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Comparison and application of different empirical correlations for estimating the hydrate safety mar
As the oil and gas industries continue to increase their activity in deep water, gas hydrate hazards will become more serious and challenging, both at present and in the future.Accurate predictions of the hydrate-free zone and the suitable addition of salts and/or alcohols in preparing drilling fluids are particularly important both in preventing hydrate problems and decreasing the cost of drilling operations.In this paper, we compared several empirical correlations commonly used to estimate the hydrate inhibition effect of aqueous organic and electrolyte solutions using experiments with ethylene glycol (EG) as a hydrate inhibitor.The results show that the Najibi et al.correlation (for single and mixed thermodynamic inhibitors) and the Ostergaard et al.empirical correlation (for single thermodynamic inhibitors) are suitable for estimating the hydrate safety margin of oil-based drilling fluids (OBDFs) in the presence of thermodynamic hydrate inhibitors.According to the two correlations, the OBDE composed of 1.6 L vaporizing oil, 2% emulsifying agent, 1% organobentonite, 0.5% SP-1, 1% LP-1, 10% water and 40% EG, can be safely used at a water depth of up to 1900 m.However, for more accurate predictions for drilling fluids, the effects of the solid phase, especially bentonite, on hydrate inhibition need to be considered and included in the application of these two empirical correlations....
2020-12-22 21:24:13浏览：71
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添加剂对烟气脱硫的强化作用
采用鼓泡式烟气脱硫反应装置,研究了己二酸、硫酸镁、无机盐A和无机盐B等4种添加剂的脱硫强化作用.实验结果表明:4种添加剂均能较明显地提高脱硫浆液的脱硫率,且添加无机盐A和无机盐B的脱硫效果更好;随着添加剂加入量的增加,脱硫率逐渐提高,综合考虑,本实验适宜的添加剂加入量为1.0 g/L.现场实际应用中加入质量比为1∶1的无机盐A和无机盐B作为复合添加剂,在使用2台循环泵、烟气流量约1 020 km3/h、初始SO2质量浓度由2 981 mg/Nm3增加至约3 843 mg/Nm3的条件下,脱硫率仍由81.79％提高到89.92％....
2020-12-09 22:57:44浏览：31
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添加剂对聚砜膜气体分离性能和结构的影响
以聚砜为膜材料,通过浸入沉淀相转化法制备聚砜平板膜.溶剂为N,N-二甲基乙酰胺,凝胶介质为水.以有机小分子无水乙醇、正戊醇、丙酮、磷酸三丁酯,有机大分子聚乙二醇(PEG-400,PEG-2000)和无机小分子无水氯化锂为添加剂来调节膜结构,通过渗透性、选择性和电镜图(SEM)来评价添加剂对膜性能、结构的影响,选择工业上适用于气体分离的添加剂.结果表明,聚乙二醇有较高的渗透性和选择性,其次为磷酸三丁酯,但由于聚乙二醇价格昂贵,所以选择磷酸三丁酯为较优添加剂....
2020-12-06 21:11:24浏览：52
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Comparison and Analysis of Fabric Deodorization Test Methods
The test methods of deodorization fabric are studied in daily life.In view of different deodorization fabrics and source gases,the detector tube method and gas chromatography-flame ionization detector (GC-FID) method were chosen to test the deodorizing rates of fabric and the influencing factors on deodorization test were discussed.Through the two methods,the residual concentration of odorous substance after adsorption can be measured,and the deodorizing rates of deodorization fabric can be got by calculation.The results show that the two test methods are both appropriate for deodorization test of fabric....
2020-12-06 21:11:24浏览：45
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A New Grade Carbon Black Produced by Thermal Plasma Process
This paper presents a new route about producing carbon black, by which the naturalgas cracking is carried out in the absence of oxygen thanks to an electric energy supply externallygiven by a plasma jet. The carbon black produced by this process has a narrow size distributionand a small average diameter of 38 nm as well as a highly branched aggregate. The higher DBPvalue of 1.40 ml/g shows it should be a high structure carbon black. The FTIR spectra shows thatthere are lots of aromatic c-c bonds and a large amount of nitrogen-containing functional groupson the carbon blacks surface, such as -NH, -CN as well as -CH, -OH, -COOH groups....
