超声波采油技术的原理及应用

文章介绍了超声波技术在油井增产，防蜡，防垢及除垢和对原油的降粘等方面的作用原理和作用效果，并说明了超声波采油的适用范围。     

强磁技术在石油工业中的应用

强磁场在科学研究和工业技术方面的应用是十分广泛的[1],强磁技术在石油工业中的普遍应用则还是近年来的事情. 1983年国外首先报道了让油流通过磁化器而获得降粘效果的消息.苏联在什卡波夫油田进行磁防蜡工业性试验中发现:在温度、流量给定的条件下,防蜡效果与磁场强度相关.美国 Hydrow Orld公司,采用永磁式磁化调节器,对输油管线进行处理试验,发现处理前需在冬天关闭的管线,处理后则能够四季畅通.据计算,处理前后原油凝固点下降5-10℃,苏联科技工作者,对同一油田中两口产油井的输油管道进行交流电磁场处理试验,发现油井产液量虽然保持稳定…     

声波在高含蜡油生产中防蜡作用的实验研究

含蜡原油在生产过程中,蜡组分随井筒温度的降低而逐渐析出,这种结蜡现象导致原油粘度急剧上升而影响油井的正常生产,因此采取防蜡措施在高含蜡原油生产中是必不可少的,利用声波进行防蜡的实验研究表明,声波作用可以破坏蜡晶网状结构,降低原油粘度和凝固点,从而达到防蜡的目的,声波防蜡以其独特的作用机理较其它防蜡方法具有更大的可靠性和更加广阔的应用前景。     

复配菌优化培养及其在原油中的应用研究

微生物除蜡、降黏技术因高效、经济、无毒、无污染的优点,被广泛研究和采纳。本论文主要研究了嗜蜡菌SL-7以及用BH-12进行复配制成微生物菌剂SB7-12的除蜡、降黏研究。实验结果表明:优化后的复配菌SB7-12对原油具有降黏与除蜡双重功效,对原油中石蜡的降解率达83.3%,降黏率可达到43.3%。显微镜结果表明,微生物菌剂的加入使原油中微观蜡晶结构呈现出小而分散的特点,表观黏度降低,从而有利于提高原油流动性。     

复配菌对原油微观结构变化的研究

含蜡原油因其蜡组分的存在使其在开采和运输的过程中易使蜡晶析出,蜡晶析出堵塞管道,减小输送半径,严重时会发生凝管停运等事故,造成严重的经济损失.本文利用已发现的一株嗜蜡菌与产表面活性剂菌株进行复配,利用得到的复配菌发酵液按一定比例接种于含蜡原油中,实验表明作用7天后的原油含蜡量降低;利用ImageJ软件对偏光显微镜图片进行后处理发现蜡晶结构变小且密集;最后利用FBRM技术分析得原油中大粒径所占比例减少,小粒径所占比例增多.复配菌作为一种新方法、新思路,可以有效地降低含蜡原油在开采和运输过程中产生的危害,减少经济损失.     

嗜蜡菌对含蜡原油除蜡降黏作用的影响

含蜡原油因其蜡组分的存在而导致原油在低温环境中黏度变大、流动性变差,而在管输的过程中,蜡晶的析出会降低管道的输送能力、甚至有堵塞管道的威胁。本文利用已发现的一株嗜蜡菌,利用其发酵液降解含蜡原油中的蜡组分,实验证明处理5天后的原油含蜡量降低、表观黏度下降,偏光显微镜观察油中蜡晶结构明显变小而分散。软件ImageJ对显微镜照片处理后测量得到:最大蜡晶粒径从609.1μm下降至72.1μm;平均费雷特径大小从79.1μm下降到50.3μm。     

声速和衰减系数与含蜡原油特性的关系

当含蜡原油的温度低于蜡的析出温度后,蜡晶将不断析出并相互交联成网状结构,若网状结构达到一定强度,原油将失去流动而凝结。在该过程中不仅含蜡原油的流动特性发生变化,原油的声速和衰减系数也发生变化。本研究结果表明：含蜡原油的超速及衰减系数均随温度降低而增大;含蜡原油在凝结温度前后表现出不同的声速与温度的对应关系;含蜡原油在凝结后的声速的温度的关系同原油的含蜡量有关;含蜡原油的衰减系数在接近凝结温度时急剧     

