Co-pyrolysis of polymethyl methacrylate with brown coal and effect on monomer production

Pyrolysis capillary gas chromatography has been applied to the study of the co-pyrolysis of polymethyl methacrylate (PMMA) with Slovakian brown coal with the aim of finding pyrolysis conditions yielding a maximum amount of methyl methacrylate (MMA). Effects of pyrolysis temperature and PMMA-coal weight ratios were investigated. Capillary gas chromatography coupled with mass spectrometric detector (cGC-MS) was used for MMA identification. The highest yield of MMA in the pyrolysate was obtained at 750 °C. The optimal PMMA-coal weight ratio for maximum MMA production lies in the interval 0.5 mg PMMA and 0.6-0.8 mg brown coal with an MMA yield of 64%. Coal addition to the sample affects species recombination in gaseous phase, augments MMA production at higher temperatures and eliminates degradation products of PMMA and coal pyrolysis. Different conversion diagrams are characteristic for thermal degradation of single PMMA and in the mixture with coal. Detailed mechanism of synergetic effects arisen during co-pyrolysis are not yet known. It was also found that lower pyrolysis temperatures are more suitable to study degradation mechanism and kinetics while higher temperatures are more applicable for identification purposes. MMA decomposes completely at 900 °C.     

Gas evolution kinetics of two coal samples during rapid pyrolysis

Quantitative gas evolution kinetics of coal primary pyrolysis at high heating rates is critical for developing predictive coal pyrolysis models. This study aims to investigate the gaseous species evolution kinetics of a low rank coal and a subbituminous coal during pyrolysis at a heating rate of 1000 °C s^− 1 and pressures up to 50 bar using a wire mesh reactor. The main gaseous species, including H₂, CO, CO₂, and light hydrocarbons CH₄, C₂H₂, C₂H₄, C₂H₆, C₃H₆, C₃H₈, were quantified using high sensitivity gas chromatography. It was found that the yields of gaseous species increased with increasing pyrolysis temperature up to 1100 °C. The low rank coal generated more CO and CO₂ than the subbituminous coal under similar pyrolysis conditions. Pyrolysis of the low rank coal at 50 bar produced more gas than at atmospheric pressure, especially CO₂, indicating that the tar precursor had undergone thermal cracking during pyrolysis at the elevated pressure.     

The effects of oxygen on the yields of polycyclic aromatic hydrocarbons formed during the pyrolysis and fuel-rich oxidation of catechol

To better understand the effects of oxygen on the formation and destruction of polycyclic aromatic hydrocarbons (PAH) during the burning of complex solid fuels, we have performed pyrolysis and fuel-rich oxidation experiments in an isothermal laminar-flow reactor, using the model fuel catechol (ortho-dihydroxybenzene), a phenol-type compound representative of structural entities in coal, wood, and biomass. The catechol pyrolysis experiments are conducted at a fixed residence time of 0.3 s, at nine temperatures spanning the range of 500-1000 °C, and under varying oxygen ratios ranging from 0 (pure pyrolysis) to 0.92 (near stoichiometric oxidation). The PAH products, ranging in size from two to nine fused aromatic rings, have been analyzed by gas chromatography with flame-ionization and mass spectrometric detection, and by high-pressure liquid chromatography with diode-array ultraviolet-visible absorbance detection. The quantified PAH products fall into six structural classes: benzenoid PAH, indene benzologues, fluoranthene benzologues, cyclopenta-fused PAH, ethynyl-substituted PAH, and methyl-substituted PAH. A comparison of product yields from pyrolysis and fuel-rich oxidation of catechol reveals that at temperatures <800 °C, where only two-ring PAH are produced in significant quantities, increases in oxygen concentration bring about increases in yields of the two-ring aromatics indene and naphthalene. At temperatures >800 °C, increases in oxygen concentration bring about dramatic decreases in the yields of all PAH products, due to oxidative destruction reactions. The smaller-ring-number PAH are produced in higher abundance under all conditions studied, and the oxygen-induced decreases in the yields of PAH are increasingly more pronounced as the PAH ring number is increased. These observations regarding PAH ring number, from the fuel-rich oxidation experiments with catechol, fully support our finding from catechol pyrolysis in the absence of oxygen: that PAH formation and growth occur by successive ring-buildup reactions involving the C₁-C₅ and single-ring aromatic products of catechol’s thermal decomposition. The yield/temperature data reported here represent one of the most extensive quantifications of the effects of oxygen on PAH produced during the pyrolysis of any fuel.     

