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.

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.

A Comparative Analysis of the Sustainable Growth of Global Hydro, Solar, and Wind Power Systems (Renewable Energy Systems)

The unfettered reliance on fossil fuels for centuries has pushed the world to the brink of severe environmental crises. While individual studies on renewable energy generation capacity have been conducted, a comprehensive analysis is lacking. This study aims to address this gap by providing a comparative analysis of three major renewable energy sources—hydro, solar, and wind— and their current global utilization statistics. Additionally, it will examine the efficacy of fossil fuels and their detrimental impact on the environment. Global warming and its associated health consequences on the ecosystem are rapidly escalating. Without a complete decarbonization of our energy systems, environmental deterioration is poised to continue at an alarming rate. Fortunately, a plethora of traditional and renewable energy resources exist that have minimal or no environmental impact and have been available for years. However, these resources remain largely untapped. The full potential of RE resources hinges on the development of sustainable technologies to harness their energy to their fullest capacity. This study delves into the current global and regional RE utilization from 2013 to 2022, based on data from the International Renewable Energy Agency (IRENA) 2023. The focus is limited to the three primary renewable energy sources with the highest harnessing capacity in recent times. Employing appropriate mathematical analyses, the results reveal exponential growth in renewable energy, with an average annual generating capacity of 2353550.7 MW over the past decade. Hydroelectric power, solar power, and wind, among others, have played a significant role in the global penetration of renewable energy systems. The changing dynamics have propelled these RE resources into the spotlight in recent years, owing to their sustainability and environmental friendliness.

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.

Thermodynamic Analysis,Simulation and Optimization on Energy Savings of Ideal Internal Thermally Coupled Distillation Columns

Internal thermally coupled distillation columns (ITCDIC) are the frontier of distillation energy saving research. In this paper, a novel energy saving model of ideal ITCDIC and a simulation algorithm are presented,upon which a series of comparative studies on energy savings with conventional distillation columns are carried out. Furthermore, we present an optimization model of ideal ITCDIC, which can be used to achieve the maximum energy saving and find the optimal design parameters directly. The binary system of benzene-toluene is adopted for the illustrative example of simulation and optimization. The results show that the maximum energy saving of ITCDIC is 52.25% (compared with energy consumption of conventional distillation under the minimum reflux ratio operation); the optimal design parameters are obtained, where the rectifying section pressure and the feed thermal condition are Pr=0.3006 MPa and q=0.5107 respectively.

Parameters Optimization and Energy-Saving of Highway Tunnel Backlighting with LED

In order to acquire the most energy-saving luminairedistribution-parameters(LDPs)of highway tunnel interior zone backlighting,the parameters optimization model(POM)of backlighting for tunnel interior zone was established.Yanlieshan tunnel of Jiujing highway was taken as an example for the optimization.The optimal LDPs of the backlighting system of the tunnel interior zone were obtained by the POM,a comparison between the optimization results and those of Yanlieshan tunnel’s actual lighting system was performed,which showed that the optimized backlighting system with LED lamps installed according to the optimized LDPs could save energy remarkablely even under full capacity lighting condition.Illuminance and illuminance uniformity of the tunnel road surface still met the lighting demands even the LED lamp’s luminance decreased by 30%.A backlighting simulation experiment with the optimized backlighting LDPs for Yanlieshan tunnel was accomplished in the software Dialux.The simulation results basically agreed with the optimization calculated results from the POM which proved the correctness of the backlighting POM.

Key Points of Installation Technology and Analysis of Energy Saving Measures on HVAC Equipment

HVAC equipment is very concerned in the current equipment operation process.Its safety,reliability and comfort will have a greater impact on the production and life of common people.In some projects,there are some problems in the installation of HVAC equipment,such as imperfect installation scheme,low installation quality and random selection of equipment parameters.These seriously affect the normal operation of the equipment,and it is not easy to achieve energy saving of HVAC equipment.In the future installation of HVAC equipment,it is necessary to continuously optimize the HVAC equipment installation system,fully compare the reliability and feasibility of the equipment installation scheme,and strengthen the application of energy-saving technology of HVAC equipment.In this way,the use cost of the equipment can be reduced and the comprehensive quality of the equipment can be improved.Therefore,this paper discusses this further and puts forward reasonable suggestions.

