Oct.2014,Vol.43,No.5
CHEMICAL ENGINEERING OF OIL & GAS
ABSTRACTS
Optimization of desulphurization system for increased acidic components content in natural gas
Fan Zheng1, Liu Xiangying1, Huang Fenglin1, Li Wenhong2, Qiao Yulong3, Yan Zhao3(1. College of Chemistry & Chemical Engineering, Xi’an Shiyou University, Xi’an 710065, Shaanxi, China; 2. College of Chemical Engineering, Northwest University, Xi’an 710069, Shaanxi, China; 3. The First Gas Plant, Changqing Oilfield, Yulin 718500, Shaanxi, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp467-471,2014（ISSN 1007-3426, IN CHINESE）
Abstract: Aiming at the inferior product gas quality and frequent equipment troubles due to the increase of acidic components content in natural gas in recent years, the process of desulphurization system after the increase of MDEA solution circulation flow rate was simulated by Aspen HYSYS software. The simulation result demonstrated that it was necessary to increase MDEA solution volume flow rate gradually from 63.25 m3/h to 102.85 m3/h to satisfy national standards when the volume fraction of CO2 and H2S was increased from 5.280% and 0.028% to 6.280% and 0.052% respectively. Key facilities were implemented a series of optimization by the professional softwares of FRI-Tray Rating, and HTRI Xchanger Suite, etc. The fluid mechanics performance of amine absorber and regenerator were qualified for different volume flow rates of MDEA solution after calculation. When the volume flow rates increased, it was feasible schemes to add the same model of lean/rich amine heat exchanger in series and simultaneously change the specification of heat exchange tube to meet the demand and resolve block. Optimized two-level flash device could greatly relieve frequent fluctuation and fixing the high-efficiency corrugated plate demister at inlet could avoid system foaming.
Key words: natural gas,desulphurization,H2S,CO2,MDEA,flowsheet simulation
Influence of various factors on the corrosion of MDEA solutions
Jiang Jingjing1,2,3, Ren Ting4, Zhang Qiang1,2,3, Chang Honggang1,2,3, Lei Yu4, Liu Xuan4, Song Mengqiu4(1. Research Institute of Natural Gas Technology, PetroChina Southwest Oil & Gasfield Company, Chengdu 610213, Sichuan, China; 2. National Energy R&D Center of High Sulfur Gas Exploitation， Chengdu 610000，Sichuan, China; 3. High Sulfur Gas Exploitation Pilot Test Center， CNPC， Chengdu 610213， Sichuan， China； 4. Central Sichuan Oil and Gas District, PetroChina Southwest Oil & Gasfield Company, Nanchong 637648, Sichuan, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp472-477,2014（ISSN 1007-3426, IN CHINESE）
Abstract: The corrosion behaviors of four metal materials in MDEA solution at different conditions were studied by electrochemical methods. The results showed that with increasing temperature, electrochemical corrosion rate increased dramatically. Moreover, the corrosion rate of 20# steel and 20R steel in vapor phase was greater than that in liquid phase. The corrosion rates of amine solution saturated with hydrogen sulphide increased after running for a period, while the solution without hydrogen sulphide showed almost no electrochemical corrosion to the materials. In addition, the tendency of electrochemical corrosion of stainless steel 304 and 316L was not detected during the experiment.
Key words: natural gas, MDEA solution, corrosion, heat stable salts (HSS), hydrogen sulphide
Process and application of tail gas treatment for SSR sulfur recovery
Zhang Li, Xiao Hongliang（Sinochem Quanzhou Petrochemical Co., Ltd, Quanzhou 362103, Fujian, China）. CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp478-482,2014（ISSN 1007-3426, IN CHINESE）
Abstract: In recent years, as the situation of environment becomes serious and the consciousness of environmental protection is enhanced, more strict standards for pollutants discharge were issued. The emission requirements of tail gas from sulfur recovery unit are accordingly improved, which further promote the development of the tail gas treatment process. SSR is a tail gas treatment technology with both environmental and economic benefits. The SSR technology and other four kinds of reduction-absorption technology, which include SCOT, Super SCOT, RAR and HCR, are compared. The principle, technical characteristics and application in different sulfur recovery devices are mainly introduced, and the application prospect is forecasted.
