Dec.2013,Vol.42,No.6
CHEMICAL ENGINEERING OF OIL & GAS
ABSTRACTS
International standardization developments of natural gas quality, analytical and test technologies
Luo Qin1,2,3,4, Ji Zhongli1, Xu Wenxiao2,3,4, Chen Xiaohong4,5(1.China University of Petroleum，Beijing 102200, China; 2. Research Institute of Natural Gas Technology, PetroChina Southwest Oil & Gasfield Company，Chengdu 610213, Sichuan, China; 3. Key Laboratory of Natural Gas Quality Control and Energy Metering, CNPC， Chengdu 610213, Sichuan, China; 4. China Natural Gas Standardization Technology
Committee Secretariat, Chengdu 610213, Sichuan, China; 5. Quality and Standard Management Department, CNPC, Beijing 100072, China).CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp549～554,2013（ISSN 1007-3426, IN CHINESE）
Abstract: International Organization for Standardization Natural gas Technical Committees(ISO/TC 193) is mainly engaged in standardization of terminology, quality specifications, methods of measurement, sampling, analysis and test for natural gas and natural gas substitutes (gaseous fuel) in all its facets from production to delivery to all possible end users across national boundaries. ISO/TC 193 also undertakes recognition of work related to natural gas in other technical committees. ISO/TC 193 has drafted and revised 43 international standards since its establishment. With the rapid development of Chinese natural gas industry, as well as the rapid growth of international trade of natural gas, the demands for standardization of natural gas quality and analytical techniques are also growing. This article focused on detailed analysis of the development of international standard system revision projects in natural gas quality specifications and analytical techniques of ISO/TC 193, and proposed the concerned ISO standard projects and our next work ideas, so as to lay foundation for improving our natural gas quality and analytical techniques standard system as soon as possible and accomplish the targets in line with the international standards.
Key words: natural gas, quality, analysis, international standardization
Pinch design method for heat exchanger networks based on the uniformity principle of temperature difference field
Wan Yiqun, Cui Guomin, Peng Fuyu, Xu Haizhu(Institute of New Energy Science and Engineering, University of Shanghai for science and technology, Shanghai 200093, China).CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp555～560,2013（ISSN 1007-3426, IN CHINESE）
Abstract: Traditional pinch design method of heat exchanger networks is improved, the composite curve is divided into several segments for individual treatment, the network of every segment using the uniformity factor of temperature difference of heat exchanger networks as the evaluation index is designed, the structures of every segment and the matches far form the pinch are combined into an integrated original heat exchanger network, the original structure using Newton method as regulation optimization is optimized, and an optimal cost heat exchange network finally is obtained. From a specific example, the heat exchanger network designed according to the uniformity principle of temperature difference field is of better heat transfer performance, the final annual cost is better than that of other literature, and the availability of this method is validated.
Key words: the uniformity principle of temperature difference, heat exchanger networks, pinch
Parameter optimization of natural gas processing plant of Tahe 1#
Wang Zhihong1, Li Zhi1, Ye Fan2, Zhang Yihua3(1. Southwest Petroleum University, Chengdu 610500, Sichuan, China; 2. Northwest Oilfield Branch, SINOPEC, Urumqi 830000, Xinjiang, China; 3.Natural Gas Development Company of Qinghai Oilfield,PetroChina, Golmud 816000, Qinghai, China).CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp561～566,2013（ISSN 1007-3426, IN CHINESE）
Abstract: Aiming at the actual situation of the natural gas processing plant of the Tahe 1#, this paper focused on the research of the sensitive factors that affect the natural gas processing plant and the optimization of the parameters. In this paper, the process simulation software was used to build a model, and the following factors were used to analyze their influences on the recovery of C3 and C3+ and the energy consumption of the facility. These factors include the outlet temperature from the expansion side of expansion unit, the temperature after propane refrigeration, the temperature of low-temperature separator, the number of theoretical plates of DHX tower and dethanizing tower, the temperature of reboiler at the bottom of dethanizing tower. Based on the variables above, using high recovery rate and low energy consumption as goals, LPG quality standards as constraint conditions, the paper successfully established the optimal model of natural gas processing facility with sequential quadratic programming method. As a result, the recovery rate of C3 has increased from 83.63% to 96.65% and the recovery rate of C3+ from 92.30% to 98.43%. At the same time, the molar content in the processed liquefied gas of C3+C4 has increased to 95%, and C5 has decreased about 1%.