Pyrolysis of scrap printed circuit board plastic particles in a fluidized bed

Pyrolysis behavior and corresponding pyrolysis products of printed circuit board plastic particles (PCBP particles) were investigated in a fluidized bed using TG-FTIR analysis system. PCBP particles were separated from crashed printed circuit boards using fluidized beds, 354 μm crashed plastic particles were pyrolyzed at the temperature ranging from 20 to 900 °C by a thermogravimetric analyzer. Two stages of decomposition were identified for PCBP particles under nitrogen conditions. The activation energy was 90.49 kJ/mol for the first-stage reaction and 137.80 kJ/mol for the second-stage reaction. Further, gas products, liquid products, and solid residues yielded in the fluidized bed were analyzed using an elemental analyzer and FTIR. It has been found that the liquid yields increased with an increase in pyrolysis temperature, and with an increase in superficial gas velocity. The main compositions of liquid products were aromatic compounds including substituted benzenes. Whereas, the solid products mainly contained char and fiberglass.     

Gasification rate analysis of coal char with a pressurized drop tube furnace

Two coal chars were gasified with carbon dioxide or steam using a Pressurized Drop Tube Furnace (PDTF) at high temperature and pressurized conditions to simulate the inside of an air-blown two-stage entrained flow coal gasifier. Chars were produced by rapid pyrolysis of pulverized coals using a DTF in a nitrogen gas flow at 1400°C. Gasification temperatures were from 1100 to 1500°C and pressures were from 0.2 to 2 MPa. As a result, the surface area of the gasified char increased rapidly with the progress of gasification up to about six times the size of initial surface area and peaked at about 40% of char gasification. These changes of surface area and reaction rate could be described with a random pore model and a gasification reaction rate equation was derived. Reaction order was 0.73 for gasification of the coal char with carbon dioxide and 0.86 for that with steam. Activation energy was 163 kJ/mol for gasification with carbon dioxide and 214 kJ/mol for that with steam. At high temperature as the reaction rate with carbon dioxide is about 0.03 s⁻¹, the reaction rate of the coal char was controlled by pore diffusion, while that of another coal char was controlled by surface reaction where reaction order was 0.49 and activation energy was 261 kJ/mol.     

The conversion of waste polystyrene into useful hydrocarbons by microwave-metal interaction pyrolysis

Waste polystyrene was pyrolyzed at temperatures as high as the melting point of aluminum into styrene and other substituted aromatic compounds. This temperature was attained by the interaction of microwaves with aluminum in the form of a tightly coiled wire, strips, and cylinder. The rate of reaction was found to depend on the size, shape and form. The reaction was faster for the coil, slower for strips and negligible for the cylindrical form. The yields of pyrolysis were also found to depend on size, shape and form of the metal. The products of the pyrolysis were found to contain 88 wt % liquid, 9-10 wt % gases and residual char. The liquid portion was collected using cold traps and measured, whereas the amount of gas was obtained by taking difference. The liquid portion was analyzed using GC/MS and found that it contains substituted benzene in addition to polycyclic aromatics and condensed ring aromatics. The gases were identified using acetylide formation and Baeyer's test. The products, formation, mechanism of the reaction, and nature of products are discussed.     

升温速率及热解温度对煤热解过程的影响

为了研究煤热解过程中升温速率及热解温度对热解产物分布及热解过程吸热量的影响,采用热重和热红联用技术对煤热解过程进行了分析.研究了不同升温速率和热解温度对煤热解过程的气态产物分布的影响,并对所产生的焦炭性质进行了分析.结果表明:煤的整个热解过程的吸热量随升温速率的增加而减小;煤热解产生的焦油组分含量包括芳香族、脂环族和脂肪族含量达到最大值所对应的热解温度随升温速率的增加产生滞后现象,但是煤热解产生的煤气成分随着升温速率增加而急剧释放;随着热解温度的升高,焦炭结构逐渐致密,裂纹及裂缝产生,芳香晶核增大,同时焦炭中的氧和氮含量由于含氮和含氧化合物的继续分解而降低.     

