IF 6.7 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2024-09-27 DOI: 10.1016/j.fuel.2024.133147

The present experimental study focuses on the determination of the oxidation progress and internal structures during the combustion of single iron particles using combined in-situ optical measurements and ex-situ material examination of rapidly quenched particles. Narrowly sieved iron particles with a mean diameter of 49 µm are ignited and burn in the hot exhaust of a premixed CH₄/O₂/N₂ flat flame with remaining 20 vol% O₂, provided by a laminar flow reactor with well-defined thermal and flow boundary conditions. During particle combustion, key parameters of oxidation progress are determined optically in a time-resolved manner, such as the time-resolved particle surface temperature and the reaction time relative to the instant of the particle peak temperature. Furthermore, individually burning particles are rapidly quenched at different combustion stages and then extracted from the exhaust gas using an isokinetic extraction probe. The bulk composition of the quenched particles with respect to

α

-Fe and its three oxides FeO, Fe₃O₄, and Fe₂O₃ is determined using Wide-angle X-ray Scattering and ⁵⁷Fe Mössbauer Spectroscopy. Combining the information obtained from in-situ and ex-situ measurements, it is shown that iron particles oxidize rapidly to FeO during the initial stage of combustion, followed by a much slower oxidation to Fe₃O₄ as the particles cool down. The peak particle temperatures are measured during the fast initial oxidation. Finally, particles sampled from representative positions of the oxidation process are analyzed by Energy-Dispersive X-ray Spectroscopy and Focused Ion Beam Scanning Electron Microscopy, revealing different particle morphology and internal structures. For the first time, the clear presence of an oxide shell and iron-core structure in quenched particles suggests that liquid iron and liquid iron oxide are layered during liquid phase combustion, if the particle remains within the miscible gap.

本实验研究的重点是利用原位光学测量和快速淬火颗粒的原位材料检测相结合的方法，确定单个铁颗粒燃烧过程中的氧化过程和内部结构。平均直径为 49 µm 的窄筛分铁颗粒在热边界条件明确的层流反应器提供的剩余 20 Vol% O2 的预混合 CH4/O2/N2 平焰的热排气中被点燃并燃烧。在颗粒燃烧过程中，以时间分辨的方式光学测定氧化过程的关键参数，如时间分辨的颗粒表面温度和相对于颗粒峰值温度瞬间的反应时间。此外，单独燃烧的颗粒在不同的燃烧阶段被迅速淬灭，然后使用等速萃取探头从废气中提取出来。利用广角 X 射线散射和 57Fe 莫斯鲍尔光谱测定了淬火颗粒中有关 α-铁及其三种氧化物 FeO、Fe3O4 和 Fe2O3 的主体成分。结合原位和非原位测量所获得的信息，结果表明铁颗粒在燃烧初期会迅速氧化成 FeO，随后随着颗粒冷却，会缓慢氧化成 Fe3O4。颗粒的峰值温度是在最初的快速氧化过程中测得的。最后，利用能量色散 X 射线光谱仪和聚焦离子束扫描电子显微镜分析了从氧化过程中具有代表性的位置取样的颗粒，揭示了不同的颗粒形态和内部结构。淬火颗粒中氧化物外壳和铁芯结构的明显存在首次表明，如果颗粒保持在混溶间隙内，液态铁和液态氧化铁在液相燃烧过程中是分层的。

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引用次数: 0

Rapid formation of carbon dioxide hydrate governed by the natural nano-clay for effective carbon dioxide capture 利用天然纳米粘土快速形成二氧化碳水合物，有效捕获二氧化碳

IF 6.7 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2024-09-27 DOI: 10.1016/j.fuel.2024.133291

