Artificial lift infrastructure planning of shale gas horizontal wells considering endogenous and exogenous uncertainties

Artificial lift methods (ALMs) lift the accumulated fluids from horizontal shale-gas-producing wells and help sustain well performance. An artificial lift infrastructure plan includes the selection of ALMs and their operating schedule. This paper presents two discrete-time large-scale nonconvex mixed-integer nonlinear programming models to solve the artificial lift infrastructure planning problem. Two equivalent mixed-integer linear programming models are formulated using the special structure of the nonlinear terms. A set of valid inequalities is defined to tighten the models and shorten solution times to two orders of magnitude, considering well production limitations. We incorporate endogenous uncertainty in ALM-dependent production rates and exogenous uncertainty in shale gas prices into the models. For a hypothetical case study under only endogenous uncertainties, the value of the stochastic solution is 5%. For the same case study, the exogenous uncertainty in gas prices does not change the optimum solution.     

连续气举采油最大产量的优化计算法

根据节点系统分析原理和最优多相流相关式,讨论了利用计算机对连续气举采油时的最大产量进行优化运算的方法,得到了满意的结果。     

Role of inertial lift in elutriating particles according to their density

A Reflux Classifier involves the liquid fluidization of particles into a set of parallel inclined channels. Closely spaced inclined channels promote a combination of laminar flow and a high shear rate, which in turn promote the elutriation of the particles according to their density. The hydrodynamics of the particle transport within the inclined channels was examined theoretically by combining established equations for describing the fluid flow, the terminal velocity of a particle, and the shear induced inertial lift, with no adjustable parameters. The theoretical calculations provided excellent agreement with a comprehensive experimental data set, demonstrating the significance of the inertial lift force that arises at a high shear rate under the condition of laminar flow. Complex features of the experimental data were described theoretically. This work explains how it is possible to elutriate particles according to their density, with the effects of particle size suppressed. A remarkable convergence of several criteria was found to be necessary for achieving the reported phenomena.     

纵缝焊接升降平台的开发及利用

介绍了一种解决筒体埋弧自动焊接工作的纵逢升降平台,它可实现流水作业,降低了成本,提高了工效。     

硝基苯二次水恒压供水系统的改造

从硝基苯供水系统的基本模型及工作特性入手，论述了变频器调速供水的原理及优点，介绍了用变频调速系统实现恒压供水控制的方法。     

水质波动下的离子交换除盐

结合铜化集团华兴化工有限公司离子交换法除盐水系统运行经验,对水质波动下的离子交换除盐运行周期及再生进行了研究和探索,准确判断交换器的运行周期以确保出水水质合格。采用再生控制器控制再生过程,再生效果稳定,酸、碱消耗分别比优化前降低20%和30%。     

The Impact of Intermittent Aeration on the Operation of Air‐Lift Tubular Membrane Bioreactors under Sub‐Critical Conditions

Abstract

An air‐lift sidestream polymeric multi‐tube membrane module has been investigated to compare the hydraulic performance of an MBR challenged with municipal wastewater and landfill leachate. In both cases the MBRs were operated under the same conditions of membrane aeration rate and sludge retention time, but with hydraulic retention time for the leachate set by scoping trials based on porous pots to 48 hours. Operation under conventional continuous aeration conditions yielded critical flux values, based on classical flux step experiments, of 36–42 l m^?2 hr^?1 for the sewage‐fed trial compared with ～24 l m^?2 hr^?1 for the leachate‐fed trial. Substantial improvements in operating flux, between 20 and 100%, were obtained when operating with air pulsing (1s on/s off). Intermittent operation under more conventional conditions (5s on/5s off) yielded no improvement.     

二氧化碳压缩机提板阀波动原因探讨与对策

1概述 大庆石化公司化肥厂尿素装置二氧化碳压缩机控制机构经改造后,采用3+系列防喘振控制系统,速度控制部分主要由3+系列的速度控制器(SIC112)、抽气控制器(PIC920)、注气控制器(PIC901)及油路环节(包括油系统过滤器、分油器、电液转换器、油动机等)所构成.控制器SIC112、PIC920、PIC901输出4～20mA电流信号,完成常规PID控制;油路环节实现电液信号转换,最终驱动3个提板阀V1、V2、V3动作,达到对转速的控制.控制系统构成如图1所示.     

气升式反应器内三相条件下流动行为研究Ⅱ——循环液速的影响

在一个体积为8L（直径96mm,高为1800mm）带导流筒的气升式反应器内,模拟两相（空气-水,空气-水-乙醇）系统和三相（空气-水-玻璃珠,空气-水-乙醇-淀粉）系统,改变给气流量,导流管直径,乙醇浓度,玻璃珠直径,固含率,淀粉含量,系统温度,以及操作方式考察了以上因素对气升式反应器内循环液速的影响。研究表明：随着上升气体表观速度的增加,导流简直径的增加,床内循环液速也增加;在固含率一定条件下,固含物粒径烊大,循环液速也越大;溶液浓度增加,循环液速也增加;床层中的固含率增加,而循环液速减小;系统温度增加,循环液速增加;环隙给气方式可以与中心导流简给气方式都可采用,但是环隙给气时怕循环液速小于中心导流筒给气方式的循环液速。     

Limiting flux in microfiltration of colloidal suspensions by focusing on hydrodynamic forces in viscous sublayer

Cross‐flow microfiltration tests were performed on colloidal suspensions under turbulence conditions. By changing the particle diameter, flow rate, and channel height in the membrane housing to measure limiting fluxes, the influence of each parameter on the limiting flux was assessed from the viewpoint of hydrodynamic forces exerted on a particle in the viscous sublayer. In analyzing all the data taken, the particle Reynolds number calculated from the limiting flux is proportional to the 1.5 power of that calculated from the flow rate at the boundary between the viscous sublayer and the intermediate layer. This fact indicates that the limiting flux can be determined in situations where the drag force exerted by the flux is balanced by the lift force in the viscous sublayer. © 2017 American Institute of Chemical Engineers AIChE J, 64: 1760–1765, 2018