Key words: natural gas, light hydrocarbon recovery, expander, parameter optimization
Application of mixed charge of molecular sieve dehydration and demercaptan process in Amu River natural gas treatment plant
Wang Jian, Cao Jie, Zhu Yiyun（Chongqing Natural Gas Purification Plant General, PetroChina Southwest Oil & Gasfield Company，Chongqing 401220, China）.CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp567～570,2013（ISSN 1007-3426, IN CHINESE）
Abstract: This paper describes the dehydration unit of No.1 natural gas treatment plant in Amu River, Turkmenistan. The dehydration and demercaptan process principle and optimal process of two different kinds of molecular sieves mixfilled in different layer of the same adsorption tower are introduced. At the same time, the advantages of molecular sieve applied in deeply dehydration & demercaptan are summarized.
Key words: molecular sieve, dehydration, demercaptan, Amu River, natural gas
Application analysis of TEG dehydration in sour gas gathering station
Luo Guomin(Northeastern Sichuan Sour Gas Project, PetroChina Southwest Oil and Gasfield Company, Dazhou 636164,Sichuan,China).CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp571～577,2013（ISSN 1007-3426, IN CHINESE）
Abstract: This article aims to explain the reason of applying TEG absorption in sour gas and introduce the process and feasibility of it. It also brings up suggestions to problems in production, operation and management, and provides references for the production and management of similar plants.
Key words: TEG, highly sour gas field, dehydration
Application of supersonic separation technology in natural gas dehydration
Jin Liang, Zhu Lin, Wang Lei(College of Chemistry and Chemical Engineering of Southwest Petroleum University, Chengdu 610500, Sichuan, China).CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp578～581,2013（ISSN 1007-3426, IN CHINESE）
Abstract: In order to meet the requirements of pipeline transportation and chemical industrial utilization, natural gas must be dehydrated. Supersonic separation is a new technology for natural gas dehydration, which has obvious advantages compared with the traditional techniques. This paper introduces the working principle of supersonic separation and the structure design of Laval nozzle, analyses the internal application statue of 3S in natural gas dehydration. Through the comparison，it is considered that 3S in parallel with J-T valve and then in tandem with molecular sieves is a best way for natural gas dehydration, which could meet the requirements of dehydration process of internal natural gas.
Key words: dehydration, supersonic separator (3S), Laval nozzle, principle, application prospect
Energy saving optimization measures of steam and condensation water of sulfur recovery unit in Wanzhou natural gas purification plant
Liao Tie1, Su Mengyao1, Li Fazhang2, Fan Qin1(1.Wanzhou Branch of Chongqing Natural Gas Purification Plant General, PetroChina Southwest Oil & Gasfield Company, Chongqing 404001,China;2. Research Institute of Natural Gas Technology, PetroChina Southwest Oil & Gasfield Company, Chengdu 610213, Sichuan, China).CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp582～587,2013（ISSN 1007-3426, IN CHINESE）
Abstract: Based on the composition analysis of steam and condensation water of sulfur recovery unit in Wanzhou branch of Chongqing natural gas purification plant, this paper discussed these optimization measures. The steam ejector was redesigned to realize the application of stream cascading and the methods are used to realize the airtight recycling of condensation water such as recovering steam discharged from the condensation tank，recycling condensation water，recovering condensation water at partial pressure and optimizing the type of steam traps. The comprehensive energy consumption can be reduced from 1 303.38 MJ to 1 188.23 MJ per 1×104 m3 containing 1%(mol) of H2S after optimization. Compared with the design which consumes 2 010 MJ per 1×104 m3 containing 1%(mol) of H2S, the effect of energy saving is obvious.
