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.

Research on the cooperative train control method in the metro system for energy saving

Purpose–To address the problem that the current train operation mode that train selects one of several offline pre-generated control schemes before the departure and operates following the scheme after the departure,energy-saving performance of the whole metro system cannot be guaranteed.Design/methodology/approach–A cooperative train control framework is formulated to regulate a novel train operation mode.The classic train four-phase control strategy is improved for generating specific energy-efficient control schemes for each train.An improved brute force(BF)algorithm with a two-layer searching idea is designed to solve the optimisation model of energy-efficient train control schemes.Findings–Case studies on the actual metro line in Guangzhou,China verify the effectiveness of the proposed train control methods compared with four-phase control strategy under different kinds of train operation scenarios and calculation parameters.The verification on the computation efficiency as well as accuracy of the proposed algorithm indicates that it meets the requirement of online optimisation.Originality/value–Most existing studies optimised energy-efficient train timetable or train control strategies through an offline process,which has a defect in coping with the disturbance or delays effectively and promptly during real-time train operation.This paper studies an online optimisation of cooperative train control based on the rolling optimisation idea,where energy-efficient train operation can be realised once train running time is determined,thus mitigating the impact of unpredictable operation situations on the energy-saving performance of trains.

Research on Energy Efficiency Characteristics of Mining Shovel Hoisting and Slewing System Driven by Hydraulic-Electric Hybrid System

Mining shovel is a crucial piece of equipment for high-efficiency production in open-pit mining and stands as one of the largest energy consumption sources in mining.However,substantial energy waste occurs during the descent of the hoisting system or the deceleration of the slewing platform.To reduce the energy loss,an innovative hydrau-lic-electric hybrid drive system is proposed,in which a hydraulic pump/motor connected with an accumulator is added to assist the electric motor to drive the hoisting system or slewing platform,recycling kinetic and potential energy.The utilization of the kinetic and potential energy reduces the energy loss and installed power of the min-ing shovel.Meanwhile,the reliability of the mining shovel pure electric drive system also can be increased.In this paper,the hydraulic-electric hybrid driving principle is introduced,a small-scale testbed is set up to verify the feasibil-ity of the system,and a co-simulation model of the proposed system is established to clarify the system operation and energy characteristics.The test and simulation results show that,by adopting the proposed system,compared with the traditional purely electric driving system,the peak power and energy consumption of the hoisting electric motor are reduced by 36.7%and 29.7%,respectively.Similarly,the slewing electric motor experiences a significant decrease in peak power by 86.9%and a reduction in energy consumption by 59.4%.The proposed system expands the application area of the hydraulic electric hybrid drive system and provides a reference for its application in over-sized and super heavy equipment.

Analysis of Power Matching on Energy Savings of a Pneumatic Rotary Actuator Servo-Control System

When saving energy in a pneumatic system,the problem of energy losses is usually solved by reducing the air supply pressure.The power-matching method is applied to optimize the air-supply pressure of the pneumatic system,and the energy-saving effect is verified by experiments.First,the experimental platform of a pneumatic rotary actuator servo-control system is built,and the mechanism of the valve-controlled cylinder system is analyzed.Then,the output power characteristics and load characteristics of the system are derived,and their characteristic curves are drawn.The employed air compressor is considered as a constant-pressure source of a quantitative pump,and the power characteristic of the system is matched.The power source characteristic curve should envelope the output characteristic curve and load characteristic curve.The minimum gas supply pressure obtained by power matching represents the optimal gas supply pressure.The comparative experiments under two different gas supply pressure conditions show that the system under the optimal gas supply pressure can greatly reduce energy losses.

