  
High Temperature ◽  
Low Temperature ◽  
Oil Shale ◽  
Combustion Process ◽  
Combustion Characteristics ◽  
Corn Stalk ◽  
Kinetics Parameters ◽  
High Temperature Stage ◽  
Blend Ratios

Co-combustion experiment of oil shale semi-coke and corn stalk at different blend ratios was performed using thermogravimetric analyzer. The influence of different blend ratios has been studied. The combustion characteristics are obtained under the heating rates of 20oC/min and the experimental temperature range of 40-850oC. The combustion process of the blends is divided into three stages: low-temperature stage, transition stage and high-temperature stage. With the increasing of corn stalk in the blends, the reaction of combustion mainly shifts from high-temperature stage to low-temperature stage, and there is no obvious change for the ignition temperature, but the burn out temperature comes down. The combustion kinetics parameters of the blends were analyzed using Flynn-Wall-Ozawa model. The result shows that the activation energy of the volatile matter stage increases and the activation energy of semi-coke combustion stage decreases. The combustion characteristics of the oil shale semi-coke get improved significantly with the mixture of corn stalk.

Study of high-pressure air jet controlled compression ignition with compound thermodynamic cycle for combustion and emission formation process

2020 ◽  
pp. 146808742096933
Author(s):  
Xiangyu Meng ◽  
Sicheng Liu ◽  
Jingchen Cui ◽  
Jiangping Tian ◽  
Wuqiang Long ◽  
...  
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Low Temperature ◽  
Formation Process ◽  
Combustion Process ◽  
Thermodynamic Cycle ◽  
Compression Ignition ◽  
Temperature Reaction ◽  
Air Jet ◽  
High Temperature Reaction

A novel method called high-pressure air (HPA) jet controlled compression ignition (JCCI) based on the compound thermodynamic cycle was investigated in this work. The combustion process of premixed mixture can be controlled flexibly by the high-pressure air jet compression, and it characterizes the intensified low-temperature reaction and two-stage high-temperature reaction. The three-dimensional (3D) computational fluid dynamics (CFD) numerical simulation was employed to study the emission formation process and mechanism, and the effects of high-pressure air jet temperature and duration on emissions were also investigated. The simulation results showed that the NOx formation is mainly affected by the first-stage high-temperature reaction due to the higher reaction temperature. Overall, this combustion mode can obtain ultra-low NOx emission. The second-stage high-temperature reaction plays an important role in the CO and THC formation caused by the mixing effect of the high-pressure air and original in-cylinder mixture. The increasing air jet temperature leads to a larger high-temperature in-cylinder region and more fuel in the first-stage reaction, and therefore resulting in higher NOx emission. However, the increasing air jet temperature can significantly reduce the CO and THC emissions. For the air jet duration comparisons, both too short and too long air jet durations could induce higher NOx emission. A higher air jet duration would result in higher CO emission due to the more high-pressure air jet with relatively low temperature.

Experimental Study on Combustion Characteristics of Biomass and Coal Blended

2013 ◽  
Vol 805-806 ◽  
pp. 200-207
Author(s):  
Bing Zhang ◽  
Guang Wu Lu
Keyword(s):  
Particle Size ◽  
Ignition Temperature ◽  
Combustion Process ◽  
Combustion Characteristics ◽  
Combustion Characteristic ◽  
Thermogravimetric Analyzer ◽  
Rate Of Combustion ◽  
Mixing Proportion ◽  
Biomass Particle Size ◽  
Obvious Weight Loss

Under different conditions,combustion characteristics of the single biomass,the single coal and the mixture of biomass and coal were analyzed by using thermogravimetric analyzer. Combustion characteristic parameters of the sawdust,the rice husk,the rice straw and the Baisha coal of Leiyang were studied,including ignition temperature,the maximum rate of combustion temperature,the burnout temperature and so on. The experimental results show that the biomass burning temperature is lower than the Baisha coal and there are two obvious weight loss phases in the combustion process of the biomass. However,there is only one in the coal. The ignition temperature and time of the coal can be reduced ,the temperature range of the entire combustion can be extended,the coal can be burnout more well and the fuel combustion characteristic can be optimized by blending combustion. With the increase of biomass mixing proportion, the ignition temperature of mixing samples was decreased more obviously. Moreover,when the biomass particle size becomes R200,compared with R90 particle size under the same blending ratio,its ignition temperature is more lower.

