CHEMICAL ENGINEERING OF OIL & GAS
Research of crude oil desulfurization technology in well sites
Zhang Daqiu1, Jing Jiyun2, Yang Lin2, Wang Tangyu3（1.Changchun Occupation Hazard Detection and Inspection Center,Changchun 130000,Jilin,China; 2. Southwest Petroleum University, Chengdu 610500, Sichuan, China; 3.China Petroleum Engineering Design Co., Ltd of Southwest Company, Chengdu 610017, Sichuan, China）. CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp1～5,2014（ISSN 1007-3426, IN CHINESE）
Abstract: The existence of hydrogen sulfide in crude oil will cause the corrosion of the equipment，lower oil quality and a serious threat to personal safety. Therefore, it is important to remove hydrogen sulfide in the process of crude oil production. To solve the problem of highsulfur crude oil produced in A well area in the western China, the gas stripping method and the chemical method have both been analyzed. Based on the stimulation of stripping process, the optimized parameters of gas stripping are obtained, namely tower pressure is 0.3 MPa, plate number is 6, stripping gas is 4.7-6.1 m3/t, and reboiler temperature is 152.0-41.6 ℃ , the amount of stripping gas and the reboiler temperature are adjusted according to the adequacy of gas and the energy consumption. The desulfurizer mainly composed of two isopropyl complexes has been screened out and the effect of dosage, operating time, water content, temperature on the desulfurization have also been evaluated.
Key words: crude oil, hydrogen sulfide, H2S, gas stripping, desulfurizer
Analysis on elemental sulfur generated from the molecular sieve dehydration unit and modification scheme
Fang Zheng1, Wang Guozhi1, Zhang Lei2, Li Linhui2, Li Ming2 (1. CNPC (International) Aktobe(Kazakhstan) Oil & Gas Co.,Ltd，Beijing 100101，China; 2. China Petroleum Engineering Co.,Ltd of Southwest Company, Chengdu 610041, Sichuan，China）. CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp6～11,2014（ISSN 1007-3426, IN CHINESE）
Abstract: According to the analysis data of the solid block in the molecular sieve dehydration unit of wet gas reinjection engineering at Zananor oil field, Republic of Kazakhstan, the solid block is determined as elemental sulfur and its mixture. The cause of sulfur in the unit and the effects of equipment, pipe, valve in the unit etc. are analyzed and the amending plan is provided. It gives reference for the design of similar molecular sieve dehydration unit for natural gas containing oxygen and hydrogen sulfide.
Key words: molecular sieve， dehydration unit， oxygen， sour natural gas， elemental sulfur
Research on grading process of hydrocracking catalysts
Han Longnian1, Fang Xiangchen2, Peng Chong2, Zeng Ronghui2, Zhao Tao1 (1. Liaoning University of Petroleum & Chemical Technology, Fushun 113001, Liaoning, China；2. Fushun Research Institute of Petroleum and Petrochemicals, Fushun 113001, Liaoning, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp12～16,2014（ISSN 1007-3426, IN CHINESE）
Abstract: This paper introduced hydrocracking catalysts grading technology developed by Fushun Research Institute of Petroleum and Petrochemicals (FRIPP). Test results of hydrocracking catalysts grading (C/A-B) showed that using grading loading technology could not only provide qualified clean fuel, but also reduce the cooled hydrogen consumption of refinery, and it could produce heavy naphtha with high aromatic potential, jet fuel with high smoking point, diesel with low solidifying point and hydrocracking residue with low BMCI value, which could meet demands of petrochemical feedstock and fuel for refinery at different stages. Moreover, this technology could relatively raise the outlet temperature of hydrocracker along with increase of heat source temperature of heatexchanger.