Self-sustained Oscillation Pulsed Air Blowing System for Energy Saving

Currently, many studies have been made for years on dimensions of pneumatic nozzle, which influence the flow characteristic of blowing system. For the purpose of outputting the same blowing force, the supply pressure could be reduced by decreasing the ratio of length to diameter of nozzle. The friction between high speed air and pipe wall would be reduced if the nozzle is designed to be converging shape comparing with straight shape. But the volume flow and pressure, discussed in these studies, do not describe energy loss of the blowing system directly. Pneumatic power is an innovative principle to estimate pneumatic system’s energy consumption directly. Based on the above principle, a pulse blowing method is put forward for saving energy. A flow experiment is carried out, in which the high speed air flows from the pulse blowing system and continuous blowing system respectively to a plate with grease on top. Supply pressure and the volume of air used for removing the grease are measured to calculate energy consumption. From the experiment result, the pulse blowing system performs to conserve energy comparing with the continuous blowing system. The frequency and duty ratio of pulse flow influence the blowing characteristic. The pulse blowing system performs to be the most efficient at the specified frequency and duty ratio. Then a pneumatic self-oscillated method based on air operated valve is put forward to generate pulse flow. A simulation is made about dynamic modeling the air operated valve and calculating the motion of the valve core and output pressure. The simulation result verifies the system to be able to generate pulse flow, and predicts the key parameters of the frequency and duty ratio measured by experiment well. Finally, on the basis of simplifying and solution of the pulse blowing system’s mathematic model, the relationship between system’s frequency duty ratio and the dimensions of components is simply described with four algebraic equations. The system could be designed with specified frequency and duty ratio according to the four equations. This study provides theoretical basis for designing energy-saving air blowing system.

Research on Energy-Saving Performance of Intermittent Heating for Rooms in Hot Summer&ColdWinter Zone

In the hot summer&cold winter zone in China,intermittent heating space for rooms is widely used.However,in comparison with continuous space heating,the energy-saving performance of intermittent space heating has not been sufficiently investigated.This paper studied the factors influencing the energy performance of intermittent heating for the representativeoffice inhot summer&coldwinter zone.Basedon theheatbalancemethod,adynamic thermalmodel of the intermittent heating roomwas built and tested by experiments.And then,it analyzed the total space heating load,the amount of energy saving and energy saving ratio of the intermittent heating under different preheating hours,occupation hours,required roomtemperatures,air change rates,overall heat transfer coefficients(U-value)of windows and wall materials.If the adjacent rooms were not heated,for a typical room occupied about 10 h a day,the energy-saving ratio of intermittent heating was about 30%compared with continuous heating.But the preheating power was higher than two times of continuous heating.The results also indicated that the occupation hours had a significant effect on energy saving amount and ratio,it should be noted that the energy saving ratio by intermittent heating was much lower than the unoccupied period ratio.Relative to other factors,the heating temperatures,room air change rates and U-value of windows,and room envelope materials had little effect on energy efficiency.If the adjacent rooms were heated in the same manner as the roomin question,the energy-saving ratio of the total load of intermittent heating was heavily reduced to 8.46%.

Low Carbon Building Design Optimization Based on Intelligent Energy Management System

The construction of relevant standards for building carbon emission assessment in China has just started,and the quantitative analysis method and evaluation system are still imperfect,which hinders the development of low-carbon building design.Therefore,the use of intelligent energy management system is very necessary.The purpose of this paper is to explore the design optimization of low-carbon buildings based on intelligent energy management systems.Based on the proposed quantitative method of building carbon emission,this paper establishes the quota theoretical system of building carbon emission analysis,and develops the quota based carbon emission calculation software.Smart energy management system is a low-carbon energy-saving system based on the reference of large-scale building energy-saving system and combined with energy consumption.It provides a fast and effective calculation tool for the quantitative evaluation of carbon emission of construction projects,so as to realize the carbon emission control and optimization in the early stage of architectural design and construction.On this basis,the evaluation,analysis and calculation method of building structure based on carbon reduction target is proposed,combined with the carbon emission quota management standard proposed in this paper.Taking small high-rise residential buildings as an example,this paper compares and analyzes different building structural systems from the perspectives of structural performance,economy and carbon emission level.It provides a reference for the design and evaluation of low-carbon building structures.The smart energy management system collects user energy use parameters.It uses time period and time sequence to obtain a large amount of data for analysis and integration,which provides users with intuitive energy consumption data.Compared with the traditional architectural design method,the industrialized construction method can save 589.22 megajoules(MJ)per square meter.Based on 29270 megajoules(MJ)per ton of standard coal,the construction area of the case is about 8000 m2,and the energy saving of residential buildings is 161.04 tons of standard coal.This research is of great significance in reducing the carbon emission intensity of buildings.