2020-11-11 22:33:38浏览：48
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Comparisons between different models for thermal simulation of GTAW process
Two mathematical models are built to study the effects of the fluid flow on thermal distributions of the gas tungsten arc welding(GTAW) process. One model is based on the heat conductivity equation, which doesn' t take the effects of the fluid flow into account, and the other couples the laminar heat transfer and fluid flow in the weld pool, which is called laminar fluid flow model in short. The simulated results of the two models show that the pattern and velocity of the fluid flow play a critical role in determining the thermal distribution and the weld pool shape. For the laminar fluid flow model, its highest temperature is 400 K lower than that calculated with the other model and the depth of its weld pool is shallower too, which is mainly caused by the main vortex of the flow in the weld pool....
2020-11-11 22:33:38浏览：39
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Geochemical characteristics and formation process of natural gas in Kela 2 gas field
On the basis of a large amount of natural gas components and the carbon isotope as well as some other analysis data in Kela 2 gas field, the geochemical characteristics, source, origin, and formation process of natural gas have been discussed. The components of gas in the field tend to be "dry", and the drying coefficient is close to 1.0. The carbon isotope tends to be heavier, for instance, the average of 13C1 is 27.36‰ and that of 13C2 is 18.5‰. Comprehensive analysis shows that humic natural gas in the Kuqa petroleum system comes mainly from Triassic and Jurassic source rocks, and the contribution of Jurassic source rocks to the pool maybe is more than that of Triassic rocks. The main cause that the gas tends to be dry and bears heavier isotope composition lies in the fact that Kela 2 natural gas is the accumulation of late production of humic source rocks, and it is affected by the abnormal high pressure as well. Considering the hydrocarbon generating and structural history, we can regard the gas pool formation processes as twice filling and twice adjusting (destroying), that is, the filling and destroying process in the early Himalayan movement and the filling and adjusting in the late Himalayan movement....
2020-11-11 22:33:38浏览：38
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Purification technology of flue gas from remelting process of aluminum alloy tailings
Through a practical example of treatment of the flue gas from the remelting process of aluminum alloy tailings, the design and calculation method of exhaust hood, as well as the principles and the equipments of dust removal, smoke abatement and harmful gas elimination were studied. Combination of centrifugal and wet dust removal can purify the dust high efficiently. The carbon black and harmful gases in the flue gas can be removed by adding a small quantity of activator to the absorption solution. The application results are that the dedusting efficiency is 97.43%, Cl2 control efficiency is 88.03%, the exhaust fume blackness is lower than Ringelman number I, and the purification device resistance is 1126Pa....
2020-11-11 22:33:38浏览：39
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Evaluation of Process Capability in Gas Carburizing Process to Achieve Quality through Limit Design
Steel is the most important metallic material used in industry. This is because of the versatility of its engineering properties under different conditions. In one condition it can be very mild, soft and suitable for any forming operation. In another condition the same steel can be very hard and strong. This versatility is made possible by the different heat treatments that the steel can be subject to. One such treatment is Gas carburizing. This is the most widely used process for surface hardening of low carbon steels. In this method the surface composition of the steel changes by diffusion of carbon and or nitrogen and result in hard outer surface with good wear resistance properties. A striking feature of Gas Carburizing process is that in this process the original toughness and ductility remains unaffected even after heat treatment. 3% nickel chromium case hardened low carbon steels are widely used for critical automotive and machine applications such as rack and pinion, gears, camshaft, valve rocker shafts and axles which requires high fatigue resistance. Fatigue behaviour of case carburized parts depends to a great extent on the correct combination of Hardness Penetration Depth (HPD) and the magnitude of hardness at the surface and beneath the surface with low size and shape distortion. In order to reduce the manufacturing costs in terms of material consumption and elimination of the number of processing steps, the effect of Gas carburizing parameters on the fatigue behaviour should already be considered in the parameter design stage. Therefore it is of importance to optimize the gas carburizing process variables to attain quality products with respect to hardness and case depth. In the present paper, the evaluation of process capability was carried out through a Limit Design Concept called orthogonal array design of experiment. To optimize the process variables the influence of several parameters (Holding time,Carbon potential, Furnace temperature and Quench time) of the gas carburizing process on the micro hardness, total case depth, effective case depth and level of distortion of AISI 8620 steel were discussed....
