scholarly journals Influence of Biochar Composition and Micro-Structure on the Denitration of Flue Gases at High Temperature

2020 ◽  
Vol 10 (6) ◽  
pp. 1920
Author(s):  
Yali Wang ◽  
Nannan Qin ◽  
Suping Cui ◽  
Xiaoyu Ma ◽  
Siyu Peng
Keyword(s):  
High Temperature ◽  
Functional Groups ◽  
Rice Husk Ash ◽  
No Reduction ◽  
Fixed Bed ◽  
Flue Gases ◽  
Composition And Structure ◽  
O2 Concentration ◽  
Denitration Rate ◽  
Positive Effect

Biochar materials are good reducers of nitrogen oxides. The composition and structure of biochar affect significantly its ability to reduce C–NO. In order to study the denitration of flue gases by biochar at high temperature, three kinds of biochar (bamboo charcoal (BC), rice husk ash (RHA), and straw charcoal (SC)) were mixed with cement raw meal in a fixed-bed quartz reactor at the temperature of 800–900 °C and O2 concentration of 0.5%–2%. The results showed that the initial denitration rate of BC was higher than that of RHA, and that of SC was the lowest. RHA had the largest specific surface area, and BC the smallest. The elements C, N, and O and the functional groups of the three types of biochar had a greater influence on the denitration rate than their structures. The denitration rate decreased faster as the O/C ratio increased, and the increase in the relative content of the N element induced the formation of nitrogen-containing functional groups catalyzing C–NO reduction. The content of the C–C bond affected directly the rate of denitration, and both (NCO)x and C–O bonds had a positive effect on the reduction capability of biochar. It can be concluded that the composition of biochar has an important effect on the reduction of C–NO.

Effect of Cement Raw Meal on the NO Reduction by Biomass Char

2020 ◽  
Vol 993 ◽  
pp. 1401-1406
Author(s):  
Nan Li ◽  
Su Ping Cui ◽  
Ya Li Wang ◽  
Xiao Yu Ma ◽  
Shi Jie Liu ◽  
...  
Keyword(s):  
High Temperature ◽  
No Reduction ◽  
Fixed Bed ◽  
Reduction Rate ◽  
Laboratory Scale ◽  
Carbon Surface ◽  
Long Time ◽  
Negative Effect ◽  
Biomass Char ◽  
Positive Effect

The influence of cement raw meal on the NO reduction by biomass char at a high temperature of 900 °C with four O2 concentrations of 1%, 3%, 5% and 8% was investigated in a laboratory scale fixed bed quartz reactor. The results showed that the cement raw meal had certain positive effect on NO reduction by biomass char which promotes dissociation adsorption of NO with the help of CO consumption and oxygen transferred to carbon surface, however, it also shows some negative effect, and the degree depends on O2 concentration. A long-time and high NO reduction rate was obtained in the case of 1% O2 concentration.

NO Reduction Using Coal and Active Carbon with and without Catalysts

2021 ◽  
Vol 1035 ◽  
pp. 1096-1101
Author(s):  
Nan Li ◽  
Ya Li Wang ◽  
Su Ping Cui
Keyword(s):  
Active Carbon ◽  
No Reduction ◽  
Fixed Bed ◽  
Reducing Agent ◽  
Fixed Bed Reactor ◽  
Significant Positive Effect ◽  
Temperature Dependent ◽  
Positive Effect ◽  
Better Than

Reducing NO using coal and active carbon with and without the addition of catalysts were investigated in a fixed bed reactor at a wide temperature of 250-850 °C. The results indicated that without the catalysts, NO reduction using coal was significantly better than that using active carbon. When coal was used as reducing agent, the addition of catalysts made the NO reduction occurred earlier and the effect of catalysts was temperature-dependent. When active carbon was used to reduce NO, the addition of catalysts was not ideal and only CuO showed a significant positive effect above 700 °C.

scholarly journals Desulfurization and Denitrification Performance of Modified Rice Husk Ash-Carbide Slag Absorbent

Materials ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 68
Author(s):  
Yali Wang ◽  
Xiaoning Han ◽  
Meina Chen ◽  
Suping Cui ◽  
Xiaoyu Ma ◽  
...  
Keyword(s):  
Functional Groups ◽  
Rice Husk ◽  
Rice Husk Ash ◽  
Research Direction ◽  
Cement Industry ◽  
Hydration Process ◽  
Air Pollution Control ◽  
Large Area ◽  
Carbide Slag ◽  
High Investment

In the cement industry, SO2 and NOx are generally removed separately. There are many problems, such as large area, high investment cost, secondary pollution and so on. Desulfurization and denitrification technology have become a frontier research direction in the field of air pollution control. In this paper, rice husk ash and carbide slag were compounded and modified to prepare modified rice husk ash-carbide slag composite absorbent, and its desulfurization and denitrification performance and mechanism were studied. The results showed that the NO conversion and SO2 conversion of the modified rice husk ash-carbide slag composite absorbent increased by 44% and 2%, respectively, at 700 °C. Fibrous calcium silicate and calcium silicoaluminate hydrates were formed during the hydration process, which made the specific surface area of the absorbent larger and provided more reactive sites. The hydration process increases the content of oxygen-containing functional groups, decreases the hydroxyl/ether C–O functional groups, and increases the content of carboxyl–COO functional groups are conducive to the denitrification reaction.

