FCC油浆组成结构特征对延迟焦化及后续加工的影响

从重油催化裂化外甩油浆性质、组成结构特征入手,借助热转化反应特性理论和经验公式,计算出重油FCC油浆经延迟焦化加工的焦炭收率达到40%以上。对比工业生产中延迟焦化装置掺炼FCC油浆前后产品收率,模拟出FCC油浆经焦化加工的产品分布,验证了此前计算的理论焦炭收率,核算出加工效益。就焦化装置和当前国家燃料油消费税政策而言,FCC油浆加工比作为商品外销经济效益好。但焦化装置掺炼油浆对重油催化裂化装置产品分布有不良影响,催化装置效益明显下降。综合焦化、催化两套装置的整体效益看,加工油浆是没有效益的。延迟焦化掺炼FCC油浆对产品质量、设备运行也造成一定的影响。     

我国焦化蜡油的组成和特性

延迟焦化是二次加工中重油轻质化的重要工艺过程 ,焦化蜡油作为焦化装置的中间馏份产物 ,通常约占焦化产品的 2 0 %～ 30 %。焦化蜡油一般用于二次加工装置如催化裂化、加氢裂化的原料。但由于焦化蜡油的裂化性能较差 ,并影响所产汽、柴油质量等问题 ,使其加工利用受到一定限制。因此 ,有必要对焦化蜡油的组成、结构进行较深入的了解 ,以便根据其特点选择合理的加工利用途径。1　我国焦化蜡油化学组成与结构特点1 1　焦化蜡油的元素组成焦化蜡油的元素组成及性质见表 1[1] 。由表 1可见 ,我国焦化蜡油中碳的质量分数一般在86 0 4 %～ 86 8…     

焦化蜡油、催化油浆做加氢裂化原料的研究

焦化蜡油和催化油浆若直接作为加氢裂化原料，蜡油中的焦粉含量及催化油浆中的催化剂细粉会滞留在加氢精制催化剂床层上结焦，沉积引起床层压降超高的情况发生。通过选择适宜的过滤器进行的过滤试验结果表明：经适宜精度过滤后焦化蜡油采用适当比例与减压蜡油混合则完全满足加氢裂化对原料的要求，加氢裂化装置掺炼焦化蜡油是完全可行的；随着滤芯孔径的减小，过滤后催化油浆中的固体物含量也会进一步降低，但过滤后催化油浆中Na和Ni的金属含量、残碳和密度仍无法满足加氢裂化对原料的要求。     

掺炼FCC油浆对延迟焦化装置的影响

分析了延迟焦化装置掺炼FCC油浆对装置工艺操作条件、焦化产品分布及质量的影响,对延迟焦化装置掺炼FCC油浆存在的问题进行了分析。结果表明:掺炼FCC油浆后,产品液体收率降低了1.8%,焦炭产率增加了2.0%,而且产品质量变差,炉管结焦趋势增加,分馏塔底过滤器焦粉沉积严重,装置能耗增加。为减小影响,应该做到以下几点:经延迟焦化加工之前,FCC油浆应过滤处理和有足够的沉降时间,使其催化剂粉末含量降到最低;为保证装置长周期运行,掺炼FCC油浆的比例应尽可能低;加强巡检,定期清洗和检测设备。     

延迟焦化装置掺炼FCC油浆的工业实践

中国石油化工股份有限公司洛阳分公司延迟焦化装置掺炼FCC油浆的比例稳定维持在10%以上,最高达到13.6%。掺炼FCC油浆后,延迟焦化装置的操作苛刻度降低,经济效益可观,每月可创效864万元;但石油焦和蜡油产品质量变差,石油焦挥发分质量分数下降1.25百分点,灰分质量分数上升0.15百分点,蜡油残炭质量分数上升1.19百分点,密度上升67 kg/m~3,装置燃料气、3.5 MPa蒸汽、电的单耗均上升;加热炉炉管和炉出口转油线结焦加剧,炉出口压力上升速率较掺炼油浆前增大0.015 MPa/月;出现了加热炉进料泵出口弯头、跨线阀、进料调节阀阀芯严重磨蚀等问题,装置安全运行风险急剧上升。针对存在问题提出了开展预知性维修、控制油浆固含量、进行设备材质升级、缩短检修周期、优化工艺流程等应对措施和建议。     

