Waste Heat Recovery Technologies Research Articles

Bi-Level Operation Optimization and Performance Analysis for a Distributed Energy System with Energy Network

The increasing energy crisis and environmental problems promote the development of distributed energy systems (DESs) that utilize combined heat and power technology, renewable energy technology, and waste heat recovery technology to meet various load requirements. Although there is existing work and research on a variety of DESs, most previous studies tend to focus on energy production with little consideration of a distributed energy network and its energy loss, which results in large errors in energy-efficiency calculations and performance analyses. In this paper, a new DES model is proposed with full consideration of an energy network and the full use of solar energy, terrestrial heat, and exhaust gases. At the same time, an effective bi-level optimization method is also proposed for the daily operation of the DES in order to improve the system performance and benefits in the energy, the economy, and the environment. Specifically, the co-generation energy station and water heating network in the DES are optimized separately with two different optimization models. The first-level optimization model is used to seek the optimal values of water mass flow rate and water temperature of the water heating network, and the second-level optimization model is built to determine the optimal energy purchasing strategy and the optimal energy outputs of the co-generation energy station. In order to verify the advantages and effectiveness of the proposed system and method, a contrastive simulation study is undertaken to provide a comparison of the global optimization method. Simulation results show that energy loss, energy cost, and energy consumption of the DES using the bi-level optimization operation strategy only account for 22.51%, 33.42%, and 51.31% of the quantities of the global optimization method, respectively. The hourly curves of the optimal operating variables also demonstrate that the proposed bi-level optimization method can improve the operating stability of the DES better than the global optimization method.

Techno-economic and environmental analysis of decarbonization pathways for cement plants in Uzbekistan

The cement industry is a major contributor to global carbon emissions and is characterized by high energy waste, necessitating urgent mitigation efforts. This study explores decarbonization pathways, including energy efficiency, clinker substitution, alternative fuels, and carbon capture, storage, and utilization technologies, for a 1 Mt/year cement plant in Uzbekistan. Waste heat recovery and CO2 capture technologies are identified as the most effective methods for this plant because of their high efficiency and sustainability potential. By using modeling tools such as Aspen Plus and Aspen Custom Modeler, various scenarios, including the cement plant baseline, amine-based CO2 absorption, membrane CO2 separation, and WHR units, are investigated to assess their techno-economic and environmental impacts. The study establishes design parameters for each unit and calculates both capital and operational costs. Compared with conventional amine absorption, the membrane separation process reduces the clinker cost, levelized cost of clinker, CO2 avoided cost, and CO2 capture cost by 31 %, 34.3 %, 72 %, and 70 %, respectively. The implementation of a waste heat recovery system with amine absorption and membrane separation further reduces annual indirect CO2 emissions by 17 % and 35 %, respectively, thereby lowering operating costs. Membrane separation systems prove to be more economical in terms of both capital and operational expenses, particularly when integrated with heat recovery systems, effectively offsetting the higher costs associated with amine-based systems.

Waste heat recovery technologies in modern internal combustion engines

Waste heat recovery (WHR) technologies in internal combustion engines (ICEs) outline various methods to harness wasted energy for improved efficiency and reduced emissions. The discussion covers heat exchangers, turbo-compounding, bottoming cycles, thermoelectric generators (TEGs), thermochemical recuperation (TCR), thermoacoustic conversion, and absorption refrigeration. Each technology's principles, applications, benefits, and challenges are explored, highlighting advancements and innovations from industry leaders. The abstract underscores the ongoing efforts to maximize energy efficiency and minimize environmental impact in ICEs across diverse vehicle types and applications.

Fluid selection and parametric analysis of organic Rankine cycle applicable to the turboshaft engine with a recuperator

With ever increasing fossil fuel price and growing demands in cutting emissions, waste heat recovery (WHR) appears as a promising pathway to improve propulsion system performance, which can be potentially achieved by incorporating a recuperator. This paper explores the advantages and potentiality of further recovering exhaust heat from recuperated turboshaft engine through the concept of organic Rankine cycle (ORC) to improve fuel economy and thermal efficiency. For the intended application, working fluid selection is conducted after systematic consideration of thermophysical properties, environmental impact, health and safety issues. Furthermore, parametric analysis is carried out from the viewpoint of thermodynamics, and the genetic algorithm is also employed to obtain the maximum net power output. Targeting the implicit coupling between recuperator effectiveness and ORC performance, the potential advantages of the combined engine-ORC system are comprehensively evaluated at different operational regimes. The influence of flight condition is also discussed through sensitivity simulations for different altitudes. Results reveal that the combination of the recuperated engine with ORC cycle operated using acetone generally offers the greatest benefits, significantly reducing specific fuel consumption by 46%–59 % relative to the baseline simple-cycle engine, depending on the availability of heat source. This analytical work contributes to provide valuable insights into WHR technologies in the aviation industry.