Gas hydrate can separate and capture enormous carbon dioxide (CO₂) only using water cages. Capturing CO₂ in hydrate form is viewed as a green and effective technology to reduce the global CO₂ emission. However, the sluggish kinetics and high cost of kinetics promotors of CO₂ hydrate formation limited the application of hydrate-based CO₂ capture technology. Here, we used the nano-clay prepared by cheap natural clay to promote the formation kinetics of CO₂ hydrate. At the low concentration range, the formation period of CO₂ hydrate in the two-dimensional nano-clay dispersion was significantly shorter than that of the one-dimensional nano-clay dispersion. The induction time (5 min) obtained in vermiculite nanoflakes dispersion was shorter than most solid promotors of CO₂ hydrate formation kinetics in reported works. Besides, we found that the water molecules near the negatively charged two-dimensional nano-clay surface were more likely to form the cage-like structure than those around the one-dimensional nano-clay surface. The similar hydrogen-bonded structure of the cage-like water with CO₂ hydrate made them favorable for the CO₂ hydrate formation. These results shed light on the design of the effective kinetics promotors of CO₂ hydrate and contribute to develop the hydrate-based CO₂ capture technologies.

气体水合物只能利用水笼分离和捕获巨大的二氧化碳（CO2）。以水合物形式捕获二氧化碳被视为减少全球二氧化碳排放的一项绿色有效技术。然而，二氧化碳水合物形成的动力学缓慢且动力学促进剂成本高昂，限制了基于水合物的二氧化碳捕获技术的应用。在此，我们利用廉价天然粘土制备的纳米粘土来促进二氧化碳水合物的形成动力学。在低浓度范围内，二维纳米粘土分散体中 CO2 水合物的形成周期明显短于一维纳米粘土分散体。在蛭石纳米片分散液中获得的诱导时间（5 分钟）短于大多数已报道的二氧化碳水合物形成动力学固体促进剂。此外，我们还发现带负电荷的二维纳米粘土表面附近的水分子比一维纳米粘土表面附近的水分子更容易形成笼状结构。笼状水与二氧化碳水合物的氢键结构相似，因此有利于二氧化碳水合物的形成。这些结果为设计有效的二氧化碳水合物动力学促进剂提供了启示，有助于开发基于水合物的二氧化碳捕获技术。

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引用次数: 0

Calcium hypochlorite assisted energetically efficient sonic hydrolysis of waste activated sludge for cost effective biogas production 次氯酸钙辅助高能高效超声水解废弃活性污泥，实现经济高效的沼气生产

IF 6.7 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2024-09-27 DOI: 10.1016/j.fuel.2024.133217

The extracellular polymeric substances (EPS) in waste activated sludge (WAS) act as a protective barrier and limits the disintegration potential of the pretreatment process. In this study, an attempt was made to improve the disintegration potential of the pretreatment process by phase separating it into deflocculation and disintegration. In deflocculation, Calcium hypochlorite (Ca(ClO)₂) was used to remove EPS, and in disintegration, ultrasonication was used to solubilize the WAS. An effective deflocculation was achieved at an optimum Ca(ClO)₂ dosage of 0.02 g/g SS and a time of 15 min. The results of calcium hypochlorite-induced ultrasonication (CH-UP) revealed a substantial enhancement in suspended solids (SS) reduction, with a remarkable 18.42 % reduction compared to 11.57 % of ultrasonic pretreatment (UP). Additionally, the biodegradability of the sludge was evaluated using the biochemical methane potential test. The results showcased a notable increase in methane production, with CH-UP exhibiting a methane yield of 92.5 mL/g COD, compared to 68.2 mL/g COD for UP alone. Energy analysis reveals a higher and positive net energy production of 171.5 kWh/ ton for CH-UP compared to UP (−13.9 kWh/ton).