Key words: reduction-absorption process, SSR, sulfur recovery, tail gas treatment, environmental protection
Energy-saving design of capacity expansion revamping for CCR unit
Yuan Chunhua, Ren Jiansheng(CPECC East-China Design Branch (Beijing), Beijing 100101, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp483-486,2014（ISSN 1007-3426, IN CHINESE）
Abstract: Relying on the capacity expansion and revamp of 400×103 t/a CCR unit built in the 1990’s, a series of energy saving measures were taken considering the scale, process and energy utilization, which include: optimizing the feed scheme according to the characteristics of the feed to reduce the scale of reaction; utilizing the high-efficient welded plate heat exchanger and double shell side heat exchanger to enhance heat transfer; decreasing the outlet temperature of flue gas to increase thermal efficiency of heating furnace; and optimizing the heat exchanger process flow to lower the inlet temperature of air cooler, and maximizing to utilize the latent heat of evaporation in the top of the tower. As a result, the processing ability increased by 13%, while the comprehensive energy consumption decreased by 502.4 MJ/t.
Key words: continuous catalyst reforming, capacity expansion, energy-saving design
Counter measures for extending regeneration cycle of SHY-DL-1 C4 hydroaromatization catalyst
Yang Desheng, Chen Yuanchun(Puyang Hengrun Statebuilding Petrochemical Co., Ltd，Puyang 457600, Henan, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp487-491,2014（ISSN 1007-3426, IN CHINESE）
Abstract: There are many factors affecting regeneration cycle of C4 aromatization, which relate to the stability of production device operation and economic benefits of enterprises. Various key factors and measures of prolonging the regeneration cycle of the catalyst were introduced. The production inspection was carried on the 200×103 t/a C4 hydroaromatization device of Puyang Hengrun State Building Petrochemical Co. Ltd. The results showed that by optimizing the quality of raw materials and process operating conditions, it could effectively prolong the regeneration cycle of the catalyst. The practice showed that the regeneration cycle could be extended from 90 days to 183 days, and had a good stability, so that the catalyst regeneration cycle exceeded the design value, and the economic benefits of the device was improved.
Key words: C4, hydroaromatization, catalyst, regeneration cycle
Optimal operation of MDEA regeneration system in natural gas purification plant
Tang Xi, Qu Yang, Chen Tingku, Hou Guangyuan, Zhang Yunguang（Chongqing Natural Gas Purification Plant General, PetroChina Southwest Oil & Gasfield Company， Chongqing 401259， China）. CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp492-496,2014（ISSN 1007-3426, IN CHINESE）
Abstract: Serving as the critical equipment of solution regeneration system in 2 800×103 m3/d MDEA desulfurization unit in Yinjin Branch of Chongqing General Natural Gas Purification Plant, the solution circulation pump has an unstable outlet pressure. The system interlock shutdown due to the sudden drawdown of pump outlet flow rate occurred frequently. The process, equipment and pipeline layout were analyzed, and the results showed that excessive elbows were not the main reasons of system pressure drop. The layout of Π type pipeline would reduce the pressure and result in the evolution and accumulation of acid gas, thereby leading to the suction of MDEA circulation pump and the fluctuation of pump outlet pressure, which would bring great influence to the operation of system.
Key words: natural gas, desulfurization, MDEA, solution regeneration, pressure drop, optimization
Experimental study of the ANG storage tank during charge and discharge
Zheng Qingrong, Zhu Ziwen, Luo Wanzhen(Provincial Key Laboratory of Naval Architecture & Ocean Engineering, Institute of Marine Engineering, Jimei University, Xiamen 361021, Fujian, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp497-500,2014（ISSN 1007-3426, IN CHINESE）
Abstract: Comparative experiments were carried out to develop an adsorbed natural gas (ANG) storage tank for replacing a domestically used liquefied petroleum gas (LPG) tank. Coconut shell activated carbon SAC-02 with SBETof 2 074 m2/g was selected as an adsorbent. A cylindrical steel pressure vessel, which was respectively equipped with a helical heat exchanging pipe, a U-shaped pipe and a perforated tube, was used to evaluate the effect of the cooling/heating water and the charge/discharge patterns on temperature fluctuation of the adsorbent bed and the charged/discharged amount of the storage tank. Tests were undertaken at ambient temperature, under pressure of 3.5 MPa and the flow rate 15 L/min of the natural gas. It shows that, about 10 ℃ fluctuation of temperature at the central region of the storage tank has been cut down by circulating the cooling/heating water along the helical pipe instead of the U-shaped pipe, and the total charged/discharged amount of the gas from the vessel has also correspondingly increased by about 18% and 14%, respectively. Charging/discharging the gas through the perforated tube can reduce the temperature fluctuation amplitude about 15 ℃ and 10 ℃, respectively, but the total amount of gas charging /discharging from the vessel has been decreased by 2% and 7%. It suggests that the running water at ambient temperature is an effective medium for managing the thermal effect of a domestically used ANG vessel in the charge/discharge process, and conformable design of the vessel should be undertaken by optimization among the measures of introducing supplemental heat, heat and mass transfer enhancement of the adsorbent as well as the charge/discharge methods.