2020-11-11 22:33:38浏览：47
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Nox reduction in the sintering process
A new process, NOx reduction with recycling flue gas and modifying coke breeze, was proposed. The effects of modified coke breeze and recycled flue gas on NOx reduction were investigated by sinter pot tests. The results show that the NOx reduction rate is over 10wt% in the sintering of modified coke breeze, the effects of the additives on NOx reduction are: CeO2CaOK2CO3.The NOx reduction rate increases with the amount of recycled flue gas, and is 22.35wt% in the sintering with recycling 30vo1% of the flue gas. When 30vo1% of the flue gas is recycled into the sintering of CeO2, CaO, and K2CO3 modified coke breeze, the NOx reduc-tion rates are 36.10wt%, 32.56wt%, and 32.17wt%, respectively....
2020-11-10 09:33:08浏览：30
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Microstructure evolution of A1-Si semi-solid slurry by gas bubble stirring method
A novel technique of introducing gas bubble stirring during solidification was studied to prepare Al-Si semi-solid slurry.The microstructure evolution of the slurry during slow cooling process after stirring was investigated.The effects of the solidification rate on the microstructure of the semi-solid slurry were investigated under three different solidification conditions.The results show that fine non-dendritic slurry can be obtained using the gas bubble stirring method.Ripening and coarsening of primary Al grains are observed during the slow cooling process,and at last coarsened eutectic Si appears.Primary Al grains with different sizes and eutectic Si are obtained,corresponding to three different solidification rates....
2020-11-03 10:30:25浏览：35
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Flow Characteristics in an External-Loop Airlift Slurry Reactor
The local flow characteristics in an external-loop airlift slurry reactor were investigated.The axial profiles of the local gas holdup,the Sauter mean diameter and the rise velocity were obtained.It was found that the bubble size and rise velocity were influenced by the solid holdup,and the bubble coalescence was enhanced by the increase of the solid holdup.A new correlation was used to predict the slip velocity between the gas phase and the slurry phase by taking into account the local gas holdup,the bubble size,and the physical properties of the experimental system.By using this correlation,the local drag coefficient can be calculated in the bubble swarm....
2020-11-03 10:30:25浏览：30
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Porous Cube-like In2O3 Nanoparticles and Their Sensing Characteristics toward Ethanol
Porous cube-like crystalline In2O3 nanoparticles with an average diagonal length of 34.8 nm were fabricated by a laser ablation-reflux process to form In(OH)3, followed by a calcination treatment to yield porous In2O3. HRTEM (high-resolution transmission electronic microscopy), XRD (X-ray diffraction), BET (Brunauer-Emmett-Teller), and XPS (X-ray photoelectron spectroscopy) analysis were used to characterize their crystalline structures, grain sizes, surface areas, and surface compositions. The as-prepared porous indium oxides were tested for their sensing properties toward ethanol. Non-porous In2O3 nanopowder (about 40 nm) was also examined in order to compare the results with the as-prepared porous In2O3 nanomaterials. The porous In2O3 exhibited much better performance than that of non-porosus In2O3, and showed enhanced sensitivity with a lower detection limit than other reported In2O3-based materials when exposed to ethanol. Good gas sensitivity and linear behavior as a function of ethanol concentration were observed in the porous In2O3 nanoparticles....
2020-10-22 17:35:41浏览：38
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Preparation and Ethanol Sensing Properties of ZnO Nanofibers
ZnO nanofibers with an average diameter of about 90 nm were prepared by an electrospinning method combined with a calcination process.The as-electrospun nanofibers before and after calcination were characterized by means of differential thermal analysis(DTA),thermal gravimetric analysis(TGA),X-ray diffraction(XRD) and scanning electron microscopy(SEM).The fibers after calcination at 600 ℃ belong to the hexagonal wurtzite structure.The sensor based on ZnO nanofibers exhibited excellent ethanol sensing properties at 206 ℃ such as good linear dependence in the low concentration(1-100 μL/L),high response,and good selectivity.Fast response(less than 2 s)and recovery(about 16 s) were also observed in our investigations....