Key words: vacuum gas oil (VGO), hydrocracking, catalysts grading, energy saving and consumption reducing
Improvement and operation optimization of Gaoshangpu natural gas processing device
Huang Siyu1, Wu Yinqiang2, Zhu Cong1, Sun Lipeng3(1.Southwest Petroleum University, Chengdu 610500, Sichuan, China；2.Oil and Gas Gatheringand Transportation Company of Jidong Oilfield Company, Tangshan 063200, Hebei, China；3. PetroChina Chengdu Lubricant Blending Plant, Chengdu 610083, Sichuan, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp17～23,2014（ISSN 1007-3426, IN CHINESE）
Abstract: The DHX condensation and separation process by propane and expansion refrigeration are used to recovery C3+ in Gaoshangpu natural gas processing device. Due to the decreasing of feed gas flow rate, the increasing of CO2 and H2S content in feed gas, and the variations of processing device operating parameters, a series of problems occurred including copper corrosion test unqualified in LPG, equipment freezing and low propane recovery rate. Based on the analysis of existing problems, processing technology was improved and the CO2 and H2S of feed gas were removed to reasonable range to solve the problem of equipment corrosion, freezing and reduce the limit of acid component to the condensing temperature. The main adjustable parameters which can influence propane recovery rate and energy consumption of the device were screened out, including the expander outlet pressure, deethanizer operating pressure, deethanizer bottom temperature, and debutanizer operating pressure. By using HYSYS simulation to analyze the influence of the main adjustable parameters on propane recovery rate and energy consumption and to optimize the operating parameters, the balance between propane recovery and energy consumption was realized and maximum benefit was achieved. After optimization, although the energy cost increase 1.081 million yuan every year, but the product income increase 4.398 million yuan, the annual economic benefit increase 3.317 million yuan.
Key words: NGL recovery, DHX process, copper corrosion test in LPG, equipment freezing, propane recovery rate, operation optimization
Running experience and problems of natural gas purification unit in Qijiang branch of Chongqing Natural Gas Purification Plant General
Qiu Bin，Yan Ping，Li Tingting，Wang Xiaoqiang(Qijiang Branch of Chongqing Natural Gas Purification Plant General, PetroChina Southwest Oil & Gasfield Company，Chongqing 401433，China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp24～28,2014（ISSN 1007-3426, IN CHINESE）
Abstract: Relying on the nearly six years operational experience of Qijiang branch of Chongqing Natural Gas Purification Plant General, the advantages and disadvantages of process design of the purification device were analyzed, the necessity of process and equipment transformation was discussed, and the specific transformation program was proposed. The operation results have verified the validity of modification scheme.
Key words: natural gas purification, desulfurization, dehydration, sulfur recovery
Technical measures to improve running cycle of delayed coking unit
Li Lin, Chen Xiaolong（Refinery of PetroChina Lanzhou Petrochemical Company, Lanzhou 730060, Gansu, China）. CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp29～32,2014（ISSN 1007-3426, IN CHINESE）
Abstract: The main factors influencing running cycle of delayed coking unit were analyzed, and the technical measures to improve running cycle in recently years were introduced, including no blended heavy oil from ethylene cracking and reducing the blended proportion of deoiled asphalt to optimize composition of feedstock; controlling fractionator bottom temperature and steam quantity of purge of coke drum, and prolonging injection of defoamer and quench oil after switching tower to optimize operation condition; changing injecting position of anticoking agent to decrease coke deposit at the bottom of fractionator and furnace tubes from furnace inlet to fractionator bottom; modifying injection mode of quench oil at coke tower top to decrease coke deposit at fractionator bottom and oilgas lines from directly injection through three points to injection through a ring distributor. With the adoption of these measures, the flow of circulating oil pump at fractionator bottom increased from 5 t/h to 20 t/h, pressure drop of furnace tubes reduced from 0.21-0.25 MPa to 0.11-0.13 MPa, pressure drop of coke tower top reduced from 0.008-0.011 MPa to 0.005-0.009 MPa, the coking of fractionator bottom, furnace tubes and large oil and gas line were alleviated, the running cycle of delayed coking unit was prolonged from 10 months to 15 months and above, and the long period operation of unit was realized.
Key words: delayed coking, optimization, coking, technical measures, running cycle
Experimental study on replacement of methane hydrates by CO2
Xing Yanqing, Qi Yingxia, Yu Zhiguang, Wang Le(Faculty of Energy and Power Engineer, University of Shanghai for Science and Technology, Shanghai 200093, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp33～38,2014（ISSN 1007-3426, IN CHINESE）
Abstract: Replacement of methane hydrate by CO2 is a new approach for the development of CH4, and the method can develop CH4 and store CO2 permanently. By optimizing design of experiment device, the influences on displacement efficiency of temperature and pressure in the system of quartz sand media are studied. The experiment results show that the replacement rates are 1.75%, 6.99%, 13.43%, 5.53%, 22.64%, 44.90% respectively, the corresponding replacement temperature are 273.15 K, 274.15 K, 275.15 K, 276.15 K, 277.15 K, 278.15 K, and the CO2 charge pressure is constant at 2.5 MPa. On the other hand, the replacement efficiency are 37.11%, 13.43%, 3.44%, 4.58% respectively, corresponding to the CO2 charge pressure at 2.0 MPa, 2.5 MPa, 3.0 MPa, 3.5 MPa and the replacement temperature being constant at 275.15 K. Therefore, temperature and pressure are driving force factors of CO2 replacement of CH4 hydrate reaction.