Key words: adsorbed natural gas(ANG)，activated carbon，cooling water，perforated tube，helical tube
Application of medium-sized single capacity LNG storage tank in Zhuhai natural gas liquefaction plant
Yuan Qing, Jiang Weiqiang(CNOOC Guangdong Liquefied Natural Gas Company Limited, Zhuhai 519060, Guangdong, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp501-504,2014（ISSN 1007-3426, IN CHINESE）
Abstract: Single capacity LNG storage tanks are widely used in small and medium-sized natural gas liquefaction plants. The cost of tank is low, but the security is poor. The discretion of the static daily evaporation rate and whether the pressure control system can control the tank pressure within the normal range are the important characterization to evaluate the performance of single capacity tank. Zhuhai LNG plant includes two medium single LNG storage tank with the same size, based on the practical operation of the device, the change of static daily evaporation rate with filling level were measured, the cause of the rapid change of the tank pressure was analyzed, and the control effects of pressure control systems were demonstrated.
Key words: LNG, storage tank, single capacity, liquefied natural gas, static daily evaporation rate, pressure control
Operation efficiency and cost check of energy consumption of submerged combustion vaporizer
Jiao Yueming1, Chen Shuai2, Yang Li1, Zhou Hua2, Wang Zhe2, Li Qiang2(1.Xinjiang Hualong Oilfield Technology Company Limited; 2.PetroChina Dalian Liquefied Natural Gas Company Limited). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp505-511,2014（ISSN 1007-3426, IN CHINESE）
Abstract: Submerged Combustion Vaporizer (SCV), as an equipment with the highest operating costs of LNG terminal, its calculation of operation efficiency and cost check of energy consumption are of much concern. Therefore, firstly, the enthalpy of inlet LNG and outlet NG of SCV was obtained based on BWRS function. Then, based on enthalpy calculation, according to Secant Iteration Method to confirm the temperature of fuel gas achieved from transportation high-pressure natural gas through adiabatic buck, the energy consumption supplied by fuel gas heater is obtained. Afterwards, the calorific value of fuel gas is calculated and according to the law of energy conservation, efficiency and energy costs of SCV are acquired. Finally, in order to facilitate the use of LNG terminal, this calculation method is designed to a calculation software to meet the needs; simultaneously, its reliability with the actual operating data and examples of costing accounting of energy consumption are verified. The results proved that the software can calculate SCV operation efficiency and energy consumption accurately, and provide help and guidance for SCV operation and calculation.
Key words: submerged combustion vaporizer，LNG terminal, operation efficiency，energy consumption，cost check，BWRS function，calculation software
Utilization of pipeline pressure energy in Qianwei LNG plant
Li Junfang, Tan Jingming, Zhang Ruichun, Li Jiaolin, Gou Wenyu, He Wei(Chengdu Natural Gas Chemical Plant General, PetroChina Southwest Oil﹠Gasfield Company, Chengdu 610213, Sichuan, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp512-514,2014（ISSN 1007-3426, IN CHINESE）
Abstract: The technological process of Qianwei LNG plant is briefly introduced. Because of the high pressure energy of pipeline, the LNG plant has the technology characteristics of simple technological process, low energy consumption of refrigeration, and low liquefied rate, etc. The main factors which influence the expander refrigeration of natural gas are discussed, and the effect series of natural gas expander, the content of heavy hydrocarbon in natural gas and precooling will have a significant effect on refrigeration.