废弃活性污泥（WAS）中的胞外高分子物质（EPS）起着保护屏障的作用，限制了预处理过程的分解潜力。本研究尝试将预处理过程分为解絮凝和分解两个阶段，以提高预处理过程的分解潜力。在解絮凝过程中，使用次氯酸钙（Ca(ClO)2）去除 EPS；在解体过程中，使用超声波溶解 WAS。在 Ca(ClO)2 的最佳用量为 0.02 克/克 SS 和时间为 15 分钟时，可以实现有效的解絮凝。次氯酸钙诱导超声处理（CH-UP）的结果表明，悬浮固体（SS）的减少量大幅提高，与超声预处理（UP）的 11.57% 相比，显著减少了 18.42%。此外，还利用生化甲烷潜力测试评估了污泥的生物降解性。结果显示，甲烷产量显著增加，CH-UP 的甲烷产量为 92.5 mL/g（化学需氧量），而单独使用 UP 时的甲烷产量为 68.2 mL/g（化学需氧量）。能量分析表明，与 UP（-13.9 千瓦时/吨）相比，CH-UP 的净能量产量更高，达到 171.5 千瓦时/吨。

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引用次数: 0

Experimental analysis and optimization of the variable valve timing on attaining high efficiency with low NOx emission of a direct-injected hydrogen engine 可变气门正时对实现直喷式氢气发动机高效率和低氮氧化物排放的实验分析与优化

IF 6.7 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2024-09-27 DOI: 10.1016/j.fuel.2024.133199

The direct-injection hydrogen engine (DI-H₂ICE) has demonstrated zero carbon emissions with high brake thermal efficiencies (BTE). Due to the high stoichiometric air–fuel ratio of hydrogen, with a lean burn strategy the gas exchange process of a hydrogen engine is different to a gasoline engine, and the valve timing controlling strategy requires reinvestigation. In this research, the optimal variable valve timing (VVT) is investigated in a 2.0 L DI H₂ICE. The intake and exhaust valve timing controlling strategies are analyzed experimentally over the whole operating map. A multi-indicator decision-making method is applied to determine the entropy weight of BTE and NOx emissions. Results indicate that BTE greatly benefits from advanced intake valve timing, and exhaust valve timing affects BTE through pumping losses. Advanced intake and exhaust valve timings are employed in the hydrogen engine to enhance the BTE until the NOx emissions rise rapidly at high loads. The retarded exhaust valve timing helps reduce NOx emissions and avoid the risk of abnormal combustion at high loads. Therefore, earlier IVO and later EVC are applied simultaneously for DI-H₂ICE compared to the gasoline engine. A maximum power of 124.8 kW at an engine speed of 4500 rpm and a BTE of 42.57 % is achieved with optimized VVT. Furthermore, NOx emissions are controlled to under 20 ppm over nearly half of the engine operating map. The conclusions are valuable in the development of high-performance H₂ICEs, the numerical simulation studies, and hydrogen fuel applications.

直喷式氢气发动机（DI-H2ICE）已证明可实现零碳排放和高制动热效率（BTE）。由于氢气的高化学气燃比，在稀薄燃烧策略下，氢气发动机的气体交换过程与汽油发动机不同，因此需要重新研究气门正时控制策略。本研究对 2.0 L DI H2ICE 的最佳可变气门正时（VVT）进行了研究。通过实验分析了整个工作图上的进气和排气气门正时控制策略。应用多指标决策方法确定了 BTE 和 NOx 排放的熵权。结果表明，先进的进气门正时可大大提高 BTE，而排气门正时则会通过泵送损失影响 BTE。氢气发动机采用先进的进气和排气气门正时来提高 BTE，直到高负荷时氮氧化物排放量迅速上升。延缓排气门正时有助于减少氮氧化物排放，避免高负荷时异常燃烧的风险。因此，与汽油发动机相比，DI-H2ICE 同时采用了较早的 IVO 和较晚的 EVC。通过优化 VVT，在发动机转速为 4500 rpm 时可获得 124.8 kW 的最大功率和 42.57 % 的 BTE。此外，在近一半的发动机运行图中，氮氧化物排放量控制在 20 ppm 以下。这些结论对高性能 H2ICE 的开发、数值模拟研究和氢燃料应用都很有价值。

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引用次数: 0

Thermal index parameter investigation of coal–oxygen adsorption during low-temperature oxidation of coal 煤炭低温氧化过程中煤氧吸附的热指标参数研究

