Table of Content

12 April 2023, Volume 54 Issue 4

Previous Issue    Next Issue

DEVELOPMENT AND APPLICATION OF PROPANE DEHYDROGENATION CATALYST PST-100

2023, 54(4):  1-7. 

Asbtract ( 245 )   PDF  

References | Related Articles | Metrics

Based on the Pt-Sn-M/Al2O3 system, propane dehydrogenation catalyst PST-100 for moving bed reactor was developed. The effects of promoter M and Cl content on the catalytic performance and coke deposition rate were investigated. The results showed that an appropriate amount of promoter M was helpful to reduce the acidity of the catalyst, especially the amount of medium strong acid, which was able to strengthen the synergistic effect of acid function and metal function, and reduced the coke deposition rate of the catalyst. An appropriate amount of Cl on the catalyst was conducive to the re-dispersion of Pt in the catalyst regeneration process resulting in the improvement of the activity stability. The results of 200 h simulated aging test and multiple regeneration tests showed that PST-100 catalyst had good hydrothermal stability and regeneration performance. The results of commercial application of 4a in a 450 kt/a unit of a company showed that the catalyst had excellent catalytic activity and activity stability.

EFFECT OF DIFFERENT VALENCE Ni ON GASIFICATION REACTION OF COKE ADHERING TO CONTACT AGENT

2023, 54(4):  8-14. 

Asbtract ( 121 )   PDF  

References | Related Articles | Metrics

In view of the influence of nickel deposited on the contact agent during residue contact cracking and coke gasification process, the effect of different valence nickel on the coke gasification reaction on the contact agent was studied. The nickel contaminants were analyzed by XRD, XRF, BET and TPR methods, and the effect of different valence nickel deposited on the contact agent on the coke gasification reaction was investigated in a small fixed fluidized bed device. The results showed that high-valence nickel (less than 2% by mass fraction) promoted the CO selectivity of coke gasification under oxygen-poor condition, but low-valence nickel had a negative effect on the CO selectivity. In the experiment of CO oxidation, the reaction of CO oxidation to CO₂ was inhibited by high valence nickel, but promoted by the low valence nickel. When the temperature reached 730 ℃, the CO oxidation reaction rate increased rapidly. Increasing the volume fraction of reactant O₂ promoted the formation of CO₂, while increasing the volume fraction of CO₂ had little effect on the n(CO)/n(CO₂) ratio of the product.

COMMERCIAL APPLICATION OF ENVIRONMENT-FRIENDLY MULTIFUNCTIONAL ADDITIVE PCA-101 IN CATALYTIC CRACKING UNIT

2023, 54(4):  15-18. 

Asbtract ( 136 )   PDF  

References | Related Articles | Metrics

Environment-friendly multifunctional additive PCA-101 was used in the 2.80 Mt/a catalytic cracking unit of PetroChina Huhhot Petrochemical Company. The results showed that the addition of PCA-101 did not cause pollution to the catalyst in the FCC unit. The antimony content in the equilibrium catalyst was reduced from 2 425 μg/g to 716 μg/g, and the waste catalyst was transformed from the dangerous waste to the solid waste. Moreover, the yield of light liquid increased by 0.49 percentage point, which effectively improved the product distribution. The volume fraction of hydrogen in dry gas decreased from 48.92% to 47.39%, which indicated that PCA-101 had a good effect of inhibiting Ni pollution.

RESEARCH ON PERFORMANCE OF LONG-CHAIN ALKANE DEHYDROGENATION CATALYST PREPARED BY ETHANOL-FREE METHOD

2023, 54(4):  19-23. 

Asbtract ( 98 )   PDF  

Related Articles | Metrics

The long-chain alkane dehydrogenation catalyst was prepared with water-ethanol as solvent in an industrial plant, and the effect of ethanol in the solvent was investigated. The catalysts were characterized by N₂ adsorption-desorption, X-ray diffraction, CO pulse chemisorptions, H₂-temperature programmed reduction and thermogravimetric analysis, and the performance of the catalyst was evaluated in a fixed bed reactor. The results showed that the catalysts prepared by ethanol-free solvent impregnation method had high Pt dispersion, dehydrogenation activity and good activity stability.