Key words: LNG, pipeline pressure energy, utilization
Re-fracturing technology research and field application of mixing water volume fracturing in ultra-low permeability reservoir
Li Jianshan1, Lu Hongjun1, Du Xianfei1, Qi Yin1, Gu Yanling1, Shi Cheng’en2, Ling Yonggang2（1.Research Center for Ultra-low Permeability Reservoirs of PetroChina Changqing Oilfield Company, Xi’an 710021,Shaanxi, China; 2. No. 2 Project Department for Ultra-low Permeability Reservoirs of PetroChina Changqing Oilfield Company, Xi’an 745100, Shaanxi, China）. CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp515-520,2014（ISSN 1007-3426, IN CHINESE）
Abstract: Single well has low yield in Huaqing low permeability oilfield. The wells with daily output less than 1 tons account for a larger proportion of total wells, reaching 56.2% in Huaqing Oilfield. Re-fracturing is an important measure to improve the production of fractured wells in Changqing ultra-low permeability reservoirs. Currently, the re-fracturing well stimulation is not ideal by using the conventional technologies. The performances such as small yield increase, water cut rising, production decline suddenly, short increasing period are appeared after re-fracturing. In this paper, the hybrid slick water SRV and multi-stage temporary blocking fracturing are combined to work for old production wells in ultra-low permeability reservoirs. Considering the well pattern and injection well conditions, the theories of volumetric fracturing and multi-stage temporary blocking are combined. After the parameters optimization in the laboratory and application of nine wells in the field, the average single well daily output increased 2.81 t, the effective production period for average single well is up to 252 days, and the effect of increasing yield is significant. The successful application of this technique also provides a strong basis for the re-fracturing in ultra-low permeability reservoir.
Key words: re-fracturing, volume fracturing, mixing water fracturing, increase production mechanism
Development and evaluation of high temperature emulsified acid
Yuan Li1, Xiong Ying1, Jiang Yong2, Zhang Qian1（1. Research Institute of Natural Gas Technology, PetroChina Southwest Oil & Gasfield Company, Chengdu 610213,Sichuan, China; 2.Production Operations Department，PetroChina Southwest Oil & Gasfield Company, Chengdu 610051, Sichuan, China）. CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp521-524,2014（ISSN 1007-3426, IN CHINESE）
Abstract: With the deepening of exploration and development of high temperature reservoir，Sichuan and Chongqing areas are facing to broaden and promote high temperature reservoir acid technology. The high temperature emulsified acid, with heat resistance of 140 ℃, has been developed through the research of new emulsifier CT1-36 which consists of ester containing unsaturated double bond and sorbitan monooleate. The high temperature emulsified acid had high oil acid interface intensity and large contact area of lipophilic group. Stability, rheological properties in high temperature, shear performance, reaction rate, corrosion rate and compatibility performance have been researched in laboratory. Laboratory results showed that the high temperature emulsified acid could stabilize more than one hour at 140 ℃，the viscosity reached 40 mPa·s after shearing for 60 minutes at 140 ℃ and 170 s-1, the reaction rate was 25 times slower than conventional acid, the viscosity of reacted acid was less than 10 mPa·s, and the compatibility with crude oil was good.
Key words: emulsified acid, high temperature, stability, retarded acid, reaction rate
Development of a multi-component thermal fluid corrosion monitoring device and its application evaluation
Ma Zenghua, Sun Yongtao, Lin Tao, Liu Haitao, Sun Yubao, Wang Shaohua(COSL Production Optimization Division, Tianjin 300450, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp525-528,2014（ISSN 1007-3426, IN CHINESE）
Abstract: Corrosion is the key factor restraining the promotion of multi-component thermal fluid technology. High temperature corrosion inhibitor has good protective effect, but the main corrosion rate could not be gotten. Hereto. a corrosion monitoring device is developed by placing two P110 coupons in the thermal fluid injection tube. After multi-component thermal fluid recovery for ten days，the corrosion is uniform, average corrosion rate is 0.090 5 mm/a, and the main corrosion product is Fe2O3. The result verifies the protection effect of the corrosion inhibitor, which can meet the anti-corrosion requirement for multi-component thermal fluid recovery.