焦化蜡油结构族组成的预测

提供了焦化蜡油的部分物性分析数据,并对焦化蜡油的结构族组成进行了分析研究,提出了用焦化蜡油的碳氢原子比（Ｃ／Ｈ）、密度和折射率来预测焦化蜡油结构族组成的方法,并与ｎ ｄ Ｍ法进行了比较,结果表明该预测结果优于ｎ ｄ Ｍ法。     

不同基属FCC油浆中芳烃结构组成分析

为实现催化裂化(FCC)油浆的高附加值利用,研究了不同油浆窄馏分中芳烃的结构和组成变化。以中间基属和石蜡基属FCC油浆的抽出油为原料,采用实沸点减压蒸馏切割得到7个窄馏分,以改进的Brown-Ladner(B-L)法和全二维气相色谱/飞行时间质谱为表征手段,考察了2种油浆各窄馏分中芳烃的结构组成变化。结果表明：中间基属的青岛炼化催化裂化油浆(QD-FCC油浆)以3~5环芳烃为主,而石蜡基属的兰州炼化催化裂化油浆(LZ-FCC油浆)以2~4环芳烃为主,石蜡基属LZ-FCC油浆的总饱和碳及环烷碳分率大于中间基属QD-FCC油浆。2种油浆中三环芳烃主要是渺位缩合的菲类和氢化苯并蒽类化合物;四环芳烃以渺位缩合的苯并蒽类化合物为主,且含有部分迫位缩合的芘类化合物;五环芳烃以迫位缩合的苯并芘类化合物为主,石蜡基属LZ-FCC油浆中的五环芳烃含量远远小于中间基属QD-FCC油浆。     

几种焦化蜡油化学组成与结构的研究

测定了大庆、胜利、辽河、管输等5种焦化蜡油的密度、平均分子量、折光指数、元素和1H－NMR核磁共振波谱等数据，研究了5种焦化蜡油的化学组成，包括饱和烃、轻芳烃、中芳烃、重芳烃和胶质5个组分的含量，并与直馏蜡油的数据进行了对比；采用改进的B－L法、n－d－M法和密度法计算了平均结构参数。提出了焦化蜡油的芳碳率（CA％）、总环数（RT）与H／C原子比的数学关联式。     

FCC大比例掺炼焦化蜡油的催化剂管理

选用几种新型抗氮催化剂,根据装置情况合理混配,并通过有效的平衡剂管理等一系列措施,使得催化裂化装置的焦化蜡油掺炼比大幅度上升。     

Composition and Properties of Chinese Coker Gas Oil

The composition and properties of China coker gas oil are analyzed and studied. The factors of effecting on the reaction of coker gas oil and measures that should be adopted are discussed. Research results show that China coker gas oil contains 86.04-86.87% C and 11.96-13.72% H, with an H/C atom ratio of 1.7. China coker gas oil contains 51.1-68.3% of saturated hydrocarbon, 24.8-37.4% of aromatic hydrocarbon, 5.7-11.5% resin and no asphalt. The aromatic carbon rate is 14-20% and alkyl carbon rate is 58-71%. The total cycle number R_T is 2.1-2.5 and the aromatic cycle number R_A is 0.8-1.3, with R_A/R_N slightly more than 1. The nitrogen contents of China coker gas oil is a bit high, which is more than 0.35%, so denitrogen should be taken into account to enhance the blending ratio of coker gas oil in FCC feed.     