IF 6.7 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2024-09-27 DOI: 10.1016/j.fuel.2024.133277

Oxidative spontaneous combustion is an inherent property of coal. In which, coal oxygen adsorption heat is the decisive speed step of coal spontaneous combustion self-acceleration process, and coal oxygen adsorption heat is closely related to coal pore structure. By utilising an automatic physicochemical adsorption instrument, it was found that the form of pore existence in coal was dominated by mesopores, that the pore structure, oxygen uptake capacity and temperature varied non-linearly, and that pore size was positively correlated with pore volume; Using a self–built air adsorption calorimetric experimental system, it was found that when oxygen was involved in the adsorption reaction, the presence of oxygen would lead to a significant time lag in the adsorption equilibrium. Additionally, the transition temperature of coal adsorption mode has been determined to be 40 °C, shedding light on the mechanism behind the thermal self-accelerating reaction of coal oxygen adsorption; Using the correlation method, it was obtained that the index affecting the physical adsorption heat release is the percentage of mesopore volume in the coal, while the index affecting the chemical adsorption heat release is the pore size. The research findings are anticipated to offer theoretical backing for advancing flame-resistant materials.

氧化自燃是煤的固有特性。其中，煤氧吸附热是煤炭自燃自加速过程的决定性速度步骤，而煤氧吸附热与煤炭孔隙结构密切相关。利用自动理化吸附仪，发现煤中孔隙的存在形式以介孔为主，孔隙结构、吸氧量与温度呈非线性变化，孔隙大小与孔隙体积呈正相关；利用自建的空气吸附量热实验系统，发现当氧气参与吸附反应时，氧气的存在会导致吸附平衡出现明显的时间滞后。此外，还确定了煤炭吸附模式的转变温度为 40 ℃，揭示了煤炭吸附氧气的热自加速反应机理；利用相关方法得出，影响物理吸附放热的指标是煤炭中的中孔体积百分比，而影响化学吸附放热的指标是孔径。这些研究成果有望为阻燃材料的发展提供理论支持。

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引用次数: 0

Waste to energy: Enhancing biogas utilization in dual-fuel engines using machine learning based prognostic analysis 废物变能源：利用基于机器学习的预测分析提高双燃料发动机的沼气利用率

IF 6.7 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2024-09-27 DOI: 10.1016/j.fuel.2024.133093

Alternative fuels derived from organic matter like biomass can be a viable solution in the present scenario of increasing greenhouse gases. In the present study, waste food and animal refuse-derived biogas were tested as fuel in a diesel engine. To further enhance the waste-to-energy perspective waste cooking oil biodiesel − diesel blends were used as pilot fuel. A comprehensive set of operational settings including fuel injection timing, pressure, compression ratios, different flow rates of biogas, and engine loads were tested. Four machine learning approaches Linear Regression (LR), Decision Tree (DT), Extreme Gradient Boosting (XGBoost), and Gaussian Process Regression (GPR) were employed to develop prognostic models. The developed models for engine performance and emission were predicted with high accuracy with R² values as high as 0.9962 for brake-specific fuel consumption and 0.9948 for brake thermal efficiency. The prediction errors were low 0.06 for BTE during model training and 0.18 during the model testing phase while it was almost negligible in the case of BSFC. All models were compared using statistical metrics and violin plots. The DT-based forecasting models were observed to be the best among all the models both based on statistical measures as well as violin plots.

