Aug.2015,Vol.44,No.4
CHEMICAL ENGINEERING OF OIL & GAS
ABSTRACTS
Process improvement research on enhancing propane recovery in Yingmai natural gas processing device
Huang Siyu1， Jiang Hong1， Ba Xili2， Liu Wu3， Zhu Cong4， Liu Yang5
（1.College of Oil and Natural Gas Engineering, Southwest Petroleum University, Chengdu 610500, China； 2. Chinese Petroleum Planning and Engineering Institute, Beijing 100083, China； 3. Chinese Petroleum Tarim Oilfield Company, Kuerle 841000, China； 4. College of Mechanical and Electrical Engineering, Southwest Petroleum University, Chengdu 610500， China； 5. Chinese Aviation Oil Tibet Limited Liability Company， Lhasa 850000, China）. CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp1-7,2015（ISSN 1007-3426, IN CHINESE）
Abstract: The cryogenic separation process by molecular sieve dehydration and J-T valve throttling refrigeration were used in Yingmai natural gas processing device to control the hydrocarbon and water dew point of the output natural gas and recover a small amount of light hydrocarbon. At present, the propane recovery of the device is only 22.64%. To improve the economic benefit of gas field development, the process improvement plan of the device aiming at propane recovery has being put forward after analyzing the existing problems. Compared with other propane recovery process, SCORE process has high propane recovery rate and low energy consumption, which is most suitable for the Yingmai natural gas processing device. After optimizing the deethanizer pressure, it was found that when the deethanizer pressure was 3 900 kPa, the device had higher income and the deethanizer had good operational stability. After the process improvement, the quality of the products met the requirements. The propane recovery rate of the device increased to 97.54% and the income of the device increased by 66.31%. Process improvement research of Yingmai natural gas processing device indicate that compared with other propane recovery process, SCORE process has more reasonable cold integration between de-hydrocarbon unit and deethanizer. SCORE process also has a high rate of propane recovery when deethanizer pressure is high，and it can decrease the compression power of the output gas for the propane recovery process which has high output pressure, as well as simplify the flow, save the energy and improve the efficiency.
Key words: Yingmai, high pressure condensate gas field, molecular sieve dehydration, natural gas process, propane recovery, SCORE process
Countermeasures of SO2 up-to-standard emission of the sulfur recovery unit in a refinery
Liu Yong1, Zhang Wanquan1, Li Feng1, Yuan Kan1, Yao Sunkun2(1. PertoChina Sichuan Petrochemical Company Ltd., Chengdu 611930, China; 2. Sichuan Tianyi Science and Technology Company, Chengdu 610225, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp8-13,2015（ISSN 1007-3426, IN CHINESE）
Abstract: A technical investigation, including process and system design, equipments and facilities, and operations etc., was carried out in a refinery to find the reasons of SO2 emission in the tail gas beyond the standard. The results showed that the direct reason was oil and light hydrocarbon carrying with rich amine solution. Further, investigation and analysis indicated that a series of reasons resulted in the oil and light hydrocarbon carrying with rich amine solution. The reasons included small size of gas-liquid separator, lower temperature of lean amine solution, higher temperature of recycle hydrocarbon gas in up-stream units, faulting design of oil skimming in amine flash drum of up-stream units, and insufficient design flow rate of the torch gas from rich amine flash drum. To solve the above problems, some corresponding solutions were put forward including the design of system and process flow design, process indexes, operation, and equipment modification.
Key words: emission, sulfur dioxide, investigation, analysis, sulfur recovery, refinery
Simulation of Claus sulfur recovery process based on HYSYS
Chen Xin1, Cao Dong2, Chen Long2, Cao Jie2（1. Research Institute of Natural Gas Technology, PetroChina Southwest Oil & Gasfield Company, Chengdu 610213, China; 2. Chongqing General Natural Gas Purification Plant, PetroChina Southwest Oil & Gasfield Company, Chongqing 401200, China）. CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp14-18,2015（ISSN 1007-3426, IN CHINESE）
Abstract: By self-defining the chemical reaction of the sulfur recovery process in the HYSYS software, taking different characteristics of the equipments into account, the simulation model of the sulfur recovery unit was established. The calculation results of the simulation model have a certain accuracy to be used as a reference for the engineering application.