Composition and Properties of Chinese Coker Gas Oil

Abstract:

The composition and properties of China coker gas oil are analyzed and studied. The factors of effecting on the reaction of coker gas oil and measures that should be adopted are discussed. Research results show that China coker gas oil contains 86.04–86.87% C and 11.96–13.72% H, with an H/C atom ratio of 1.7. China coker gas oil contains 51.1–68.3% of saturated hydrocarbon, 24.8–37.4% of aromatic hydrocarbon, 5.7–11.5% resin and no asphalt. The aromatic carbon rate is 14–20% and alkyl carbon rate is 58–71%. The total cycle number R _T is 2.1–2.5 and the aromatic cycle number R _A is 0.8–1.3, with R _A /R _N slightly more than 1. The nitrogen contents of China coker gas oil is a bit high, which is more than 0.35%, so denitrogen should be taken into account to enhance the blending ratio of coker gas oil in FCC feed.     

Properties and Chemical Composition of Typical Coker Gas Oil

The coker gas oil from Daqing, Shengli, and Liaohe, which are three famous oil fields in China, are studied. The properties, chemical composition, and structural composition of coker gas oil from Daqing, Shengli, and Liaohe saturated hydrocarbon are analyzed. The results show that nitrogen and sulfur content in Daqing coker gas oil is the lowest, and saturated hydrocarbon content is the highest, and Daqing coker gas oil is the most easily processed raw material, and Liaohe coker gas oil mediates between two raw materials, but Shengli coker gas oil is the most difficult to process. By comparing with vacuum gas oil and nitrogen, sulfur content and carbon residue in the coker gas oils is higher and saturated hydrocarbon content is lower. Shengli coker gas oil is a somewhat inferior raw material. The factor of effecting on the processing and use of coker gas oil are analyzed, and the processing ways of coker gas oil are put forward.     

Properties and Chemical Composition of Typical Coker Gas Oil

Abstract

The coker gas oil from Daqing, Shengli, and Liaohe, which are three famous oil fields in China, are studied. The properties, chemical composition, and structural composition of coker gas oil from Daqing, Shengli, and Liaohe saturated hydrocarbon are analyzed. The results show that nitrogen and sulfur content in Daqing coker gas oil is the lowest, and saturated hydrocarbon content is the highest, and Daqing coker gas oil is the most easily processed raw material, and Liaohe coker gas oil mediates between two raw materials, but Shengli coker gas oil is the most difficult to process. By comparing with vacuum gas oil and nitrogen, sulfur content and carbon residue in the coker gas oils is higher and saturated hydrocarbon content is lower. Shengli coker gas oil is a somewhat inferior raw material. The factor of effecting on the processing and use of coker gas oil are analyzed, and the processing ways of coker gas oil are put forward.     

Characterization of Nitrogen Compounds in Vacuum Residue and Their Structure Comparison with Coker Gas Oil

In this study, the heteroatom classes and molecular structures of nitrogen compounds in vacuum residue are characterized by the electrospray ionization(ESI) Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS) combined with the Fourier transform infrared(FT-IR) spectroscopy. The results demonstrate that three basic nitrogen compounds, N1(in which a molecule contains one nitrogen atom, similarly hereinafter), N1O1 and N2, are identified by their positive-ion mass spectra, and three non-basic nitrogen compounds, N1, N1O1, and N1S1, are characterized by their negative-ion mass spectra. Among these nitrogen compounds, the N1 class species are the most predominant. Combined with the data of ESI FT-ICR MS and FT-IR, the basic N1 class species are likely alkyl quinolines, naphthenic quinolines, acridines, benzonacridines, while the abundant non-basic N1 class species are derivatives of benzocarbazole. In comparison with CGO, the N1 basic nitrogen compounds in VR exhibit a higher average degree of condensation and have much longer alkyl side chains.     