Key words: steam, condensation water, optimization, energy saving, sulfur recovery
Cold energy utilization in satellite LNG regasification plant
Chen Gengliang(Research Institute of Natural Gas Technology, PetroChina Southwest Oil & Gasfield Company,Chengdu 610213,Sichuan,China).CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp588～593,2013（ISSN 1007-3426, IN CHINESE）
Abstract: Although the problem of cold energy utilization of LNG regasification has aroused global attention, most of these techniques are still in their early stages and only for large plants. Satellite plants can only supply small amount of cold energy, but its quality is very good. It is an economical and effective way to utilize this energy for building cold storage. The first demonstration project of China is the Xingtan Cold Storage built in Foshan City of Guangdong Province and its successful experience is worthy of attention. If the energy is used for car air conditioning system and refrigerated vehicles, the cold energy would be recovered at a maximum extent and exhaust emission can be reduced at the same time. Even new techniques mentioned above are not commercialized at present, their advances are ascendant at home and abroad.
Key words: liquefied natural gas (LNG), cold energy utilization, satellite regasification plant, cold storage, car air conditioning system
Phase equilibrium calculation method of gas hydrate in constant volume process
Chen Peng, Li Yuxing, Wang Wuchang, Liu Haihong, Zhang Qingdong(College of Pipeline and Civil Engineering, China University of Petroleum (East China), Qingdao 266580, Shandong, China) .CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp594～597,2013（ISSN 1007-3426, IN CHINESE）
Abstract: Based on Chen-Guo model, hydrate formation process analysis and a well comprehension of two-phase flash calculation, this article proposed a calculation process of phase equilibrium state of hydrate slurry preparation process under constant volume. This method is of great importance for prediction of hydrate slurry preparation and calculation of slurry properties.
Key words: hydrate, phase equilibrium, hydrate slurry preparation, experiment process
Application analysis of by pass pigging for gas-condensed pipeline
Zhu Haishan, Luo Xiaoming, Yao Haiyuan, He Limin,Li Qingping
(Oil Research Institute China National Offshore Oil Company, Beijing 100027, China).CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp598～601,2013（ISSN 1007-3426, IN CHINESE）
Abstract: There are some problems such as a large amount of liquid slug existing and the difficulty of pig's speed control when the pipeline pigging operations are conducted by traditional pig. Recently, by pass pigging is becoming the key innovation technology because it can effectively reduce liquid slug and realize redistribution of the chemicals such as corrosion inhibitors. In this paper, on the basis of the by pass analyses technology, the gas-condensed submarine pipeline pigging model is set up by using the multiphase flow dynamic simulation software OLGA, and the effects of the pipeline parameters, operating conditions, and the seabed environment to the by pass pigging are simulated. On this base, the comparisons between the traditional pigging and the by pass pigging have been done through the changes of pigging velocity, pressure, and liquid slug etc. Meanwhile the optimum by pass rate is obtained which provides guidance for the practical applications of by pass pigging.
Key words: bypassed pig, by pass rate, velocity, pressure, liquid slug flow
Corrosion effects research of M15 methanol-gasoline on copper
Huang Yong, Zhang Juanli，Zhang Shuqin（Institute of Shaanxi Yanchang Petroleum(Group) Co. Ltd, Xi'an 710075，Shaanxi，China）.CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp602～606,2013（ISSN 1007-3426, IN CHINESE）
Abstract: Based on the experiment of hanging out the test block by static state, the corrosive mechanism for metal material of methanol gasoline was discussed. The corrosion effects of temperature, water, content, oxygen content, and acid number on copper in M15 methanol-gasoline were investigated, and the corrosion mechanism of the inhibitor was analyzed. Through optimizing and formulating the inhibitor, the anti-corrosive experiment of M15 methanol-gasoline was conducted. The results showed that when the addition of benzotriazo was 0.05%(wt), the copper had a better anticorrosive performance that the corrosion rate of brass and red cupper were 0.414 g/m2 and 0.638 g/m2 respectively, which reduced about 10%~30%.