Key words: HYSYS, Claus, sulfur recovery, simulate
Application of the fiber film desulfurization combination technology in removing sulfide and mercaptan from liquefied petroleum gas
Sun Shouhua(Sinochem Quanzhou Petrochemical Co., Ltd, Quanzhou 362103, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp19-23,2015（ISSN 1007-3426, IN CHINESE）
Abstract: The industrial application of the fiber film desulfurization combination technology in liquefied petroleum gas sweetening unit in a petrochemical company was introduced. The result indicated that the fiber film desulfurization combination technology had the advantages of great applicable activity and simple starting-up. The total sulfur content in liquefied petroleum gas in fluid catalytic cracking unit may reduce to 16.3-16.8 mg/m3 after sweetening; and the corrosion grade of copper sheet was 1a. The total sulfur concentration of liquefied petroleum gas in delayed coking unit may reduce to 50.8-77.8 mg/m3, and the corrosion grade of copper sheet was 1a, meeting the product quality requirement. After water washing, the sulfide concentrations in alkaline washing water of two sets of units were 17.91 mg/L and 73.83 mg/L, respectively, recovering the disulfides as by-products. The mass fraction of regenerated lye was above 15%, meeting the sweetening requirment of fiber film. The alkaline sludge could meet the discharge requirements after treated by wet oxidation.
Key words: fiber film, liquefied petroleum gas（LPG）, desulfurization, mercaptan removal, application
Application feasibility discussion of using oxygen-enriched process for an 80 kt/a sulfur recovery unit
Chu Erjun, Wang Jiyun（West Pacific Petrochemical Co., Ltd, Dalian 116600, China）. CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp24-27,2015（ISSN 1007-3426, IN CHINESE）
Abstract: This paper briefly described the main parameters of releasing oxygen-enriched air based on the air separation unit during the normal operation, as well as relevant design data of an 80×103 t/a sulfur recovery unit. Through analyzing and calculating main material balance, the feasibility of using released oxygen-enriched air from the air separation unit for the 80×103 t/a sulfur recovery unit was discussed.
Key words: sulfur recovery, oxygen-enriched, air separation unit, computational analysis, feasibility
Installation height calculation for outlet pipeline of horizontal thermosiphon reboiler of desulfurization and decarbonization device
Zhang Xiangguang1, Su Haiping1, Lin Liang1, Huang Yan2, Li Yanfang1（1. Xi’an Changqing Technology Engineering Co., Ltd, Xi’an 710018, China; 2. Oil Production Plant No.1 of PetroChina Changqing Oilfield Company，Yanan 716000, China）. CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp28-32,2015（ISSN 1007-3426, IN CHINESE）
Abstract: The shell side pressure balance calculation should be conducted in the installed designing process of the reboiler to determine the elevation difference and the installation dimensions between the tower and reboiler, and ensure the normal operation circulation of the reboiler. By analyzing the circulation system between the desulfurization and decarburization device regenerator and horizontal thermosyphon reboiler, it can be simplified as two parts of impetus and resistance calculation. Required installation height can be calculated using the principle of siphon pressure balance. In the process of calculation, the local resistance can be converted by the equivalent length of straight pipe resistance, and the calculate parameters can be read from simulation software such as Unisim. The pipe diameter of import and export may refer to SY/T 0011-2007 Code for Design of Natural Gas Conditioning Plant and are determined from the experience formulas provided by M.W.Kel-logg Company. Through the design calculation example and engineering example accounting, the reasonableness of the calculation method is verified, which has practical significance.