Evaluating long-term operational data of a Very Large Crude Carrier: Assessing the diesel engines waste heat potential for integrating ORC systems

Given the spotlight on waste heat recovery (WHR) technologies for decarbonizing the shipping industry, critically assessing waste heat from propulsion and auxiliary engines using actual data is crucial for accurately predicting fuel and carbon savings. This paper addresses this by applying advanced data processing, considering voyage characteristics, and developing methods for mapping waste heat from main engine (ME) and diesel gensets (DGs) operations using long-term operational data from a Very Large Crude Carrier (VLCC) case study. Two methods predict unrecorded air mass flows by implementing heat balance: one using measured temperature values and the other estimating exhaust gas mass flow rates based on fuel oil consumption. Within the main objectives of this study is to examine the impacts of employing the exhaust gases of both ME and DGs to evaporate recuperative ORC working fluid on power output and vessel annual carbon savings, with the formed diesel engines operational profiles serving as inputs. Simulations show a power output of 530 kW using ME exhaust gases, increasing to 653 kW and 741 kW with DGs integration for R245fa and R1233zd(E) as the selected ORC working fluids, respectively. The proposed solutions can reduce annual CO2 emissions by 4 % to 7 %.

Potential of solid oxide fuel cells as marine engine assisted by combined cooling and power cogeneration systems

Switching to solid oxide fuel cell-gas turbine in marine applications can contribute to carbon reduction strategy. Integrating waste heat recovery technology can potentially meet the required cooling and power demands. This paper presents four combined cooling and power systems, each combining solid oxide fuel cell-gas turbine, supercritical CO2 cycle, and refrigeration cycle integration. First, the thermodynamic models of the four systems were constructed. Next, the performance of each integrated system was studied based on energy, exergy, economic, and environmental metrics. A multi-objective optimization approach was then applied to each system, balancing efficiency with cost. Results showed that the environmental penalty cost rate was 5.24 $/h at a fuel molar flow rate of 1.4 mol/s. The solid oxide fuel cell-gas turbine, regenerative supercritical CO2 Brayton cycle, and ejector expansion refrigeration cycle system offers the lowest cost rate of 44.40 $/h. Meanwhile, the solid oxide fuel cell-gas turbine, regenerative supercritical CO2 Brayton cycle, and absorption refrigeration cycle system achieves the highest energy efficiency (77.35 %) and cooling capacity (86.39 kW), indicating superior thermodynamic performance. This article provides a reference for the application of the solid oxide fuel cell-waste heat recovery system in marine transportation.

A Review of Energy-Efficient Technologies and Decarbonating Solutions for Process Heat in the Food Industry

Heat is involved in many processes in the food industry: drying, dissolving, centrifugation, extraction, cleaning, washing, and cooling. Heat generation encompasses nearly all processes. This review first presents two representative case studies in order to identify which processes rely on the major energy consumption and greenhouse gas (GHG) emissions. Energy-saving and decarbonating potential solutions are explored through a thorough review of technologies employed in refrigeration, heat generation, waste heat recovery, and thermal energy storage. Information from industrial plants is collected to show their performance under real conditions. The replacement of high-GWP (global warming potential) refrigerants by natural fluids in the refrigeration sector acts to lower GHG emissions. Being the greatest consumers, the heat generation technologies are compared using the levelized cost of heat (LCOH). This analysis shows that absorption heat transformers and high-temperature heat pumps are the most interesting technologies from the economic and decarbonation points of view, while waste heat recovery technologies present the shortest payback periods. In all sectors, energy efficiency improvements on components, storage technologies, polygeneration systems, the concept of smart industry, and the penetration of renewable energy sources appear as valuable pathways.

Working fluid pair selection of thermally integrated pumped thermal electricity storage system for waste heat recovery and energy storage