DEVELOPMENT AND APPLICATION OF HIGH SULFUR RESIDUE HYDROTREATING TECHNOLOGY FOR PRODUCING LOW SULFUR HEAVY MARINE FUEL COMPONENTS

2023, 54(4):  24-28. 

Asbtract ( 152 )   PDF  

References | Related Articles | Metrics

In the process of deep hydrodesulfurization (HDS) of high sulfur residue, the refractory sulfur-containing compounds were most difficult to remove because of side chain substitution and strong spatial position effect, and metal (Ni + V) and carbon deposition on catalysts were accelerated. The research on catalyst grading ratio of hydrodemetallization (HDM) catalyst and HDS&HDCCR catalyst for reducing carbon residue was carried out. The results showed that the HDM rate increased with the increase of the residence time of the reaction stream on the HDM catalyst, and the HDS rate increased with the increase of the residence time of the reaction stream on the HDS&HDCCR catalyst, but after reaching a certain residence time (inflection point value), the increasing trend obviously slowed down. The new HDS&HDCCR catalyst had low initial HDS activity, and the activity increased and remained stable with the extension of operating time. Based on the research results of the gradation and the characteristics of HDM&HDS catalyst, an advanced catalyst gradation technology for high sulfur residue deep HDS was developed and applied in the fixed bed residue hydrotreating unit. The results showed that the new technology had good HDS activity and excellent stability, and the fixed bed residue hydrotreating unit could stably produce blending components of low sulfur heavy marine fuel on the premise of ensuring the supply of FCC feedstocks.

CONFIGURATION OPTIMIZATION OF NEW PETROCHEMICAL COMPLEX

2023, 54(4):  29-36. 

Asbtract ( 294 )   PDF  

References | Related Articles | Metrics

Taking typical Saudi blended crude oil as the research object, this paper discussed the influence of different crude oil processing schemes on refining-chemical integration total processing flow through analyzing its composition, processing route and chemical raw material optimization. The results showed that the optimization of oil refining process and the production of chemical products could be coordinated under the principle of “appropriate olefins feedstock produces more olefins and appropriate aromatics feedstock produces more aromatics” in order to realize overall optimization of refining and chemical products production. In the new chemical refinery, the technology like DCC, RLA, C₄ process and normal and isomeric naphtha separation could improve the product structure, reduce the fuel oil production, and product more chemical raw materials and appropriate aromatic products. By optimizing the product scheme of refining and chemical integration, we can improve the whole plant economy, reduce the operating cost and enhance the enterprise competitiveness.

OPERATION ANALYSIS OF MIP-CGP UNIT PROCESSING HYDROGENATED GAS OIL

2023, 54(4):  37-42. 

Asbtract ( 106 )   PDF  

Related Articles | Metrics

The operation of 3 Mt/a hydrogenated gas oil (HVGO) MIP-CGP unit using HVGO as feed in Zhejiang Petrochemical Co., Ltd. was summarized and analyzed. The propylene content of liquefied petroleum gas produced by this unit was compared and analyzed by using MFP (FCC process for Marine Fuel and Propylene), MIP-CGP (Clean Gasoline and Propylene Production) and DCC (Deep Catalytic Cracking). The results showed that compared with the design value, the olefin mass fraction of the stabilized gasoline produced by MIP-CGP technology reached 15.9%, the research octane number reached 93.0, and the sulfur mass fraction was only 108 μg/g, which could be used as the high-quality raw material for producing high octane gasoline in S Zorb unit. The coke yield decreased by 0.64 percentage point, and the yield of liquefied petroleum gas increased by more than 3 percentage points, reaching a higher level of liquefied petroleum gas production by gas oil catalytic cracking. In view of the problem of the low olefin content of liquefied petroleum gas produced by HVGO MIP-CGP process, it was suggested that the MFP process should be used to improve the adaptability of the unit to increase the content of propylene and butylene in liquefied petroleum gas, and to reduce gasoline production.