The effects of oxygen on the yields of the thermal decomposition products of catechol under pyrolysis and fuel-rich oxidation conditions

In order to investigate the effects of oxygen on the distribution of thermal decomposition products from complex solid fuels, pyrolysis and fuel-rich oxidation experiments have been performed in an isothermal laminar-flow reactor, using the model fuel catechol (ortho-dihydroxybenzene), a phenol-type compound representative of structural entities in coal, wood, and biomass. The gas-phase catechol pyrolysis experiments are conducted at a residence time of 0.3 s, over a temperature range of 500-1000 °C, and at oxygen ratios ranging from 0 (pure pyrolysis) to 0.92 (near stoichiometric oxidation). The pyrolysis products are analyzed by nondispersive infrared analysis and by gas chromatography with flame-ionization and mass spectrometric detection. In addition to an abundance of polycyclic aromatic hydrocarbons, catechol pyrolysis and fuel-rich oxidation produce a range of C₁-C₅ light hydrocarbons as well as single-ring aromatics. Quantification of the products reveals that the major products are CO, acetylene, 1,3-butadiene, phenol, benzene, vinylacetylene, ethylene, methane, cyclopentadiene, styrene, and phenylacetylene; minor products are ethane, propyne, propadiene, propylene and toluene. Under oxidative conditions, CO₂ is also produced. At temperatures <850 °C, increases in oxygen concentration bring about increases in catechol conversion and yields of C₁-C₅ and single-ring aromatic products—in accordance with increased rates of pyrolytic reactions, due to the enhanced free-radical pool. At temperatures >850 °C, catechol conversion is complete, and increases in oxygen bring about drastic decreases in the yields of virtually all hydrocarbon products, as oxidative destruction reactions dominate. Reactions responsible for the formation of the C₁-C₅ and single-ring aromatic products from catechol, under pyrolytic and oxidative conditions, are discussed.     

Optimum operating conditions for a two-stage gasification process fueled by polypropylene by means of continuous reactor over ruthenium catalyst

We studied fuel gas production by means of pyrolysis and steam reforming of waste plastics for applications in solid oxide fuel cells. More specifically, we evaluated the effects of pyrolytic gasification temperature, catalyst content, steam reforming temperature, and weight hourly space velocity for a Ru catalyst used in a 60 g h^− 1-scale continuous experimental apparatus, which consisted of a tank reactor for pyrolysis and a packed-bed catalytic reactor for steam reforming. Polypropylene (PP) pellets were used as a model waste plastic. Ru/γ-Al₂O₃ catalysts with two different Ru contents were investigated. To suppress residue formation, the optimum operating temperature of the pyrolyzer was 673 K. To ensure suppressed coke formation, sufficient carbon conversion to gaseous products, and minimized heat loss from the reactor, the optimum operating conditions for the reformer were determined to be 903 K and 0.11 g-sample g-catalyst^− 1 h^− 1 with a 5 wt.% Ru/γ-Al₂O₃ catalyst. The composition of the gas produced with the 5 wt.% catalyst was almost the same as that predicted by chemical equilibrium laws, and it was applicable for a direct hydrocarbon fuel cell.     

Py-MS Study of Sulfur Behavior during Pyrolysis of High-sulfur Coals under Different Atmospheres

In this study sulfur pyrolysis behavior of two Chinese high sulfur coals and their treated coal samples was investigated by Py-MS at a heating rate of 5 °C/min from room temperature to 1025 °C under hydrogen, helium and 2% O₂-He. It is found that the internal and external hydrogen do not show hydrogenation ability at temperature below 400 °C, due to no H₂S formation at this temperature region for all the coal samples. At temperature higher than 400 °C, not only the indigenous hydrogen but also indigenous oxygen can react with sulfur-containing radicals to form H₂S or SO₂. The evolution of H₂S and SO₂ displays the same profiles in pyrolysis of ZY pyrite-free coal under He, further revealing that after the breakage of C-S bond in the organic sulfur structure in coal to form sulfur-containing radicals, which can equally react with indigenous hydrogen and oxygen. The similar tendency between evolution of CO₂ and SO₂ and the same ending temperature also shows that not only C-S but also C-C bond can be broken in pyrolysis of ZY coals under 2% O₂-He atmosphere. However, unlike SO₂ evolution, CO₂ emission increases in the temperature ranging from 500 °C to 800 °C in LZ raw and deashed coals, implying the breakage of C-C bond at high temperature, which might be related to their low coal rank and high pyrite content.     

