脱蜡油溶剂回收系统核算与优化.doc

脱蜡油溶剂回收系统核算与优化一、前言: 本课题以茂石化公司南方高级润滑油公司重质脱蜡油回收系统工艺过程为基础，进行系统的物料、能量及部分设备的工艺核算，为装置技术革新、工艺改造提供理论依据。 系统油品：轻质减压馏份(减二或减三含蜡油) 系统所用溶剂：甲苯、丁酮(甲基乙基酮) 溶剂回收系统的目标是： 以最少的热量回收所有的溶剂; 并保证脱蜡油不含溶剂。 溶剂回收系统的原理过程：过滤所得的滤液(脱蜡液)，经回收冷量后，进入本系统之后，经换热系统加热进入三效蒸发系统的低压塔，蒸出部分溶剂；塔底液体经泵增压后再经换热，进入中压塔，蒸出部分溶剂；塔底液体经加热炉加热，送入高压塔，进一步回收溶剂。高压塔底油中还含有少量的溶剂，直接压送到闪蒸塔，蒸出少量的溶剂；闪蒸底油自流至汽提塔中，经水蒸汽或氮气汽提。闪蒸塔底得不含溶剂的脱蜡油，经换热冷却送出装置。前四个塔顶的溶剂均为干溶剂，经换热、冷却后合并返回结晶系统循环使用；汽提塔回收的溶剂若以水蒸汽汽提则为含水溶剂，需进一步回收，此处不加以叙述。二、原始基础数据系统工艺流程示意图见附-1系统工艺操作及系统设备结构参数，取自现场标定数据。 装置物料平衡:入 方出 方项目流量kg/h百分率%项目流量kg/h百分率%原料油21545100脱蜡油887341.2含油蜡1267258.8合计21645100合计21545100脱蜡油性质数据项目单位测定值相对密度0.8852比色3.5粘度40 mm2.s-1143.0100 mm2.s-114.41闪点(开口)280凝点-4.9残炭%0.13酸值mgKOH/g0.029溶剂含量%微量苯胺点115.4馏程HK4142%46910%50530%53450%54570%56090%575 溶剂组成 项目采样地点相对密度溶剂含量%(重)溶剂组成水丁酮甲苯装置进料0.839584.900.2752.6147.12塔501顶0.823699.40.4760.5438.87塔501底0.845080.210.1547.3452.52塔502顶0.83100.3355.9543.71塔502底0.856968.760.0734.8965.04塔503顶0.84350.1238.7161.18塔503底0.88237.4塔504顶塔504底0.88254.0塔505底0.88450.017塔类操作数据设备进料温度塔顶温度塔底温度塔顶压力塔5011091080.08塔5021301290.16塔5032052032040.26塔5042041961980.01塔505198174188-0.01加热炉:滤液进炉温度128,计出炉温度206过热蒸汽: 750kg/h, 进炉温度135, 出炉温度343燃料气温32,烟气温度247换热器设备名称换热器型号介质程别温度面积换512FA700-160-16-4热T501顶剂二次壳程10860160冷滤液管程2950换513FB900-240-16-4热T501顶剂一次壳程108107240冷滤液管程5084换514/1FB-600-90-16-2热T503顶剂三次壳程1199390冷滤液管程8492换514/2FB600-90-16-2热T503顶剂二次壳程14911990冷滤液管程92104换515/1.2FB900-240-16-4热T502顶剂一次壳程129114240*2冷滤液管程104109换516FA700-160-16-4热T505油一次壳程188122160冷T501底滤液管程108122换517FLA1000-345-16-4热T503顶剂一次壳程202146345冷T501底滤液管程122130机泵数据流程号泵名称介质流量m3/h介质温度压力KPa电流A进口出口额定电流实际电流电压泵507滤液泵68.215-1320160014185393泵518塔501底52.30110815012005638393泵519炉进料泵35.501129230170013134393泵521脱蜡油泵12.001865010002618.8393数据来源说明：1、 该数据来自94年8月23日装置实际操作数据2、 脱蜡装置处理原料为大庆减四线糠醛精制馏分油，产品作为白土精制原料。3、 脱蜡装置处理量为：517.9吨/天，其中蜡液脱蜡油收率为8873kg/小时三、物料平衡、能量平衡、工艺计算1、 装置物料平衡 流量单位kg/h 物 流 甲苯 丁酮 油 水 入 脱蜡液 23510.0 26255.0 8875.0 135.0 汽提水蒸汽 430.0 方 合 计 23510.0 26255.0 8875.0 565.0 脱蜡油 8874.3 出 T201顶 4206.7 9619.0 0.1 120.3 T202-1顶 6880.7 10046.5 0.1 14.0 T202-2顶 11786.7 6495.4 0.2 0.7 T203顶 412.1 83.1 0.1 T204顶 223.8 11.0 0.2 430.0 方 合 计 23510.0 26255.0 8875.0 565.0 装置物料及单体设备物料平衡略2、装置能量平衡 装置能量平衡及单体设备能量平衡略3、装置设备工艺核算 主要校验换热器传热面积略四、计算结果分析 1、产品质量影响因素分析 - 水蒸汽汽提 T204为汽提塔，汽提蒸汽用量增大，产品含溶剂越少，质量越高，水蒸汽汽提，产生含水溶剂，对结晶系统产生不良影响，溶剂回收困难。 - 干式蒸馏 经灵敏度分析，干式闪蒸除溶剂效果较差， 在197，10KPa时，产品中含甲苯21kg/h 4KPa时，产品中含甲苯8.5kg/h - 氮气汽提 197度，50kg/h 氮气时，产品含甲苯2.8kg/h 150kg/h 0.05kg/h 270kg/h 0.001kg/h2、能耗影响因素分析 塔202-1压力对装置能耗灵敏度分析 T202-1 炉负荷 T2021顶 T2022顶 T202-1 压力KPa cal/sec. 流量kg/h 流量kg/h 顶温 195 6.731+05 1.958+04 1.560+04 117 202 6.790+05 1.926+04 1.592+04 119 210 6.847+05 1.895+04 1.624+04 120 218 6.901+05 1.865+04 1.655+04 121 226 6.954+05 1.835+04 1.685+04 123 233 7.004+05 1.806+04 1.714+04 124 241 7.054+05 1.777+04 1.744+04 125 249 7.101+05 1.749+04 1.772+04 126 257 7.147+05 1.721+04 1.800+04 127 265 7.192+05 1.694+04 1.828+04 129 五、结论1、产品质量 干式闪蒸不能满足产品质量要求 水蒸汽汽提可保证产品质量，但产生含水溶剂。 氮气气提既可保证产品质量，又不产生含水溶剂。2、装置能耗 T202-1压力对能耗影响较大， 压力越高，能耗越高。 保证T201进料有足够换热温差，尽可能降低T202-1操作压力。 T202-2压力对装置能耗影响较小 炉出口温度：195 -210。 Abstract:Computing and Optimizing Energy of the System of Dewaxing Oil Recovery All lube stocks, except those from a relatively few highly naphthenic crude oils, must be dewaxed or they will not flow properly at lower temperatures. Dewaxing is one of the most important and most difficult processes in lubricating oil manufacturing. Solvent dewaxing processes uses refrigeration to crystallize the wax and solvent to dilute the oil portion sufficiently to permit rapid filtration to separate the wax from the oil. The most widely used solvent dewaxing processes adopt mixtures of methylethylketone (MEK) and toluene as a solvent, while MEK is the extractive agent, toluene a solvent. The whole solvent dewaxing process is very large and complicated, including crystallizing system, vacuum filtering system, refrigeration system, and recovery system and secure gas system, etc. The oil recovery system is the most important in the recovery system, as shown in figure 5. The system consists of three stage flash tower (T201, T202, T202/1), furnace (F201), flash tower (T203), stripper (T204) and cooling and heat exchanging system.A great deal of Energy is needed in the recovery system. In order to recovering the energy, the system of three stages flash and heat exchanging is used. It should be assured that the system work good, or fuel is increased more, therefor, we must compute and optimize the process and energy of the system.