Key words: methane, hydrate, replacement ratio, carbon dioxide
Application analysis of LNG liquefaction technology in outlying dispersed well
Ji Weian,Wen Dongyun（Research Institute of Natural Gas Technology, PetroChina Southwest Oil & Gasfield Company, Chengdu 610213, Sichuan, China）. CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp39～43,2014（ISSN 1007-3426, IN CHINESE）
Abstract: Adaptability of natural gas pretreatment process including desulfurization, dehydration, decarburization, demercuration and condensate recovery in outlying dispersed well are analyzed. In order to be used in outlying dispersed well, working characteristics of three natural gas liquefaction processes including cascade refrigeration cycle, mixed refrigerant refrigeration cycle and expander refrigeration cycle have also been compared. The process of cascade refrigeration cycle is too complex to be suitable for outlying dispersed well. MRC refrigeration has high flexibility, low energy consumption and strong adaptability, therefore it can be used to most of outlying dispersed wells. Expander refrigeration is characterized by simple operation, small occupied area and easy to be skid-mounted, so it is suitable for stable operation conditions and higher well head pressure. So far as current technology level, the single wells containing no sulfur, low carbon dioxide and low heavy hydrocarbon content are more suitable for outlying dispersed well.
Key words: LNG, liquefaction, outlying dispersed well, desulfurization, dehydration, decarburization, demercuration, condensate recovery
Usability research of the low proportional methanol gasoline for motor
Zhang Xinzhuang, Zhang Shuqin, Zhang Juanli(Research Institute of Shaanxi Yanchang Petroleum (Group) Co., Ltd, Xi'an 710075, Shaanxi, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp44～48,2014（ISSN 1007-3426, IN CHINESE）
Abstract: Combustion performance of the low proportional methanol gasoline used in 4G15S gasoline engine and Hyundai ix35 car was studied. Taking M15 and M25 methanol gasoline as test samples, burning characterized data about the dynamic performance, economy, stability and discharge were tested and compared with 93# gasoline. The results showed that the engine power increased, the acceleration time and acceleration distance decreased after burning M15 and M25 methanol gasoline; both effective fuel consumption rate and average fuel consumption increased; the stability is as the same as 93# gasoline; and CO and HC emissions of the tail gas decreased obviously. Research conclusions confirmed M15 and M25 methanol gasoline had good service performance, which could provide some reference basis for the practical application of the low proportion methanol gasoline.
Key words: methanol gasoline, dynamic performance, fuel consumption, emission characteristics
Research on natural gas heat value adjustment technology
Gao Xiumin, Yu Zhi, Zeng Shubing, Wang Yanrui, Song Wenlu（China Offshore Oil Engineering Corporation, Tianjin 300452, China）. CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp49～52,2014（ISSN 1007-3426, IN CHINESE）
Abstract: With the interconnection of natural gas networks in China, there is an important practical significance to research natural gas interchangeability with different combustion characteristics. Based on the gas source diversification of some power plant in Hong Kong, this paper studies the technology of natural gas heat value adjustment. It is proved that the method of adding LPG to increase the heat value, and adding nitrogen (or liquid nitrogen), air or other low calorific gas to reduce the heat value is feasible.
