当代化工
噹代化工
당대화공
CONTEMPORARY CHEMICAL INDUSTRY
2015年
2期
261-262,267
,共3页
韩洪升%李勇生%管庆安%陈欣
韓洪升%李勇生%管慶安%陳訢
한홍승%리용생%관경안%진흔
蜡晶%剪切应力%滞回环%屈服应力
蠟晶%剪切應力%滯迴環%屈服應力
사정%전절응력%체회배%굴복응력
Wax crystal%Shear stress%Hysteresis loop%Yield stress
含蜡原油的胶凝问题是管道运输过程中一个重要的研究问题。通过对经历不同降温速率温度降至凝点附近的原油做匀加速剪切,剪切至某值后再做匀减速剪切,形成一个环形剪切。测量剪切应力随剪切速率变化的曲线关系,结果表明:在这样循环匀变速剪切的作用下,样品的剪切应力各点连线也呈现一个环形,即称作含蜡原油的滞回环。在胶凝原油发生屈服之前,剪切应力随剪切速率增大急剧增大,持续的剪切会有效阻止蜡晶结构的形成;降温速率越低,原油形成的蜡晶结构强度越大。
含蠟原油的膠凝問題是管道運輸過程中一箇重要的研究問題。通過對經歷不同降溫速率溫度降至凝點附近的原油做勻加速剪切,剪切至某值後再做勻減速剪切,形成一箇環形剪切。測量剪切應力隨剪切速率變化的麯線關繫,結果錶明:在這樣循環勻變速剪切的作用下,樣品的剪切應力各點連線也呈現一箇環形,即稱作含蠟原油的滯迴環。在膠凝原油髮生屈服之前,剪切應力隨剪切速率增大急劇增大,持續的剪切會有效阻止蠟晶結構的形成;降溫速率越低,原油形成的蠟晶結構彊度越大。
함사원유적효응문제시관도운수과정중일개중요적연구문제。통과대경력불동강온속솔온도강지응점부근적원유주균가속전절,전절지모치후재주균감속전절,형성일개배형전절。측량전절응력수전절속솔변화적곡선관계,결과표명:재저양순배균변속전절적작용하,양품적전절응력각점련선야정현일개배형,즉칭작함사원유적체회배。재효응원유발생굴복지전,전절응력수전절속솔증대급극증대,지속적전절회유효조지사정결구적형성;강온속솔월저,원유형성적사정결구강도월대。
The problem of waxy crude oil gelling is an important research problem in the process of pipeline transport. In this experiment, uniformly accelerated shear of crude oil whose temperature was dropped to freezing point by different cooling rate was carried out; after the shear rate reached to the maximum value, uniform deceleration shear was carried out to form a cyclic shear. The relationship between the shear stress and shear rate change was measured. The results show that: under the action of such a cycle uniform variable shear, the attachment of each shear stress point of sample also presents a ring, which is called the hysteresis loop of waxy crude oil. Before the gelled crude oil yields, shear stress increases sharply with the increase of shear rate, and constant shear will effectively prevent the formation of wax crystal structure; the lower the cooling rate, the higher the wax crystal structure strength.