Route Optimization of Pipeline in Gas-Liquid Two-Phase Flow Based on Genetic Algorithm

This paper describes the problems in route optimization of two-phase pipelines. Combining the hydraulic calculation with route optimization theory, this paper establishes an automatic route optimization model and adopts the general genetic algorithm (gGA) and steady-state genetic algorithm (ssGA) to solve the model, respectively, gets the optimal route, and discusses the influence of parameters setting to the result. This algorithm was applied in determining pipelines routes in coalbed methane gathering and transporting system in Shanxi Province, China. The result shows that the algorithm is feasible, which improves the hydraulic properties by reducing the pressure drop along the line while the pipeline length is still acceptable

Standardized surface engineering design of shale gas reservoirs

Due to the special physical properties of shale gas reservoirs, it is necessary to adopt unconventional and standardized technologies for its surface engineering construction. In addition, the surface engineering design of shale gas reservoirs in China faces many difficulties, such as high uncertainty of the gathering and transportation scale, poor adaptability of pipe network and station layout, difficult matching of the process equipments, and boosting production at the late stage. In view of these problems, the surface engineering construction of shale gas reservoirs should follow the principles of “standardized design, modularized construction and skid mounted equipment”. In this paper, standardized surface engineering design technologies for shale gas reservoirs were developed with the “standardized well station layout, universal process, modular function zoning, skid mounted equipment selection, intensive site design, digitized production management” as the core, after literature analysis and technology exploration were carried out. Then its application background and surface technology route were discussed with a typical shale gas field in Sichuan–Chongqing area as an example. Its surface gathering system was designed in a standardized way, including standardized process, the modularized gathering and transportation station, serialized dehydration unit and intensive layout, and remarkable effects were achieved. A flexible, practical and reliable ground production system was built, and a series of standardized technology and modularized design were completed, including cluster well platform, set station, supporting projects. In this way, a system applicable to domestic shale gas surface engineering construction is developed

Route Optimization of Pipeline in Gas-Liquid Two-Phase Flow Based on Genetic Algorithm

This paper describes the problems in route optimization of two-phase pipelines. Combining the hydraulic calculation with route optimization theory, this paper establishes an automatic route optimization model and adopts the general genetic algorithm (gGA) and steady-state genetic algorithm (ssGA) to solve the model, respectively, gets the optimal route, and discusses the influence of parameters setting to the result. This algorithm was applied in determining pipelines routes in coalbed methane gathering and transporting system in Shanxi Province, China. The result shows that the algorithm is feasible, which improves the hydraulic properties by reducing the pressure drop along the line while the pipeline length is still acceptable

Coalbed Methane Production System Simulation and Deliverability Forecasting: Coupled Surface Network/Wellbore/Reservoir Calculation

As an unconventional energy, coalbed methane (CBM) mainly exists in coal bed with adsorption, whose productivity is different from conventional gas reservoir. This paper explains the wellbore pressure drop, surface pipeline network simulation, and reservoir calculation model of CBM. A coupled surface/wellbore/reservoir calculation architecture was presented, to coordinate the gas production in each calculation period until the balance of surface/wellbore/reservoir. This coupled calculation method was applied to a CBM field for predicting production. The daily gas production increased year by year at the first time and then decreased gradually after several years, while the daily water production was reduced all the time with the successive decline of the formation pressure. The production of gas and water in each well is almost the same when the structure is a star. When system structure is a dendritic surface system, the daily gas production ranked highest at the well which is the nearest to the surface system collection point and lowest at the well which is the farthest to the surface system collection point. This coupled calculation method could be used to predict the water production, gas production, and formation pressure of a CBM field during a period of time

Brain Radiotherapy Combined with Sequential Chemotherapy in Non-Small-Cell Lung Cancer Patients with Brain Metastases

Background and objective Brain irradiation is the traditional treatment for NSCLC patients with brain metastases, whereas combined with chemotherapy is the nowadays treatment direction. Since sequential/maintenance chemotherapy has shown promising results in advanced NSCLC, we carried out the study to explore the role of sequential chemotherapy combined with brain radiotherapy in patients with brain metastases. Methods Treatment naïve NSCLC patients with brain metastases sequentially received the 3 chemotherapy regimens TP-NP-GP. The TP regimen consisted of Paclitaxol 175 mg/m2 d1, Cisplatin 20 mg/m2 d1-5. The NP regimen consisted of Nevalbine 25 mg/m2 d1 and 8, Cisplatin 20 mg/m2 d1-5. The GP regimen consisted of Gemcitabine 1 g/m2 d1 and 8, Cisplatin 20 mg/m2 d1-5. All regimens were repeated every 3 weeks. Each regimen was executed for at least 2 cycles and no more than 4 cycles. Results The response rates of TP, NP and GP sequentially used were 41.2%, 35.6% and 27.8% respectively for the out brain lesions and 60.8% for the brain lesions combining with brain irradiation. Median survival time was 14.7 months and the 1, 2 and 3 year overall survivals were 67.8%, 20.6% and 1.3% respectively. Conclusion The 3rd generation regimen-based sequential chemotherapy combined with WBRT was effective for NSCLC patients with brain metastasis with an encouraging survival and acceptable tolerability

Effect of Conductive Material Morphology on Spherical Lithium Iron Phosphate

As an integral part of a lithium-ion battery, carbonaceous conductive agents have an important impact on the performance of the battery. Carbon sources (e.g., granular Super-P and KS-15, linear carbon nanotube, layered graphene) with different morphologies were added into the battery as conductive agents, and the effects of their morphologies on the electrochemical performance and processability of spherical lithium iron phosphate were investigated. The results show that the linear carbon nanotube and layered graphene enable conductive agents to efficiently connect to the cathode materials, which contribute to improving the stability of the electrode-slurry and reducing the internal resistance of cells. The batteries using nanotubes and graphene as conductive agents showed weaker battery internal resistance, excellent electrochemical performance and low-temperature dischargeability. The battery using carbon nanotube as the conductive agent had the best overall performance with an internal resistance of 30 mΩ. The battery using a carbon nanotube as the conductive agent exhibited better low-temperature performance, whose discharge capacity at −20 °C can reach 343 mAh, corresponding to 65.0% of that at 25 °C

A facile synthesis of nitrogen-doped hierarchical porous carbon with hollow sphere structure for high-performance supercapacitors

In this work, nitrogen-doped carbon with hierarchical porous and hollow sphere structure has been synthesized through a simple and facile route of spray drying using glycine as the nitrogen-containing carbon source. After KOH activation, the prepared material (NHPCA) shows a large specific surface area of 962m(2)g(-1) with moderate N-doping of 5.74% and exhibits a high specific capacitance of 271Fg(-1) in 6M KOH electrolyte at 1.0Ag(-1), remarkable rate capability and particularly stable cycling performance with no significant specific capacitance drop after 10000 cycles at 1.0Ag(-1). The excellent electrochemical properties come from the unique structure and the doping of nitrogen. The hierarchical pore structure improves the efficiency of electrolyte ions transport, and diffusion and the hollow sphere structure further facilitates mass transport. The doping of nitrogen increases the total capacitance by providing redox pseudo-capacitance. The results indicate the as-prepared nitrogen-doped carbon with hierarchical porous and hollow sphere structure can be used as a hopeful candidate for an efficient electrode of commercial supercapacitors devices.</p