The Comparative Study of Honghe Lignite Pyrolysis under the Atmosphere of Methanol and Nitrogen

2012 ◽  
Vol 512-515 ◽  
pp. 1784-1789 ◽  
Author(s):  
De Min He ◽  
Lin Zhang ◽  
Jun Guan ◽  
Qiu Min Zhang

The pyrolysis of Honghe lignite was investigated on low heating rate (about 20°C/min) conditions in a fixed bed reactor with 10g fed in. Nitrogen was used as carrier gas operating at the range from 50 to 200ml/min. And, the temperature was tested from 440 to 560°C, the pressure ranges from 0.1MPa to 1.2MPa. The yields of coal tar, char, water and gas were obtained in experiments. The maximum coal tar yield of 9.77% (dry coal) was achieved at 520°C, 50ml/min nitrogen flow rate, pressure 0.4MPa and 20 minutes holding time. Then methanol was injected in the system at the preheat temperature 240°C(a little higher than its critical temperature). The methanol flow rate, pressure and holding time were also taken into consideration. And the results were compared with those obtained in pyrolysis under nitrogen atmosphere. It showed that higher liquid yield with lower yields of char, gas and loss were obtained with the presence of methanol, but the differences of char yields were slight. The total sulfur removal for methanol presence is considerably higher than the absence of methanol in pyrolysis. Considering the mild conditions of the pyrolysis with presence of methanol, this method may be an appropriate way to make use of the lignite efficiently and environmentally.

2013 ◽  
Vol 291-294 ◽  
pp. 748-754
Author(s):  
De Min He ◽  
Jun Guan ◽  
Lin Zhang ◽  
Qiu Min Zhang

In this paper, the pyrolysis of Honehe Lignite in N2 and N2-Methanol atmospheres were investigated on a fixed-bed reactor. The methanol flow rate, pressure, temperature and holding time were studied. The maximum of coal tar yields 12.01% (with methanol injected in) and 9.61% (absence of methanol) were achieved on the conditions of 520°C, 0.5MPa, N2 flow rate 50ml/min, methanol flow rate 0.1ml/min and holding time 20min, and the relative growing rate was about 25.0%. The gas from coal pyrolysis was detected by GC, and the coal tar was reprocessed and then detected by GC-MS. While the solid char was detected by IR to study the change of oxygen functional group during coal pyrolysis in N2-Methanol atmosphere. Compared with that pyrolysis in N2 atmosphere, the components, characteristics and properties of coal tar, gas and solid char varied a lot. The results showed that the injection of methanol into the system changed the products yields and distribution. The results showed that the total yields of phenol, cresol and xylenol (short for PCX) in the Acidic were about 1.93% and 1.15% (daf) in two atmospheres respectively, the PCX yields with methanol injected was about 1.67 times higher than that absence of methanol.


2008 ◽  
Vol 26 (1) ◽  
pp. 23-34 ◽  
Author(s):  
Abdurrahman Saydut ◽  
Yalcin Tonbul ◽  
Candan Hamamci

Asphaltite, being petroleum originated solid fossil fuel, can be converted into a variety of secondary products such as light hydrocarbon gases, liquid product and high quality fuel char by means of pyrolysis. Liquefaction of Harbul (Silopi, Turkey) asphaltite,-0.60+0.25 mm particle size, and using flash pyrolysis was performed in a fixed bed reactor with a heating rate 40°C min−1 at a temperature ranging from 400 to 800°C under nitrogen atmosphere. The effect of temperature on conversion and liquid yield was examined. The flash pyrolysis temperature resulted in a large increase in the oil yield, tar, gases, large increase in the yield of hydrocarbon gases occurred as a result of temperature at 550°C which was attributed to an increase thermal cracking of pyrolysis vapours. The yield of asphaltite liquid at the condition of 550°C reached a maximum 19.66 wt %. The asphaltenes of the pyrolytic oils were precipitated by addition of n-pentane. Pentane solubles were fractioned by column chromatography into aliphatic, aromatic and polar fractions using n-hexane, toluene and methanol, respectively. The composition of these fractions from silica gel column chromatography of oil obtained by nitrogen pyrolysis was characterized by FTIR.


2018 ◽  
Vol 1 (3) ◽  
pp. 279-283 ◽  
Author(s):  
Fei Dai ◽  
Yalin Zhang ◽  
Endong Xia ◽  
Zhanquan Zhang ◽  
Zhihua Zhang ◽  
...  
Keyword(s):  
Coal Tar ◽  

2013 ◽  
Vol 873 ◽  
pp. 562-566 ◽  
Author(s):  
Juan Liu ◽  
Xia Li ◽  
Qing Jie Guo

Chlorella samples were pyrolysed in a fixed bed reactor with γ-Al2O3 or ZSM-5 molecular sieve catalyst at 600°C. Liquid oil samples was collected from pyrolysis experiments in a condenser and characterized for water content, kinematic viscosity and heating value. In the presence of catalysts , gas yield decreased and liquid yield increased when compared with non-catalytic pyrolysis at the same temperatures. Moreover, pyrolysis oil from catalytic with γ-Al2O3 runs carries lower water content and lower viscosity and higher heating value. Comparison of two catalytic products, the results were showed that γ-Al2O3 has a higher activity than that of ZSM-5 molecular sieve. The acidity distribution in these samples has been measured by t.p.d, of ammonia, the γ-Al2O3 shows a lower acidity. The γ-Al2O3 catalyst shows promise for production of high-quality bio-oil from algae via the catalytic pyrolysis.


