Sun B.,Gansu Boiler and Pressure Vessel Inspection and Research Center Lanzhou |
Wu J.,Gansu Boiler and Pressure Vessel Inspection and Research Center Lanzhou |
Li L.,CPECC East China Design Branch |
Xinan Shiyou Daxue Xuebao/Journal of Southwest Petroleum University | Year: 2013
The remaining strength of the in-service corroded oil and gas pipeline was predicted based on artificial neural network's ability to approximate complex function. But artificial neural network has drawbacks as follows: the initial distribution of weight and threshold value is a stochastic process and it was the local optimization algorithm, and that the local minimum solution tends to appear in the convergence process. Therefore, the weight and threshold value of BP neural network using L-M algorithm were optimized based on the global search ability and independence of the gradient information of genetic algorithm, and with consideration of the influencing factors of failure pressure of oil and gas pipeline determined by sensitivity analysis, the GA-BP(L-M) network model was built. The network was trained using sample of Modified ASME B31G and predictions were made. The results show that the GA-BP(L-M) network model can better predict failure pressure of oil and gas pipeline, which proves to be a more scientific and accurate model.
Li H.W.,Qingdao Technological University |
Li Y.J.,CPECC East China Design Branch |
Wu W.,Staffordshire University |
Lu M.,Qingdao Technological University
Procedia Environmental Sciences | Year: 2011
Based on the characteristics of urban water supply system, the urban pipe network security assessment system was established, and then AHP method combined with fuzzy evaluation was used to carry out a comprehensive security assessment for the leakage of the urban pipe network. By calculating a real case and analyzing various leakage causes and their impact, the assessment model was verified reasonable. © 2011 Published by Elsevier Ltd.
Yu S.,China University of Petroleum - East China |
Yu S.,Petrochina |
Zhang J.,CPECC East China Design Branch |
Cheng T.,Petrochina |
And 3 more authors.
China Petroleum Processing and Petrochemical Technology | Year: 2012
Different amounts of FCC slurry oil and HVGO were added to Tahe atmospheric residue respectively. The colloidal stability and asphaltene agglomeration of atmospheric residue and mixed oils were characterized by means of the mass fraction normalized conductivity and the small-angle X-ray scattering technology (SAXS). The results indicated that the stability of Tahe atmospheric residue decreased with an increasing amount of these oil fractions. It was found that the decline of the colloidal stability was attributed to the component polarity difference between oil fractions and the atmospheric residue. Though the aromaticity of FCC slurry oil was higher than that of HVGO, the polarity of aromatics and resins of FCC slurry oil was lower than those of HVGO. So the degree of the colloidal stability was more seriously destroyed by FCC slurry oil. The dispersion of asphaltenes in Tahe atmospheric residue was changed by adding FCC slurry oil and HVGO. The particle size of asphaltenes increased along with the decline of the colloidal stability.
Yu W.,Petrochina |
Sen D.,Petrochina |
Keqian X.,CPECC East China Design Branch |
Yanping L.,CPECC East China Design Branch
Petroleum Refinery Engineering | Year: 2015
The catalyst cooler tubes of the 1.4 MM TPY RFCC unit in PetroChina Dalian Petrochemical Company ruptured many times and the catalyst particles depositions were difficult to be removed, which have seriously affected the safe operation of the unit at full capacity. The unit was revamped with intensified coke- burning process, catalyst fluidization and transfer process and catalyst cooler process for heat removal, etc. After revamping, the full regeneration of 1 st-stage and 2nd-stage regenerator was realized, and high-temperature heat removal furnace was removed. The results showed 1 ) that the problems of rupture of high-temperature heat removal furnace tubes, high CO in flue gas and the plugging of air riser from 1 st-stage reactor to 2 nd- stage reactor were solved; 2) The low-temperature high -efficiency regeneration of catalyst were realized, CO in regenerator flue gas was 0 ∼ 150 mg/m3 and NO, was 100 ∼ 180 mg/m3, the catalyst to oil ratio in the reactor and heavy oil reaction conditions were effectively improved, and the total liquid yield was increased by about 1% at the 6.0% and 6.4% carbon residue of feedstock. The main equipment and supports in the reactor and regenerator system were substantially maintained, which has saved investment. The unit has been running stably after revamping, and the safety, environmental protection and product yields have been improved.
Liu W.,CPECC East China Design Branch |
Yuan M.,CPECC East China Design Branch |
Petroleum Refinery Engineering | Year: 2013
The FCC unit, which is characterized by wide-range feedstocks, high heavy oil conversion, low operating pressure and low capital investment, is the main downstream process unit in contemporary oil refineries for producing motor fuel and light olefins. The product slates can be flexibly adjusted. With the crude oil becoming increasingly heavier and environmental regulations increasingly stricter, the FCC units are confronted with a number of problems, such as FCC gasoline and diesel having to be hydrotreated, low octane number of diesel, and limitation of flue gas emissions. The optimal integration of FCC unit with various hydrotreating units can bring the role of FCC unit into a full play. The characteristics and development orientation of grass-roots FCC units and revamped FCC units in recent years are introduced.