Hydrous pyrolysis of two kinds of low-rank coal for relatively long duration

Brown coal samples were treated with hot water in a stainless steel batch reactor at 623 K for 2-72 h. After this hot hydrous treatment, gas, oils, and residues were recovered. The resulting residues were chemically analyzed in detail to understand the reaction chemistry during hydrous pyrolysis. Oxygen functionalities were analyzed chemically with the titration method and carbon types in the residue were examined by solid-state ¹³C NMR measurement. Elemental analyses showed that the oxygen atoms in the residue decreased markedly up to 2 h while treatments longer than 48 h were also very effective in removing oxygen functionalities from brown coal. The detailed chemical analyses revealed that alcoholic hydroxyl and carboxyl groups were decomposed in the earlier stages of the treatment, and that ether bonds may be cleaved during the latter stages of the hot hydrous pyrolysis. Experiments using two kinds of brown coal gave very different results. A comparison of the chemical structure of these two coals revealed the origin of the difference; one of them has a greater amount of hydroaromatic moieties than the other, which act as a hydrogen source even during hydrous pyrolysis occurring at temperatures as low as 623 K.     

Nitrogen adsorption on carbonaceous materials: A comparison between static and dynamic methods

The purpose of this study was to investigate the influence of the method of adsorption of N₂ at − 196 °C on the isotherm obtained for, and hence derived textural parameters of, a wide series of carbonaceous materials (CM). Two pyrolyzed products, six activated carbons and two carbon blacks were used. The carbonized products were prepared by pyrolysis of cherry stones at 600 or 900 °C in nitrogen atmosphere (P-600, P-900). Three activated carbons were made by activation of P-600 at 275 °C in air and of P-900 at 850 °C in carbon dioxide or steam, whereas the remaining CM were commercial products. The adsorption isotherms for N₂ at − 196 °C were determined by static and dynamic methods in Quantachrome equipments. The CM were further characterized texturally by means of mercury porosimetry and helium and mercury density measurements. Because of the presence of helium in the adsorptive gas stream, the adsorption of nitrogen noticeably decreases for the CM containing micropores obstructed with tarry products (i.e. P-600 and the activated carbon prepared from it by air activation). For the rest of the activated carbons the adsorption increases, as they must possess narrow micropores having easier access to N₂ at − 196 °C. Helium causes a decrease in the degree of interaction between the nitrogen molecules in the gas stream and as a result the diffusion of nitrogen in pores of the adsorbent increases. For the carbon blacks, however, helium hardly affects the adsorption of nitrogen, except for at high relative pressures of this gas. Helium also influences the capillary condensation phenomenon occurring in mesopores. The variation percentages in the micro- and mesopore volumes are as high as 20 and 50, respectively. Such percentages as a rule are higher for the activated carbons.     

Effect of bed depth on characterisation of slow pyrolysis products

The trend towards separation of waste for material recovery could assist with the implementation of waste pyrolysis and gasification processes. Following the previous work on slow pyrolysis of segregated waste materials, this study investigated the effect of bed depth on the yields and properties of pyrolysis products in a fixed bed pyrolyser. The results showed that the bed depth had a strong influence on the properties of pyrolysis products but a small effect on the yield of products. Differences in the liquid yield between the two cases of bed depth (17-57 vol% of the reactor) were observed at temperatures above 500 °C while the difference in the char yield was negligible. The aqueous fraction was 5-15% higher for the bed depth of 57 vol% than for the bed depth of 17 vol%. Increase in the bed depth increased the H/C ratio by a factor of 2-6 in the char product and the CO/CO₂ ratio by a factor of 1.74 in the gas product but slightly decreased in the H/C ratio in the liquid product.     

Release of alkali and alkaline earth metallic species during rapid pyrolysis of a Victorian brown coal at elevated pressures

Possible reaction mechanisms responsible for the release of Na and Mg during pyrolysis at elevated pressures are described in this paper. In order to evaluate these mechanisms a Victorian brown coal, Loy Yang coal, was pyrolysed in a wire-mesh reactor at pressures up to 6.1 MPa at a heating rate of 1000 °C s⁻¹. Release of Na and Mg were quantified as functions of temperature and pressure. The results demonstrated that increasing pressure suppresses or promotes release of Na and Mg depending on the combination of pressure and temperature. The results obtained have been explained qualitatively by the proposed reaction mechanisms. At temperatures of 600 °C and lower, the release of Na and Mg from the pyrolysing coal/char particles, as light carboxylates, other organic salts and/or metals, was controlled by their diffusion through the pore system of the particles and, therefore, was suppressed by increasing pressure. At higher temperatures, the release of Na and Mg seems to be affected by the changes in intra-particle mass transfer mechanism due to increasing pressure as well as by chemical reactions responsible for the formation of volatile Na and Mg species.     

