20102-设计文档集0-Abstract

100,000 tons/year isobutylene resource utilization project - project summaryChapter 1Project Feasibility1.1 Project Policy Compliance Analysis1.1.1 Analysis of industrial policy compliance The Industrial Structure Adjustment Guidance Catalogue (2015) does not restrict any content related to this project, so it is not a restricted project.Reference basis: Industrial Structure Adjustment Guidance Catalogue (2015).According to the Industrial Structure Adjustment Guidance Catalogue (2015), there is no restriction on any content related to this project, so it is not a restricted project, so it is in line with the industry access policy.1.1.2 Analysis of the conformity of the development plan of the location or the parkThe project site is selected in Zhejiang Ningbo Petrochemical Economic and Technological Development Park. It is the only petrochemical and chemical industry development zone in Zhejiang Province with a total planned area of 40 square kilometers.The park has the largest public liquid chemical terminal in the country, with an annual handling capacity of over 10 million tons. It has the largest refining and chemical integration enterprise in the country, Zhenhai Refining, with 23 million tons / year crude oil processing capacity and 1 million tons / year ethylene cracking. Device. The project consists of methyl t-butyl ether ( MTBE ) in a two-step process of 140,000 tons / year of high purity methyl methacrylate ( MMA ), in line with the development plan of Ningbo Petrochemical Economic and Technological Development Park.1.2 Product planThe project uses the MTBE produced by the mixed carbon four produced by Zhenhai Refinery and Chemical Plant to produce high-purity isobutylene and then synthesizes methyl methacrylate in two steps. The product scheme is shown in Table 1-1 .Table 1-1 Product plan and specifications of this projectproduct nameAnnual productionlevelusePriceHigh purity methyl methacrylate136,000 tonsSuperior gradeSales25000Industrial grade methacrylic acid11,000 tonsIndustrial gradeSales200001.3 The amount and source of raw materials and auxiliary materialsThe main raw materials and auxiliary raw materials used in this project and power consumption are shown in Table 1-2 and Table 1-3, respectively.Table 1-2 List of main raw materials and auxiliary materialsprojectnameunitQuantitysourceMode of transportraw materialMethyl tert-butyl ether10,000 tons / year15.96Provided by the factoryPipeline transportation from the main plantair10,000 tons / year157.738From the atmospherecatalystTon / year22.4OutsourcingRoad and rail transportationExcipientProcess soft water10,000 tons / year3.738Provided by the factoryPipeline transportation from the main plantsuperheated steam10,000 tons/ ear11.102Provided by the factoryPipeline transportation from the main plantTable 1-3 List of utility consumptionNumberingMaterial nameunitconsumptionWay of usesource1Living watert/h2Continuous useGeneral factory2Recycled watert/h1568Continuous useGeneral factory3Softened watert/h12Continuous useGeneral factory4frozen watert/h254Continuous useGeneral factory5High pressure steamKg/h10000Start work 6Medium pressure steamKg/h2400Continuous use 7Low pressure steamKg/h9300Continuous use 8Low pressure steamKg/h7200Continuous use 9Hot watert/h10Continuous use 10ElectricitykW450Start 1100 11NitrogenNm3/h20Intermittent 600 12Instrument airNm3/h360Continuous use 13Power airNm3/h300Intermittent 1.4 Total Investment EstimateTable 1-4 Total Investment EstimationNumberingprojectFunds/10,000 yuan1Fixed assets fee15877.152Intangible assets76503Deferred assets632.474Total reserve fee2091.545Construction period loan interest1185.86Liquidity2699.12Total investment in the project30136.08Chapter II Project Introduction2.1 OverviewThis project is a deep processing project for methyl tert-butyl ether (MTBE) produced by Sinopec Zhenhai Refining & Chemical Co., Ltd. using the FCC and ethylene plant produced by the FCC and ethylene plant . Sinopec Zhenhai Refining & Chemical Co., Ltd. Has 23 million tons / year crude oil processing capacity and 1 million tons/year ethylene cracking unit.This project produces 140,000 tons / year high purity methyl methacrylate (MMA)from methyl tert-butyl ether (MTBE) in two steps .The project flow chart is shown in Figure 2-1Figure 2-1 project flow chart2.2 High purity isobutylene