在温室气体日益增多的今天，从生物质等有机物中提取的替代燃料不失为一种可行的解决方案。在本研究中，废物食物和动物垃圾衍生的沼气被测试用作柴油发动机的燃料。为了进一步提高废物变能源的效果，还使用了废弃食用油生物柴油-柴油混合物作为试验燃料。测试了一整套操作设置，包括燃料喷射时间、压力、压缩比、不同的沼气流量和发动机负荷。采用了线性回归（LR）、决策树（DT）、极梯度提升（XGBoost）和高斯过程回归（GPR）四种机器学习方法来开发预测模型。所开发的发动机性能和排放预测模型具有很高的准确性，制动油耗的 R2 值高达 0.9962，制动热效率的 R2 值高达 0.9948。在模型训练阶段，BTE 的预测误差为 0.06，在模型测试阶段为 0.18，而 BSFC 的预测误差几乎可以忽略不计。所有模型都使用统计指标和小提琴图进行了比较。根据统计指标和小提琴图，基于 DT 的预测模型是所有模型中最好的。

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引用次数: 0

Kinetics of methane hydrate formation in a 1200 ml unstirred reactor for natural gas storage 用于天然气储存的 1200 毫升无搅拌反应器中甲烷水合物形成动力学

IF 6.7 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2024-09-27 DOI: 10.1016/j.fuel.2024.133295

Solidified natural gas (SNG) technology via clathrate hydrates, enhanced by promoters such as tetrahydrofuran (THF), promises large-scale natural gas storage due to its high volumetric capacity and mild storage conditions. Despite its potential for industrial scale-up, limited research exists on methane hydrate formation behaviors in large reactors (>1000 cm³), which is crucial for evaluating practical storage performance. In this study, methane hydrate formation kinetics were investigated in a scaled-up unstirred reactor (1200 cm³) at 288.15 K and 283.15 K, and 5.0 MPa. Methane uptake, system pressure, gas and liquid phase temperatures, and hydrate morphologies were analyzed to describe the dynamic hydrate formation process. Results reveal three effects of increased reactor size in contrast to smaller reactors: (i) heterogeneous distribution of THF-rich and methane-rich hydrates; (ii) hydrate bulk show a hollow inner structure with a cavity due to the wall-climbing behavior of hydrate growth; (iii) optimal THF concentration no longer always agrees with stoichiometric 5.56 mol%, which is case-dependent. These effects are attributed to higher diffusion resistances for methane molecules and more intensive heat accumulation. These findings provide some insight into the kinetics of methane hydrate formation in industrial reactors, which is critical for the commercialization of SNG technology.

在四氢呋喃（THF）等促进剂的作用下，通过凝块水合物形成的固态天然气（SNG）技术具有体积容量大、储存条件温和等优点，有望实现大规模天然气储存。尽管甲烷水合物具有工业放大的潜力，但有关其在大型反应器（1000 立方厘米）中形成行为的研究却十分有限，而这对于评估实际存储性能至关重要。本研究在 288.15 K 和 283.15 K 以及 5.0 MPa 的条件下，在按比例放大的无搅拌反应器（1200 cm3）中研究了甲烷水合物形成动力学。分析了甲烷吸收量、系统压力、气相和液相温度以及水合物形态，以描述动态水合物形成过程。结果显示，与较小的反应器相比，反应器尺寸增大会产生三种影响：(i) 富含 THF 和富含甲烷的水合物的异质分布；(ii) 由于水合物生长的爬壁行为，水合物块体显示出带有空腔的中空内部结构；(iii) 最佳 THF 浓度不再总是与化学计量 5.56 摩尔% 一致，这取决于具体情况。这些影响可归因于甲烷分子的扩散阻力增大和热量积累加剧。这些发现为工业反应器中甲烷水合物的形成动力学提供了一些启示，这对于合成天然气技术的商业化至关重要。

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引用次数: 0

Properties analysis of catalyst particles during stripper distributor fault in industrial fluid catalytic cracking unit 工业流体催化裂化装置中剥离器分配器故障时催化剂颗粒的性质分析

IF 6.7 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2024-09-27 DOI: 10.1016/j.fuel.2024.133279

Particle attrition is prevalent in fluid catalytic cracking (FCC) process, and severe particle attrition threatens the steady operation of FCC units. In this study, the processes of attrition and dealing in industrial FCC unit were investigated, and the relationship between particle physical properties and fault source was analyzed. The results showed that the most frequent particle sizes of the attrited equilibrium catalyst and the spent catalyst were 48.85 μm and 55.21 μm, respectively. The replacement of attrited catalyst by equilibrium catalyst with higher mechanical strength could alleviate the catalyst attrition problem, and the most frequent particle size of the catalyst remained at 75.81 μm after experiencing attrition. When the replacement rate reached 66.83 %, catalyst loss was reduced and the stability of FCC unit operation was significantly improved. This study would contribute to a deeper understanding of the particle abrasion and fragmentation behavior in different environments in industrial FCC units.