水分对神东煤热解产物分布的影响

为考察原料煤中水分对神东煤热解产物分布的影响,通过格金试验和固体热载体小试试验研究了神东煤中水分对热解特性的影响,得到神东煤在不同水分下热解产物的分布规律。格金试验表明,水分对神东煤热解产物中焦油和热解气收率有显著影响。随着水分降低,神东煤热解产物中焦油收率从9.98%降至4.92%,热解气收率从8.47%上升至11.07%,热解水收率从2.74%上升到5.94%。小试试验结果与格金试验趋势基本相同。随着原料煤中水分的降低,焦油收率下降,热解气收率上升;未经干燥的原煤在不同温度下热解的焦油收率比干燥后煤样平均高2.17%,热解气收率平均低1.58%。热解温度对H2和CO比例影响较大,对其他气体比例影响较小。研究结果表明,水分对神东煤的热解过程及其热解产物分布有显著影响,热解原料煤中水分的增加有利于抑制神东煤热解水和热解气的生成,提高焦油收率,因此有望通过控制原料煤中的水分来调节热解产物的分布。     

Study of the influence of pressure on enhanced gaseous hydrocarbon yield under high pressure-high temperature coal pyrolysis

The influence of pressure on the yield of gaseous hydrocarbon products derived from pyrolysis of Fushun and Xianfeng coals have been investigated in an anhydrous and confined system. Pyrolysis was performed in sealed gold tubes at 380 °C and under the pressures ranging from 50 to 250 MPa for 24 h. The results show that the effect of pressure on coal pyrolysis and product generation should not be ignored. For the Fushun and Xianfeng lignite, the yields of gaseous hydrocarbon generation increase by 9.1% and 12.7% when the pressure increases from 50 to 250 MPa, respectively. However, the yields of hydrogen gas decrease greatly with pressure. The hydrogen gas yields of Fushun and Xianfeng lignite decrease by 76.5% and 75.9%, respectively, when the pressure increases from 50 to 250 MPa. Yields of carbon dioxide gas of Fushun and Xianfeng coals were enhanced with increasing pressure by 7.4% and 8.9% respectively. Data of stable carbon isotope compositions reveal that the methane and ethane carbon isotope values are also affected by pressure, as they become heavier by approximately 1.2‰ (PDB) when the pressure is increased from 50 to 250 MPa. Simultaneously, the hydrogen isotope compositions of methane and ethane increase by 10.3‰ and 7.1‰, respectively. Our experimental results suggest that the increase in gaseous hydrocarbon yield is resulted from synthesis of carbon dioxide and hydrogen and pressure serves to facilitate the synthetic process.     

Influence of temperature and alumina catalyst on pyrolysis of corncob

Corncob has been investigated as an alternative feedstock to obtain fuels and chemicals via pyrolysis in fixed-bed reactor. The influence of pyrolysis temperature in the range 300-800 °C as well as the catalyst effects on the products was investigated in detail and the obtained results were compared. The results indicated that a maximum oil yield of 22.2% was obtained at a moderate temperature of 600 °C. The oil yield was reduced when the temperature was increased from 600 to 800 °C, whereas the gas yield increased.Pyrolysis oils were examined by using instrumental analysis, ¹H NMR spectroscopy and GC/MS. This analysis revealed that the pyrolysis oils were chemically very heterogeneous at all temperatures. It was determined that the most abundant compounds composing the bio-oil were phenolics.It was observed that the catalyst decreased the reaction temperature. Most of the components obtained using a catalyst at moderate temperatures was close to those obtained at high temperatures without using a catalyst. Moreover, the use of a catalyst and the high temperatures of the reactions also decreased the amount of oxygenated compounds produced.According to these results, corncob bio-oils can be used as fuel and constitute a valuable source of chemical raw materials.     

