Research on a TOPSIS energy efficiency evaluation system for crude oil gathering and transportation systems based on a GA-BP neural network

As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex structures.It is necessary to establish an energy efficiency evaluation system for crude oil gathering and transportation systems and identify the energy efficiency gaps.In this paper,the energy efficiency evaluation system of the crude oil gathering and transportation system in an oilfield in western China is established.Combined with the big data analysis method,the GA-BP neural network is used to establish the energy efficiency index prediction model for crude oil gathering and transportation systems.The comprehensive energy consumption,gas consumption,power consumption,energy utilization rate,heat utilization rate,and power utilization rate of crude oil gathering and transportation systems are predicted.Considering the efficiency and unit consumption index of the crude oil gathering and transportation system,the energy efficiency evaluation system of the crude oil gathering and transportation system is established based on a game theory combined weighting method and TOPSIS evaluation method,and the subjective weight is determined by the triangular fuzzy analytic hierarchy process.The entropy weight method determines the objective weight,and the combined weight of game theory combines subjectivity with objectivity to comprehensively evaluate the comprehensive energy efficiency of crude oil gathering and transportation systems and their subsystems.Finally,the weak links in energy utilization are identified,and energy conservation and consumption reduction are improved.The above research provides technical support for the green,efficient and intelligent development of crude oil gathering and transportation systems.

Shortcut Method of Design and Energy-Saving Analysis of Sargent Dividing Wall Column

The Sargent dividing wall column can implement four products separation sequences in one column based on Fully Thermally Coupled Distillation Column. The initial design parameters are required for the design optimization or dynamic control of the Sargent dividing wall column, and in order to make the rigorous simulation of the Sargent dividing wall column more conducive to convergence, a ten column model for complex Sargent column is established in this paper,and the shortcut design method of this model is proposed. The internal minimum vapor and liquid flow are obtained by the Underwood equations and the mass balance method and the V-min method. The separation for a 4-component shortcut mixture of pentane, hexane, heptane and octane was considered, while the initial values of design parameters and the ratio of vapor-liquid distribution of each column were calculated by using the shortcut design method of a ten column model. And by comparing the shortcut calculations with rigorous simulation results, the practicality and reliability of shortcut calculations were verified. The reason for energy saving was analyzed based on back-mixing. A virtual heat exchanger is proposed to make the Sargent dividing wall column more energy efficient.

Mechanism analysis of solvent selectivity and energy-saving optimization in vapor recompression-assisted extractive distillation for separation of binary azeotrope

Octane and p-xylene are common components in crude gasoline,so their separation process is very important in petroleum industry.The azeotrope and near azeotrope are often separated by extractive distillation in industry,which can realize the recovery and utilization of resources.In this work,the vapor–liquid equilibrium experiment was used to obtain the vapor–liquid equilibrium properties of the difficult separation system,and on this basis,the solvent extraction mechanism was studied.The mechanism of solvent separation plays a guiding role in selecting suitable solvents for industrial separation.The interaction energy,bond length and charge density distribution of p-xylene with solvent are calculated by quantum chemistry method.The quantum chemistry calculation results and experiment results showed that N-formylmorpholine is the best solvent among the alternative solvents in the work.This work provides an effective and complete solvent screening process from phase equilibrium experiments to quantum chemical calculation.An extractive distillation simulation process with N-formylmorpholine as solvent is designed to separate octane and p-xylene.In addition,the feasibility and effectiveness of the intensified vapor recompression assisted extraction distillation are also discussed.In the extractive distillation process,the vapor recompression-assisted extraction distillation process is globally optimal.Compared with basic process,the total annual cost can be reduced by 43.2%.This study provides theoretical guidance for extractive distillation separation technology and solvent selection.

Energy-saving potential analysis for teaching building with intermittent heating system in university of Tianjin

An energy consumption analysis based on the heating characteristic of a building with central heat exchanger in a university of Tianjin was done,and the feasibility of intermittent heating with variable speed pumps was discussed. By comparing various methods of energy consumption analysis,a modified Bin method based on the weather data in Tianjin was adopted. The heat consumption of the buildings under intermittent heating mode was calculated and compared with continuous heating mode,the result shows that intermittent heating can reduce energy consumption for 1 941 759 kW·h,save standard coal for 341 t,and reduce pump power consumption for 72 679 kW·h annually. Intermittent operation by means of varying the pump frequency not only leads to savings in fuel consumption and reduction in pollutant emissions,but also reduces operating costs significantly and it is an ideal energy-saving method. By analyzing the results,the recommendations of heating operation regulation and the transformation of pipe network were proposed separately to different kinds of buildings in colleges,such as laboratory building,teaching building.