不同吸附材料在卷烟降焦减害中的应用

嘴棒吸附技术是卷烟降焦减害方法的一个重要研究及应用领域。本文重点对纳米材料、生物材料、分子筛等在卷烟降焦减害方面的研究及应用进展进行了综述。     

蜡晶对油水界面稳定性的耗散粒子动力学研究

随着油田的不断开发，石蜡结晶和油水乳化作用为含蜡原油的开采、运输和储存带来巨大挑战。本文采用耗散粒子动力学方法研究了石蜡相变结晶对油水界面稳定性的影响。首先，计算了石蜡分子的序参量，揭示了水分子和油分子均会促进石蜡分子形成有序的固态晶体结构。其次，发现随着蜡含量的增加，油–水界面的表面张力逐步提高，石蜡分子会提高油–水界面的稳定性。最后，得到油–水界、蜡–水界面，蜡–油界面表面张力随温度的变化关系(298～348 K)。结果表明，当温度低于308 K，油–水界面和蜡水界面都能维持其界面的稳定性。对于蜡–油界面，当温度高于308 K时，达到石蜡的析蜡温度，石蜡晶体逐步熔化，蜡–油之间的界面张力急剧减小，蜡油界面逐渐消失。     

基于原油最高温度点变化规律分析停输相变传热

采用分区法数学模型,利用等价比热容法处理析蜡潜热问题,追踪停输相变过程中管道内原油最高温度点位置的变化轨迹,确定管道内原油最终凝固位置,提出管道内原油全凝的判断依据。基于最高温度点位置的变化规律将传热过程分为四个阶段,重点讨论了各阶段中自然对流、潜热释放、传热方式转化对最高温度位置点变化的影响,结合Ra数变化分析了自然对流换热影响从强到弱的变化过程。深入探讨了停输相变过程中管道内固相率的变化及不同位置处原油温降曲线的特点。     

Rheology of PVC compounds. II. Effects of lubricants on fusion

The effect of calcium stearate and paraffinic wax on the progression of fusion of PVC compounds was investigated by a rheological method based on the capillary entrance pressure loss. It was found that calcium stearate can increase or delay fusion. The way in which fusion is affected changes with temperature and the presence or absence of paraffinic wax. Increased calcium stearate levels in compounds with wax enhance the fusion process. Increased calcium stearate levels in compounds without wax decrease fusion at relatively low temperatures but accelerate fusion at higher temperatures. Paraffinic wax delays the resin particle breakdown and the fusion process. At the same level of calcium stearate, simple compounds without wax fuse faster than compounds with wax.     

Experimental Study of Vibration Effects on Heat Transfer during Solidification of Paraffin in a Spherical Shell

Two effects that have been observed when metals and metal alloys are vibrated during solidification are a decrease in dendritic spacing, which directly affects density, and faster cooling rates and associated solidification times. Because these two effects happen simultaneously during solidification, it is challenging to determine the one effect independently from the other. Most previous studies were on metals and metal alloys. In these studies, the one effect, i.e., the decrease in dendritic spacing, might influence the other, i.e., the faster cooling rates, and vice versa. The direct link between vibration and heat transfer has not yet been studied independently. The purpose of this study was to experimentally investigate the effect of vibration only on heat transfer and thus solidification rate. Experiments were conducted on paraffin wax, because it had a clearly defined macroscopic crystal structure consisting of mostly large straight-chain hydrocarbons. The advantage of the large straight-chain hydrocarbons was that the dendritic spacing was not affected by the cooling rate. Experiments were done with paraffin wax inside hollow plastic spheres of 40 mm diameter with 1 mm wall thickness. The paraffin wax was initially in a liquid state at a uniform temperature of 60°C and then submerged into a thermal bath at a uniform constant temperature of 15°C, which was approximately 20°C below the mean solidification temperature of the wax. Experiments were conducted in approximately 300 samples, with and without vibration at frequencies varying from 10–300 Hz. The first set of experiments was conducted to determine the solidification times. In the second set of experiments, the mass of wax solidified was determined at discrete time steps, with and without vibration. The results showed that paraffin wax had vibration independent of solid density contrary to other materials, e.g., metals and metal alloys. Enhancement of heat transfer resulted in quicker solidification times and possible control over the heat transfer rate. The increase in heat transfer leading to faster solidifcation times was observed to first occur as frequency increased and then to decrease.     