STUDY ON ONLINE CLEANING TECHNOLOGY OF RESIDUE HYDROTREATING UNIT

2023, 54(4):  43-47. 

Asbtract ( 105 )   PDF  

References | Related Articles | Metrics

The effects of online cleaning on catalyst activity and reactor pressure drop by using catalytic cracking (FCC) light cycle oil (LCO), kerosene and FCC slurry was studied on a fixed-bed residue hydrotreating unit. Firstly, the residue hydrotreating unit in the middle stage of operation was cleaned online for 72 h by using LCO, the density, carbon residue value, sulfur mass fraction and metal content of the hydrotreated oil decreased significantly after cleaning, and the metal content could be kept at a low level for a long time. The pressure drop in fixed-bed reactor was simulated by raising the reaction temperature，and the unit was cleaned online by using kerosene and FCC slurry,respectively. When kerosene was used to clean the reactor, the pressure drop of the reactor would quickly rise again,while the pressure drop of the reactor did not rise after 500 h of operation by using FCC slurry.It was concluded that the increase of pressure drop caused by coking of catalyst could be solved by intermittent cleaning of high aromatic FCC slurry.

STUDY ON PRETREATMENT OF STRAIGHT-RUN DIESEL AND ITS STEAM CRACKING PERFORMANCE OPTIMIZATION

2023, 54(4):  48-53. 

Asbtract ( 100 )   PDF  

References | Related Articles | Metrics

In view of the current situation of the decreasing demand for diesel and the difficulty of diesel products leaving the factory, combined with the advantages of integrated refining and chemical unit, three processes, hydrofining, single-stage hydrocracking (SSOT) and adsorption dearomatization, were used to carry out the diesel pretreatment. The pyrolysis performance of three pretreated products was evaluated by the test equipment, and the coking performance of the products was also investigated. The results showed that the pyrolysis performance of diesel pretreated by SSOT and adsorption dearomatization process was significantly improved, which could be used as steam cracking feedstock, and adsorption dearomatization process had higher aromatics removal rate than the SSOT process. The yield of target olefin of the low aromatics fraction was significantly increased,while the yield of coke was remarkablely decreased. Optimization of pyrolysis furnace outlet temperature (COT) of low aromatics fraction after adsorption dearomatization pretreatment was carried out on a test set. The results of coking performance optimization test showed that, when the adsorption dearomatization low aromatic fraction was used as steam cracking raw material, the recommended COT was 830 ℃, and the recommended sulfide addition content was 200-300 μg/g.

TECHNICAL SELECTION AND INDUSTRIAL APPLICATION OF REVAMPING AN IDLE REFORMING NAPHTHA HYDROTREATING UNIT INTO A C₅/C₆ ISOMERIZATION UNIT

2023, 54(4):  54-60. 

Asbtract ( 115 )   PDF  

Related Articles | Metrics

Taking a 360 kt/a reforming hydrogenation unit of a refinery as an example, based on the principle of “minimizing revamping cost, maximizing equipment reuse and shortening the construction period”, the process route and effect of revamping an idle unit of naphtha hydrotreating (NHT) into a C₅/C₆ isomerization unit were discussed from the aspects of process selection, construction scheme, application effect and economic benefit evaluation. The results showed that the conversion of a 360 kt/a NHT unit to a C₅/C₆ isomerization unit was one of the best ways to reuse the idle NHT unit.

THEORETICAL CALCULATION AND EXPERIMENT STUDY ON CORROSION INHIBITION MECHANISM OF IMIDAZOLINE DERIVATIVES

2023, 54(4):  61-66. 