preparation process selectionAfter investigation, the isobutylene produced by Zhenhai Refinery Plant is mainly found in mixed carbon four, while mixed carbon four is mainly produced from FCC unit and ethylene unit, and the isobutylene component is used to produce methyl tert-butyl ether (MTBE).Since the boiling points of the components in the mixed C4 are similar, especially the boiling point of isobutylene and 1 -butene is closer ( isobutylene: -6.9C, 1 butene: -6.3 C ) , the relative volatility of the two is 1.022, and the precision separation requires 374. Block theory plates are difficult to achieve industrially, so industrial separation of isobutylene is basically carried out by chemical methods.The widely used chemical methods mainly include sulfuric acid absorption method, catalytic water law, tert-butanol method, MTBE cracking method, and isomerization method. Since the mixed carbon four of Zhenhai Refining & Chemical Plant is used to produce MTBE , and the demand for MTBE is decreasing year by year, the use of the existing MTBE plant to produce high-purity isobutylene can save a lot of equipment investment, so Zhenhai Refinery For the general plant, MTBE cracking to produce high-purity isobutylene is the best solution.2.3 methyl methacrylate synthesis process selectionThe worlds industrialized MMA production technologies include the acetone cyanohydrin method ( ACH method), the isobutylene oxidation method ( i-C4method), the ethylene method ( BASF method), the methyl methacrylate method, and the modified acetone cyanohydrin method ( MGC method), in which acetone cyanohydrin method and isobutylene oxidation method are the most important MMA production processes in the world .The isobutylene is oxidized by air in the presence of a molybdenum catalyst to form methacrylic acid, which is then esterified with methanol to obtain a product. The method is characterized by high catalyst activity, good selectivity, long life and high yield of methacrylic acid. The method is non-polluting, the source of raw materials is extensive, and the cost is lower than the acetone cyanohydrin method, but the process is complicated. Among the several routes for the preparation of MMA by isobutylene oxidation , the following industrializations are mainly used in the following two routes: the first route, referred to as the two-step oxidation method, that is, the gas phase catalytic oxidation of isobutylene or tert-butanol to methacrolein ( MAL ), the catalytic oxidation of methacrolein to methacrylic acid ( MAA ), followed by esterification of methacrylic acid with methanol under the action of a catalyst to form MMA .The route was first developed in 1982 by the Japanese Catalyst Chemical Company for nearly 20 years of research and development , and has now matured. The utility model has the advantages of fully utilizing the C4 fraction rich in raw materials and reducing environmental pollution, but also has the disadvantages of many equipments, complicated processes, use of corrosive sulfuric acid, and short catalyst life and low overall yield of the catalyst used in the acid-making step.The second route, referred to as direct methylation, ie, isobutylene or tert-butanol is catalytically oxidized to MAL , and MAL is further oxidatively esterified to MMA . This route was first developed and tested by Asahi Kasei Corporation of Japan. The process does not pass the methacrylic acid step, effectively avoids side reactions such as methacrylic acid polymerization, has high atomic economy and simple equipment, and is one of the most attractive MMA production processes in the world today.This project uses the direct methylation method of Asahi Kasei Corporation of Japan.27100,000 tons/year isobutylene resource utilization project - project summaryChapter III Introduction to Process FlowAccording to the requirements of green technology, the project implements the principle of energy saving and emission reduction and improving economic benefits. The innovative design of process raw materials and process modules has been carried out. Based on this, technology integration has been carried out to compare the processes involved in each section. , condition optimization, full process simulation and energy matching. The whole process of the plant is shown in Figure 3-1 .Figure 3-1 Full Process Simulation100,000 tons/year