Global issues such as the energy crisis and carbon emissions impulse the development of waste heat recovery and energy storage technologies. In most practical industrial scenarios, the electricity supply and consumption cannot be perfectly matched and effective utilization of waste heat is in urgent need. In the present study, we develop a mathematical model to evaluate the thermally integrated pumped thermal electricity storage (TI-PTES) system to achieve off-peak electricity storage along with low-grade waste heat recovery. A double-layer optimization for screening working fluid pairs with high round-trip efficiency is carried out from 24 fluids of the heat pump and 21 fluids of the Organic Rankine cycle (ORC). In the first-layer multi-objective optimization, 3 types of working fluid pair combination strategies are compared and the great improvement of round-trip efficiency by using zeotropic fluids is proved. Among 7 energy storage temperatures covering from 393.15 K to 423.15 K with an increment interval of 5 K, the highest round-trip efficiency of 101.29% is achieved by adopting the zeotropic fluid pair [90Diethyl ether_10Pentane - 80Butane_20Pentane] at 398.15 K. Furthermore, in the second-layer single-objective optimization, the thermo-economic performance indicators of TI-PTES is evaluated and compared under different designing weighting factor groups, which effectively contributes to the screening of working fluids according to designer's trade-off. Finally, through varying energy storage temperatures and designing weighting factors, optimal working fluid pair recommendations including pure fluids and zeotropic ones were proposed to the fluid selection of TI-PTES.

Theoretical and experimental study on total heat recovery of condensing gas boiler flue gas by gas engine-driven compression heat pump

How to improve the utilization efficiency of natural gas and achieve the goal of carbon reduction has gradually become the focus of people’s attention. The exhaust temperature of the condensing gas boiler is between 50℃ and 80℃, which still contains some heat that is not used, so it is necessary to recover this part of the heat. This paper mainly studies the total heat recovery and utilization of waste heat from low-temperature flue gas of condensing gas boiler. In the research field of gas boiler flue gas waste heat recovery, the use of gas compression heat pump to recover gas boiler flue gas waste heat is still very few. Based on the principle of reducing the cold source temperature, a low-temperature flue gas recovery scheme of a gas engine-driven compression heat pump coupled condensing gas boiler is proposed. The low-temperature chilled water produced by gas engine-driven compression heat pump is used to recover flue gas waste heat from condensing gas boiler and gas engine, which can improve the utilization efficiency of natural gas and eliminate the “white smoke phenomenon” simultaneously. In addition, the waste heat of flue gas is used as the low-temperature heat source of gas engine-driven compression heat pump to ensure the stable operation of the heat pump in the low-temperature environment. The flue gas waste heat recovery technology has been improved compared with other flue gas waste heat recovery technologies in terms of primary energy utilization efficiency, system stability, corrosion resistance of flue gas heat exchangers, and investment recovery cycle. The experimental results show that when the water inlet temperature of the flue gas heat exchanger is 15℃, the overall power of the unit can reach 645 kW, and the final exhaust temperature is below 25℃. The overall primary energy utilization rate of the GEHP&CB can reach 110 %, which is 10 %∼20 % higher than that of the condensing gas boiler. The payback period of the increased initial investment is 1.4 heating seasons. Due to the improvement of natural gas utilization efficiency significantly reduces natural gas consumption and pollutant discharge.

Triple effect absorption refrigeration systems for the deep recovery of low grade waste heat

With regard to energy conservation, low grade waste heat recovery technology is attracting significant interest. The absorption refrigeration can significantly utilize waste heat. The current researches have devoted little attention to the recovery of waste heat at lower temperature. This paper presents three triple effect absorption refrigeration systems for the deep recovery of low grade waste heat, which can make use of more waste heat as low as 60 °C. The involvement of absorption heat transformer cycle enables the proposed systems to exploit waste heat at lower temperature. The models of three systems are established using EES software. Energy, exergy and economic analysis of three systems are conducted. The results indicate that the best of three systems can achieve a coefficiency of performance of 0.178 and the maximum exergy efficiency is 0.190. The triple effect absorption refrigeration systems not only generate more cold energy, but also demonstrate better economic performance than the previous cascade absorption refrigeration system. Except for the first system, the other two systems achieve reductions of 8.7% and 15.2% in the cost of unit cold energy respectively. This paper provides three novel approaches for producing high grade cool energy from lower temperature of waste heat.

Experimental and simulation study on a new gradient waste heat recovery system with a wider application range

This paper proposes a cascade sustainable waste heat recovery technology with low power consumption and the ability to recover waste heat in a wider temperature range, namely, the Absorption-Compression Coupled Heat Pump System. Experiments and simulations were conducted to reveal the effects of different factors on system performance. The results demonstrate that the coefficient of performance and exergy efficiency of the new system increase with an increase in generator outlet water temperature. The coefficient of performance of the new system decreases with an increase in supply heating water inlet water temperature, while the exergy efficiency increases with an increase in supply heating water inlet water temperature. As intermediate temperature increases, the coefficient of performance of new system shows a trend of first increasing and then decreasing, the total heating shows a trend of first increasing and then stabilizing, and the exergy efficiency shows a decreasing trend. Compared to single-effect absorption heat pump system, the new system can recover heat at lower heat source temperatures, and compared to compression heat pump system, it can reduce electricity consumption. Finally, by comparing with experimental data, it was found that the proposed model has good reliability, with a comprehensive error within ±7 %.