Key words: M15 methanol-gasoline, corrosive mechanism, inhibitor
Magnified preparation of catalyst and deactivation mechanism study of syngas methanization
Liu Zhihong1,Xu Yarong2, Xu Xinliang2, Liu Ping3 (1. Technology Management Department of PetroChina Natural Gas Co.Ltd, Beijing 100007, China; 2. Research Institute of Urumqi Petrochemical Company, Urumqi 830019, Xinjiang, China; 3. Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030002, Shanxi, China).CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp610～613,2013（ISSN 1007-3426, IN CHINESE）
Abstract: Magnified preparation of the catalyst was studied in this paper. Activity and stability of the catalyst were evaluated through long period, and deactivation mechanism of the catalyst was studied. The study result showed that average conversion of CO and H2 reached 99.9% and 99.8% respectively, average selectivity of CH4 attained 98.5%, and the activity of application catalyst was stable after continuous running of 1 000 hours. Deactivation mechanism study of the catalyst showed that the causes of catalyst deactivation with long period operation were carbon deposition and sintering, in which sintering is the main factor resulting in the decrease of catalyst activity.
Key words: methanization, catalyst, magnified preparation, deactivation, mechanism
Commercialization of sulfolane extractive distillation process in Qinqyang petrochemical company
Li Junkui1，Zhang Zhentai1， Yu Xinwen1， Xu Jia1, Wu Zhanyong2
(1.PetroChina Qingyang Petrochemical Company, Qingyang 745002, Gansu, China; 2. PetroChina Ningxia Petrochemical Company, Yinchuan 750021, Ningxia, China）.CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp452～456,2013（ISSN 1007-3426, IN CHINESE）
Abstract: The sulfolane extractive distillation process is successfully commercialized in benzene extraction unit with a production capacity of 100×103 t/a in Qingyang Petrochemical Company. The operation results show that the purity of benzene is 99.95％，the crystallizing temperature of benzene is above 5.4 ℃, the recovery efficiency is 99.81％ and the energy consumption is 19.35 kgE0/t. Besides, some problems during the operation, such as extractive distillation flooding，removal of C6 tower energy waste, white earth inactivation are analyzed, and the solutions are carried out.
Key words: benzene, sulfolane, extractive distillation, white earth inactivation
Adaptability evaluation of formate solution to saturated brine sulfonated drilling fluids
Ye Yan1, An Wenhua2, Yin Da2, Zhao Shanshan1, Liang Hongjun2, Lu Hu2, Li Lei2（1. China University of Petroleum (Beijing),Beijing 102249,China; 2. PetroChina Tarim Oilfield Company, Karamay 834000, Xinjiang,China）.CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp614～618,2013（ISSN 1007-3426, IN CHINESE）
Abstract: Potassiumbased solution with high concentrations is brought into saturated brine sulfonated drilling fluid in the complex ultra-deep wells, which can reduce the solid content of highdensity drilling fluid, improve the thermal stability of the drilling fluid, temperature resistance of key treatment agents and the drilling speed in the extremely thick ultra-deep salt formation, and slow down the drilling corrosion. At the same time, formate drilling fluids have the advantages of inhibitive ability, good quality of mud cake, low annular pressure lost and friction coefficient. This article discussed the solubility of barite in potassium formate solution and its tolerance to salt and calcium. The experimental results showed that barite was almost insoluble in potassium solution so that the formate solution of 30%～70% was used to improve the density of base fluid and then choosing barite to aggravate it was feasible. In addition, the solubility of sodium chloride and gypsum in formate solution both reduced by different degrees, which could be used to further increase the tolerance to salt and calcium of sulfonated drilling fluid.
Key words: saturated brine sulfonated drilling fluids, formate base fluid, barite, tolerance to salt and calcium
Application evaluation of formation protection techniques in BH oilfield
Zhou Yuxia1, Li Xiaojun2, Wu Zhenyu3(1. College of Petroleum Engineering, Yangtze University, Wuhan 430100, Hubei,China; 2. Shandong Kerui Oil and Gas Company, Dongying 257000, Shandong, China; 3. Oil Production Plant of Yanchang Oil Field, Xi′an 719100, Shaanxi, China).CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp619～623,2013（ISSN 1007-3426, IN CHINESE）
Abstract: Reservoir clay mineral form analysis and reservoir sensitivity experiments showed that the plugging of extrinsic solid-phase particle and scaling in oil-well were main reservoir damage types in BH oilfield. All kinds of fluid in the well, such as completion fluid, kill-fluid and perforating fluid should be free solid or low solid fluid with low filter loss or leakage and good compatibility with formation and formation fluid. Formation protection effectiveness of all kinds of using completion fluid, kill-fluid and perforating fluid indicated that the completion fluid(polymer sulfonated drilling fluid + 2%～3% oil soluble temporary plugging agent) used largely can meet the need of reservoir protection, and kill-fluid or perforating fluid are composed of free water, 0.5%～1% clay stabilizer and 0.2% thickening agent, when formation pressure coefficient is less than 1, 1%~3% oil soluble temporary plugging agent should be added to prevent loss of pressure well liquid to formation.