蜡油和洗油的HPLC法测定

采用HPLC法测定蜡油和洗油的含量,通过以蜡油和洗油混合液质量比所得拟合曲线计算混合液中蜡油与洗油的质量比值,为生产中快速准确测定蜡油和洗油的混合溶剂比提供一种可行的方法。     

Platinum film patterning by laser lift-off using hydrocarbon film on insulating substrates

We achieved a successful laser lift-off of Pt films on fused quartz substrate, employing novel technique using a laser-patterned Apiezon wax, successive uniform Pt deposition, and final laser lift-off. The successful laser lift-off of the Pt film on fused quartz substrate using the wax suggests that the much lower decomposition temperature of the wax than that of the fused quartz is important as well as the difference in the thermal conductivity. PACS 78.66.Qn; 81.65.Cf; 42.62.Cf     

The study of compatibility of polyethylene and polypropylene by using irradiated polyethylene wax

The modification of the compatibility between polyethylene (PE) and polypropylene (PP) by using irradiated PE wax (PE wax) is the purpose of this study. In this part, polymer blends based on various ratios of PE and PP were blended with 2.5% PE wax in all the blend ratios to determine the optimum ratio of the blend to be compatabilized. The influence of PE wax as a compatibilizing agent for PE and PP blend was investigated through the measurements of thermal, mechanical and morphological properties. The PP/PE blends modified by this method showed higher mechanical properties than those of the unmodified blends. Also, stress and strain of the modified blend having ratio (60/40) PP/PE blend recorded the maximum mechanical behavior. Scanning electron microscopy (SEM) micrographs of modified blends showed an indication of strong interfacial adhesion and a smooth continuous surface in which giving a support to the effect of irradiated PE wax as a tool for improving the compatibility.     

Visualization of micromorphology of leaf epicuticular waxes of the rubber tree Ficus elastica by electron microscopy

Ultrastructural aspects of leaf epicuticular waxes were investigated in Ficus elastica by scanning and transmission electron microscopy. Glossy leaves of the rubber tree were collected and subjected to different regimes of specimen preparation for surface observations. F. elastica leaves were hypostomatic and stomata were surrounded with a cuticular thickening that formed a rim. The most prominent epicuticular wax structures of F. elastica leaves included granules and platelets. Without fixation and metal coating, epicuticular wax structures could be discerned on the leaf surface by low-vacuum (ca. 7Pa) scanning electron microscopy. In terms of delineation and retention of the structures, the combination of vapor fixation by glutaraldehyde and osmium tetroxide with subsequent gold coating provided the most satisfactory results, as evidenced by high resolution and sharp protrusions of epicuticular waxes. However, erosion of epicuticular wax edges was noted in the immersion fixed leaves, showing less elongated platelets, less distinct wax edges, and granule cracking. These results suggest that the vapor fixation procedure for demonstrating three-dimensional epicuticular wax structures would facilitate characterization of diverse types of waxes. Instances were noted where epicuticular waxes grew over neighboring epidermal ridges and occluded stomata. In cross sections, epicuticular waxes were observed above the cuticle proper and ranged approximately from 100nm to 500nm in thickness. The native leaf epicuticular waxes had many layers of different electron density that were oriented parallel to each other and parallel or perpendicular to the cuticle surface, implying strata of crystal growth. Such retention of native epicuticular wax structures could be achieved through the use of acrylic resin treated with less harsh dehydrants and mild heat polymerization, alleviating wax extraction during specimen preparations.     

Fracture behaviour of plant epicuticular wax crystals and its role in preventing insect attachment: a theoretical approach

It is known that attachment ability of insects depends among others on the texture of the substrate. On plant surfaces, covered with microscopic epicuticular wax crystals, insect attachment was found to be highly reduced for many insect species. In some plants, this effect may be explained by the contamination of insect adhesive organs (pads) by wax crystals. In the present study, mechanics of the wax crystals fracture during contact formation between insect adhesive pads and plant surface is examined, in order to explain the observed contamination of pads by wax. It is shown that mechanisms of the wax crystal fracture may be rather different, depending on the slenderness ratio of the crystals. Crystals with high values of the ratio may buckle elastically or in an elastic-plastic way. For five plant species under consideration, the critical value of the slenderness ratio for elastic buckling is 26.5, while for elastic-plastic buckling it is 18.7. If the values of the slenderness ratio are lower than the critical values, one has to consider bending of the crystals under the weight of insects. Although this study considered only crystals of a tubular shape, the general approach is valid also for crystals of other shapes.