isobutylene resource utilization project-project summary3.1 MTBE cracking sectionThe raw material methyl tert-butyl ether was transported by pump from the Zhenhai Refinery Organic Synthesis Plant methyl tert-butyl ether storage tank and heated by a heat exchanger (H101) to 80C.After mixing with the isobutylene de-weighting column (T102) in a certain ratio, it enters the ether treatment tower preheater (H102).After heating, it enters the cracking reactor (R101).In the cleavage reactor (R101), methyl tert-butyl ether is cleaved under the catalysis of a solid acid catalyst to form isobutylene and methanol, and corresponding side reactions occur simultaneously.The reaction cracking gas is discharged from the lower discharge port of the cracking reactor (R101), and then cooled by the methanol rectification bottom heater (H105), the ether preheater (H101), and the bottom of the cooling tower (H103) in the cooling absorption unit. The methanol was removed to obtain a crude isobutylene product.The reaction cracking gas entering the bottom of the de-MTBE tower (T102) and the spray liquid at the top of the cooling tower ( T104 ) are sufficiently contacted by a countercurrent manner, and most of the methanol gas in the reaction cracking gas is absorbed by the absorbent water to form an aqueous methanol solution.The methanol aqueous phase in the cooling tower (T104) is heated by the heat exchanger (H105) and then enters the feed plate of the methanol dehydration tower (T105). After rectification, the gas phase material at the top of the column is condensed by the condenser of the methanol dehydration column, and The methanol rectification column (T103) is condensed in the vapor phase of the top of the column, and the methanol is mixed and flows into the storage tank.The methanol dehydration tower wastewater is refluxed to the methanol dehydration tower (T105) for recycling.After the cracked gas is removed by methanol in a water washing tower (T104), it is taken out from the top of the water washing tower to obtain purified isobutylene, and the next step is to prepare MAL .3.2 Methacrolein synthesis sectionThe isobutene ( 201 ) produced in the first stage is mixed with the refluxed isobutylene (225), preheated by the gas exiting the reactor, and then heated to 380 degrees into the reactor.At the same time, industrial pure oxygen (204) was mixed with circulating nitrogen (214) and heated to 380 degrees to enter the reactor for reaction.The main and side reactions of the reactor areThe reactor gas is preheated for the raw material, then exchanged with the tower T201 bottom reboiler, and then exchanged with the tower T201 for heat exchange, and finally cooled to 5 degrees for gas-liquid separation. A small part of the gas phase is sent to the catalytic combustion unit of the third stage, and most of it is subjected to nitrogen circulation. The liquid phase is separated from the water phase by the oil-water separator, the methacrolein phase is rectified by the tower T201, and the methacrolein is produced at the bottom of the column, the top of the column is separated from the bottom of the tower by the T202 , and the top of the tower is distilled.Ether and nitrogen oxygen, etc. The overhead gas is cooled to obtain liquid dimethyl ether recovery and gaseous nitrogen oxygen emission.3.3 Methyl methacrylate synthesis sectionMethanol (301), methacrolein (222) and refluxing methanol and methacrolein (323) produced in the first two stages are mixed and cooled to 90 degrees, and industrial pure oxygen and circulating nitrogen gas are introduced into the reactor. reaction.The stream exiting the reactor is first cross-exchanged with the T303 feed stream and cooled to 5 degrees for gas-liquid phase separation.A small portion of the gas phase undergoes catalytic combustion, and most of it undergoes circulation.The liquid phase is subjected to liquid-phase separation. The methanol aqueous phase is rectified to recover methanol by rectification T303 , and the ester phase is discharged from the top of the column through the rectification column T301 to non-condensable gas and organic gas to the catalytic combustion device, and the liquid at the top of the column is refluxed with methanol and methacrolein. The bottom of the column is methyl methacrylate, by-product methacrylic acid and water. After passing through the pervaporation membrane separation S302 to remove water, and then through rectification T302 , the tower tops methyl methacrylate, and the bottom of the tower is methacrylic acid.Chapter IV saving design innovation4.1 Heat exchanger networkThrough the Aspen Energy Analyzer software, and then according to the pinch design method, the whole process heat exchange network is optimized to maximize the use of the internal energy of the process, reducing the consumption of utilities, thereby reducing operating costs and reducing production costs. The final determined heat exchange network is shown in the figure:Figure. 