Application of the waste heat recovery system and energy-saving in the strip continuous annealing furnace

The common problem of cold strip continuous annealing furnaces is high exhaust gas temperature and great energy consumption. Taking the cold-strip continuous annealing furnaces of Baosteel No. 4 cold mill plant as an example, several waste heat recovery systems in the annealing furnaces are compared and their advantages and disadvantages are analyzed through different energy-saving technologies.

Energy saving analysis of segment positioning in shield tunneling machine considering assembling path optimization

A motion parameter optimization method based on the objective of minimizing the total energy consumption in segment positioning was proposed for segment erector of shield tunneling machine. The segment positioning process was decomposed into rotation, lifting and sliding actions in deriving the energy calculation model of segment erection. The work of gravity was taken into account in the mathematical modeling of energy consumed by each actuator. In order to investigate the relationship between the work done by the actuator and the path moved along by the segment, the upward and downward directions as well as the operating quadrant of the segment erector were defined. Piecewise nonlinear function of energy was presented, of which the result is determined by closely coupled components as working parameters and some intermediate variables. Finally, the effectiveness of the optimization method was proved by conducting a case study with a segment erector for the tunnel with a diameter of 3 m and drawing comparisons between different assembling paths. The results show that the energy required by assembling a ring of segments along the optimized moving path can be reduced up to 5%. The method proposed in this work definitely provides an effective energy saving solution for shield tunneling machine.

Application of Energy Saving Technology in Trichlorosilane Distillation Purification Process

The trichlorosilane(TCS)purification process consumes a significant amount of energy to achieve the high purity requirement for TCS quality(99.9999%).This work proposed a series of energy saving technology to enhance the TCS purification process,including the conventional process,the conventional process coupled with heat-pump(HP),the multi-effect distillation process,and the dividing-wall columns process.All proposed schemes have been conceptually constructed by Aspen Plus.The design and optimization of the processes have been performed by the sensitivity analysis and the response surface methodology.Moreover,the energy consumption and total annual cost(TAC)for these schemes were discussed.The simulation results show that the TAC of the conventional process coupled with the integrated heat pump can reduce 50.5%of energy consumption as compared with the conventional process;the double-effect and three-effect processes can save 15.6%and 33.8%of energy consumption,respectively;the dividing wall column process and that coupled with the heat pump process can reduce by 22.3%and 48.1%of energy consumption,respectively.It can be found that the operating cost can be saved by using the heat pump technology,while the capital cost increases due to the investment in the compressor,when the processes coupled with the heat pump are used.These results demonstrate that the conventional process coupled with the HP technology has advantages over other distillation schemes for TCS purification in terms of the energy saving and economic effects.

Indicator system of energy efficient technologies evaluation of residential buildings in hot summer and cold winter regions of China

The related existing energy saving index system of buildings is deficient in direction, index coverage, depth, and technological and economic considerations. Aiming at the deficient existing research and with the advancement of energy saving of buildings in China from northern heating regions to southern hot summer and cold winter regions, selecting residential buildings in hot summer and cold winter regions as the research object, and through much evaluation index reference and repeated demonstrations and the borrowing of literature research home and abroad and relevant energy saving standards, filters and eliminates energy efficient technologies evaluation indexes according to the design principle of index system, the factors influencing the energy saving of residential buildings are evaluated, index system weight is established by adopting analytic hierarchy process, and finally the evaluation index system of energy saving technologies of residential buildings in hot summer and cold winter area of China is established. Each target layer includes five standard layer indexes and sixteen index layer indexes. The standard layer of evaluation index, namely primary indexes, includes the technological, energy saving effect, economic, environmental, and social indexes. The secondary indexes are selected based on the principles of concision, comprehensiveness, representativeness and operability.