Degradation of a Victorian brown coal in sub-critical water

Conversion characteristics of a Victorian brown coal in sub-critical water were investigated. Pulverized brown coal was heated up to 623 K in flowing sub-critical water pressurized at 25 MPa. The total conversion of the coal into extract and non-condensable gas reached over 70 wt%-daf, which was appreciably higher than the maximum conversion (50 wt%-daf) with a sub-critical non-hydrogen donor solvent, 1-methylnaphthalene (MN). Laser-ionization-desorption mass spectrometry showed that the sub-critical water extract was richer in lower-molecular-mass compounds than the sub-critical MN one. Thus, degradation of the coal occurred more extensively in sub-critical water than in MN. Along with the conversion in sub-critical water, both the total contents of hydrogen and phenolic hydroxyls in the whole products remained nearly unchanged. This suggests comparable and simultaneous formation and decomposition of hydroxyls through hydrolysis of ethers/esters and dehydration condensation between hydroxyls/carboxyls, respectively. For detecting the hydroxyl formation, the coal was first heated at 623 K under an inert gas atmosphere until the formation of water and the other volatiles was completed. Then, the heat-treated coal (LY-H) was exposed to flowing sub-critical water. As expected, the net formation of phenolic hydroxyls from LY-H was detected as 0.8 mmol-OH/g-LY-H while that of hydrogen as 2.3 mmol-H/g-LY-H. Approximately a half of the hydrogen gain was explained as phenolic hydroxyls gain, suggesting the importance of hydrolysis of esters and ethers that formed carboxyls and alcoholic hydroxyls as well as phenolic hydroxyls.     

Influence of the concentration of ethanol and the interaction of compounds in the pyrolysis of acetylene and ethanol mixtures

The pyrolysis of acetylene, ethanol and acetylene-ethanol mixtures in the 975-1475 K temperature range has been studied. The purpose of this work is to analyze the variation of soot and gas products coming from the pyrolysis of acetylene when adding increasing amounts of ethanol. Gas and soot products coming from the pyrolysis of 30,000 ppm of acetylene and different concentrations of ethanol (0-20,000 ppm) have been identified and quantified, and the influence of the amount of ethanol added has been analyzed. Analyses are supported on model calculations run with Chemkin using a detailed gas phase chemical kinetic mechanism, including subsets for acetylene and ethanol reactions and PAH formation and consumption reactions. In addition, the sum of the soot obtained from the individual pyrolysis of acetylene and ethanol is compared with the results coming from the pyrolysis of the corresponding acetylene-ethanol mixtures in order to analyze the interaction when they react jointly. Experimental results highlight the importance of the relative concentration acetylene/ethanol in the mixtures. Moreover, the results show that adding very small concentrations of ethanol, i.e. up to 600 times lower than acetylene concentration, leads to a diminution on the production of soot from the pyrolysis of acetylene.     

基于过程强化与反应调控的煤定向热解制高品质油气产物基础研究及中试验证

对比了现有煤热解制油气技术的特点,从反应工程“三传一反”的角度系统分析和概括了煤热解过程中挥发分在颗粒内生成和释放、颗粒间扩散和反应器中停留等关键步骤中的热量、质量传递和挥发分二次反应对油气品质的影响,揭示了目前碎煤热解制油气技术普遍存在的目标产品产率低、品质差、含尘量高等技术难题的根源,并总结出煤定向热解调控的有效措施,即在挥发分生成和半焦缩聚段采用高温加热和快速传递的传热方式,在挥发分扩散过程中利用半焦床层重整焦油和过滤灰尘,在反应器中设置气体通道导流挥发分的定向溢出。针对研究团队前期开发的内构件移动床定向热解理念,介绍了导热板和集气腔等内构件的作用机制,即通过导热板和中心集气腔等内构件进行传热强化、热解气流动的有序引导,实现热量和挥发分的同向扩散和传递;通过移动床中颗粒的缓慢运动和床层的过滤作用除尘;概述了1~5 kg/次基础实验、反应器结构内传热和流动模拟,100 kg/次模试分析和1000 t/a中试验证的研究结果,充分证实了该技术在同步提高油气质量与品质、降低油中尘含量等方面的优势和对碎煤原料的适用性;基于上述研究形成了内构件定向热解技术及基于该技术的热/电-油-气联产技术。