Key words: natural gas, LNG, heat value adjustment, Wobbe index, modified Wobbe index, interchangeability
Discussion on liquid recycling technology in mass production operation
Xiong Ying1, Liu Youquan1, Chen Pengfei1, Li Fanshu1, Wu Wengang1，Zhao Wanwei1, Zhao Hao2(1. Research Institute of Natural Gas Technology, PetroChina Southwest Oil & Gasfield Company, Chengdu 610213,Sichuan, China; 2. Southern Sichuan Gas District, PetroChina Southwest Oil & Gasfield Company, Luzhou 629000, Sichuan, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp53～57,2014（ISSN 1007-3426, IN CHINESE）
Abstract: For lack of water source, processing difficulties of fracturing flowback fluid and environmental pollution risk in volume fracturing process of shale gas, tight gas and other unconventional gas reservoir, the fluid recycling technique in the mass increase production was discussed. Mass increase production requires a lot of water, so the contradiction between supply and demand of water near the well site is very outstanding. At the same time, to produce a large amount of fracturing flowback fluid, it faces the grim situation of environment.and restricts the development of unconventional gas reservoir. The composition of fracturing flowback fluid is complex, mainly depends on water quality of fracturing fluid, fracturing liquid composition, reservoir geologic chemistry, and formation water, etc. These substances will influence the reuse performance of fracturing flowback fluid, so they need to be dealt with. The fluid recycle technique in the mass increase production can satisfy the performance of fracturing flowback fluid construction requirements once again mainly through the disinfection, settlement in addition to the mechanical impurities, chemical precipitation in addition to the high metal ions, compensatory loss additives etc. The technology was widely used in tight gas reservoirs of Xujiahe and tight oil reservoirs of Jurassic in Sichuan basin. The utilization ratio of flowback fluid after recycling is 95%, saving water source and achieving the circular economy.
Key words: reutilization, fracturing flowback fluid, slick water, gelled fracturing fluid, pollution of the environment, water resource
Performance test of a new super 13Cr oil drill pipe used for tight gas reservoir drilling and complication
Zeng Dezhi1, Tian Gang1, Shi Taihe1, Hou Duo1, Jia Huaming2, Lu Qiang2, Zhao Peng3(1. State Key Laboratory of Oil & Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, Sichuan,China; 2. Engineering Department of PetroChina Tarim Oilfield Company, Korla 841000, Xinjiang,China; 3. Baoshan Iron & Steel Co., Ltd, Shanghai 201900, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp58～61,2014（ISSN 1007-3426, IN CHINESE）
Abstract: A new high strength super 13Cr oil drill pipe was developed for tight gas reservoir exploitation in Tarim oilfield. This paper studies the tensile property and impact property of S135 dirll pipe and new super 13Cr oil drill pipe by a material tensile testing machine and a instrumented impact testing machine respectively. Their corrosion resistance to CO2 is also studied through high temperature and high pressure autoclave test. The results show that the ultimate strength of the new super 13Cr steel reaches 976 MPa, with the yielding strength 937 MPa and elongation 19.0%. Its impact energy reaches 162.82 J. Compared with S135 steel, the new super 13Cr steel has similar strength property and better impact property. Under the test condition, the corrosion rate of the super 13Cr steel is 0.003 6 mm/a in gas phase and 0.039 4 mm/a in liquid phase. Therefore, the new super 13Cr oil drill pipe can meet the requirement of drilling and well complication. The new oil drill pipe could provide support for tight gas reservoir nitrogen drilling and well complication.
Key words: tight gas reservoir, new super 13Cr oil drill pipe, S135 drill pipe, mechanical property, corrosion rate
Solution characterization and displacement efficiency research of ultra high molecular weight association polymer
Xu Hui(Geoscience Research Institute of Shengli Oilfield Company，Sinopec,
Dongying 257015, Shandong,China) . CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp62～66,2014（ISSN 1007-3426, IN CHINESE）
Abstract: Ultra high molecular weight association polymer is a new kind of oil displacement polymer. Compared with common HPAM, it is qualified with high molecular weight and some degree of association action. It is different from the common oil displacement polymer with its morphology of the aggregate and displacement efficiency. A kind of ultra high molecular weight association polymer was chosen. Through Anton Paar rheometer test, CRYO-SEM test and flooding physical simulation process test, the viscosifying ability, viscoelastic behavior, morphology of the aggregate, profile control and displacement efficiency were evaluated. The results showed that compared with common HPAM, the ultra high molecular weight association polymer was qualified with better viscosifying ability, better viscoelastic behavior under salty water condition. It also showed a good oil displacement effect at high temperature and high salinity reservoir in Shengli oilfield, and it has a good application prospect.