Optimal energy saving in DC railway system withon-board energy storage system by using peak demand cutting strategy

A problem of peak power in DC-electrified railway systems is mainly caused by train power demand during acceleration.If this power is reduced,substation peak power will be significantly decreased.This paper presents a study on optimal energy saving in DC-electrified railway with on-board energy storage system(OBESS) by using peak demand cutting strategy under different trip time controls.The proposed strategy uses OBESS to store recovered braking energy and find an appropriated time to deliver the stored energy back to the power network in such a way that peak power of every substations is reduced.Bangkok Mass Transit System(BTS)-Silom Line in Thailand is used to test and verify the proposed strategy.The results show that substation peak power is reduced by63.49% and net energy consumption is reduced by 15.56%using coasting and deceleration trip time control.

ENERGY-SAVING MATCHING STRATEGY AND EXPERIMENTAL STUDY OF PUMPING SYSTEM FOR TRUCK-MOUNTED CONCRETE PUMP

Aiming at the high fuel consumption and use-cost of truck-mounted concrete pump , an energy-saving matching strategy of pumping system is presented and the experimental study is conducted.Since pumping system occupies most resources of engine , the matching strategy between engine and main pump is analyzed to meet the load demand and reduce the engine rational speed drop.The testing method is established to measure the fuel consumption of engine under various working conditions , and the experimental data are analyzed to find the law of the fuel consumption of engine.The system performance can be improved by adjusting the system input value.Finally , the energy-saving matching strategy is established to reduce the fuel consumption of truck for unit workload , which provides a new approach for the energy-saving of truck-mounted concrete pump.

Optimization of Finishing Process and Energy Savings in Denim Textile Facility

Denim is widely accepted among exported textile products due to its aesthetics, appearance, and fashion. Practitioners employed several physical or chemical treatments to improve denim qualities in denim finishing operations. So, several treatment processes, including enzymatic, bleaching, singeing, heat set, and ozone finish, are used, which made this processing more energy consumption and time-consuming. Therefore, it is significant to investigate how changing the chemicals and raw ingredients could improve the finishing process, which is environmentally and economically beneficial for sustainable production practices in the denim finishing process. This study’s research design comprises an experimental investigation in a denim plant in Bangladesh. Two different fabrics were chosen to analyze, determining the potential savings of finishing on the denim fabrics’ performance characteristics. By deducting singeing and heat-set processes, the researchers ran an experimental process by maintaining the same length of fabric. Then, the impacts of finishing process optimization on the mechanical, thermal, and comfort parameters of drape, stiffness, and tear strength were examined. The study’s findings demonstrated that this experiment increased productivity and reduced the finishing unit’s energy consumption without compromising the denim fabrics’ quality. This study significantly impacts environmental sustainability by preserving limited energy resources and manufacturing denim finishing processes.

An Energy-Saving Control Strategy on Central Air-Conditioning System

An energy-saving control strategy based on predictive control for central air-conditioning systems is proposed in this paper. The cold load model is developed to describe the dynamic characteristics of temperature control systems, and then parameters in the cold load model and in the central air-conditioning system model are estimated. Generalized predictive control (GPC) is used to establish an optimization model to minimize the consumption of energy and the control error of temperature. The simulated annealing (SA) algorithm, combined with quadratic programming, is adopted to solve the optimal problem. Contrasted with the simulation of traditional PID control, the results prove the effectiveness of this proposed strategy.