Construction practice of market system for energy saving renovation of existing buildings

The energy-saving reconstruction market of existing buildings is a complex system.It includes three subsystems:service market,capital market and technology market.The service market takes the relationship between energy service companies and owners as the core to establish service associated relationships.The capital market is based on the mechanism of"investment guarantees and risk sharing"to form structures of the capital market.The technology market relies on the"industry-university-research"mode to build technology supporting platforms.Being interdependent and mutually restricted,the three subsystems form the complete system of existing buildings in energy-saving reconstruction.

Energy-saving Technology of Vent in Passive Solar Wall of Rural House of Severe Cold Region

This paper aims at solving the problems of low thermal collection rate,inconvenient maintenance,hindering indoor using during the application of passive solar technologies in rural houses in severe cold region.All these defects prevent the passive solar houses' further development. This paper chooses trombe wall,which has higher thermal efficiency of the passive solar house,as research object. The traditional vent is improved into a new type of ventilation device. This improvement overcomes the shortcoming,which traditional vent loses huge heat,and simplifies the construction of vent. Comparing with traditional trombe wall,the energy saving rate is 15. 69%.

Energy saving analysis for CO_(2)–O_(2)mixed injection technology in converter steelmaking

Energy-saving in China's iron and steel industry still relies on the development and improvement of short-term energy saving technologies.Therefore,a special converter smelting technology incorporating energy saving was proposed.To evaluate the energy-saving potential of the CO_(2)–O_(2)mixed injection(COMI)technology,collected production data were used to develop an improved techno-economic model.Calculations reveal that the technology can save energy through auxiliary material consumption,sensible heat of solid by-product,iron loss reduction,and energy recovery.The application of COMI technology in an enterprise is cost effective,involving the energy saving potential of 0.206 GJ/t,the cost of conserved energy of−48.83 yuan/GJ,and a simple payback period of 0.35 year for a 60-million-yuan investment.Sensitivity analysis shows that the investment cost and discount rate primarily influence the cost of conserved energy of the technology.As the discount rate increased,the cost of conserved energy also gradually increased.Overall,the COMI technology is an energy-saving technology with good development prospects.

Design and Application of Third-order Denitration Online Control Technology

In order to alleviate the pressure of environmental protection and further strengthen the monitoring and control of NOx emission of thermal power units, combining with the transformation of boiler low-nitrogen burner, combustion optimization, static and dynamic ratio of air and coal, and SCR denitration system process, third-order NOx online control technology was designed and applied, which takes the combustion security, boiler efficiency and environmental evaluation into account and provide reference for thermal power units to deepen energy conservation and emission reduction.

Numerical simulation investigations of energy-saving diffuser of main fan

Based on the boundary condition of field engineering, numerical simulations of28 conditions of existing diffusers of 3 structure types were investigated by ComputationalFluid Dynamics software package, and there were the problems of larger structure resistanceand lower diffusing efficiency of these diffusers by analysis of CFD results.Thestructure outlines of the energy-saving diffuser were constructed by the application ofstream function and potential function superimposing.On the basis of numerical simulationsof energy-saving diffusers of 5 area-enlarging ratios, structural resistances and diffusingefficiencies of 5 energy-saving diffusers were comparatively analyzed, and therange from 2.00 to 2.31 of the rational area-enlarging ratio of energy-saving diffusers wasderived.The optimization area-enlarging ratio of the energy-saving diffuser was presently2.28 through comparable analysis.From the above, the results show that the coefficient ofperformance of the energy-saving diffuser is better than 3 existing diffusers.

SIMULATION ANALYSIS AND OPTIMIZATION OF STEAM REFORMING PROCESS FOR A LARGE-SCALE AMMONIA PLANT

The present paper shows how the Schuster Schwarzschild method developed originally inastrophysics can be adopted to simulate the performance of the primary reforming furnace in an am-monia plant.This method facilitates the simulation of heat transfer and reaction in the furnace andimproves the computational efficiency.Simulation analysis is carried out to find ways of saving ener-gy.Appropriate reduction in fuel gas loading and partially shifting of the reforming load from theprimary to the secondary reformer by regulating the operating conditions can result in substantial en-ergy saving.Optimization calculations with various objective functions and constraints required areperformed.The optimization results may serve as guideline for plant operation and control.