Key words: multi-component thermal fluid, corrosion, monitor, product
Development and application of water-based wax crystal modifier type paraffin inhibitor
Song Lianyin1,Zhu Haohua2, Wang Weibo2, Wan Hua1, Zhang Qingzhu1(1.The 5th Oil Production Factory, PetroChina Changqing Oilfield Company, Xi’an 710021, Shaanxi, China; 2. Xi’an Chanqing Chemical Group Co., Ltd, Xi’an 710018, Shaanxi, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp529-533,2014（ISSN 1007-3426, IN CHINESE）
Abstract: In order to solve the disadvantages of toxic, combustible, lower density of oil-based paraffin remover, and low paraffin removal efficiency and control effect poor stability of emulsion paraffin inhibitor of water-base paraffin remover, based on the structure of hydrophilic and/or lipophilic group in surfactant, the wax crystal modifier dispersed in water homogeneously. Water-base wax crystal modifier type paraffin inhibitor has been developed. It has advantages of low toxicity, incombustible, high density, high efficiency of paraffin removal and paraffin control effect. The laboratory result showed that viscosity reduction rate and dynamic wax inhibiting rate were both more than 70％ respectively under the best proportion condition. The field result indicated that it could decrease the times of washing well and improve the production of oil well by using continuous dosing.
Key words: wax crystal modifier，wax removing/inhibiting agent，waxy production well，wax inhibition
Detailed study on volume acid fracturing technology for fractured carbonate reservoirs
He Chunming1, Cai Bo1,Tang Bangzhong2, Liu Zhe1(1. Langfang Branch of Research Institute of Petroleum E&D, Langfang 065007 Hebei, China; 2. PetroChina Huabei Oilfield Company, Renqiu 062550). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp534-538,2014（ISSN 1007-3426, IN CHINESE）
Abstract: This paper focused on the theme of how to achieve high and stable productivity for fractured carbonate reservoir.Taking the object of detailed reservoir research as the breakthrough point, through the mercury penetration experiment, NMR experiment and SEM experiment，the reservoir storage space and seepage channel were clear, and by the rock mechanics experiment, the brittleness of the reservoirs was understood. On the basis of reservoir characteristics, we put forward for the volume acid fracturing mode of “first communicate and later block, main fracture communicating, branch fracture supplement”, and with the technology of “high injecting rate, large injecting scale and the combination of high and low viscosity acid” for brittleness and fractured reservoirs, the research result has been conducted in X well of Daniudi gas field. The gas production reached 52×103 m3 /d after acid fracturing stimulation, which was more than 10 times of vertical well. The breakthrough of this well could provide a new thought for similar reservoir volume acid fracturing treatment.
Key words: fractured carbonate reservoirs, brittleness, volume acid fracturing, low damage
Preparation of P (AM-AA-AMPS) polymer microspheres by inverse emulsion polymerization
Wei Xin1, Jia Wenjun1, Cao Jing1, Zhou Ming1, He Yinglan2, Lu Ya1(1. School of Materials Science and Engineering, Southwest Petroleum University, Chengdu 610500, Sichuan, China; 2. Library of Southwest Petroleum University, Chengdu 610500,Sichuan, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp539-542,2014（ISSN 1007-3426, IN CHINESE）
Abstract: Cross-linking copolymer microspheres of P(AM-AA-AMPS) was prepared by inverse emulsion with acrylamide (AM), acrylic acid (AA), 2-acrylamide-2-methyl propane sulfonic acid (AMPS) as the monomers, Span-80 and Tween-80 as compound emulsifiers, ammonium persulfate as initiator. The structure of the microspheres was characterized by infrared spectroscopy, the morphology was studied by scanning electron microscope, particle size of microspheres was analyzed by laser particle size analyzer, and dispersibility in water of the microspheres was observed by optical microscopy.
