tailieunhanh - Giáo trình thuật ngữ chuyên ngành Dầu và Khí - Unit 3

CRUDE OIL DISTILLATION (FRACTIONATION) 1. Description The first step in the refining process is the separation of crude oil into various fractions or straight-run cuts by distillation in atmospheric and vacuum towers. The main fractions or "cuts" obtained can be classified in order of decreasing volatility into gases, light distillates, middle distillates, gas oils, and residuum. 2. Atmospheric Distillation Tower At the refinery, the desalted crude feedstock is preheated using recovered process heat. . | Giáo trình Thuật ngữ chuyên ngành Dầu và Khí 13 UNIT 3 CRUDE OIL DISTILLATION FRACTIONATION 1. Description The first step in the refining process is the separation of crude oil into various fractions or straight-run cuts by distillation in atmospheric and vacuum towers. The main fractions or cuts obtained can be classified in order of decreasing volatility into gases light distillates middle distillates gas oils and residuum. 2. Atmospheric Distillation Tower At the refinery the desalted crude feedstock is preheated using recovered process heat. The feedstock then flows to a direct-fired crude charge heater where it is fed into the vertical distillation column just above the bottom at pressures slightly above atmospheric and at temperatures ranging from 650 to 7000F heating crude oil above these temperatures may cause undesirable thermal cracking . The fractionating tower a steel cylinder about 120 feet high contains horizontal steel trays for separating and collecting the liquids. The trays permit the vapors to bubble through the liquid on the tray causing some condensation at the temperature of that tray. An overflow pipe drains the condensed liquids from each tray back to the tray below where the higher temperature causes re-evaporation. The evaporation and condensing operation is repeated many times until the desired degree of product purity is reached. FIGURE I. ATMOSPHERIC DISTILLATION. Giáo trình Thuật ngữ chuyên ngành Dầu và Khí 14 VOCABULARY atmospheric tmas ferlk khí quyển cause kũ z gây ra classify kl slfal phân loại condensation kDnden seựn sự ngưng tụ desalt dl sũ lt Khử muối distillation dlstl lelĩn chưng cất drain dreln rút tháo evaporation l v pa rel ĩ n sự bay hơi feedstock fl dstũk nguyên liệu fraction fr kfn phân số phân đoạn heater hl t9 lò furnace fa nls in order of theo light middle heavy Nhẹ Trung bình Nặng overflow pipe ouvaflou ống vách chảy chuyền preheat prl hl t đun nóng trước pressure preĩa r áp suất purity pjuaratl độ tinh khiết .