Key words: formation protection，completion fluid，kill-fluid，perforating fluid，clay mineral form, reservoir sensitivity
Determination of miscibility conditions by vanishing interfacial tension between CO2 and crude oil
Peng Baozi1, Zhang Qian2(1. National Institute of Clean and Low Carbon Energy, Beijing 102209, China; 2. CNOOC Research Institute, Beijing 100027, China).CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp624～628,2013（ISSN 1007-3426, IN CHINESE）
Abstract: Injecting recovered CO2 from fuel gases into the reservoir crude oil at or near the condition of miscibility is one of the main methods to realize CO2 sequestration and utilization. Minimum miscibility pressure (MMP) is often considered as a key parameter for the design of a gas injection project. In this paper, the interfacial tension between CO2 and four kinds of reservoir crude oil were measured by the pendant drop method at stratum temperature, and the MMPs for the four kinds of reservoir crude oil were determined directly with visually observed miscibility appearance as 24.12 MPa, 24.81 MPa, 26.87 MPa and 31.69 MPa, respectively. At the same time, the polynomial extrapolation method was also used to determine their MMPs. The results showed that the error of MMPs determined by polynomial extrapolation method was within 3%, and corresponding to lower error value at higher MMP. It indicated that MMP determined by vanishing interfacial tension had the advances of low error and cost, convenience and easy operation.
Key words: carbon dioxide, interfacial tension, oil displacement, miscible phase, minimum miscibility pressure
Influence of clay particle on stability of emulsion
Cao Dongqing, Kang Wanli, Meng Xiangcan, Zhang Kaibo,Liu Shuren, Yang Runmei(Department of Petroleum Engineering, China University of Petroleum (East China) ).CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp629～632,2013（ISSN 1007-3426, IN CHINESE）
Abstract: The influence of clay particle on Jilin oil emulsion and oil-water interfacial property has been studied through dynamic model analysis, Turbiscan stability analysis and single drop method. The results showed that the dynamic reaction rate constant of system first increased then decreased, and the stability of emulsion first increased then decreased as the concentration of clay particle improved. It also showed that back scattered light of emulsion decreased less, and coagulation stability of system increased with addition of clay particle, which promoted drain and coalescence of droplets as joint medium. At the same time, it showed that drain time of droplets and survival half life increased, fracture velocity constant decreased and strength interfacial film improved because of adsorption of clay particle.
Key words: clay particle, emulsion, stability, dynamical features, interfacial film
Effect evaluation of chemical paraffin control in Baibao oilfield
Yang Huili1,2, He Zhiwu1,2, Liu Aihua1,2, Liu Baowei3, Liu Xinyin3(1. Oil & Gas Technology Research Institute of Changqing Oilfield Company, Xi′an 710021，
Shaanxi，China;2. National Engineering Laboratory for Low Permeability Petroleum Exploration and Development, Xi′an 710021，Shaanxi，China; 3.The Seventh Oil Production Plant of Changqing Oilfield, Wuqi 710021，Shaanxi,China).CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp633～636,2013（ISSN 1007-3426, IN CHINESE）
Abstract: Solid paraffin inhibitor can inhibit wax deposition on the tube, rode, pump in paraffin troubled well, prolong the pump inspection cycle and reduce energy consumption of pumping unit. The effect of wax prevention was evaluated by changing paraffin inhibiting ratio and wax precipitation point with oil wax deposition rate tester and dynamic rheometer. The relation of pump inspection period, dissolving rate and paraffin inhibiting ratio was calculated, which could predict effect of paraffin inhibitor in the bottom of oil well. System efficiency tester was used to test the electric parameter through the pumping unit motor operation and the load with the sensor installed on the beam hanger of pumping unit. Paraffin control effect was evaluated according to the diagrams tested in paraffin troubled well. The results of field tests showed that the loading of oil well could be lower 9.73 kN by solid paraffin inhibitor, the system efficiency raised 6.92% and integrated energy-saving rate was 22.23%.