Key words: inverse emulsion polymerization, microspheres, acrylamide, acrylic acid, 2-acrylamide-2-methyl propane sulfonic acid
Synthesis of drilling fluid loss agent KJC
Liu Dahai1, Zhang Yuan2, Duan Chunlan1,Li Huan3, Jiang Jianmin4, Chen Ting4, Kong Quan4(1. Sichuan Renzhi Oilfield Technology Services Co., Ltd, Mianyang 621000, Sichuan, China; 2. Fengcheng Operation Area, PetroChina Xinjiang Oilfield Branch Company, Karamay 834000, Xinjiang, China; 3. PetroChina Xinjiang Oilfield Branch Company, Karamay, Xinjiang 834000; 4. College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu 610500, Sichuan, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp543-546,2014（ISSN 1007-3426, IN CHINESE）
Abstract: As an important drilling fluid, the ability of heat resistance and salt tolerance of fluid loss additive directly affects the performance of water-based drilling fluid. Based on the polymer structure and functional groups, drilling fluid loss additive KJC was obtained by copolymerizing sodium styrene sulfonate (SSS), acrylamide (AM), and allyl polyethylene glycol (APEG). Taking the water loss as an evaluation index, the optimal synthesis conditions were gotten by single factor experiments, namely m(APEG)∶m(AM)∶m(SSS)=1∶2∶1, monomer mass concentration is 20%, reaction temperature is 60 ℃, initiator dosage is 0.7%, and reaction time is 5 h. The FT-IR spectrum analysis shows that the product structure is consistent with design structure synthesis. Performance evaluation shows that the synthetic polymer has good temperature resistance and the ability to resist calcium.
Key words: drilling fluid, fluid loss additive, synthesis, temperature resistance
Brief discussion on quality analysis and measurement technology of coalbed methane
Zhu Huadong1，2，Chi Yongjie1，2，Luo Qin1，2，Zhou Li1，2(1. Research Institute of Natural Gas Technology, PetroChina Southwest Oil & Gasfield Company, Chengdu 610213, Sichuan, China; 2. Key Laboratory of Natural Gas Quality and Energy Measurement, CNPC, Chengdu 610213, Sichuan, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp547-552,2014（ISSN 1007-3426, IN CHINESE）
Abstract: Coalbed methane (CBM) composition analysis in China is adopting the natural gas sampling and analysis standards at present. In this paper, the applicability of these standards for CBM was studied by theoretical evaluation and experimental verification. The results show that most of the existing methods are suitable for CBM, some methods still need to be improved for CBM quality analysis. Based on these studies, the proposals for improvement of CBM analysis methods and standardization are put forward.
Key words: coalbed methane, components analysis, sampling, H2S
Rapid determination of acid number in used aviation lubricating oil by FTIR spectrometry combined chemometrics
Wang Juxiang, Xing Zhina, Shen Gang(Department of Airborne Vehicle Engineering，Naval Aeronautical and Astronautical University，Yantai 264001, Shandong, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp553-557,2014（ISSN 1007-3426, IN CHINESE）
Abstract: The method of acid number determination in used aviation lubricating oil by fourier transform infrared (FTIR) spectrometry was studied. Infrared spectra was pretreated by S-G smoothing and the first derivative, and the respective wave number of 19 point and 17 point were selected respectively. After analyzing the spectral absorption of acid radical and comparing the spectra of new oil and used ones, wave number ranges of 3 597~3 202 cm-1 , 2 600~2 250 cm-1 and 920~800 cm-1 were selected to establish model. Calibration model was built with chemometrics methods of partial least square(PLS) and back propagation-artificial neural network(BP-ANN) respectively. Standard deviation of calibration(SEC) of PLS model was 0.004, and standard deviation of prediction (SEP) was 0.005. The accuracy of the model was validated by means of t-test(α=0.05)，and the result of t-test showed that acid number of used aviation lubricating oil could be determined quickly by FTIR spectrometry with advantages of high accuracy and no-pollution.
Key words: used aviation lubricating oil, acid number, Fourier transform infrared (FTIR), partial least squares (PLS), back propagation-artificial neural network(BP-ANN)
Sulfur content control index and determination methods of motor gasoline in China
Zhang Hanpei（Daqing Oilfield Engineering Co., Ltd., Daqing 163712, Heilongjiang, China）. CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp558-563,2014（ISSN 1007-3426, IN CHINESE）
Abstract: The paper summarized the sulfur content control index and determination methods of motor gasoline in China. The standard of motor gasoline in China has experienced five stages from the national Ⅰ level standard to the national V level standard since 1999. The national Ⅳ level standard has fully implemented and the national V level standard will be fully implemented from 2018 onwards: the sulfur content control index has been decreased from no more than 1 500 mg/kg to no more than 50 mg/kg; and the control index of no more than 10 mg/kg will be fully implemented from 2018 onwards. The conventional methods, including lamp method, ultraviolet fluorescence method, oxidative microcoulometric method, energy dispersive X-ray fluorescence spectrometry method and wavelength dispersive X-ray fluorescence spectrometry method, were described in the aspects of characteristic, determination limit, repeatability and the condition of adoption. The developmental trend of research was gas chromatography-selective detectors methods and these methods were also described.