Asbtract ( 92 )   PDF  

References | Related Articles | Metrics

The structural characteristics of imidazoline derivatives were analyzed by quantum chemistry method. Three imidazoline derivatives, imidazoline, methyl imidazoline and nitrophenyl imidazoline, were designed. The molecular structure, charge distribution, orbital energy, binding energy of coordination with Fe atom and the structural characteristics of coordination compounds were calculated, the intermolecular force and binding energy between Fe atom and different imidazoline derivatives was analyzed, and three corresponding compounds were synthesized and their corrosion inhibition performance was evaluated. The results showed that the order of corrosion inhibition performance of imidazoline corrosion inhibitors from strong to weak was methyl imidazoline > imidazoline > nitrophenyl imidazoline. The stronger the electron-donating ability of the substituent in the imidazoline derivative molecule, the smaller the frontier molecular orbital energy difference between the imidazoline derivative molecule and the Fe atom, the better the effect of the coordination adsorption on the metal surface, and the better the corrosion inhibition performance of the corrosion inhibitor was.

 RELATIONSHIP BETWEEN STRUCTURE CHANGE AND STABILITY OF RESIDUE DURING EBULLATED BED HYDROCONVERSION

2023, 54(4):  67-72. 

Asbtract ( 115 )   PDF  

References | Related Articles | Metrics

The average molecular structural parameters and asphaltene aggregation state of typical Middle East residue and its hydrogenated oil at different conversion depths were determined by NMR (¹H-NMR) and optical microscopy, respectively, and the relationship between structure change and stability of residue during ebullated bed hydroconversion was investigated by combining group composition and instability parameters of the residue. The results showed that the average condensation degree of residue increased firstly and then decreased in the conversion range of 61.87% - 79.71%, which was related to the formation of sediment and its separation from the oil phase. After the residue was hydroconverted in ebullated bed, the aggregation degree of asphaltenes increased significantly, the cluster diameter of asphaltene increased with the increase of conversion rate, the maximum diameter could reach 58.97 μm. In the process of ebullated bed hydroconversion, the content of resins with the role to stabilize asphaltene in residue decreased obviously, while the content of saturated component, which was harmful to the stability of the asphaltenes, increased significantly.This would result in a continuous decrease in the stability of the residue.

TRIBOLOGICAL PROPERTIES OF A NITROGEN PHOSPHORUS TYPE EXTREME PRESSURE ANTIWEAR AGENT IN LITHIUM GREASE

2023, 54(4):  73-81. 

Asbtract ( 122 )   PDF  

References | Related Articles | Metrics

The tribological properties of a nitrogen phosphorus type extreme pressure anti-wear agent in lithium base grease were studied. Four ball test, SRV test and oscillating friction and wear test were carried out to compare the extreme pressure anti-wear and friction reduction properties of base grease and grease containing additives under extreme pressure. The results showed that P-N extreme pressure anti-wear additive with a mass fraction of 3.0% had outstanding anti-wear and antifriction properties and better extreme pressure properties. The anti-friction and anti-wear mechanism of extreme pressure was the formation of nitrogen and phosphorus-rich boundary lubrication film on the surface of the friction pair.

EFFECT OF BUTYL TRIPHENYL THIOPHOSPHATE ON ANTI-SHUDDER PERFORMANCE OF AUTOMATIC TRANSMISSION FLUID

2023, 54(4):  82-89. 

Asbtract ( 97 )   PDF  

Related Articles | Metrics

The effect of the content of butyl triphenyl thiophosphate (IR 232) on the anti-shudder performance of the automatic transmission fluid (ATF) was evaluated by the disc-on-disc tribo-test-rig (WAZAU). In view of the deficiency of the friction coefficient-velocity (μ-v) curve analysis method JASO M349 standard, the friction coefficient-friction endurance time (μ-t) curve analysis method was developed. The results showed that IR 232 had a great effect on the anti-shudder performance of ATF. Although the optimal range of IR 232 addition could be determined by using JASO standard μ-v curve analysis method, the exact time of anti-shudder performance failure could not be determined accurately. By using the method of μ-t, the precise time when ATF lost its anti-shudder performance could be accurately determined. Among the samples ATF A~F with different dosage of IR 232, ATF C showed the best anti-shudder performance and begun to lose anti-shudder performance at 65.7 h after the durability test, which indicated that the optimal dosage of IR 232 was 0.3%.