Key words: paraffin deposition, solid paraffin inhibitor, paraffin inhibiting ratio, wax precipitation point, Baibao oilfield
Correlation of polar fractions of heavy oil with its viscosity and reverse phase point of emulsion
Wang Feng1，2, Li Meirong3, Qi Linyan3(1. School of Petroleum Engineering，China University of Petroleum(Beijing)， Beijing 102249, China; 2. SINOPEC Shengli Oilfield Branch Company，Dongying 257001, Shandong, China; 3. College of Science，China University of Petroleum(East China)， Qingdao 266580，Shandong, China).CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp67～641,2013（ISSN 1007-3426, IN CHINESE）
Abstract: The correlation between the contents and properties of polar fractions and the viscosity of heavy oil were studied by gray correlation entropy method．By changing volume fraction of water and temperature of the emulsions of heavy oil, the relation between the composition property of heavy oil and the reverse phase point were also researched. The result showed that the order of correlation degree between the polar fractions and the viscosity of heavy oil was: asphaltene>resin>aromatic>saturate; and the order of correlation degree between the mean dipolemoments of polar fractions and the viscosity of heavy oil was: asphaltene>resin>aromatic. In addition, as the increase of the contents of the resin and asphaltene, the decrease of the interfacial tension of oil-water, and the increase of Zeta absolute value of oil drops, the volume fraction of water and temperature at the reverse phase point of emulsion gradually raised.
Key words: polar fractions, dipole moments, viscosity of heavy oil, emulsion, reverse phase point
Study on natural gas interchangeability discriminant method
Zhou Li1,2, Guo Kaihua1,Huangfu Lixia1 ,Gao Wenxue3, Xu Wenxiao2(1. School of Engineering of Sun Yat-Sen University, Guangzhou 510006, Guangdong，China; 2. Research Institute of Natural Gas Technology of PetroChina Southwest Oil & Gasfield Company, Chengdu 610213,Sichuan,China; 3. China Quality Supervising and Test Center for Gas Appliance (CGAC), Tianjin 300000,China).CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp642～646,2013（ISSN 1007-3426, IN CHINESE）
Abstract: This paper reviewed the research progress of natural gas interchangeability in European and American countries and regions, and summarized that the commonly used gas interchangeability methods in the world, which are AGA Bulletin 36 method, Weaver indices method in US, Delbourg method in France, Dutton Diagram method in UK, ect. These methods are all developed for atmospheric combustion, with respective applicability and limitation. In China, the town gas was categorized and defined by composition according to France Delbourg interchangeability method in 1982. The paper also summarized the research and progress on gas interchangeability in recent years in China, and indicated that with the diversification of the fuel gas terminal equipments, the desirable and scientific gas interchangeability indices and gas distribution control parameters could be studied and chosen according to the specific gas combustion equipment, and based on the difference of mixed modes of gas and air when burning.
Key words: natural gas, interchangeability, Wobbe index, combustion potentia
Determination of trace sulfur in synthetic gas by gas chromatography and sulfur chemiluminescence detector
Si Ruigang1, Zhou Long2, Chang Jingzhi2(1. Xindi Energy Engineering Co.,Ltd, Beijing Research and Development Center,Beijing 100176,China；2. Henan Jingbao ENN New Energy Co.,Ltd,Pingdingshan 467000,Henan, China).CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp647～653,2013（ISSN 1007-3426, IN CHINESE）
Abstract: Because of environmental pressures and market demands, the project of making LNG from coke oven gas was applied widely. In order to increase the service life of synthesis catalysts, the contents of total sulfur in synthetic gas must be strictly controlled, which should be lower than 50×10-9(volume fraction).The GC＆SCD method was applied to determine the content of trace sulfide and total sulfur in synthesis gas，and the influence factor was explained in the process of analysis and sampling. The detection limit of the method for every sulfur form is less than 10×10-9(volume fraction)，and total sulfur is 33×10-9(volume fraction). The correlation coefficient of calibration curves for every sulfur form is better than 0.996 and RSD is less than 7%. During analysis of synthesis gas, the RSD is less than 12%. The demands of process control can be satisfied well.