Hydrofining and Catalytic Cracking of Coker Gas Oil

Abstract

The hydrofining of coker gas oil (CGO) was investigated on catalyst RN-2 in a micro hydrogenation apparatus. High reaction temperature favors the desulfurization and denitrogenation for the hydrofining of CGO, but it disfavors the yield of total liquids. Desulfurization degree, denitrogenation degree, and the total yield of liquid products increase with the enhancement of reaction pressure. As the hydrogen-to-oil ratio increases, the desulfurization degree increases, and the denitrogenation degree shows a maximum at a hydrogen-to-oil ratio of 800. Catalytic cracking of CGO, hydrofined CGO, and vacuum gas oil (VGO) on catalyst LMC-500 was investigated in a pilot-scale fluid catalytic cracking (FCC) unit. The catalytic cracking performance of hydrofined CGO is better than that of CGO.     

煤焦油沥青质与减压渣油沥青质结构组成的对比

基于核磁共振氢谱(¹H-NMR)、核磁共振碳谱(¹³C-NMR)和傅里叶变换离子回旋共振质谱(FT-ICR MS),分析了煤焦油和减压渣油中正庚烷沥青质的结构和分子组成的差异。在大气压光致电离源(APPI)和电喷雾电离源(ESI)下,质谱测得的煤焦油沥青质相对分子质量分布范围均小于减压渣油沥青质,但其中含氧类化合物或其他含氧多杂原子相对丰度高于减压渣油沥青质。各类化合物中,煤焦油沥青质均含有更小等效双键数(DBE)的化合物;在相同DBE下,减压渣油沥青质的碳数分布范围更大,意味着减压渣油沥青质的烷基侧链分布范围宽。计算了煤焦油沥青质和减压渣油沥青质结构单元平均分子式分别为C_30.54H_26.57S_0.04N_0.54O _2.80和 C_42.41H_41.54S_0.85N_0.63O_0.48。煤焦油沥青质结构单元的芳香度较高,而芳环数和芳环缩合度均小于减压渣油沥青质。煤焦油沥青质中的低缩合度化合物能够对沥青质聚集体中芳环的堆积作用产生直接的影响,但影响程度仍需进一步研究。     

不同来源催化裂化柴油馏分中烯烃的组成与分布特点

采用Ag-SiO2固相萃取法结合全二维气相色谱-飞行时间质谱（GC×GC-TOF MS）相对大庆、胜利、辽河、塔河四种催化裂化柴油馏分中烯烃的组成特点进行了分析。烯烃的类型和碳数分布结果表明：胜利、辽河和塔河催化裂化柴油均由单烯烃、环烯烃、双烯烃、三烯或环二烯组成,均呈现单峰分布特点;大庆催化裂化柴油烯烃含量较低,仅检测出单烯烃和环烯烃系列。四种柴油烯烃中以单烯烃含量为最高,可占总脂肪烯的50%以上,但是正构α烯烃含量却都低于5%,说明催化裂化柴油中主要以内烯烃和异构烯烃为主。烯烃的类型和分布与加工过程的反应机理有直接关系,通过分子组成分析,能为油品加工工艺机理的研究提供方法支持。     

催化裂化柴油及其加氢产物中芳烃类型 与分子结构的表征

基于气相色谱-质谱(GC-MS)测定催化裂化柴油(LCO)及其加氢产物中芳烃的组成。根据色谱保留时间和质谱断裂特征,分析了LCO及其加氢产物中芳烃的类型与结构,并对C₉~C₁₁的C_nH_2n-8类及C_nH_2n-12类芳烃进行了分子结构鉴别。结果表明：C_nH_2n-8类芳烃在LCO中为具有五元环结构的茚满类,在加氢产物中既有四氢萘类,也有茚满类,后者可由前者发生异构化反应生成;C_nH_2n-10类芳烃在LCO中是以含有双键的环烷芳烃为主,如茚类、二氢萘类,在加氢产物中则是以含有饱和环结构的芳烃,如二环烷基苯类为主;LCO及其加氢产物中的C_nH_2n-16类芳烃均为芴类;萘类侧链的碳数、个数与位置均会影响其加氢转化率。此研究可为芳烃的选择性加氢以及后续加工提供信息。