计算过程 ASPEN PLUS IS A TRADEMARK OF HOTLINE: TBDEWAXXOIL TABLE OF CONTENTS COMPUTATIONAL SEQUENCE - SEQUENCE USED WAS: $OLVER10 T202-1 E224-1,2 T201 E223-1,2 E223 P223 P224 F201 T202-2 T203 | T204 E224-3,4 E224-5,7 E223-3 E224 (RETURN $OLVER10) OVERALL FLOWSHEET BALANCE - * MASS AND ENERGY BALANCE * IN OUT RELATIVE DIFF. CONVENTIONAL COMPONENTS (KMOL/HR ) TOLUE-01 255.154 255.154 -0.511997E-07 METHY-01 364.109 364.109 -0.119326E-06 WATER 31.3724 31.3724 -0.257796E-07 PC411C 0.252534E-01 0.252534E-01 0.315986E-12 PC420C 0.785524E-01 0.785524E-01 0.205113E-12 PC441C 0.156287 0.156287 0.618025E-13 PC473C 0.357721 0.357721 0.806935E-14 PC496C 0.540711 0.540711 0.246392E-14 PC525C 0.538645 0.538645 0.618343E-15 PC555C 1.13816 1.13816 0.195091E-15 PC580C 3.68215 3.68215 0.482424E-15 PC608C 3.05894 3.05894 0.299791E-12 PC633C 2.46347 2.46347 0.118888E-11 PC650C 0.183207 0.183207 0.220884E-12 TOTAL BALANCE MOLE(KMOL/HR ) 662.858 662.859 -0.864742E-07 MASS(KG/HR ) 59205.0 59205.0 -0.734928E-07 ENTHALPY(CAL/SEC ) -0.801030E+07 -0.729015E+07 -0.899021E-01 ASSAY DATA ANALYSIS - ASSAY ID: DEWAXOIL SPECIFIC GRAVITY 60F/60F 0.8852 API GRAVITY 28.3508 DENSITY GM/CC 0.8829 MOLECULAR WEIGHT MISSING DISTILLATION CURVES - PERCENT DISTILLED VERSUS TEMPERATURE, C ASTM PERCENT D86 TBP DISTILLED LV PCT LV PCT - - - 0 414.0 408.4 5 482.5 493.1 10 505.0 532.2 30 534.0 575.7 50 545.0 593.9 70 560.0 615.8 90 575.0 635.8 95 582.2 643.7 100 589.4 651.6 PRES KPA 101.3 101.3 PSEUDOCOMPONENT BREAKDOWN - ASSAY ID: DEWAXOIL MOLE WEIGHT VOLUME COMPONENT PERCENT PERCENT PERCENT - - - - PC411C 0.2066 0.1191 0.1286 PC420C 0.6426 0.3828 0.4116 PC441C 1.2786 0.8188 0.8717 PC473C 2.9266 2.0872 2.1896 PC496C 4.4236 3.3992 3.5296 PC525C 4.4067 3.6995 3.7950 PC555C 9.3115 8.5473 8.6602 PC580C 30.1245 29.7155 29.8063 PC608C 25.0259 26.5831 26.3857 PC633C 20.1542 22.8717 22.4866 PC650C 1.4988 1.7753 1.7345 PSEUDOCOMPONENT PHYSICAL PROPERTIES - PSEUDOCOMPONENT PROPERTY SUMMARY COMPONENT NBP API SG MW TC PC C C KPA PC411C 410.5590 41.1341 0.8196 418.7472 553.6148 969.8831 PC420C 419.7259 40.3694 0.8233 432.5310 561.4516 950.2038 PC441C 440.6318 38.6748 0.8315 465.0142 579.2118 907.7088 PC473C 472.8325 36.1901 0.8438 517.8418 606.2736 848.1094 PC496C 496.0323 34.4869 0.8524 557.9318 625.5600 809.0595 PC525C 