2020-10-22 17:35:41浏览：38
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焦炉煤气非催化部分氧化制合成气实验研究与数值模拟
在带有单孔喷嘴石英管反应器实验的基础上,对焦炉煤气非催化部分氧化工艺制合成气进行了研究,分析了O_2/GAS比对合成气各组分含量的影响,反应器中反应过程和温度分布及出口产品组成.实验结果表明CH4转化率随O_2/GAS比增大而增大,O_2/GAS比调节到0.22～0.26时,CH_4转化率达到95%～97%,此时合成气CH_4含量低于1%.利用CFD软件平台对转化反应器进行了数值模拟.模拟结果显示,流量一定时出口气体组分H_2与CH4分别随着进气氧气与焦炉煤气体积流量比值的增加而减少.CO和CO_2分别随着比值的增加而增加.出口气体有效组分摩尔分数随进气流量的变化不是非常明显.在壁面温度为1 100 K时转化效果最好....
2020-10-02 20:35:09浏览：30
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天然气催化部分氧化制合成气工艺模拟及中试放大
利用Aspen plus软件,对天然气催化部分氧化制合成气的中试工程问题进行了研究,通过模拟计算及中试试验,考察了原料气的进料方式、预热温度以及放热氧化反应与吸热重整反应的能量耦合等对反应过程的影响.热力学计算结果表明,在2 MPa的压力下,反应温度需高于1273 K,合成气收率才能大于80％,而在近似绝热的反应条件下原料气预热温度则需控制在773 ～ 923 K.开发出适于天然气催化部分氧化制合成气的热量耦合型固定床反应装置,进料方式采用双流道外混合型喷嘴,模拟计算及中试试验表明该技术方案可行....
2020-10-02 20:35:09浏览：68
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固相萃取-气相色谱法测定合成气制烯烃产物中的含氧化合物
采用 C18固相萃取技术对合成气制烯烃（SGTO）的产物进行预处理，将产物分离为含氧化合物与烃类，采用气相色谱-质谱法（GC-MS）考察分离效果并鉴定产物中的含氧化合物，使用氢焰离子化检测（ FID）定量实际样品中的含氧化合物，使用其正构2-酮、正构醇的响应因子作为同碳数酮、醇的 FID 响应因子。优化 C18小柱洗脱条件，使用标准样品比较预处理前后的方法回收率。醇类标准品回收率为88％~98％，酮类标准品回收率为64％~87％。在197~4785 mg / L 范围内，标准品具有较好的线性关系，相关系数均大于0.99。定性并定量测定了 SGTO产物中的67种含氧化合物，发现正构醇、正构2-酮为 SGTO 产物中的主要含氧化合物，同时存在少量其他异构体。该方法操作简单、快速、样品需求量小，并能够在10 min 内完成样品的预处理。分析结果为 SGTO 工艺催化剂、动力学深入研究提供了必要的基础数据。...
2020-10-02 20:35:09浏览：55
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联合两段氧化制合成气/F-T合成的GTL工艺和催化剂
A novel process for catalytic oxidation of methane to synthesis gas (syngas), which consists of twoconsecutive fixed-bed reactors with air introduced into the reactors, integrated Fischer-Tropsch synthesis, was inves-tigated. At the same time, a catalytic combustion technology has been investigated for utilizing the F-T offgas togenerate heat or power energy. The results show that the two-stage fixed reactor process keep away from explosionof CH4/O2. The integrated process is fitted to produce diesel oil and lubricating oil in remote gas field....
2020-10-02 20:35:09浏览：37
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合成气发酵梭菌C.autoethanogenum的生长特性与CO发酵性能
为探讨合成气发酵乙醇的新工艺,对梭菌C.autoethanogenum的生长特性及CO发酵性能进行了研究.考察了不同碳源对C.autoethanogenum生长的影响,发现木糖是其生长的最佳底物.对生长培养基进行了改良,使C.autoethanogenum的菌体质量浓度提高2倍以上,代谢产物以乙酸为主,只产生少量乙醇.利用1L气体采样袋研究了C.autoethanogenum的CO发酵性能,在1.0g/L酵母膏的发酵培养基中经过两次CO发酵后,乙醇质量浓度达3.464 g/L,CO乙醇转化率达51.7％.研究表明:N2环境、180℃、4MPa下,20 min高温液态水处理蔗渣得到的水解液可用于C.autoethanogenum的培养,培养液再进行CO发酵,经过一次发酵后得到的乙醇质量浓度为3.13g/L,CO乙醇转化率为46.9％,与之前两次发酵的结果接近,但是发酵时间大大缩短....
2020-10-02 20:35:09浏览：64
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合成气制低碳烯烃铁基催化剂制备研究现状
论述了合成气制低碳烯烃铁基催化剂的研究现状，并对未来的发展前景进行展望，以期为铁基催化剂的进一步研究提供参考。...