Key words: desulfurization, decarbonization, horizontal thermosiphon, reboiler, installation height
Operation summary of Sichuan Petrochemical 100×103 t/a sulfur recovery and tail gas treatment device
Wang Huiqiang(PetroChina Sichuan Petrochemical Company Limited, Chengdu 611930, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp33-38,2015（ISSN 1007-3426, IN CHINESE）
Abstract: This paper introduced the principle, process, characteristics, problems occurring during the startup stage and countermeasures of the 100×103 t/a sulfur recovery unit of PetroChina Sichuan Petrochemical Company. It also introduced the characteristics, loading and application of CT series catalyst. One year’s operating experiences indicated that the mass concentration of SO2 in exhaust gas is less than 400 mg/m3, which is far lower than 960 mg/m3 specified by the national standard GB 16297-1996 Integrated Emission Standard of Air Pollutants, and meet the requirements of the national standand GB 31570-2015 Emission Standard of Pollutants for Petroleum Refining Industry.
Key words: Sichuan Petrochemical，sulfur recovery, catalyst，meet the emission standard
Catalytic diesel oil processing route selection and economy analysis
Zhang Han, Wang Jiyun(West Pacific Petrochemical Co., Ltd. Dalian 116600, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp39-43,2015（ISSN 1007-3426, IN CHINESE）
Abstract: After the diesel quality upgrading to the national standard of grade III or superior to grade III, hydrogenation processing is necessary for FCC diesel of WEPEC. By analyzing the components of the diesel pool and selecting the available processing route of WEPEC, the results showed that the hydrogen consumption, energy consumption and processing costs of the process configuration were lower than those of the hydrocracking unit in 129 m3/t, 12.5×104 kJ/t and RMB 47.9 yuan/t units after the hydroprocessing of the diesel oil. Therefore, in the premise of avoiding over-temperature of the reactor bed, the most economic route of WEPEC is to blend FCC diesel oil as much as possible.
Key words: FCC diesel oil, diesel pool, blending, economy
Study on condensate recovery scheme improvement of oilfield associated gas
Qiao Zaipeng, Jiang Hong, Niu Rui, Chen Qian（College of Oil and Natural Gas Engineering, Southwest Petroleum University, Chengdu 610500, China）. CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp44-49,2015（ISSN 1007-3426, IN CHINESE）
Abstract: To treat oilfield associated gas with rich quantities and low pressure, direct heat exchange technology is used to recover propane and products. Problems of unreasonable utilization of system cold energy, poor adaptability of gas composition and high system energy consumption are generally existed. Taking an oil and gas processing unit as example, the improvement scheme is put forward to improve the overall economic benefits of the unit. Two-stage separation process is used. The propane recovery rate is increasing by adding reflux tank on the top of deethanizer, reducing the propane content in top feed of DHX tower, enhancing absorption effect of DHX tower; and the heat exchanger network of cold box is designed with the pinch point theory to improve the cold and heat integration of system and the utilization rate of cooling energy. After improving of cold box, the reboiler load of deethanizer reduces 189 kW, decreasing of 12.9%，the compressor load of propane refrigeration reduces 142.8 kW, and the utilization of cold energy is more reasonable. By improving scheme, the rate of propane recovery and the production of liquefied petroleum gas have increased greatly, the overall energy consumption of unit have changed little, and a considerable economic benefit would be achieved. Suggestions are recommended for application in similar working condition.
Key words: oilfield associated gas, scheme improvement, cold energy utilization, heat exchanger network, propane recovery
Study on strategies of calorific value adjustment in the LNG terminal
Hu Chao, Shi Tongqiang，Yang Guangyuan，Liu Qingsheng，Han Meng（Sinopec Qingdao LNG Co.,Ltd, Qingdao 266400, China）. CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp50-53,2015（ISSN 1007-3426, IN CHINESE）
Abstract: To achieve the exchange between LNG terminal transmission gas and natural gas pipeline network in Shandong Province, injection of liquid nitrogen is proposed to adjust the calorific value. Through comparative analysis, the nitrogen injection port is designed on the outlet pipeline of high-pressure pump, and compared with injection of nitrogen gas, injection of liquid nitrogen has lower cost and less power consumption. High calorific values and Wobbe index under three limiting conditions are calculated by PROII simulation to determine that the ratio range of liquid nitrogen injection is from 6.45 to 67.52 t LN2/100 t LNG on the outlet pipeline of high-pressure pump. Finally, the addition of major equipment and related parameters under the demand of the whole adjustment strategies are given based on the one million tons output amount of the LNG terminal. It can provide references and samples for the design of calorific value adjustment strategy in other LNG terminals.