Research on Potential Energy Recovery System of 16T Wheeled Hybrid Excavator

The system translates the arm/boom/buck's potential energy into electrical energy and then the electrical energy is stored in a storage device.This study develops a set of energy management strategy to make the recoverable energy recycling efficiently.This energy of traditional excavator is lost in the form of heat energy,which is wasteful,and makes the component's temperature higher and higher to reduce the machine's life.Research on this system not only conforms to the current topic of energy crisis,but also mates with the actual engineering,so it is significant to research that.

Summary of Steam System Optimization and Energy Saving and Carbon Reduction Practice in Yanshan Petrochemical Company

This paper analyzes the main problems of Sinopec Beijing Yanshan Petrochemical Co.,Ltd.,such as decentralized steam system layout,many types of fuels,obvious increase in fuel cost,low operation efficiency of turbine and boiler and high self consumption loss,and puts forward and implements optimization and improvement measures such as pressure raising transformation of natural gas system,adjustment of energy consumption structure,reduction of energy consumption cost,improvement of steam production quality and equipment efficiency.The results showed that compared with the fuel consumption in 2018,the consumption of coal coke was reduced by 550000 t,the consumption of natural gas was increased by 170000 t,and the total consumption of fuel gas and fuel oil was increased by 50000 t,equivalent to 246000 t of standard coal;the purchased electricity was increased by about 5×10^(8) kW·h.Green power trading and 14.76 MW distributed photovoltaic projects were carried out.According to the calculation of 1400-1600 h annual power generation in class II photovoltaic areas and the emission factor of North China regional power grid baseline,the annual emission reduction was about 55000 t CO_(2) in 2021.After the above transformation,the goal of zero-coking is achieved;the steam consumption of units is reduced by 21.5%,the steam production of boilers is reduced by 24.9%,and the annual emission reduction is about 760000 t CO_(2),which has achieved good results.

Research on Energy Saving Technology of Load Sensitive Variable Steering System for Vehicles

In view of the large energy loss problem in the traditional full hydraulic steering system,a scheme of replacing the ordinary pump with the priority valve with the load sensitive variable pump is proposed to make the variable pump provide the corresponding flow rate according to the needs of the steering system to achieve the purpose of energy saving.Through the establishment of the system AMESim simulation model,the data comparison shows that the energy loss of the load sensitive variable steering system is significantly reduced relative to the traditional full hydraulic steering system.

Electrochromism-induced adaptive fresh air pre-handling system for building energy saving

Building fresh air supply needs to meet certain regulations and fit people’s ever-growing indoor air quality de-mand.However,fresh air handling requires huge energy consumption that goes against the goal of net-zero energy buildings.Thus,in this work,an adaptive fresh air pre-handling system is designed to reduce the cool-ing and heating loads of HVAC system.The sky-facing surface of the system uses electrochromic mechanism to manipulate the optical properties and thus make full use of solar energy(solar heating)and deep space cold source(radiative cooling)by switching between heating and cooling modes.In the cooling mode,the sky-facing surface shows a transmittance of down to zero,while the reflectance is high at 0.89 on average.In the heating mode,the electrochromic glass is highly transparent,allowing the sunlight to reach the solar heat absorber.To obtain the energy-saving potential under different climates,six cities were selected from various climate regions in China.Results show that the adaptive fresh air pre-handling system can be effective in up to 55.4%time of a year.The maximum energy-saving ratios for medium office,warehouse,and single-family house can reach up to 11.52%,26.62%,and 18.29%,respectively.In addition,the system shows multi-climate adaptability and broad application scenarios,making it a potential solution to building energy saving.