Key words: GC, SCD, coke oven gas, synthesis gas, sulfur forms, total sulfur, LNG
Field study of oily sludge treatment in Yanchang oilfield
Yang Zhigang, Liu Li, Wei Yanlin(Research Institute of Shaanxi Yanchang Petroleum（Group）Co.,Ltd, Xi'an 710075,Shaanxi,China).CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp654～657,2013（ISSN 1007-3426, IN CHINESE）
Abstract: Yanchang oilfield is located in arid and water-scarce areas. The ecological environment of this region is deteriorating and the pollution caused by the oily sludge is serious. The oily sludge was treated in some oil production plant of Yanchang oilfield by hot wash→ three-phase separator →pressure filter→solidify technology route. Hot wash was propitious to remove oil from oily sludge，and the removal rate could be more than 90%. The compressive strength of brick made from sludge which treated by pressure filter was more than 10 MPa, and the COD of leaching solution reached emission standards. The brick could be used for the construction of well site. This technology realized harmless treatment and resource utilization of oily sludge.
Key words: oilfield, oily sludge, hot wash, solidify, site test
Engineering design of explosion protection in LNG receiving terminal
Yin Hong（CNOOC Gas and Power Group Research & Development Center，Beijing 100007,China）.CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp658～662,2013（ISSN 1007-3426, IN CHINESE）
Abstract: Explosionproof security is the top priority of the enterprise in the gas industry, terminal corresponding measures must be taken in engineering design in the liquefied natural gas (LNG) receiving terminal.This paper discusses environment characteristics and harms of the LNG receiving terminal explosion, as well as the determination of release source, summarizes the risk zoning dividing method and expounds commonly used explosion-proof measures of the LNG receiving station, such as the explosion-proof design of the structure, ventilation design, the selection of explosion-proof electrical equipment, etc., then concludes the explosion-proof design characteristics of domestic LNG receiving terminal engineering, and proposes the reference suggestions to the subsequent project construction.
Key words: LNG, LNG receiving terminal, LNG leakage, risk zoning division, explosion-proof measures
Layers of Protection Analysis (LOPA) method and application of risk analysis
Li Na, Sun Wenyong, Li Jiayi(China National Petroleum Corporation Research Institute of Safety & Environment Technology, PetroChina Science Park, Beijing 102206,China).CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp452～456,2013（ISSN 1007-3426, IN CHINESE）.CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp663～666,2013（ISSN 1007-3426, IN CHINESE）
Abstract: The CNPC has advanced the Hazard and Operability Analysis (HAZOP) method on several refinery enterprises in recent years. The Layers of Protection Analysis (LOPA) method is integrated into the HAZOP on the basis of that there is still existing insufficient on HAZOP. The LOPA can realize semiquantitative evaluation of risk by means of HAZOP results. This article introduces the concept of LOPA, occasion of using LOPA, what are the layers of protection and the Independent of Protection Layers (IPLs), the procedure of LOPA, the advantage and limitation of LOPA, and so on. Through an example of carrying on the LOPA on the results of HAZOP, the work is listed in details step by step according to the procedure of LOPA.
Key words: layers of protection analysis (LOPA), independent protection layers (IPLs), risk
Combined treatment of acidification-coagulation-catalytic oxidation of drilling waste
Du Guoyong, Huang Rong, Zeng Yang（Chemistry and Chemical Engineering Institute, Southwest Petroleum University, Chengdu 610500, Sichuan,China）.CHEMICAL ENGINEERING OF OIL & GAS, VOL.42, NO.6,pp667～670,2013（ISSN 1007-3426, IN CHINESE）
Abstract: The drilling wastewater from oil and gas field has been a problem of environmental risk for oil field management. In this experiment, the oilfield drilling wastewater was put as the research object, in which the COD value reached up to 67 920 mg/L. The preparation of a new coagulant PAZC and optimum conditions of chlorine dioxide catalytic oxidation process by acidification-coagulation-catalytic oxidation process were mainly researched. The COD value could be reduced to 126.9 mg/L after treatment and achieved the secondary discharge standard of “Integrated Wastewater Discharge 8978-1996”.
Key words: drilling waste, acidification, coagulation, catalytic oxidation, combined treatment