颗粒损耗在流体催化裂化（FCC）过程中非常普遍，严重的颗粒损耗威胁着 FCC 装置的稳定运行。本研究调查了工业催化裂化装置中的损耗和处理过程，并分析了颗粒物理性质与故障源之间的关系。结果表明，磨损的平衡催化剂和废催化剂最常见的粒径分别为 48.85 μm 和 55.21 μm。用机械强度更高的平衡催化剂替换磨损的催化剂可以缓解催化剂磨损问题，磨损后的催化剂最常见粒径仍为 75.81 μm。当更换率达到 66.83 % 时，催化剂损耗减少，催化裂化装置运行的稳定性显著提高。这项研究有助于深入了解工业催化裂化装置在不同环境下的颗粒磨损和破碎行为。

引用次数: 0

In situ decorated Mn-FeOx amorphous oxides on filter felt by a polyphenol-assisted method for low-temperature NH3-SCR 利用多酚辅助法在过滤毡上原位装饰 Mn-FeOx 非晶氧化物，用于低温 NH3-SCR

IF 6.7 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2024-09-27 DOI: 10.1016/j.fuel.2024.133289

The combination of dust filtration technology and selective catalytic reduction of nitrogen oxides can effectively reduce the energy consumption and footprint of the flue gas purification system. To fabricate the high efficiency and firmly bonded catalytic filter material, a novel polyphenol-assisted method was designed in this work for in situ decorating Mn-FeO_x amorphous oxides onto the smooth polyphenylene sulfide (PPS) filter felt. The polyphenolic compounds are not only worked as the dispersant, but also the binder for Mn-FeO_x catalysts to firmly anchor on PPS filter felts. The introduction of Fe³⁺ into catalyst precursors can increase the Mn⁴⁺ content, surface adsorbed oxygen, as well as surface acidity, which displays satisfactory denitration performance and SO₂ tolerance at low temperatures. The Mn₅Fe₁-TA/PDA@PPS sample shows nearly 100 % NO conversion efficiency at 180 °C with only 10.11 % catalysts loading in the sulfur dioxide free flue gas. Furthermore, the green and efficient synthesis route makes the catalytic filter felts preserve the same gas permeability and thermal stability with the pristine PPS filter felt, which suggests that the Mn₅Fe₁-TA/PDA@PPS has great prospects for simultaneously removing of NO_x and dust in practical applications.

粉尘过滤技术与选择性催化还原氮氧化物技术相结合，可有效降低烟气净化系统的能耗和占地面积。为了制备高效、粘结牢固的催化过滤材料，本研究设计了一种新型的多酚辅助方法，用于在光滑的聚苯硫醚（PPS）过滤毡上原位装饰 Mn-FeOx 非晶氧化物。多酚类化合物不仅可以作为分散剂，还可以作为粘合剂使 Mn-FeOx 催化剂牢固地固定在聚苯硫醚过滤毡上。在催化剂前驱体中引入 Fe3+ 可以增加 Mn4+ 的含量、表面吸附氧和表面酸度，从而在低温下显示出令人满意的脱硝性能和二氧化硫耐受性。Mn5Fe1-TA/PDA@PPS 样品在 180 °C 时的 NO 转化率接近 100%，而无二氧化硫烟气中的催化剂负载量仅为 10.11%。此外，绿色高效的合成路线使催化过滤毡保持了与原始 PPS 过滤毡相同的气体渗透性和热稳定性，这表明 Mn5Fe1-TA/PDA@PPS 在实际应用中具有同时去除氮氧化物和粉尘的巨大前景。