Dynamics of electromagnetic slip coupling for hydraulic power steering application and its energy-saving characteristics

To improve high-speed road feel and enhance energetic efficiency of hydraulic power steering(HPS) system in heavy-duty vehicles, an electromagnetic slip coupling(ESC) was applied to the steering system, which regulated discharge flow of steering pump to realize variable assist characteristic as well as uniquely transfer on-demand power from engine to steering pump. The model of ESC was established and the dynamic characteristics of ESC were presented by the way of simulation and experiment. Upon the layout of the assist characteristics, output torque of ESC was derived. Based on the ESC model, the output torque characteristics of ESC were simulated under steering situation and straight driving situation, respectively. The consistency of simulated ESC output torque and the one deduced from assist characteristics verifies the correctness of the ESC dynamic model. To illustrate energy saving characteristics of ESC-HPS, energy consumption comparison of ESC-HPS and conventional HPS was carried out qualitatively and quantitatively. It follows that the energy consumption of ESC-HPS decreases by 50% compared with that of HPS.

Conceptual design of energy-saving stripping process for industrial sour water

Sour water contains ammonia,carbon dioxide,and hydrogen sulfides,producing from oil refining,coking,and coal gasification.To reduce the energy consumption in sour water stripping,a novel process is proposed which integrates with the bottom flashing mechanical vapor recompression heat pump(MVRHP)for treating such wastewater.Here,Aspen PlusTM as a powerful set of chemical process simulation software is utilized to investigate the economy and feasibility of the novel process.Comparison of the results of two process simulations,it can be seen that it is possible to reduce the total annual cost by nearly 45%to adopt the novel process,despite the capital investment increase 45%more than the conventional process.Thus,the provided conceptual design will play a guiding role in the industrialization of the process.

Technical Analysis of Energy Saving and Emission Reducing in China's Cement Industry Based on LEAP Model

[Objective] The study aimed at evaluating the ability to save energy and reduce CO2 emission in China＇s cement industry. [Method] Based on long-term energy alternative planning system software （LEAP）, ＂LEAP of China＇s cement industry＂ model was established to simulate energy conservation and emission reduction in China＇s cement industry from 2010 to 2040 in different technologic situations. E ResultJ To save ener- gy and reduce CO2 emissions, new dry process kiln has priority over other technologies or measures, followed by equipment enlargement, mechani- cal shaft kiln, power generation system based on waste heat, as well as high-efficiency and energy-saving grinding technology, and new prepara- tion technology. If all the advanced technologies and measures are adopted, energy consumption and C02 emissions can be reduced by about 40.76% and 42.97% respectively. [ Condusion] LEAP of model is suitable for analyzing energy saving and emission reducing in China＇s cement industry and other industrial fields.

A multi-objective train-scheduling optimization model considering locomotive assignment and segment emission constraints for energy saving

Energy saving and emission reduction for railway systems should not only be studied from a technical perspective but should also be focused on management and economics. On the basis of relevant trainscheduling models for train operation management, in this paper we introduce an extended multi-objective trainscheduling optimization model considering locomotive assignment and segment emission constraints for energy saving. The objective of setting up this model is to reduce the energy and emission cost as well as total passenger- time. The decision variables include continuous variables such as train arrival and departure time, and binary vari- ables such as locomotive assignment and segment occu- pancy. The constraints are concerned with train movement, trip time, headway, and segment emission, etc. To obtain a non-dominated satisfactory solution on these objectives, a fuzzy multi-objective optimization algorithm is employed to solve the model. Finally, a numerical example is performed and used to compare the proposed model with the existing model. The results show that the proposed model can reduce the energy consumption, meet exhausts emission demands effectively by optimal locomotive assignment, and its solution methodology is effective.

Runtime Energy Savings Based on Machine Learning Models for Multicore Applications

To improve the power consumption of parallel applications at the runtime, modern processors provide frequency scaling and power limiting capabilities. In this work, a runtime strategy is proposed to maximize energy savings under a given performance degradation. Machine learning techniques were utilized to develop performance models which would provide accurate performance prediction with change in operating core-uncore frequency. Experiments, performed on a node (28 cores) of a modern computing platform showed significant energy savings of as much as 26% with performance degradation of as low as 5% under the proposed strategy compared with the execution in the unlimited power case.