Author(s):  
Yanbing Li ◽  
Rui Xiao ◽  
Baosheng Jin ◽  
Huiyan Zhang

As one of the fundamental issues of the new poly-generation system on the basis of gasification gas and coke oven gas, carbon dioxide reforming of methane experiments have been performed over coal chars derived from different parent coals in a lab-scale fixed-bed reactor (internal diameter 12 mm, length 700 mm). The char derived from TongChuan coal exhibited higher activity than other samples employed under the same conditions. After the reforming reaction, the char samples were covered with different amounts of carbon deposition which resulted in the surface areas decrease. As the flow rate of feed gas increased from 200 ml/min to 600 ml/min over the Xuzhou char sample at 1050 degrees Celsius, the conversion of methane decreased from 52.7% to 17.5% and the H2 /CO dropped from 0.75 to 0.55. While maintaining the flow rate of CO2 at 20ml/min at 1050 degrees Celsius, the mole ratio of reactants CH4/CO2 was varied from 1 to 1.75 which led to the H2/CO ratio increase from 0.75 to 1.2.


2013 ◽  
Vol 779-780 ◽  
pp. 1394-1397
Author(s):  
Jin Wei Jia ◽  
Xin Qian Shu ◽  
He Long Hui ◽  
Xing Min Fu ◽  
Shu Cheng Liu ◽  
...  

To investigate the effects of gangue on pyrolysis of municipal solid waste (MSW), pyrolysis of MSW with gangue has been conducted by TG and fixed-bed reactor, respectively. The effect of gangue on pyrolysis product yields and compositions of gaseous products was investigated and the obtained results were compared with similar experiments without gangue. It was shown that gangue can improve the pyrolytic reaction of MSW, reduce the char yield, increase the liquid yield. And influences of gangue on yields of H2, CO, CH4 and CO2 were more apparent, the yields of H2, CO and CO2 with gangue were improved 12.5%, 11.8% and 175%, respectively, conversely, the yield of CH4 was reduced 15.4% compared with no gangue.


2021 ◽  
Vol 12 (1) ◽  
pp. 46
Author(s):  
Jingliang Wang ◽  
Shanshan Wang ◽  
Jianwen Lu ◽  
Mingde Yang ◽  
Yulong Wu

The pyrolysis of pine sawdust was carried out in a fixed bed reactor heated from 30 °C to a maximum of 700 °C in atmospheric nitrogen and pressurized hydrogen (5 MPa). The yield, elemental composition, thermal stability, and composition of the two pyrolysis bio-oils were analyzed and compared. The result shows that the oxygen content of the bio-oil (17.16%) obtained under the hydrogen atmosphere was lower while the heating value (31.40 MJ/kg) was higher than those of bio-oil produced under nitrogen atmosphere. Compounds with a boiling point of less than 200 °C account for 63.21% in the bio-oil at pressurized hydrogen atmosphere, with a proportion 14.69% higher than that of bio-oil at nitrogen atmosphere. Furthermore, the hydrogenation promoted the formation of ethyl hexadecanoate (peak area percentage 19.1%) and ethyl octadecanoate (peak area percentage 15.42%) in the bio-oil. Overall, high pressure of hydrogen improved the bio-oil quality derived from the pyrolysis of pine biomass.


2014 ◽  
Vol 14 (1) ◽  
pp. 25
Author(s):  
Wiwut Tanthapanichakoon ◽  
Shinichi Koda ◽  
Burin Khemthong

Fixed-bed tubular reactors are used widely in chemical process industries, for example, selective hydrogenation of acetylene to ethylene in a naphtha cracking plant. A dynamic model is required when the effect of large fluctuations with time in influent stream (temperature, pressure, flow rate, and/or composition) on the reactor performance is to be investigated or automatically controlled. To predict approximate dynamic behavior of adiabatic selective acetylene hydrogenation reactors, we proposed a simple 1-dimensional model based on residence time distribution (RTD) effect to represent the cases of plug flow without/with axial dispersion. By modeling the nonideal flow regimes as a number of CSTRs (completely stirred tank reactors) in series to give not only equivalent RTD effect but also theoretically the same dynamic behavior in the case of isothermal first-order reactions, the obtained simple dynamic model consists of a set of nonlinear ODEs (ordinary differential equations), which can simultaneously be integrated using Excel VBA (Visual BASIC Applications) and 4th-order Runge-Kutta algorithm. The effects of reactor inlet temperature, axial dispersion, and flow rate deviation on the dynamic behavior of the system were investigated. In addition, comparison of the simulated effects of flow rate deviation was made between two industrial-size reactors.Keywords: Dynamic simulation, 1-D model, Adiabatic reactor, Acetylene hydrogenation, Fixed-bed reactor, Axial dispersion effect


Author(s):  
O¨zlem Onay ◽  
O¨. Mete Koc¸kar

In this study, the safflower seed (Carthamus tinctorius L.) was used as biomass sample for catalytic pyrolysis using commercial catalyst (Criterion-454) in the nitrogen atmosphere. Experimental studies were conducted in a well-swept resistively heated fixed bed reactor with a heating rate of 300°Cmin−1, a final pyrolysis temperature of 550°C and particle size of 0.6–0.85 mm. In order to establish the effect of catalyst ratio on the pyrolysis yields, experiments were conducted at a range of catalyst ratios between 1, 3, 5, 7, 10, 20% (w/w). The bio-oils were characterized by elemental analysis and some spectroscopic and chromatographic techniques.


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