Key words: viscosifying ability, viscoelastic modulus, morphology of the aggregate, CRYOSEM, displacement efficiency
Stability performance of MTA agglomerated cake forming agent at low temperature
He Jibiao, Lai Pengfei, Wen Guiping, Huang Ju，Wang Qinggui, Zhang Wenping, Sun Dexing, Gu Jun(Faculty of Earth Resources, China University of Geosciences, Wuhan 430074, Hubei, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp67～72,2014（ISSN 1007-3426, IN CHINESE）
Abstract: The crystallization phenomenon of the MTA (mud cake to agglomerated cake) agglomerated cake forming agent at low temperature brings a new challenge to the popularization and application of MTA method. It is of great theoretical significance and use value to fully understand its stability performance at low temperature. The result of single factor comparative experiment showed that temperature decreasing was the main reason for the phenomenon of solute crystallization. The changes of anion concentration (such as Cl-，NO3-，SO42-) before and after crystallization were analyzed by ion chromatography(IC), and the precipitated crystal was determined as sodium sulfate decahydrate. The research result showed that commonion effect and hydrogen bonding coexist in GA-ⅠA solution. Commonion effect was unfavorable to the stability of sodium sulfate solution, while hydrogen bonding was opposite. In certain condition, interaction between them was in dynamic equilibrium, which influenced simultaneously and mutually the stability performance of the MTA agglomerated cake forming agent at low temperature.
Key words: cementformation interface，the agglomerated cake forming agent，solute crystallization，commonion effect，hydrogen bonding
New progress of injection technology for water injection well in Shengli oilfield
Li Changyou(Oil Production Technology Research Institute of Shengli Oilfield Company, Dongying 257000, Shandong, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp73～77,2014（ISSN 1007-3426, IN CHINESE）
Abstract: Shengli oilfield was mainly developed by water flooding. There were 1 954 layers that had not adequate water injection, which was short of 8.6×104 m3 per day. There were 576 layers in low permeability oilfield among them, which was short of 1.2×104 m3 per day. The main plugging removal and increase injection techniques at home and abroad are described in this paper. Particularly, the development of these techniques in Shengli oilfield was summarized, and the fitting injection measures were collected according to different short shot reasons in Shengli oilfield. The acidification with hydrochloric acid and mud acid in midhigh permeability reservoir and plug removal, matrix processing and activity of decreasing pressure and augmented injection technology in low permeability oilfield are implemented. In the aspect of physical stimulation, the technologies such as hydraulic deep penetration perforation, horizontal well drilling technology and the radial vibration of plugging removal technology, and added the matching technology of preprocessing and post discharge were mainly implemented. With the application of new technology, the surface modification of increasing injection technology, and pulse plugging removal test application technology conditions were analyzed. Finally, the research direction for the next step was put forward, aiming at the problems in short injection.
Key words: Shengli oilfield, injection well stimulation, acid defuse plugging, surface modification, high energy electrical pulses
Technological progress and developing direction of fracturing technology in Ansai oilfield
Huang Zhanwei, Zhang Yuchao, Qiu Jiayou, Guo Liang, Ji We, Zhong Zhiyong, Shi Xiaoliang, Wang Yan(Oil Production Plant No.1, PetroChina Changqing Oilfield Company, Yan’an 716000, Shaanxi, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp78～81,2014（ISSN 1007-3426, IN CHINESE）
Abstract: Ansai oilfield is a typical lowpermeability, low pressure, and low productivity reservoir. The new oil well only can be built by fracturing , and most of other wells still need multiple fracturing to improve its productivity.Therefore, the fracturing technology has being actively explored and improved since the 1980s in Ansai oilfield; and has been basically formed two technical systems as “water control” and “volume fracturing”. This paper reviews the development of fracturing, analyses the existing technology adapted in Ansai oilfield, and points out developing direction of fracturing technology in order to provide the reference for the similar reservoir.