524.6246 32.4798 0.8629 609.5547 649.0976 764.8631 PC555C 554.7980 30.4630 0.8736 666.4959 673.6715 722.3846 PC580C 580.2118 28.8390 0.8825 716.2300 694.1669 689.5401 PC608C 607.5250 27.1640 0.8918 771.2664 715.9968 656.9016 PC633C 633.0658 25.6592 0.9003 823.9883 736.2320 628.6233 PC650C 650.2616 24.6775 0.9060 860.0438 749.7620 610.6966 TBDEWAXXOIL BLOCK: E223 MODEL: HEATX - * MASS AND ENERGY BALANCE * IN OUT RELATIVE DIFF. TOTAL BALANCE MOLE(KMOL/HR ) 824.748 824.748 0.000000E+00 MASS(KG/HR ) 72721.5 72721.5 0.000000E+00 ENTHALPY(CAL/SEC ) -0.988004E+07 -0.988004E+07 0.000000E+00 * INPUT DATA * FLOW DIRECTION AND SPECIFICATION: COUNTERCURRENT HEAT EXCHANGER SPECIFIED COLD OUTLET TEMP SPECIFIED VALUE C 50.0000 LMTD CORRECTION FACTOR 1.00000 PRESSURE SPECIFICATION: HOT SIDE PRESSURE DROP KPA 0.0000 COLD SIDE OUTLET PRESSURE KPA 220.0000 DUTY AND AREA: CALCULATED HEAT DUTY CAL/SEC 159688.2823 CALCULATED (REQUIRED) AREA SQM 13.8898 HEAT TRANSFER COEFFICIENT: AVERAGE COEFFICIENT (DIRTY) CAL/SEC-SQCM-K 0.0229 LOG-MEAN TEMPERATURE DIFFERENCE: LMTD CORRECTION FACTOR 1.0000 LMTD (CORRECTED) C 50.2958BLOCK: E223-1,2 MODEL: HEATX * MASS AND ENERGY BALANCE * IN OUT RELATIVE DIFF. TOTAL BALANCE MOLE(KMOL/HR ) 824.748 824.748 0.000000E+00 MASS(KG/HR ) 72721.5 72721.5 0.200105E-15 ENTHALPY(CAL/SEC ) -0.944680E+07 -0.944680E+07 0.000000E+00 FLOW DIRECTION AND SPECIFICATION: COUNTERCURRENT HEAT EXCHANGER SPECIFIED COLD OUTLET TEMP SPECIFIED VALUE C 84.0000 LMTD CORRECTION FACTOR 1.00000 PRESSURE SPECIFICATION: HOT SIDE PRESSURE DROP KPA 0.0000 COLD SIDE OUTLET PRESSURE KPA 215.0000 DUTY AND AREA: CALCULATED HEAT DUTY CAL/SEC 273544.6548 CALCULATED (REQUIRED) AREA SQM 37.7271 HEAT TRANSFER COEFFICIENT: AVERAGE COEFFICIENT (DIRTY) CAL/SEC-SQCM-K 0.0201 LOG-MEAN TEMPERATURE DIFFERENCE: LMTD CORRECTION FACTOR 1.0000 LMTD (CORRECTED) C 36.0089 PRESSURE DROP: SHELLSIDE, TOTAL KPA 0.0000 TUBESIDE, TOTAL KPA 5.0000 * ZONE RESULTS * ZONE HEAT TRANSFER AND AREA: ZONE HEAT DUTY AREA DTLM AVERAGE U CAL/SEC SQM C CAL/SEC-SQCM-K 1 706.822 0.1459 23.8650 0.0203 2 272837.832 37.5812 35.7600 0.0203 BLOCK: E223-3 MODEL: HEATX - * MASS AND ENERGY BALANCE * IN OUT RELATIVE DIFF. TOTAL BALANCE MOLE(KMOL/HR ) 857.020 857.020 0.000000E+00 MASS(KG/HR ) 77058.4