2020-10-02 20:35:09浏览：40
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合成气经草酸酯法制取乙二醇的技术进展
分析了当前国内乙二醇的供需状况和发展煤制乙二醇的优势;论述了草酸酯法制取乙二醇的工艺原理、工艺流程和技术进展;指出加强草酸酯加氢催化剂的研究并建立一定规模的工业化示范装置是合成气经草酸酯法制乙二醇工艺技术进入大规模工业化生产的当务之急。...
2020-10-02 20:35:09浏览：82
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煤制乙二醇装置羰化合成气相组分优化探讨
濮阳永金煤制乙二醇装置羰基化合成系统在高负荷运行情况下，气相中惰性组分CO2持续上涨，严重影响了主要反应物CO与MN的比例。经过对尾气系统操作压力的调整，以及对调整过程中数据的分析，采取了适当降低尾气操作压力的措施，有效地抑制了CO2的上涨，维持合成气相组分稳定。...
2020-10-02 20:35:09浏览：35
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天然气蒸汽转化改造制乙二醇合成气方案的研究
针对国内某项目利用原先已有天然气蒸汽转化装置为新建200 kt/a煤基合成气制乙二醇工业示范装置提供备用合成气源的改造要求,提出了纯氧配CO2和水蒸气、纯氧配CO2,纯氧等3种可行方案,通过对一、二段转化炉、烧嘴及炉体材料等指标进行对比,并对不同方案改造后各装置运行情况及实际生产能力、不同方案投资及技术经济指标进行了测算,最终选择纯氧配CO2和水蒸气方案.该方案可以实现稳定供应原料气的目的,装置可在不同工况下保持较高的乙二醇生产平均负荷(工况1,2为满负荷生产),合成氨产量可达1.1 kt/d,方案总投资3 083.0万元,有项目和增量所得税后净利润分别为3.8,2.3亿元/a,投资回收期1.1a.该方案具有投资整体省、经济效益优的特点.改造后装置运行平稳、操作简单,达到增产乙二醇及合成氨的目的....
2020-10-02 20:35:09浏览：35
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生物质炭水蒸气气化制取合成气
在常压固定床反应器中,以生物质炭为原料进行水蒸气气化制取合成气研究.实验在温度800 ～ 1000℃和水蒸气流量0.083 ～ 0.285g/(min·g char)条件下进行,反应时间为15min,研究反应温度和水蒸气流量对生物质碳转化率、合成气产率及合成气组分的影响.研究结果表明:生物质炭水蒸气气化具有很高的反应活性,气体产率在0.40 ～ 2.97L/g之间；温度和水蒸气流量对碳转化率和合成气热值及组分影响显著；在反应温度1000℃、水蒸气流量0.285g/(min·g char)时,碳转化率达到最高值78.7％；气体产物主要由H2、CO、CO2和CH4组成,合成气热值在8.9 ～ 9.6MJ/Nm3之间,合成气中(H2 +CO)在68％ ～ 80％之间,(H2/CO)在3.1 ～6.4之间....
2020-10-02 20:35:09浏览：69
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合成气甲烷化工艺技术研究进展
合成气完全甲烷化技术是煤制天然气特有的技术，按照反应器类型，合成气甲烷化工艺可以分为绝热固定床、等温固定床、流化床和浆态床等工艺，其中绝热固定床甲烷化工艺成熟并广泛应用于煤制天然气项目。本文介绍了多种绝热固定床甲烷化工艺，并比较了5种高温绝热固定床甲烷化工艺的流程、技术特点和应用情况。随着研究工作的不断深入，国内绝热固定床甲烷化技术达到了国际技术同类水平，具备了工业化应用条件，但还需在节能降耗、提高催化剂寿命方面加大研究力度。还概述了等温固定床、流化床和浆态床甲烷化工艺，分析了等温固定床、流化床和浆态床甲烷化工艺存在的问题，并指出了后续研究重点，等温固定床工艺应在反应温度控制和反应器开发方面深入研究，流化床甲烷化工艺研究重点放在开发高强度催化剂和工程化放大方面，浆态床甲烷化工艺需要重点研究解决CO转化率较低和催化剂损耗严重的问题。...
2020-10-02 20:35:09浏览：25
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