4-1 Optimization of heat exchanger network in the first stageFigure 4-2 Optimization of heat exchanger network in the second stageFigure 4-3 Optimization of heat exchanger network in the third stageUsing the Aspen Energy Analyzer manual heat exchange, the heat exchange network after heat integration is obtained. Although the heat exchange area is increased, the utility can be saved, and the number of heat exchange units is also reduced, which can save a lot of energy.4.2 Separation sequenceThe impact of separation sequence on energy consumption is considered in this project. Taking the separation of dimethyl ether as an example, in the first stage, the isobutylene content is much higher than the dimethyl ether content, at this time the distillation separation needs a large reflux ratio and treatment capacity. As two methyl ether is inert for the next stage of reaction, it can be separated in second sections. In the second stage, a large number of isobutylene is oxidized to Methacrolein with higher boiling point, and the separation capacity of isobutylene and dimethyl ether is greatly reduced, thus saving the separation energy consumption.After the relevant calculation, the specific energy saving comparison results are shown in table 3-1. Table 4-1 Comparison of energy consumption at different locations分离位置Comparison of processing capacity（kmol/h）Reflux ratio comparisonComparison of total energy consumption（kW）Energy saving（kW）First section242.38149.434192.59Second section11.766.3231.523979.07Chapter 5 Equipment Selection5.1 OverviewBased on the simulation results of Aspen Plus , the team designed the sulfur dioxide converter R0201, the preliminary distillation column T0101 and the heat exchanger E0112 in the process, including basic equipment design parameters and special internal components design.The process design, basic parameter design and mechanical strength check of the T0101-T0105 equipment in the process were carried out using SW6-2011 and Cup-Tower software . The process design, selection, basic parameter design and mechanical strength check of all heat exchangers were carried out using SW6-2011 and Aspen Energy Design and Rating . The reactor volume and reaction time simulations were performed using COMSOL Multiphysics 5.2 . In addition, pumps, blowers, compressors, storage tanks, buffer tanks, reflux tanks and other equipment were selected , and the strength check and weight calculation of the tanks, buffer tanks and reflux tanks were carried out using SW6-2011 .Figure 5-1 Simulating the volumetric reaction time of a heat exchanger using Comsol software5.2 New process equipment application innovation5.2.1 New olefin oxidation reactorThe oxidation reactor used in this project is a new type of tubular reactor (patent: a tubular reactor suitable for olefin oxidation, patent number CN107952400A ), which overcomes the prior art of tubular reactor In the process of preparing methacrolein, the heat is not properly controlled, which is likely to cause excessive temperature difference in the bed hotspot, which will have a negative impact on the catalyst life and reactor operation.Figure 5.2 New tube reactor diagramFigure 5.3 Reaction sleeve diagram Figure 5.4 New feed tube structure 11 -heater inlet pipe, 12- heater outlet pipe, 21- upper end, 22- lower end,23- material inlet, 24- material outlet, 3- reaction tube, 41- feed section, 42- open section, 43- hole44- cone, 45 -venturi nozzleThe patented new tubular heat exchanger has the following three innovations:1. Since the reaction gas isobutene reacts easily with oxygen, it is not suitable to contact for a long time to avoid a deep reaction. The reactor is provided with 44 cones and 45 venturi nozzles in the feed section of the 41 feed