SYNTHESIS OF POLYACRYLATE EMULSION AS DEMULSIFIER FOR PRODUCED FLUID IN OFFSHORE OILFIELD

2023, 54(4):  90-97. 

Asbtract ( 100 )   PDF  

Related Articles | Metrics

Using ethyl methacrylate (EMA) as the main monomer, methacrylic acid (MAA) and acrylamide (AM) as the functional monomer, polyacrylate emulsion demulsifier was successfully synthesized by emulsion polymerization, the synthesis conditions were optimized, and the demulsification mechanism was analyzed. The results showed that the optimum synthesis conditions were as follows: EMA 5.91 g, MAA 3.34 g, AM 1.25 g, initiator (ammonium persulfate) 40 mg, emulsifier (sodium lauryl sulfate) 0.9 g, reaction temperature 73 ℃, agitation rate 200 r/min, and reaction time 4 h. When the demulsification temperature was 60 ℃, the settling time was 10 minutes, and the dosage of demulsifier was 30 mg/L, the oil removal rate of the produced fluid reached 90.9%. The properties of synthetic demulsifiers were better than those of commercial demulsifiers and emulsion demulsifiers used on offshore platforms. This is attributed to the abundant amphiphilic groups in its molecules, making it have excellent interfacial activity.

RESEARCH ON STRATEGY OF ENERGY EFFICIENCY CONSTRAINT BENCHMARKING IN OIL REFINING ENTERPRISES

2023, 54(4):  98-105. 

Asbtract ( 96 )   PDF  

References | Related Articles | Metrics

In order to meet the requirements of National Development and Reform Commission and the other departments of Chinese goverment on the benchmark value of energy efficiency constraint indicators in key areas, refinery A set energy efficiency improvement strategies by analyzing the energy consumption gap and combining with the enterprise development plan against the energy efficiency leader in the industry and the key energy consumption parameters of the refining enterprises in SINOPEC. The strategy was formulated at three levels,i.e. energy consumption planning, energy integration and unit strengthening of the whole plant. The theory of Energy Three-Link was applied, the gap was analyzed by benchmarking, and various energy efficiency improvement technologies were adopted. Several measures for improving energy efficiency were formulated from the aspects of strengthening energy-saving management, optimizing production operation, optimizing production process, improving production technology, improving efficiency of production equipment, and optimizing utilities, etc. It was expected to achieve the goal of energy efficiency constraint benchmark value, and help enterprises to achieve decarbonization goal.

EFFECT OF PROCCESS PARAMETERS ON THE FORMATION OF NITROGEN OXIDES IN INDUSTRIAL CATALYTIC CRACKING REGENERATION UNIT WITH FAST BED-TURBULENT BED

2023, 54(4):  106-113. 

Asbtract ( 139 )   PDF  

Related Articles | Metrics

The formation mechanism of nitrogen oxide (NO_x) in catalytic cracking device was preliminarily analyzed, the factors affacting NO_x content in regeneration flue gas were discussed in detail, and the industrial test of the fast-bed - turbulent bed regeneration process was carried out. The interaction of the temperature and component content of the regenerated flue gas was analyzed, and the rule of NO_x formation in the regeneration process was summarized. Effective control of NO_x content in the regeneration flue gas was achieved by changing the process conditions such as O₂ and CO content in the regenerator and the temperature of each section of the regenerator in series. The high-efficiency and low-cost control technology of NO_x content was formed to guide the operation of regeneration process. Under the background of energy saving and emission reduction, it was expected to provide an alternative technology for reducing the pollutant emission from FCC regeneration flue gas.