Key words: gasoline, sulfur content, index, analytical method
Pollution reasons of injection water in Qudi Oilfield and prevention measures
Li Lei，Lei Guanglun，Wei Xiaodong，Wang Hongsheng（Institute of Petroleum Engineering, China University of Petroleum(East China), Qingdao 266580, Shandong, China）. CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp564-569,2014（ISSN 1007-3426, IN CHINESE）
Abstract: In order to solve the problem of serious water pollution along the transmission line in Shengli Qudi Oilfield, water quality changes along the line were measured. Pollution sources of injection water, pollution prevention measures and their effects were exploded. The results show that the major pollution influence factors are corrosion, iron ion, microorganism, and scaling, etc. The effective pollution prevention measures include optimization of water treatment technique, adopting effective methods to remove iron ion such as oxidation of iron removal technique and the suspended sludge filtration. Furthermore, replacement of glass tube pipe and the use of scale inhibitor HEDP (with concentration of 5-10 mg/L) will improve the water quality along the transmission line.
Key words: Qudi Oilfield, water conditioning, corrosion, scaling, pollution along transmission line
Wastewater treatment equipment in remote gas blocks of western Sichuan and its technology research
Ling Bing, Song Jia, Luo Pingkai, Qiu Linqing（Oil Field Engineering Service Branch, Sinopec Southwest Petroleum Engineering Co.,Ltd, Mianyang 621000, Sichuan, China）. CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp570-573,2014（ISSN 1007-3426, IN CHINESE）
Abstract: According to the difficulty of wastewater treatment and the high pollution indicator of wastewater from gas production in remote gas blocks, of western Sichuan, a set of wastewater treatment equipment is developed. The device contains 11 units, mainly using four kinds of advanced technologies, such as electro-coagulation air floatation technique, inclined tube sedimentation process, sieve tray absorption-O3/H2O2 complex oxidation process, and filter-ozone composite process. After field contrast test, the optimum operating parameters of the device are determined, which the electrical air floatation current is about 3 500 A, the processing flow is about 8 m3/h, the pH value of effluent from the first order sedimentation tank is 13 or so, the dosage of hydrogen peroxide is around 7 g/min, and the ozone dosage is about 96 g/min. The field wastewater test result shows that the equipment has a good effect in removal of oil, suspended solids and COD of wastewater in remote gas blocks of western Sichuan, and the water quality reaches the primary level of the Integrated Wastewater Discharge Standard (GB 8978－1996), which provides a convenient and practical device for the field standard treatment with wastewater in the field.
Key words: wastewater in gas field, remote blocks, field treatment equipment, technology, experiment
Security analysis and measures for the liquefaction process of oxygen-bearing coal-bed methane
Deng Ji, Zhu Lin, Xiao Ya, Zhao Qilong(College of Chemistry and Chemical Engineering，Southwest Petroleum University, Chengdu 610500, Sichuan, China). CHEMICAL ENGINEERING OF OIL & GAS, VOL.43, NO.5,pp574-578,2014（ISSN 1007-3426, IN CHINESE）
Abstract: There is a risk of explosion during purifying the coal-bed methane coming from underground drainage, for the reason that the gas contains oxygen. In this paper, the results of simulation with HYSYS and the flammability limit theory were combined together to analyze the security of whole process. The results showed that the explosion hazard concentrated at the end of the condensation and on the top of rectification tower. The measure to reduce the compressor outlet pressure or raise the final condensation temperature was proposed. What′s more, the security measure was proposed to control the methane content of rectification tower gas above the upper limit of the explosion strictly, and then the inerting gas with nitrogen contacts with liquid nitrogen upstream for further recovery of CH4. The results indicate that when the value of nitrogen injection ratio is greater than 0.6 (mole ratio)，there is no danger of explosion in liquefaction process, and both methane yield and process safety are improved greatly in this way.
Key words: oxygen-bearing coal-bed methane, liquefaction, simulation, flammability limits, inerting