Liang X.,Xi'an University of Architecture and Technology |
Kang L.,CPECC East China Design Branch |
Deng M.,Xi'an University of Architecture and Technology |
Dang Z.,Xi'an University of Architecture and Technology
Jianzhu Jiegou Xuebao/Journal of Building Structures | Year: 2014
In order to improve the seismic behavior of the reinforced concrete column, the fiber-reinforced concrete (FRC) was applied in the potential plastic region of the column instead of ordinary concrete. A series of six reinforced concrete column specimens with shear span ratio of 3 and little stirrup were designed, where five specimens were made of FRC in the potential plastic region, and one was conventional concrete column for comparison. By means of quasi-static tests, the cracking and damage process of the specimens were studied under low cyclic reversed lateral loads. The hysteretic behavior, deformability and energy dissipation capacity were analyzed for various FRC region, axial load ratio and concrete strength. The results show that, combined with normal concrete columns, the column with FRC in the potential plastic region and little stirrup exhibits shear failures after the longitudinal reinforcement yielding with better ductile characteristics and damage tolerance. As the height of FRC region doubled, the displacement ductility ratio and drift ratio increased by 45% and 21% respectively, and energy dissipation capacity increased by 81%. The column with FRC in the part of column can reduce the amounts of confining reinforcements and shear stirrups.
Xueyun L.,CPECC East China Design Branch
Petroleum Refinery Engineering | Year: 2014
The FCC gasoline in the gasoline pool in China was over 70%. With the adjustment of configurations of the petroleum refineries and construction and operation of mego refineries in recent years, the percentage of FCC processing capacity is lowered to 28.4% while the CCR processing capacity is increased to 9.5%. Whereas, there is still a great gap with the developed countries. The FCC gasoline, which is high in sulfur and blending percentage, has a great impact on the quality of motor gasoline in China. The gasoline compositions of gasoline pools as well as well as refinery process unit configurations both in China and abroad are studied, and two different gasoline desulfurization processes are compared. It is recommended to adjust the existing process unit configurations to reduce the FCC gasoline percentage in the gasoline pool. The selection of state-of-art after-treatment processes is recommended to remove the sulfur from FCC gasoline to improve the quality of motor gasoline.
Liu N.,CPECC East China Design Branch |
Zhang L.,CPECC East China Design Branch |
Zhang X.,CPECC East China Design Branch
Petroleum Refinery Engineering | Year: 2013
In an overseas refinery where MTBE is forbidden to be blended into gasoline and some gasoline specifications are more stringent than Euro-V specifications in target market, the gasoline octane number, aromatics and RVP are off-specifications. Therefore, the clean blending components of high octane and low RVP are required to improve the gasoline quality, and alkylate is a satisfactoiy selection based upon experience. The study by the designers has found that the operation of a large alkylation unit can improve the gasoline quality. As the MTBE is forbidden in the project and MTBE is in surplus supply an integration process of normal butane isomerization and alkylation is recommended to increase the production of high-octane alkylate. The mixed C 4s and unreacted normal butanes from alkylation unit are sent to isomerization unit for treatment to increase the iso-butane production so as to raise the paraffin to olefin ratio. The implementation of this process has greatly improved the product gasoline quality. The octane number of gasoline is increased by 0. 59, aromatic content is decreased by 7.23% and vapor pressure is lowered by 1.86 kPa.
Li H.-B.,CPECC East China Design Branch
Petrochemical Equipment | Year: 2013
In the design and calculate process of large diameter overlap-floating heat exchanger, generally, the anchor bolts stress could not approved because of its too much seismic forces. So the saddle support needs to adjust properly, while, increase the diameter of anchor bolt or changed materials and so on, which is the most convenient selection. The calculation process of adjustment and the scheme of saddle support's checking calculation were introduced. And by using of the software PV Desktop flexibly to do the analysis-adjustment-reanalysis calculation checking process to example, the reasonable solution is given.
Fan Z.-L.,CPECC East China Design Branch |
Liu D.-F.,CPECC East China Design Branch |
Zhang X.,CPECC East China Design Branch
Xiandai Huagong/Modern Chemical Industry | Year: 2014
The allowable temperature difference at the pinch point is reduced by using plate heat exchangers in CDU&VDU heat exchanger network, which is helpful to improve the heat recovery and reduce the total cost. The problem involving the increased heat exchanger area and capital cost by decreasing the minimum temperature difference, is solved via optimization of the design of heat exchanger network. This method is used in one CDU&VDU project. The final temperature is improved, and the consumption of fuel and recycled water is reduced. The economic benefit is significant in practice.