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引用次数: 0

Time-dependent variations in desorbed gas composition: methodological analysis of asphaltite vein investigation results 解吸气体成分随时间的变化：对沥青岩矿脉调查结果的方法分析

IF 6.7 1区工程技术 Q2 ENERGY & FUELS

Fuel

Pub Date : 2024-09-26 DOI: 10.1016/j.fuel.2024.133276

In this study, a phenomenon that can have significant technical and economic impacts in the mining and unconventional gas production of hydrocarbon resources is discussed, change of gas composition during desorption period. The change is analyzed, related findings are obtained and engineering tools are forged. In this scope, a member of the Southeastern Turkey asphaltite’s gas content and composition character was examined. 12+1 samples were collected at equal intervals from an inclined drillhole that cut through the asphaltite vein. The United States Bureau of Mines (USBM) direct method was employed to determine the gas content. Gas composition analysis was performed on gas samples, which were collected four times throughout the desorption period. Residual gas composition is determined as well. During desorption period, methane and hydrogen ratios exhibited decreasing trends, while others have increasing trends. In evaluating of the collected data, the desorption order between gas compounds are revealed. Logarithmic trend functions are generated to estimate the concentrations of gas compounds at specific time points. With these functions and gas content measurement data, weighted average concentrations for gas compounds are determined. These concentration functions and the weighted average results are used to create engineering tools showing unit energy content of desorbed gas through desorption period both instantaneous and cumulative. Similarly, change in lower explosive limit and auto-ignition temperature during desoption period is shown. The weighted average gas concentrations obtained are used to interpret geological insights as they are the actual gas composition of the samples. In the study, gas content characteristic properties of Üçkardeşler asphaltite vein is comprehensively presented. Accordingly, the mean gas content, excluding one sample with a value of 2.78 m³/t at a location near a fault intersection, was found to be 1.66 m³/t. The average volumetric concentrations of methane, ethane, propane, and acetylene in the desorbed gas were determined as 61.6%, 24.5%, 10.7%, and 2.3%, respectively. The remaining part primarily consisted of heavier hydrocarbons, with low amounts of carbon dioxide and hydrogen.

本研究讨论了在碳氢化合物资源的开采和非常规天然气生产中会产生重大技术和经济影响的一种现象，即解吸期间气体成分的变化。对这一变化进行了分析，得出了相关结论，并锻造了工程工具。在此范围内，对土耳其东南部沥青岩的气体含量和成分特征进行了研究。从一个穿过沥青岩矿脉的倾斜钻孔中以相等的间隔采集了 12+1 个样本。采用美国矿业局（USBM）的直接法测定气体含量。在整个解吸过程中，对收集了四次的气体样本进行了气体成分分析。同时还测定了残余气体成分。在解吸过程中，甲烷和氢的比例呈下降趋势，而其他气体则呈上升趋势。通过评估收集到的数据，可以发现气体化合物之间的解吸顺序。生成的对数趋势函数可估算出特定时间点的气体化合物浓度。利用这些函数和气体含量测量数据，可确定气体化合物的加权平均浓度。这些浓度函数和加权平均值结果可用于创建工程工具，显示解吸气体在解吸期间的单位能量含量，包括瞬时和累积值。同样，还可显示解吸期间爆炸下限和自燃温度的变化。获得的加权平均气体浓度可用于解释地质见解，因为它们是样品的实际气体成分。研究全面介绍了于奇卡尔德什勒沥青岩矿脉的气体含量特征特性。因此，除去一个位于断层交汇处附近、数值为 2.78 立方米/吨的样本外，平均含气量为 1.66 立方米/吨。经测定，解吸气体中甲烷、乙烷、丙烷和乙炔的平均体积浓度分别为 61.6%、24.5%、10.7% 和 2.3%。其余部分主要由较重的碳氢化合物组成，二氧化碳和氢的含量较低。

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引用次数: 0

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