HPHT synthesis and enhanced TE performance of Te and Sn/Se elements binary-doped CoSb3

2019 ◽  
Vol 12 (01) ◽  
pp. 1850105 ◽  
Author(s):  
Hairui Sun ◽  
Pin Lv ◽  
Chao Wang ◽  
Yunxian Liu ◽  
Xiaopeng Jia ◽  
...  
Keyword(s):  
Experimental Data ◽  
Thermal Conductivity ◽  
High Pressure ◽  
High Temperature ◽  
Seebeck Coefficient ◽  
Grain Boundaries ◽  
Preparation Methods ◽  
Synthesis Time ◽  
Lattice Disorder ◽  
Positive Effect

A series of binary-doped CoSb3 with Te and Se/Sn bulk compounds Co4Sb[Formula: see text]TexSny/Sey ([Formula: see text] and 0.6, [Formula: see text] and 0.3), have been successfully prepared via a simple high pressure and high-temperature (HPHT) method. And, the influence of the doping elements on the microstructure of the samples synthesized under diverse pressures and the corresponding TE performance were studied in detail. Comparing with other preparation methods, the synthesis time of HPHT was acutely shortened. The obtained samples contain more grain boundaries, lattice disorder, dislocations and the possible “nanodot”, which have positive effect on reducing thermal conductivity. The experimental data indicate that the absolute values of Seebeck coefficient increases with pressure. What’s more, the thermal conductivities show a monotone decreasing trend as the synthesis pressure rises. The minimum value obtained is 1.93[Formula: see text]Wm[Formula: see text]K[Formula: see text] at normal temperature for Co4Sb[Formula: see text]Te[Formula: see text]Se[Formula: see text] prepared under 3[Formula: see text]GPa.

scholarly journals Investigation of Fatigue Behavior of ABS and PC-ABS Polymers at Different Temperatures

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 1818
Author(s):  
Andrea Mura ◽  
Alessando Ricci ◽  
Giancarlo Canavese
Keyword(s):  
High Temperature ◽  
Room Temperature ◽  
Working Condition ◽  
Fatigue Behavior ◽  
Polymeric Materials ◽  
Cyclic Loads ◽  
Structural Components ◽  
Working Temperature ◽  
Different Temperatures ◽  
Positive Effect

Plastics are widely used in structural components where cyclic loads may cause fatigue failure. In particular, in some applications such as in vehicles, the working temperature may change and therefore the strength of the polymeric materials. In this work, the fatigue behavior of two thermoplastic materials (ABS and PC-ABS) at different temperatures has been investigated. In particular, three temperatures have been considered representing the working condition at room temperature, at low temperature (winter conditions), and high temperature (summer conditions and/or components close to the engine). Results show that high temperature have big impact on fatigue performance, while low temperatures may also have a slight positive effect.

scholarly journals Sampling and Analysis of Alkali in High-Temperature, High-Pressure Gasification Streams

1985 ◽  
Author(s):  
Cynthia K. McCurry ◽  
Robert R. Romanosky
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Gas Turbines ◽  
Fixed Bed ◽  
Atomic Emission ◽  
Sampling System ◽  
Fuel Gas ◽  
Gas Streams ◽  
Coal Gasifier ◽  
High Temperature High Pressure

This paper describes the experiences leading to successful sampling of hot, contaminated, coal-derived gas streams for alkali constituents using advanced spectrometers. This activity was integrated with a multi-phase, combustion test program which addressed the use of minimally treated, coal-derived fuel gas in gas turbines. Alkali contaminants in coal-derived fuels are a source of concern, as they may induce corrosion of and deposition on turbine components. Real-time measurement of alkali concentrations in gasifier output fuel gas streams is important in evaluating these effects on turbine performance. An automated, dual-channel, flame atomic emission spectrometer was used to obtain on-line measurements of total sodium and potassium mass loadings (vapors and particles) in two process streams at the General Electric fixed-bed coal gasifier and turbine combustor simulator facility in Schenectady, New York. Alkali measurements were taken on (1) slipstreams of high temperature, high pressure, minimally clean, low-Btu fuel gas containing entrained particles from the gasifier and (2) a slipstream of the exhaust gas from the combustor/turbine simulator. Alkali detection limits for the analyzer were found to be on the order of one part per billion. Providing a representative sample to the alkali analyzer at the limited flows required by the instrument was a major challenge of this activity. Several approaches and sampling hardware configurations were utilized with varying degrees of success during this testing campaign. The resulting information formed the basis for a second generation sampling system which has recently been successfully utilized to measure alkali concentrations in slipstreams from the described fixed-bed coal gasifier and turbine combustor simulator.

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