Key words: LNG terminal, calorific value adjustment, nitrogen injection, Wobbe index
Selection of working fluid and parameters optimization for cryogenic power generation of LNG
Zhang Chao, Jin Haigang, Shao Guofen, Bu Xiaoling, Zhang Qilin, Fan Haiying
(Cooec-Enpal Engineering Co., Ltd, Qingdao 266101, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp54-58,2015（ISSN 1007-3426, IN CHINESE）
Abstract: Taken a company’s LNG (liquefied natural gas) cryogenic power generation project as an optimized object, the selection of working fluid and optimization of parameters were simulated by Aspen HYSYS. The simulation results demonstrated that the mixture of methane, ethane and propane as working fluid has more power generation than single substance, different proportions of the mixture generate different net power, and there is an optimal proportion. In the mixed substance, increasing the proportions of the propane or methane/ethane, electricity production presents a tendency of lower after the first increase. Furthermore, operation parameters have a great influence on the power generation. In comparison with inlet pressure of expander, the outlet pressure has more influence on power generation. While the outlet pressure of expander increases, the power generation first increases and then decreases. Meanwhile, the maximum net power generation for the same working fluid appears under the same outlet pressure condition with the different inlet pressures.
Key words: liquefied natural gas (LNG), cryogenic power generation, selection of working fluid, parameter optimization
Study on etherification performance of FCC light gasoline on the hierarchical porous Hβ zeolite
Qiu Yujia, Wang Yujia, Wang Haiyan(Chemical and Environment Department, Liaoning University of Petroleum Chemical, Fushun 113001, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp59-64,2015（ISSN 1007-3426, IN CHINESE）
Abstract: The hierarchical porous Hβ zeolite was prepared by the alkaline treatment of Hβ zeolite with NaOH solution, and the zeolite of before and after processing were characterized by XRD, SEM, N2 adsorption-desorption, NH3-TPD and Py-IR. The etherification reaction for FCC light gasoline on hierarchical porous Hβ zeolite was carried out in a fixed bed reactor. The effect of reaction temperature, space velocity, mole ratio of methanol and tert-olefin and pressure on the etherification reaction were studied. The results showed that alkali treatment could maintain Hβ zeolite crystal structure, and meanwhile increase the specific surface area and mesopore volume, and the amount of dium-strong acid and acid B, thus increase the etherification activity. In optimum conditions (temperature of 70 ℃, the space velocity of 1 h-1, MeOH/tert-olefins molar ratio of 1.1, the reaction pressure of 0.9 MPa), the tert-olefins conversion of 67.49% was received, which was higher than commercial Hβ zeolite by 11.7%.
Key words: Hβ zeolite, hierarchical porous, FCC light gasoline, etherification, alkali treatment
Technology research of the fracturing fluid for shale gas reservoir as “factory” fracturing: An example of the CNH3 well group “factory” fracturing
Liu Youquan1，Chen Pengfei1，Wu Wengang1，Zhang Qian1， Zhang Yadong1， Xiebing2，Long Shunmin1(1. Research Institute of Natural Gas Technology, PetroChina Southwest Oil & Gasfield Company，Chengdu 610213, China； 2.Chongqing University of Science and Technology, Chongqing 401331, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp65-68,2015（ISSN 1007-3426, IN CHINESE）
Abstract: “Factory” fracturing is the necessary requirement of benefit development in shale gas reservoir, according to the “factory” fracturing requirement, forming a slick water formulation which could meet the request of “factory” fracturing: low molecular weight, low viscosity emulsion friction reducing agent, friction reducing rate is 73%-78%, the dissolution time is less than 30 s, it could meet the high displacement, continuous mixing requirement; and using efficient bactericide, bactericidal rate of sulphate reducing bacteria is 100%, it could effectively reduce the damage to reservoir and production equipment; flowback fluid can be used repeatedly after simple treatment. CNH3 well group field test showed that the friction reduction rate is from 76.2% to 78.7% of slick water; the flowback rate is from 12.16% to 14.30%, the cumulative test production reached 20.95× 104 m3/d.