ADSORPTION-COUPLED PHOTOCATALYTIC DEGRADATION OF ALKANE VOCs BY TCN-TiO₂/Zn(CH₃COO)₂-ACF COMPOSITES

2023, 54(4):  114-124. 

Asbtract ( 98 )   PDF  

References | Related Articles | Metrics

The tubular carbon nitride (TCN) was prepared by hydrothermal lateral thermal stripping method, the ACF was successfully modified with Zn(CH₃COO)₂ by ultrasonic-vacuum impregnation method, TCN-TiO₂/Zn(CH₃COO)₂-ACF composites were prepared by loading TiO2 onto modified ACF. The composites were characterized by SEM, TEM, XRD, BET, XPS, FT-IR, UV-vis, PL, and I-T photocurrent response, and the degradation mechanism and degradation efficiency of n-hexane were studied. The results showed that the degradation effect of n-hexane was best when the mass fraction of TCN was 4% under light conditions, and the optimum preparation conditions were calcination at 450 ℃after loading twice. Under these conditions, the degradation rate of n-hexane gas with concentration of 200 mg/m³ at a space velocity of 1 000 h^-1 could reach 87.9%.When ACF was modified by Zn(CH₃COO)₂, the adsorption capacity of ACF was enhanced, the heterojunction of TCN and TiO₂ was formed, and the recombination rate of electron-hole was reduced.Thus, the adsorption-coupling photocatalytic efficiency of the composite photocatalyst could be improved.

RESEARCH ON FORMATION MECHANISM AND INFLUENCING FACTORS OF DEW POINT CORROSION IN ATMOSPHERIC DISTILLATION COLUMN OVERHEAD LINE

2023, 54(4):  125-132. 

Asbtract ( 125 )   PDF  

References | Related Articles | Metrics

In order to solve the dew point corrosion problem in the atmospheric distillation column overhead line in a petrochemical enterprise, the PR (Peng-Robinson) state equation method based on the binary interaction of hydrocarbon and water was adopted, and the process calculation model of the overhead system under standard conditions was established. Based on the mechanism of the dew point formation, the state changes of the corrosive medium in the oil-gas-water three-phase before and after the dew point were analyzed. The distribution of HCl and H₂S in the overhead line of the column under different water injection ratios and the influence of top pressure, stripping steam volume and water injection ratio on dew point temperature under different S and N contents in the feed oil and constant oil content were studied. The results showed that HCl and H₂S were the key factors causing dew point corrosion. With the condensation process, the content of HCl in the overhead line of the column increasesd, and the content of H2S increased first and then decreased. The dew point temperature of the overhead water is 100.45 °C, and there is a positive correlation between the column top pressure, stripping steam quantity, the water injection ratio and the dew point temperature, the average dew point temperature increases by 2.97 °C per 0.02 MPa of top pressure increases.

RESEARCH STATUS OF PROPERTIES AND COMPOSITION OF PYROLYSIS OIL FROM WASTE PLASTICS

2023, 54(4):  133-144. 

Asbtract ( 251 )   PDF  

References | Related Articles | Metrics

The pyrolysis of waste plastic is a kind of thermochemical treatment technology, which can not only avoid environmental pollution, but also alleviate the energy crisis. At the same time, high value-added products such as pyrolysis oil can be recovered, which has both economic benefits and environmental protection, and is the development trend of plastic recycling industry in the future. In this paper, the present status of analysis and research on pyrolysis oil of waste plastics at domestic and foreign was reviewed from the aspects of physical and chemical properties, element composition, distillation range distribution, hydrocarbon composition and non-hydrocarbon compounds. The effects of plastic type, reaction temperature, reaction time and catalyst on the properties and composition of waste plastic pyrolysis oil were introduced in detail. According to the characteristics and composition of waste plastics pyrolysis oil, the application direction of waste plastic pyrolysis oil was introduced，which provided data support for the optimization of the technology and high-value utilization of waste plastic pyrolysis oil in the future.