張 斌
(四川石化有限責(zé)任公司, 四川 成都 611930)
首套南疆渣油加氫裝置長周期運(yùn)行難點(diǎn)及對(duì)策
張 斌
(四川石化有限責(zé)任公司, 四川 成都 611930)
該套渣油加氫裝置為首套加工南疆油的渣油加氫裝置,由于南疆油中難溶瀝青質(zhì)含量較高,其轉(zhuǎn)化率較低,裝置分餾系統(tǒng)低溫部位易出現(xiàn)瀝青質(zhì)析出積垢,精制渣油外輸壓降增大,導(dǎo)致該裝置被迫降負(fù)荷生產(chǎn),換熱器結(jié)垢后精制渣油與原料油換熱器換熱效果下降,反應(yīng)加熱爐入口溫度下降,增加了反應(yīng)加熱爐的負(fù)荷,直接影響裝置長周期運(yùn)行,通過各種措施的有效實(shí)施,裝置運(yùn)行周期得到延長。
南疆油;難溶瀝青質(zhì);結(jié)垢;重回?zé)捰停婚L周期
Abstract:The VRDS unit is the first unit for processing southern Xinjiang oil. Due to high asphaltene content in southern Xinjiang oil, the conversion rate is low, low temperature part of the main fractionator system is prone to asphaltene precipitation fouling, refined oil pipeline pressure drop increases, resulting in the device to run under low load, heat transfer effect of heat exchanger of refined oil and crude oil decreases after fouling of heat exchanger,entrance temperature of reaction heating furnace decreases, which can increase the reaction furnace load and can directly affect long period operation of the unit. So various measures have been taken, the operation cycle of the residue hydrotreating unit has been extended.
Key words:Xinjiang oil; insoluble asphaltene; scaling; heavy cycle oil; long period
該套渣油加氫裝置處理能力300萬t/a,于2014年建成投產(chǎn),是全加氫煉廠的核心裝置。由于精制渣油與原料油換熱器、精制渣油蒸汽發(fā)生器及精制渣油空冷的管層堵塞,引起渣油外輸不暢,裝置只能降加工負(fù)荷生產(chǎn),甚至被迫單系列停工清理換熱器,裝置長周期運(yùn)行困難重重[1]。而換熱器管束結(jié)垢堵塞的情況在同類渣油加氫裝置極少發(fā)生,查找原因及尋找解決辦法可借鑒的經(jīng)驗(yàn)較少。
該裝置于原始開車運(yùn)行3月后,發(fā)現(xiàn)裝置精制渣油去催化裂化裝置排放不暢,出現(xiàn)了分餾塔液位無法正常控制的情況,而此時(shí)出裝置流量控制閥已100%全開,裝置被迫降量生產(chǎn),排查原因。
經(jīng)過分析裝置運(yùn)行狀態(tài),發(fā)現(xiàn)原料油與精制渣油換熱器E1003E1002換熱效果明顯下降,現(xiàn)場增加臨時(shí)換熱設(shè)備管層出入口就地壓力表,檢測發(fā)現(xiàn)換熱器壓降增大,高于設(shè)計(jì)值,說明換熱器堵塞。……