Key words: shale， factory， slick water， well group， volume fracturing
Applicability assessment of three different production casings in sour gas wells
Zeng Dezhi1，Zhang Naiyan1，Chen Rui2，Wang Feng3，Shi Taihe1， Ren Chengqiang1（1. State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation in Southwest Petroleum University, Chengdu 610500, China; 2. Sichuan Kehong Petroleum Engineering Co., Ltd., Chengdu 613213, China; 3. Research Institute of Natural Gas Technology, PetroChina Southwest Oil & Gasfield Company, Chengdu 610213, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp69-74,2015（ISSN 1007-3426, IN CHINESE）
Abstract: In order to assess the applicability and effect of temperature on corrosion behavior, the common specimens of three production casing steels（T95,110SS-2Cr and 825 steel） in different depths were subjected to acidic solution containing both 0.55 MPa H2S and 0.75 MPa CO2 at 55-100 ℃for 72 h in an autoclave, and micromorphologies and chemical compositions of corrosion products were obtained through scanning electron microscope (SEM) and energy dispersive X-ray (EDX), respectively. The weight-loss results show that the corrosion of 825 steel is slight according to the SY5329 standard, and the corrosion rate of 110SS-2Cr is lower than that of T95 steel, which explains its better anti-electrochemical corrosion performance. Besides, the corrosion rates of T95 steel and 110SS-2Cr steel increase as temperature rises. The microscopic analysis indicates that with temperature increasing, the corrosion products of T95 steel and 110SS-2Cr steel thicken and the tendency of crystallization and agglomeration is obvious, and the main chemical compositions are FexSy, FeCO3 and small amount of Cr. It is noted that the Cr content of 110SS-2Cr steel is higher than that of T95 steel, which accounts for the better protective effect and lower corrosion rate of 110SS-2Cr steel. Therefore, T95 steel is suggested to apply at the wellhead of production casing for its economy and practicality, the 825 steel can be used below the packer of production casing with its higher expense, 110SS-2Cr steel is appropriate to be used in the middle of production casing because of its poor SSCC resistance.
Key words: H2S/CO2, production casing, corrosion rate, polarization curves, corrosion products, applicability assessment
Study on the microrheological characteristics of partially hydrolyzed polyacrylamide
Kang Wanli1, Lu Yao1, Li Zhe1, Yang Hongbin1, He Yuwei2, Zuo Jin1, Liao Shuyu1(1. Research Institute of Enhanced Oil Recovery, China University of Petroleum(Beijing), Beijing 102249, China; 2. LDS Technology Limited, Beijing 100101, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp75-78,2015（ISSN 1007-3426, IN CHINESE）
Abstract: Based on the dynamic light scattering principle, the microrheological characteristics of partially hydrolyzed polyacrylamide influenced by concentration of NaCl, pH value, temperature and molecular weight were studied by Rheolaser. The mean square displacement (MSD) curve of HPAM was analyzed to obtain viscoelastic parameters such as macroscopical viscosity index (MVI) and elasticity index (EI). The results showed that with the decrease of temperature and concentration of NaCl and the increase of pH value and molecular weight, the value of MVI and EI of HPAM increased. The microcosmic mechanism of the results was explained and the superiority of microrheology on the research of polymer rheological characteristics was discussed.