Electric Energy Saving

Over all fuel condition and the money we spend on the said fuel leads us to think about savings. What can we do？ As individuals, we can educate our students and their family members. The easiest way to do that is to monitor their weekly spending for them. Together with their family members, the students have to monitor the consumption of electrical energy through three weeks. In the first week, they should spend electricity as they do everyday. During the second week they have the increase of spending of electrical energy. The third week is the saving energy week. They have to make a plan with their family members on how to save energy, for example, turning offthe lights in the empty rooms, turning offthe TV when there is no one watching it, etc.. Every week they have to note the data in kilowatts. When they acquire all the information and transform it into money they can see if it＇s worth saving electrical energy or not. They will see they don＇t have to give up the comforts of the modern life. The value of the project is in the fact that many households continue with the electrical energy saving. In fact, the number of the households is increasing.

Application Analysis of Energy Saving Measures in Oilfield Electrical Engineering

With the rapid development of the social economy,people are paying more and more attention to environmental issues.If society wants sustainable development,it must put energy conservation and emission reduction on the agenda.At this stage,China has vigorously promoted energy conservation and emission reduction,and all walks of life have gradually embarked on the green road of energy conservation.In recent years,energy saving measures has been widely used in China's oilfield electrical engineering.The author explores and analyzes the basic principles of energy saving measures applied in oilfield electrical engineering,and proposes an effective way to apply energy saving measures in oilfield electrical engineering,hoping to contribute to the energy saving effect of oilfield electrical engineering.

Simulation of District Cooling Plant and Efficient Energy Air Cooled Condensers (Part I)

In hot arid countries with severe weather, the summer air conditioning systems consume much electrical power at peak period. Shifting the loads peak to off-peak period with thermal storage is recommended. Model A of residential buildings and Model B of schools and hospitals were used to estimate the daily cooling load profile in Makkah, Saudi Arabia at latitude of 21.42°N and longitude of 39.83°E. Model A was constructed from common materials, but Model B as Model A with 5 - 8 cm thermal insulation and double layers glass windows. The average data of Makkah weather through 2010, 2011 and 2012 were used to calculate the cooling load profile and performance of air conditioning systems. The maximum cooling load was calculated at 15:00 o’clock for a main floor building to a 40-floor of residential building and to 5 floors of schools. A district cooling plant of 180,000 Refrigeration Ton was suggested to serve the Gabal Al Sharashf area in the central zone of Makkah. A thermal storage system to store the excess cooling capacity was used. Air cooled condensers were used in the analysis of chiller refrigeration cycle. The operating cost was mainly a function of electrical energy consumption. Fixed electricity tariff was 0.04 $/kWh for electromechanical counter, and 0.027, 0.04, 0.069 $/kWh for shifting loads peak for the smart digital counter. The results showed that the daily savings in consumed power are 8.27% in spring, 6.86% in summer, 8.81% in autumn, and 14.55% in winter. Also, the daily savings in electricity bills are 12.26% in spring, 16.66% in summer, 12.84% in autumn, and 14.55% in winter. The obtained maximum saving in consumed power is 14.5% and the daily saving in electricity bills is 43% in summer when the loads peak is completely shifted to off-peak period.

Data Prediction in Distributed Sensor Networks Using Adam Bashforth Moulton Method

Information collection from remote location is very important for several tasks such as temperate monitoring, air quality investigation, and wartime surveillance. Wireless sensor network is the first choice to complete these types of tasks. Basically, information prediction scheme is an important feature in any sensor nodes. The efficiency of the sensor network can be improved to large extent with a suitable information prediction scheme. Previously, there were several efforts to resolve this problem, but their accuracy is decreased as the prediction threshold reduces to a small value. Our proposed Adams-Bashforth-Moulton algorithm to overcome this drawback was compared with the Milne Simpson scheme. The proposed algorithm is simulated on distributed sensor nodes where information is gathered from the Intel Berkeley Research Laboratory. To maximize the power saving in wireless sensor network, our adopted method achieves the accuracy of 60.28 and 59.2238 for prediction threshold of 0.01 for Milne Simpson and Adams-Bashforth-Moulton algorithms, respectively.

Electricity Pricing for Natural Gas CHP Projects The Higher, the Better?