Key words: Ansai oilfield, fracturing technology, technological progress, developing direction
Current situation and development trend of automobile diesel standards in China
Si Yunhang1, Zhu Yuqin1, Zou Rongmei2, Guo Fan1, Wang Jiachun3(1. Xi 'an Shiyou University, Xi 'an 710065, Shaanxi, China; 2. China Petroleum Engineering Co., Ltd, Southwest Company, Chengdu 610041, Sichuan, China; 3. Xinjiang Dushanzi Tianli High＆New Tech Co., Ltd, Dushanzi 833600, Xinjiang,China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp82～86,2014（ISSN 1007-3426, IN CHINESE）
Abstract: This paper describes the evolution course of automotive diesel standards in China, and briefly analyzes the current situation, then summarizes the development trend of their seven important technical indexes, finally analyzes the reasons of their continuous improvement. Automotive diesel standards have been developing straight forward the direction of clean oil. Compared with EU, USA and Japan, automotive diesel standards relatively lag behind others in China, so it is imperative to improve the quality of the product. The heavy and inferior properties of the crude oil process, the low production capacity of installations, and the lack of competitive catalysts have limited the upgrading of diesel quality in China. Based on the above reasons, a new automotive diesel standard will be prospected, namely formulating automotive diesel standard in line with China's national conditions, giving appropriate financial subsidies to refineries, supervising the implementation of automotive diesel fuel in China, developing and popularizing the core technology of diesel production.
Key words: automotive diesel fuels, technical index, current situation, prospect
Construction of quantitytransfer system of LNG dispensers in China
Zhao Pujun, Xiong Maotao, Yang Xiujie, Lei Li, Luo Yanfei, Yang Zhao(National Institute of Measurement and Testing Technology, Chengdu 610021, Sichuan, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp87～90,2014（ISSN 1007-3426, IN CHINESE）
Abstract: With the rapid increase of the LNG gas stations and the LNG vehicles, the LNG dispensers are increasingly available. The working principle of LNG dispensers as the starting point, the national verification regulation and the program for pattern evaluation of LNG dispensers are introduced. The traceability and transfer of quantity of LNG are analyzed. The developing tendency of LNG dispensers in China is prospected. The research results of the paper will promote the development and study of LNG dispensers industry.
Key words: LNG dispensers, quantitytransfer system, national verification regulation, traceability and transfer of quantity
Application of verification techniques in natural gas flow measurement using differential pressure flow meter
Li Wanjun1,2，Lai Zhongze1，Duan Jiqin1,2，Wang Zhi3(1. Research Institute of Natural Gas technology, PetroChina Southwest Oil and Gasfield Company, Chengdu 610213,Sichuan, China; 2. Chengdu Branch of China Natural Petroleum & Natural Gas Mass Flowrate Calibration Staion, Chengdu 610213, Sichuan, China;3. Quality, Safety and Environmental Protection Department, PetroChina Southwest Oil & Gasfield Company, Chengdu 610213, Sichuan, China) . CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp91～93,2014（ISSN 1007-3426, IN CHINESE）
Abstract: As a continuous and unrepeated measurement, natural gas flow measurement maybe cause high cost from incorrect measurement. Hence, it is necessary to be strict in the process control of gas flow measurement. To ensure measurement accurate and reliable, the verification technique is one of the effective methods to implement process control, and it not only be applied in laboratory, but also be widely applied in industrial metrology. The paper analyzes the applications of the verification method at home and abroad，proposes the development project of verification system used in natural gas flow measurement, which is put into practice and achieve remarkable results.
Key words: natural gas, flow, measurement, verification, application
Numerical simulation of urban buried gas pipeline leakage and diffusion
Cheng Mengmeng1，Wu Ming1，Zhao Ling1，Liu Ke2，Shao Dawei2，Yang Mingyue1(1.College of Petroleum Engineering，Liaoning Shihua University，Fushun 113001，Liaoning,China；2. Shenyang Institute of Special Equipment Inspection & Research，Shenyang 110000, Liaoning，China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp94～98,2014（ISSN 1007-3426, IN CHINESE）
Abstract: To study the diffusing of gas piercing leakage in urban buried gas pipeline, combining the finite volume method, CFD simulation models are established by Gambit 2.4 at different leakage locations. The diffusion rule of gas in soil and air are simulated by Fluent 6.3 under the three leakage conditions of the upper, lower and leeward side of the gas pipeline. The research result shows that the lower leakage in soil and air is the largest diffusion hazard area. If the valves at both ends of the pipeline are shut off, the gas diffusion hazard area will gradually get smaller. The studies can also provide the theoretical foundation for the personnel evacuation and security maintenance of pipelines in the scene of natural gas release.