Key words: microrheology, dynamic light scattering, partially hydrolyzed polyacrylamide, mean square displacement, viscoelastic parameters
Synthesis and properties evaluation of new aminated crude oil pour point depressant PSMA
Yu Shuai, Yu Ping, Wei Yunhe, Zhang Hongmin, Zhang Changqiao(School of Chemistry and Chemical Engineering, Shandong University, Jinan 250061, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp79-82,2015（ISSN 1007-3426, IN CHINESE）
Abstract: The copolymer poly(PSMA-a) composed of maleic anhydride and octadecyl methacrylate was synthesized with dispersion copolymerization method by using polyvinylpylrrolidone (PVP) as the dispersant and ethanol as the dispersion medium. Then the polymer was amidated by aminobenzene. The structure and thermal stability of the final polymer (PSMA) were characterized by Fourier transform infrared spectroscopy (FTIR) and thermal weight loss (TGA). In this thesis, the crude oil from Daqing Oilfield station was taken as the experimental subject, the property of pour point depression and viscosity reduction were measured by differential scanning calorimetry (DSC), oil solidifying point tester and viscosity tester. Then, the best ratio of monomer, reaction temperature, reaction time and dosage of initiator was determined through the orthogonal test. The results of the experiment indicated that the best pour point depression and viscosity reduction effect were achieved when the amount of the PPD taken in the experiment was 750 mg/L and the PVP dosage was 8% of total monomer mass.
Key words: pour point depressant, crude oil, dispersion polymerization, thermal analysis
Field pilot test of volume fracturing in tight sandstone well in Ansai Oilfield
Ji Wei1, Shen Kun1, Zhang Yuchao1, Niu Meng2, She Lijun1, Wang Haiqiang1，Chen Gang1(1. The First Production Plant, PetroChina Changqing Oilfield Company, Xi’an 716002, China; 2. Research Center of Exploration and Development,Yanchang Oilfield Co., Ltd, Xi’an 716001, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp83-86,2015（ISSN 1007-3426, IN CHINESE）
Abstract: Ansai Oilfield is a typical tight sandstone reservoir with “low pressure, low permeability, low production”, which has poor reservoir property and strong heterogeneity. The new well build the production only by fracturing. With the development of oilfield, the well affected by the closure pressure need second fracture or third fracture to restore production. However, by the limit of well selection conditions, conventional measures of increasing production only make low oil increasing, and the validity period is short since fracturing is hard to make new fracture. Taking Ansai Oilfield Xing 18-A as an example, this article specified the construction scheme and take mixed water volume fracturing pilot test with “large fluid measure, large displacement, large sand measure, low sand ratio” while taking the microseismic crack monitoring. Field application results showed that compared with conventional fracturing, the crack volume which was formed by this technology enlarged 126.7%, and the average single well daily oil-increasing improved 1.7 times. It showed obvious advantage in reservoir refracturing.
Key words: volume fracturing, tight sandstone reservoir, field test, microseismic crack monitoring, Ansai Oilfield
Experimental study of parameters optimization of rotational profile control operations in Bohai Oilfield: An example of A22 Well in LD5-2 Oilfield
Zhang Yunbao1, Xue Baoqing1, Lu Xiangguo2（1. Tianjin Branch Company，CNOOC, Tianjin 300452, China；2.Key Laboratory of Enhanced Oil Recovery of Ministry Education, Northeast Petroleum University, Daqing 163318, China）. CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp87-92,2015（ISSN 1007-3426, IN CHINESE）
Abstract: After years of development, formation heterogeneity has been strengthened gradually in LD5-2 Oilfield, which needs to adopt measure of reinforced fluid flow to enlarge sweep volume and improve water flooding development effect. In order to meet the needs of oilfield development technology, guided by the theory of reservoir engineering and physical chemistry, using techniques of instrument detection and physical simulation method, with LD5-2 reservoir geology and fluid properties as experiment platform, experimental study of rotational profile control operations was carried out. Results show that among the Cr3+ polymer gels prepared with three kinds of water, the viscosity of descaling water gel is bigger, the ability of fluid flow is stronger, and the oil displacement effect is better. When the polymer concentration increases, the viscosity of Cr3+ polymer gel also increases, and the ability of fluid flow strengthens, and the recovery factor increases. Under the condition of the same slug size of Cr3+ polymer gel, the way of multiple small gel slug and water alternating injection can reduce the dosage of oil displacement agent and get better oil displacement effect.