Pyrolysis Characteristics of Pine Powder and Polyvinyl Chloride of Municipal Solid Waste in Thermogravimetric Analyzer

2013 ◽  
Vol 781-784 ◽  
pp. 2009-2012 ◽  
Author(s):  
Hai Yu Meng ◽  
Shu Zhong Wang ◽  
Lin Chen ◽  
Jun Zhao ◽  
Zhi Qiang Wu
Keyword(s):  
Weight Loss ◽  
Municipal Solid Waste ◽  
Solid Waste ◽  
Heating Rate ◽  
Polyvinyl Chloride ◽  
Heating Rates ◽  
Pyrolysis Characteristics ◽  
Thermogravimetric Analyzer ◽  
Tg And Dtg ◽  
Obvious Weight Loss

The pyrolysis characteristics of pine powder and polyvinyl chloride (PVC), respectively representing the biomass and plastics components of municipal solid waste, were studied in a thermogravimetric analyzer, and the influence of heating rate on pyrolysis characteristics was also investigated. The pyrolysis temperature was heated from ambient up to 900 °C at different heating rates including 10, 20 and 40 °Cžmin-1. The pyrolysis of pine powder was composed of two obvious weight loss phases, which were dehydration and the decomposition of cellulose and hemicellulose. The lignin in pine powder decomposed over a broad temperature range until 900°C. The pyrolysis of PVC was complicated, and included the release of hydrogen chloride (HCl), the formation of hydrocarbons. Besides, the additives in PVC decomposed at about 600 °C. The TG and DTG curves of pyrolysis for pine powder and PVC were similar at different heating rates, however, each weight loss phase of pyrolysis was shifted to high temperature with increasing the heating rate.

scholarly journals Producing Effective and Clean Coke for Household Combustion Activities to Reduce Gaseous Pollutant Emissions

2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Shoujun Liu ◽  
Ju Shangguan ◽  
Song Yang ◽  
Wenguang Du ◽  
Xudong Yan ◽  
...  
Keyword(s):  
High Temperature ◽  
Combustion Process ◽  
Pollutant Emissions ◽  
Atmospheric Environment ◽  
Gaseous Pollutant ◽  
New Type ◽  
Coke Combustion ◽  
Household Activities ◽  
Sulfur And Nitrogen Compounds ◽  
Sulfur Fixation

Nowadays, the gaseous pollutant emissions, including particulate matter (PM), sulfur dioxide (SO2), and nitrogen oxide (NOx) from household coal combustion, cause great threat to environment and public health by contributing to severe haze in China. Particularly, a clean coke free of the major pollutants precursors (sulfur and nitrogen compounds) by sulfur fixation and denitrification has been deemed as an effective strategy to reducing pollutants. In this paper, a preprocessed coke was prepared by co-pyrolysis of high-sulfur coal with the assistance of calcium-based and iron-based complexes at high temperature. The results show that high-temperature co-pyrolysis could remove the volatile compounds that are major precursors for the formation of gaseous pollutants from the raw coal. During the coking process, the sulfur can be removed by being fixed in the form of CaS in presence of a Ca-based complex, which could be beneficial for the CaSO4 during the coke combustion. The volatile nitrogen is transferred to the gas phase with the addition of Fe-based complexes, which effectively reduce the residual nitrogen in coke. As a result, Ca-based additives captured the released SO2 and formed CaSO4 during the combustion process. In addition, in the presence of Fe-based complexes, both char and CO react with NOx to form N2, which leads to a reduction in NOx emissions during combustion. Additionally, the replacement of current residential coal with a new type of clean coke is a facile method for reducing gaseous pollutant emissions from household activities to protect the atmospheric environment. The average emission factors (EFs) of PM, SO2, and NOx for the prepared clean coke were small during combustion and were much lower than the EFs of the tested raw coal, semicoke, and briquettes.

scholarly journals The Formation of the Oxides of Carbon by the Pyrolysis of Tobacco

1975 ◽  
Vol 8 (1) ◽  
Author(s):  
R. R. Baker
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
High Temperature ◽  
Low Temperature ◽  
Heating Rate ◽  
Temperature Region ◽  
High Temperature Region ◽  
Heating Rates ◽  
Carbon Oxides ◽  
Decomposition Reactions

AbstractFlue-cured Virginia tobacco has been heated in nitrogen and nitrogen/oxygen mixtures under flow conditions, and the rate of formation of carbon monoxide and carbon dioxide has been determined as a function of temperature, heating rate, and proportion of oxygen in the gas. When the tobacco is heated in nitrogen at heating rates comparable to those in a smouldering cigarette, 27 % of the carbon content of the tobacco is converted to carbon oxides. Both carbon oxides show two distinct formation regions: a low-temperature region (about 100°-450°C), and a high-temperature region (about 550°-900°C). These temperature limits are almost identical to those predicted from studies on the combustion coal of a cigarette burning in air. When tobacco, or the carbonaceous residue remaining after the pyrolysis experiments, is heated in nitrogen / oxygen mixtures, the total amount of carbon converted to carbon monoxide and carbon dioxide is independent of heating rate, but the relative proportions of the two oxides are strongly dependent on heating rate. At the lower heating rate, proportionally less carbon monoxide, and more carbon dioxide, is produced. Under oxidation conditions, about 70 % of both carbon oxides formed in the low-temperature region (100°-450°C) are produced by tobacco decomposition reactions, whereas in the high-temperature region about 10-20 % of the carbon monoxide, and 2-9 % of the carbon dioxide, are produced by tobacco decomposition.