Regarding the state's policy that gives a higher on-grid electricity price to natural gas CHP (combined heat and power) projects, this paper studies the effect of it on the operation of those projects by theoretical analysis and a case study. It concludes that on-grid electricity price on the high side, compared to heat price, will lead power plants to produce more electricity but less heat, thus causing decrease of the plants' thermal eff iciency and harm to energy saving of the whole society.

Experimental Study on the Thermal Performances of a Tube-Type Indirect Evaporative Cooler

The so-called indirect evaporative cooling technology is widely used in air conditioning applications.The thermal characterization of tube-type indirect evaporative coolers,however,still presents challenges which need to be addressed to make this technology more reliable and easy to implement.This experimental study deals with the performances of a tube-type indirect evaporative cooler based on an aluminum tube with a 10 mm diameter.In particular,the required tests were carried out considering a range of dry-bulb temperatures between 16℃ and 18℃ and a temperature difference between the wet-bulb and dry-bulb temperature of 2℃∼4℃.The integrated convective heat transfer coefficient inside the tube in the drenching condition has been found to lie in the range between 36.10 and 437.4(W/(m^(2)⋅K)).

电动装载机转向系统电液流量匹配控制策略

针对电动装载机优先型流量放大转向系统单动工况下节流损耗严重的问题,提出了一种电液流量自适应匹配的节能型控制策略。首先,介绍了优先型流量放大转向系统工作原理;其次,建立转向系统能量损失模型;然后,提出转向系统电液流量匹配控制策略,实现液压泵输出流量与转向系统需求流量的匹配,并构建液压泵流量非线性映射补偿模型,提升流量控制精度;最后,利用AMESim软件搭建系统仿真模型,与原系统对比仿真分析。结果表明:改进后系统流量损耗降低62.68%,能量损耗减少65.26%,节能效果显著,为电动装载机的推广应用奠定基础。

基于规则的信号交叉口纯电动公交节能驾驶策略

为解决纯电动公交在通过信号交叉口时能耗较大的问题,本文提出一种旨在最小化电量消耗的基于规则的两阶段驾驶策略,能够实现通行策略场景的合理划分选择及充分优化加减速调整曲线凹凸性,同时,不牺牲乘客舒适度和通行时间。在策略第1阶段,结合车辆运行状态和通过车路协同技术获取的交叉口信号相位和时序信息,提出4种交叉口通行策略的划分与判断选择方式,包括匀速通过策略、加速通过策略、减速通过策略和制动停车策略;在策略第2阶段,利用基于XGBoost算法的能耗估算模型和基于加减速特征参数的曲线模型,优化策略场景中匀速过程、加速过程和减速过程的速度曲线;最后,结合VISSIM仿真验证4种通行策略的有效性。结果表明,所提出的策略可以有效减少电量消耗,在4种驾驶场景下,降低了29.8%~34.2%的能耗。此外,分析发现,在经济车速以上和以下的最佳速度节能曲线均为凹凸形曲线,因此,通过对比实验进行不同速度调整范围的最节能曲线凹凸性规律总结,该结论可以为纯电动公交车的节能驾驶提供更易于操作的驾驶引导。

基于CFD的某远洋围网渔船纵倾节能技术

为响应联合国粮农组织(FAO)提出的“蓝色倡议”和海洋经济可持续发展要求,降低某40 m远洋围网渔船整个营运周期的能耗和运营成本,提高远洋渔船的能效管理技术水平,本研究依托渔船数字化研发平台,基于雷诺平均方程法(RANS),运用计算流体力学(CFD)分析软件STAR-CCM+对该远洋围网渔船不同吃水、不同纵倾状态下的船舶阻力进行仿真计算,分析其阻力的变化规律并寻找不同吃水不同航速下的最佳纵倾角度,针对围网渔船完整营运周期中关键工况点的排水量和航速需求,建立全工况最佳纵倾操作手册和主机功率的经济性选择方案,并通过船舶正浮状态和最佳纵倾状态能耗对比计算验证纵倾优化的实际节能效果。研究结果可为同类型远洋渔船的节能减排优化设计和运营管理提供案例参考。