Key words: LD5-2 oil field, displacement rounds, Cr3+ polymer gel, polymer displacement effect, physical simulation, mechanism analysis
Synthesis of a hydrophobically associating polymer thickening agent and evaluation of the fracturing fluid properties
He Kunyi, Luo Mina, Zhong Yao, Qin Ziwei(College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu 610500, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp93-96,2015（ISSN 1007-3426, IN CHINESE）
Abstract: A hydrophobically associating polymer thickening agent HAPAM-18 for fracturing fluid was synthesized by the aqueous solution free-radical copolymerization of AM, AMPS and a cationic hydrophobic monomer MD-18. The thickening ability and interactions with surfactant of HMPAM-18 were studied as well as the fracturing fluid properties. Result shows that the apparent viscosity of HAMPAM-18 solution increased with increasing concentration and its critical aggregation concentration is 0.15 g/L. The interactions between HAPAM-18 and surfactants fitted the three stage model and the interactions between HAPAM-18 and SDBS is more intensive than that with CTAB. The fracturing fluid system composed of 0.6 g/L HAPAM-18 + 0.5 mmol/L SDBS + 2 g/L KCl reached a temperature resistance of 101 ℃ and showed good shear resistance and viscoelasticity. The fracturing fluid system can be completely broken with unmeasurable insoluble residuals by ammonium persulfate as the gel-breaker which means this system can be taken as clean fracturing fluid.
Key words: hydrophobic associating polymer, thickening agent, surfactant, clean fracturing fluid
A brief understanding on the ISO/TR 22302 Natural Gas-calculation of Methane Number
Tang Meng1,2, Cai Li1,2(1. Research Institute of Natural Gas Technology, PetroChina Southwest Oil&Gasfield Company,Chengdu 610213, China; 2. Key Laboratory of Natural Gas Quality and Energy Measurement, CNPC, Chengdu 610213, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp97-100,2015（ISSN 1007-3426, IN CHINESE）
Abstract: This article introduced the main contents of ISO/TR 22302:2014, including the definition of methane number, two calculation methods of methane number developed by Gas Research Institute (GRI), listed the limitation of two methods and calculated the methane numbers of 36 gas mixtures from European and 30 gas mixtures from China and Thailand. It discussed that if the difference between two GRI methods is more than 6, the composition of natural gas should not be in accordance with the limitation of the calculation method. ISO/TR 22302:2014 gives the technical supports for application of methane number.
Key words: natural gas， methane number， composition， calculation method
Effect of sampling system modification on the measurement results of LNG receiving terminal
Tang Xianming（Guangdong Dapeng LNG Limited Inc, Shenzhen 518048， China）. CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp101-105,2015（ISSN 1007-3426, IN CHINESE）
Abstract: LNG receiving terminal of Guangdong Dapeng Liquefied Natural Gas Limited Company was Built by EPC contract.After several years， operation, lab technicians found the original LNG sampling system had design fault, which could not take representative sample. For the LNG trade, the representative sample of LNG is the key to obtain accurate and reliable analysis results. In view of the shortcomings of the original sampling system, LNG liquid sample needs special vacuum insulation before it goes to vaporizer, and power supply for the vaporizer needs to be increased. By comparing with the old and new sampling system performance through LNG custody transfer, satisfactory results were obtained.