Experiment Study on Mixed Combustion of Biomass and Coal

2014 ◽  
Vol 978 ◽  
pp. 3-6
Author(s):  
Ping Cai ◽  
Li Jun Zhao ◽  
Kun Wang ◽  
Song Tao Kong
Keyword(s):  
Combustion Temperature ◽  
Combustion Process ◽  
Calorific Value ◽  
Combustion Characteristics ◽  
Energy Resources ◽  
Performance Impact ◽  
Comprehensive Utilization ◽  
Temperature Combustion ◽  
Coke Combustion ◽  
Biomass Sample

Mixed combustion of biomass and coal is a new combustion way of comprehensive utilization biomass and coal energy resources. Biomass is more volatile, lower combustion temperature, combustion is mainly concentrated in front, low calorific value and the use of value is limited. Coal is less volatile, high combustion temperature, combustion exothermic are mainly concentrated in coke combustion, and exothermic is high. Studying on the combustion process and the combustion characteristics of mixed combustion of biomass and coal is development technologies based of mixed combustion of biomass and coal. Choose two biomass sample Sawdust, confetti and a coal, analyze combustion characteristics to mixing sample of different ratio, to obtain combustion process of mixed sample, combustion performance impact of biomass to coal and calorific influence of coal to biomass.

Non-isothermal thermogravimetric analysis of heavy oil in an O2/CO2 atmosphere

2018 ◽  
Vol 16 (6) ◽  
Author(s):  
Zhiqiang Wang ◽  
Ming Liu ◽  
Xingxing Cheng ◽  
Yusheng He ◽  
Yingjie Hu ◽  
...  
Keyword(s):  
Activation Energy ◽  
High Temperature ◽  
Thermogravimetric Analysis ◽  
Low Temperature ◽  
Oxygen Concentration ◽  
Heavy Oil ◽  
Combustion Process ◽  
Molecular Weights ◽  
Diffusion Controlled ◽  
Temperature Activation

Abstract Although heavy oil is an abundant and promising energy source, its processing and utilization are complicated due to its high density, low hydrogen/carbon ratio, and high asphaltene content. Fortunately, these problems can be mitigated by the application of oxy-fuel combustion. To gain deeper insights into the above technology, the characteristics of heavy oil combustion in an O2/CO2 atmosphere was investigated using non-isothermal thermogravimetric analysis. We demonstrate that the combustion process consisted of four stages. Low-molecular-weight hydrocarbons reacted at low temperature, whereas heavy ones required a higher temperature. Increasing the concentration of oxygen resulted in increased TGA and DSC peak intensities and decreased peak widths, and these peaks were shifted to lower temperatures. Coat-Redfern and Flynn-Wall-Ozzawa methods were used to evaluate the kinetic parameters (E, A) of the oxidation process, showing that the high-temperature activation energy was much higher than the low-temperature one due to the different molecular weights of the oxidized substrates in each region. The reaction was demonstrated to be diffusion-controlled, as reflected by the lower activation energy at high oxygen concentration and high temperature, with the influence of oxygen concentration on QO processes being much more obvious than that on SO ones.

An Experimental Study of Grease in Elastohydrodynamic Lubrication

1972 ◽  
Vol 94 (1) ◽  
pp. 27-34 ◽  
Author(s):  
S. Y. Poon
Keyword(s):  
Experimental Study ◽  
High Temperature ◽  
Low Temperature ◽  
Elastohydrodynamic Lubrication ◽  
Time Dependent ◽  
Base Oil ◽  
Mineral Oils ◽  
Lubricating Film ◽  
Dependent Behavior ◽  
Inlet Zone

The formation of a lubricating film by grease in conditions pertinent to elastohydrodynamic lubrication is studied in a disk machine, and the thickness measured by means of a magnetic reluctance technique. The greases examined are three lithium hydroxystearate greases, of different soap structures and soap contents, a low temperature sodium-based grease, and a high temperature clay-based grease, all in mineral oils. The film thickness of greases in EHL differs from that of pure mineral oils in one important aspect: with one charge of the lubricant the thickness decreases continuously with time. The time-dependent behavior of greases is examined in relation to the thickener structure, viscosity of the base oil, and the conditions of the inlet zone.

Sign in / Sign up

Export Citation Format

Share Document