本文選題：高含硫氣藏 + 硫沉積��； 參考：《西南石油大學(xué)》2017年碩士論文

【摘要】：高含硫氣藏在世界分布廣泛,在氣井開采過程中,隨著溫度和壓力的變化,會發(fā)生相變,氣體中析出單質(zhì)硫,當(dāng)單質(zhì)硫不能被氣體攜帶走時,就會產(chǎn)生硫沉積現(xiàn)象,堵塞孔喉,傷害地層,嚴(yán)重影響高含硫氣井產(chǎn)能。目前關(guān)于硫沉積機(jī)理研究主要采用宏觀實驗和理論手段,對元素硫顆粒的微觀運(yùn)移沉積機(jī)理認(rèn)識不清,有必要采用微觀尺度研究方法。因此,從微觀角度利用氣固耦合方法模擬研究元素硫顆粒微觀運(yùn)移沉積機(jī)理,重點(diǎn)考慮元素硫顆粒運(yùn)移過程中受到的重力、曳力、浮力以及硫顆粒碰撞聚團(tuán)過程中受到的粘結(jié)力,分析硫顆粒的析出方式,探究不同流速、粒徑、孔喉條件下元素硫顆粒微觀運(yùn)移沉積規(guī)律。通過研究,取得了以下相關(guān)認(rèn)識:(1)應(yīng)用掃描電鏡觀測析出的硫顆粒微觀形態(tài),其粒徑分布主要在0-2μm之間,類比冰晶的分布規(guī)律,認(rèn)為硫顆粒粒徑在地層中服從Log-Normal分布;應(yīng)用掃描電鏡和壓汞法實驗手段,研究了高含硫氣藏巖心孔喉分布特征,孔隙半徑大小主要分布在1～20μm,平均中值半徑16μm。(2)在經(jīng)典的Hertz-Mindlin(no-slip)模型基礎(chǔ)上,建立考慮粘結(jié)力的接觸模型來描述元素硫顆粒的結(jié)晶、團(tuán)聚過程,模擬結(jié)果表明:元素硫顆粒之間粘結(jié)數(shù)量隨時間增大而增加,元素硫顆粒平均粒粒徑會增大,其分布曲線的概率密度函數(shù)峰值會變小。(3)單個硫顆粒在多孔介質(zhì)中的運(yùn)移主要受重力、浮力、曳力控制,低氣流速度條件下,硫顆粒的沉積主要為重力沉積和碰撞沉積;高速條件下,硫顆粒的運(yùn)移主要受到流體曳力控制,隨氣流流出多孔介質(zhì)而不產(chǎn)生沉積。(4)元素硫顆粒運(yùn)移沉積規(guī)律:對于同一粒徑的硫顆粒而言,其沉積率隨著氣流進(jìn)口速度增大而減小;對于同一氣流進(jìn)口速度而言,其沉積率隨著顆粒直徑增大而增大,因為較小粒徑硫顆粒基本處于懸浮狀態(tài),沉積率一般都很小,而大粒徑硫顆粒受重力作用影響比較大,更易發(fā)生沉積現(xiàn)象。還發(fā)現(xiàn)顆粒直徑對沉積率影響的程度大于氣流進(jìn)口速度對沉積率影響的程度。(5)模擬研究不同多孔介質(zhì)物理模型發(fā)現(xiàn),相同條件下,單孔雙喉的沉積率大于單孔孔三喉;雙孔三喉中,前一個孔隙比后一個孔隙沉積多;復(fù)雜多孔介質(zhì)沉積率最大;沉積元素硫顆粒的運(yùn)移滲流通道越曲折復(fù)雜,其元素硫顆粒在運(yùn)移過程其沉積率會明顯增大。
[Abstract]:The gas reservoirs with high sulfur content are widely distributed in the world. With the change of temperature and pressure, phase change will take place in the gas well production, and simple sulfur will be released from the gas. When the simple sulfur can not be carried away by the gas, the phenomenon of sulfur deposition will occur and the pore throat will be blocked. Damage formation, seriously affect the productivity of high sulfur gas wells. At present, the mechanism of sulfur deposition is mainly studied by macroscopical experiments and theories. The microscopic migration and deposition mechanism of elemental sulfur particles is not well understood, so it is necessary to adopt micro-scale research methods. Therefore, the mechanism of microscopic migration and deposition of elemental sulfur particles is simulated by gas-solid coupling method from a microscopic perspective, with emphasis on the gravity and drag force in the transport of elemental sulfur particles. The buoyancy and the adhesion of sulfur particles in the process of colliding clusters are analyzed, and the microcosmic migration and deposition of elemental sulfur particles under different velocity of flow, particle size and pore throat are studied. Through the research, the following relative knowledge is obtained: 1) the microscopic morphology of sulfur particles is observed by scanning electron microscope. The particle size distribution is mainly between 0 and 2 渭 m. Compared with the distribution law of ice crystal, it is considered that the particle size of sulfur particles is distributed from Log-Normal in the strata. The characteristics of pore throat distribution in high sulfur gas reservoirs are studied by means of scanning electron microscope and mercury injection method. The pore radius is mainly distributed in 1 ~ 20 渭 m and the mean median radius is 16 渭 m 路m ~ (-2) based on the classical Hertz-Mindlinno-slip model. A contact model considering adhesion is established to describe the crystallization and agglomeration process of elemental sulfur particles. The simulation results show that the amount of bonding between elemental sulfur particles increases with time, and the average particle size of elemental sulfur particles increases. The peak value of probability density function of its distribution curve will become smaller. (3) the migration of single sulfur particles in porous media is mainly controlled by gravity, buoyancy, drag force, and the deposition of sulfur particles is mainly gravity deposition and collision deposition under the condition of low airflow velocity. At high speed, the transport of sulfur particles is mainly controlled by fluid drag, and no deposition of sulfur particles is produced by flowing out of porous media with the flow: for sulfur particles of the same diameter, the sulfur particles of the same size are transported and deposited. For the same inlet velocity, the deposition rate increases with the increase of particle diameter, because the smaller sulfur particles are suspended, and the deposition rate is generally very small. However, the large diameter sulfur particles are affected by gravity more easily. It is also found that the influence of particle diameter on deposition rate is greater than that of airflow inlet velocity. (5) the physical models of different porous media show that the deposition rate of single pore and double throat is higher than that of single pore triple throat under the same conditions. In the twin-pore three-throat, the former pore is more than the latter; the deposition rate of complex porous media is the largest; the more complicated the migration and percolation channel of the deposited elemental sulfur particles, the higher the deposition rate of elemental sulfur particles in the migration process.
【學(xué)位授予單位】：西南石油大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：TE31

【相似文獻(xiàn)】

相關(guān)碩士學(xué)位論文 前3條

1 曹明雷;股流作用下鐵礦砂坡面侵蝕特征研究[D];山西農(nóng)業(yè)大學(xué);2015年

2 唐登濟(jì);高含硫氣藏元素硫顆粒運(yùn)移規(guī)律研究[D];西南石油大學(xué);2017年

3 李圣一;基于DEM的鉆井液振動篩顆粒運(yùn)移特性研究[D];西南石油大學(xué);2017年

，

本文編號：1789534