Key words: LNG, sampling system, modification, optimization, LNG custody transfer
Precaution and treatment of CO2-contaminated high density drilling fluid in Gao-Mo block
Yuan Zhiping1, Li Wei1, Xiao Zhenhua2(1. CCDC Drilling & Production Technology Research Institute, Guanghan 618300, China; 2. Exploration Division of PetroChina Southwest Oil & Gasfield Company, Chengdu 610051, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp106-109,2015（ISSN 1007-3426, IN CHINESE）
Abstract: Lab studies on CO2 contamination of high density drilling fluid was carried out. The influence of conventional drilling fluid chemicals on the CO2 contamination was evaluated. Meanwhile, CO2-contaminated high density drilling fluid was treated and the reasons for contamination were clarified. Eventually, a set of suitable precautions and solutions were proposed for CO2 contamination of high density drilling fluid in Sichuan Gao-Mo block.
Key words: drilling fluid, CO2 contamination, precaution, treatment
Aggregation-floatation technology for oily wastewater treatment at WHPD of BH Oilfield
Fang Jian(CNOOC Energy Technology & Services Limited-Safe and Enviromental Services Company, Tianjin 300458, China）. CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp110-113,2015（ISSN 1007-3426, IN CHINESE）
Abstract: In this study, aggregation and floatation technology has been used to improve the oil removal efficiency corresponding to the problems and characteristics of the production water from the WHPD of BH Oilfield. The results showed that the oil contents of treated water were under 20 mg/L through 2-stage treatment. Furthermore, the oil contents of the water collected at the outlet of the treatment process were below 10 mg/L through 3-stage treatment. A set of skid-mounted device for coalescence-gas floating oil removal was designed based on the space conditions of WHPD.
Key words: aggregation, floatation, production water, oil content
Risk evaluation of gas transmission station based on HAZOP and AEMA
Xing Jinduo1,2，Zhao Dongfeng1,2，Han Fenglei1,2, Chen Xiaowei1,2(1. Environment and Safety Technology Center of China University of Petroleum, Qingdao 266580, China; 2. Petroleum & Natural Gas Safety Production Engineering Technology Research Center of State Administration of Work Safety, Qingdao 266580, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp114-118,2015（ISSN 1007-3426, IN CHINESE）
Abstract: Aiming at comprehensively and objectively analyzing the safety of gas transmission stations, this paper proposed a novel method by combining HAZOP which is frequently used in chemical industry and AMEA which is mainly for human and management factors analysis. 4 first-grade assessment indicators and 17 second-grade assessment indicators were recognized after integrating all factors. The risk interaction matrix was subsequently established based on the characteristics of the gas transmission station. This matrix not only considered the impact of a single factor on the operation safety, but also analyzed the results from coupling actions by multiple factors. Finally, a case study with this method was conducted on the pressure-regulating unit of a gas transmission station, indicating that the unit was high risk. Quantitative information such as the risk value and the weight sorting of the risk factors were also concluded from the analysis. The studies showed that this risk assessment method has practical significance to safety management of gas station.
Key words: gas transmission station, HAZOP, AEMA, multi-factor, pressure-regulating unit, risk evaluation
Analysis of operational risk of urban gas based on fishbone diagram analysis
Zhao Yuhui1, Qiao Bei2, Xu Jun2, He Yi3(1. PetroChina Southwest Oil & Gasfield Company,Chengdu 610051,China; 2. Institute of Safety, Environmental and Technical Supervision of PetroChina Southwest Oil & Gasfield Company, Chengdu
610041,China; 3. Chongqing Gas Group， Chongqing 400700, China ). CHEMICAL ENGINEERING OF OIL & GAS, VOL.44, NO.4,pp119-124,2015（ISSN 1007-3426, IN CHINESE）
Abstract: Based on data of accident case of the urban gas operations, safety inspection result and accident statistical analysis, a variety of possible risk factors are identified in the process of city gas operation. And using the risk analysis method based on a fishbone diagram, 11 important risk factors of city gas safety operation are obtained, such as low pipe and construction quality, the third party damage, loss of pipe network data, loss of geographic information of underground pipe network, not preventive upgrading, lack of safety knowledge for users and also lack of safety awareness to employees, no odorization, planning backward, and lack of enforcement, etc. Some advices are put forward to prevent risks.
Key words: city gas, operational risk, fishbone diagram analysis, risk identification, operational safety, brain storming, pipe and construction quality, third party damage