Key words: gas pipeline, leakage, diffusion, numerical simulation
Study of HAZOP revalidation approach
Xu Jing1, Zhao Dongfeng2, Zhao Zhiqiang3(1．College of Electromechanical Engineering, China University of Petroleum (East China), Qingdao 266580,Shandong, China; 2. College of Chemistry & Chemical Engineering, China University of Petroleum(East China）, Qingdao 266580, Shandong,China; 3. Qingdao asis Environment ＆ Safety Technology Co.,Ltd，Qingdao 266555，Shandong, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp99～103,2014（ISSN 1007-3426, IN CHINESE）
Abstract: HAZOP evaluation method is used to analyze the risk of process by the worldwide chemical enterprises and design units. However, Standard Specification for many countries stipulate that the enterprise needs to carry on the process hazard analysis once again (revalidating) in several years later. The goal of periodic revalidation is to identify the cumulative changes of risk over time and to improve understanding of risk. The ultimate goal is to avoid accidents，but there is no systematic approach to guide the HAZOP revalidation at present. If we redo HAZOP blindly (performing a new HAZOP similar to the initial one)， it will only be timeconsuming. This paper introduces the concept of HAZOP revalidation which is based on the analysis of initial HAZOP and discusses many factors that need to be considered for the revalidation such as the change management, accident analysis and HAZOP report quality. At the same time，the specific procedure and approach of the HAZOP revalidation are proposed. The panel of experts scoring method is used to determine the revalidating approach and then decide whether to redo or update the initial HAZOP. If the scoring results suggest to redo the HAZOP, then the Hazard and Operability Analysis were conducted in accordance with the complete HAZOP procedures; if the scoring results suggest to update the initial HAZOP，then previous HAZOP analysis results were modified and supplemented to meet enterprise current status. This approach is not only timesaving, but also more targeted which can guide enterprises to conduct better and faster HAZOP revalidation.
Key words: HAZOP, revalidation, update, process hazard analysis, change of management
Primary investigation of CBMdusts purification in Jincheng of Shanxi
Chen Hongming1, Guo Jian1, Qin Feihu2, Du Xiaodong1, Qin Lifeng1, Xia Wanyong3(1. PetroChina Huabei Oilfield CBM Branch Company，Jincheng 048000, Shanxi, China; 2. CNPC Jichai Power Equipment Company Chengdu Compressor Plant, Chengdu 610100，Sichuan, China; 3. Sichuan Jiangyou Kelyu Purification Instruments Limited Company, Mianyang 621701，Sichuan, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp104～107,2014（ISSN 1007-3426, IN CHINESE）
Abstract: This paper investigated and compared the grossefficiency of purification, efficiency of sizing particles purification, stability of operation, safety of exploitation and economy of three types of filtration cores in the practical condition. Through test data evaluation, the result showed that the special designed nickelbased metal filtration core with the effects of penetration & interception is more competent than that of fiber filtration core with the effects of coalesce in the CBM purification featured with high flow velocity, variable concentration of dusts and watercontaining, and it has technology and economy advantages.
Key words: coalbed methane exploitation, gathering and transportation process, dusts purification, coal particles prevention, filtration separation
Experimental study on reinjection treatment of unconventional fracturing flowback fluid
Han Zhuo1, Guo Wei2, Zhang Tailiang2, Wang Yang1, Zou Jinglun1, Li Zefeng2
(1. Technology Inspection Center of Sinopec Shengli Oilfield Company, Dongying 257000, Shandong, China; 2. College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu 610500, Sichuan, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.1,pp108～112,2014（ISSN 1007-3426, IN CHINESE）
Abstract: Flowback waste water from fracturing operation in the production process of oil and gas wells has become one of main pollution sources in the oilfield. This paper analyzed the main pollution components of the unconventional drilling fracturing flowback fluid, put forward the disposal reinjection treatment process according to the present situation of oilfield site, and carried out experimental research. The results showed that the standards (SS<10 mg/L, oil content<30 mg/L, pH=6-9) could be reached by series of disposal methods, such as gel breaking, ferriccarbon microelectrolysis, flocculation and filter pressing. Aiming to meet the requirements of reinjection, experimental basis for design and implementation of treatment device and disposing of flowback fluid from unconventional fracturing were provided.
Key words: unconventional fracturing fluid, gel breaking, microelectrolysis, flocculation