贵州高速公路基于无极调光的隧道照明能耗测算

高速公路隧道照明在不同管控策略下能耗差异较大,当前无极调光模式下动态变化因素较多,导致测算照明能耗比较困难。为量化研究公路隧道运营过程中采用智能无极调光控制系统时的能耗水平,提出了一种基于季节、历史天气和实时洞外亮度的能耗计算模型。首先分析了公路隧道照明设计现状与不同天气工况下的调光控制策略,为公路隧道照明的能耗计算提供理论支撑;其次构建了基于季节、历史天气预测和单日实时洞外亮度变化的能耗计算模型,并以贵州省在建小寨隧道为例测算了能耗情况。结果表明,基于季节、历史天气统计与洞外亮度等因素测算的能耗能更加真实有效反映智能无极调光系统的实际运营状况,为运营管理单位实时调整照明控制策略与节能升级改造提供重要的参考依据。

基于双通道多特征融合的发电设备绿色节能控制方法研究

以往的发电设备绿色节能控制方法由于仅提取发电设备运行状态的功率特征,导致方法的控制效果较差。因此,设计了基于双通道多特征融合的发电设备绿色节能控制方法。首先,分析双通道多特征融合基本原理,利用传感器获取大量发电设备运行状态数据,并对数据进行优化处理,以分析发电设备运行状态与能耗之间的关系。其次,构建发电设备运行状态数学模型,从中提取发电设备运行状态多个特征信息,并利用双通道结构对提取的特征信息进行融合。然后,设计双通道多特征融合控制策略,以融合提取的数据特征。最后,计算对应的控制参数,通过计算发电设备运行过程中的能耗阈值,制定对应的电力设备绿色节能控制策略。试验结果表明,与以往的发电设备绿色节能控制方法相比,所提方法在实际应用中节能效益最高可达44.5%。该方法具有节能效益高、易于操作和维护、实时性好和灵活性高等特点,在发电设备绿色节能控制领域具有广阔的应用前景。

基于Vogit力学模型的照明系统节能控制研究

采用Vogit力学模型,构建照明系统离散动力学方程,分析照明系统状态空间变化特征,估计照明系统负载;引入电流灵敏度参量,结合照明系统电磁耦合特性,构建照明系统节能控制模型;通过自适应迭代处理实现自适应寻优,获取照明系统内环控制输出增益;根据照明系统节能控制带恒功率负载等效原理消除复阻抗,达到节能控制稳定的目的。以照明系统作为实验对象进行实验,结果表明该方法的节能控制效果较好,能够有效确保照明系统节能控制的稳定性。

电气节能与新能源技术的应用

随着电力电子技术的发展,电能逐渐被广泛应用于各个领域。在能源紧缺的时代背景下,加强电气节能技术应用,发展新能源技术,不仅能够缓解当前电能紧缺的问题,也能提升能源的利用率。本文阐述了电气节能与新能源技术应用的意义,探讨了电气节能技术的应用策略,围绕新能源技术应用于电信领域提出了几点措施。

电动车废热辅助空调系统的研究

针对目前电动车空调存在的节能性和低温适应性等问题,提出了一种电动车废热辅助热泵空调系统。该系统将多变频器协调控制技术、双级压缩循环技术、废热辅助热泵技术有机融合,通过仿真分析研究系统在不同运行状态下的系统性能。仿真结果表明:协调调节低压级压缩机和风扇电机的频率,可实现系统制冷/制热量和能效比的优化控制;合理设置单双级压缩的温度切换点,能提升制热性能、保证系统在低温工况下的可靠运行;利用废热辅助空气源热泵技术,能实现系统的节能。研究结果为减小空调系统对电动车续航里程的影响、推动电动车的普及提供了参考。

气垫带式输送机供气方式改进

气垫带式输送机因为将传统滚动摩擦替换为空气摩擦,所以总功率应该小于普通带式输送机,然而实际中功率消耗并不小。存在原因有供风方式不合适,造成很大的能量损耗,甚至出现空载飘带现象。通过改变供风方式,可以合理控制风压和风量,使输送带能够平稳支撑并运行。在保证气室大小及形状及总流量不变,只改变入口数量的情况下,通过ANSYS分析不同供气情况下气膜的压力分布情况,结果显示分流后气膜压力显著增大。

用于铝压延厂房油雾控制的环吸式排风罩设计方法

环吸式排风罩是针对铝压延加工工艺油雾散发特征而提出的一种高效捕集设备,可以大幅降低系统风量,从而减少能耗和降低碳排放量,但目前仍缺乏此类排风罩的通用设计方法。本文选取10个铝压延车间铝冷轧机及排风罩为研究对象,探究了不同轧机尺寸组合下排风罩罩口处污染物扩散断面尺寸和排风罩捕集性能,通过回归分析得到了排风罩罩口设计尺寸和设计风量的计算方法,可供工程设计人员参考。