Design of an innovative system for hydrogen production by electrolysis using waste heat recovery technology in natural gas engines

This research proposes designing and implementing a system to produce hydrogen, utilizing the thermal energy from the exhaust gases in a natural gas engine. For the construction of the system, a thermoelectric generator was used to convert the thermal energy from the exhaust gases into electrical power and an electrolyzer bank to produce hydrogen. The system was evaluated using a natural gas engine, which operated at a constant speed (2400 rpm) and six load conditions (20 %, 40 %, 60 %, 80 %, and 100 %). The effect of hydrogen on the engine was evaluated with fuel mixtures (NG + 10 % HEF and NG + 15 % HEF). The results demonstrate that the NG + 10 % HEF and NG + 15 % HEF mixtures allow for a decrease of 1.84 % and 2.33 % in BSFC and an increase of 1.88 % and 2.38 % in BTE. Through the NG + 15 % HEF mixture, the engine achieved an energy efficiency of 34.15 % and an exergetic efficiency of 32.84 %. Additionally, the NG + 15 % HEF mixture reduces annual CO, CO2, and HC emissions by 9.52 %, 15.48 %, and 13.39 %, respectively. The addition of hydrogen positively impacts the engine's economic cost, allowing for a decrease of 1.56 % in the cost of useful work and a reduction of 3.32 % in the cost of exergy loss. In general, the proposed system for hydrogen production represents an alternative for utilizing the residual energy from exhaust gases, resulting in better performance parameters, reduced annual pollutant emissions, and lower economic costs.

Optimally integrated waste heat recovery through combined emerging thermal technologies: Modelling, optimization and assessment for onboard multi-energy systems

This paper investigates waste heat (WH) valorisation on maritime vessels from a systemic perspective. It aims to demonstrate how a set of innovative waste heat recovery (WHR) technologies can synergistically work together to valorise waste heat in multiple ways. It proposes and develops a dedicated techno-economic analysis framework and model, surpassing previous literature that focused on individual technologies or specific combinations. Employing a Mixed Integer Linear Programming (MILP) approach, this study evaluates the dynamic and flexible operation of the WHR system throughout the round-trip journey of a vessel. Identifying the most profitable WHR system layout, determining the capacity of technologies, optimising the interconnections between technologies, and establishing strategic WH dispatching are all among the key objectives of the study.An average-scale vessel with a 36 MW diesel engine, is selected for this study which involves a 17-day journey with multiple stops in Northern Europe. The vessel adequately represents the complexity of onboard energy systems in terms of types and variability of demands, as well as WH availability. The proposed WHR system, which is tailored for the selected vessel, integrates three active technologies: an isobaric expansion engine (IEE) to contribute to mechanical power demand, a sorption system for providing cooling, and an advanced Organic Rankine Cycle (ORC) for trigeneration of power, heating, and cooling. All technologies are supported by the passive WHR technology of Thermal Energy Storage (TES). The results show that deployment of the optimised WHR system onboard the selected vessel enhances energy efficiency by 5 to 7.5 percentage points and reduces fuel consumption by 13%. The study also explores economic key performance indicators (KPIs), such as the Internal Rate of Return (IRR) which is found at about 15%, clearly evidencing a compelling solution to ship owners. Additionally, the discussion includes a detailed analysis of the contribution of individual technologies in covering onboard demands, as well as their synergistic interactions.This work clarifies the role, value, and benefit of WHR technologies onboard, advancing the understanding from individual WH recovery interventions to a system-level approach. This is especially valuable in practice, considering its adaptability across various vessel types within the global fleet.

Thermo-economic feasibility study to utilize ORC technology for waste heat recovery from Indian nuclear power plants

A feasibility study is essential before installing a power generation system to recover waste heat from nuclear power plants, but not yet been done. Hence, nine possible waste heat locations of Indian nuclear power plants are identified and two feasible cases (case-1 and case-2) are deduced to use the organic Rankine cycle (ORC) as a bottoming cycle. Energy, exergy, economic and environmental performances are evaluated for feasible cases with three working fluids. Capital investment in alternator has been correlated based on market data and applied in economic analysis. The economic study is based on Net present value, Discounted payback period, Levelized cost of energy, Internal rate of return, Profit and per unit build-up cost of ORC to suggest whether the installation is worth to venture or not. The result shows that below 41 °C condenser temperature, case-2 based bottoming ORC should be the priority to install and at the availability of sufficient funds, both cases can be installed, which will cumulatively produce 486.2 kW of electricity from waste energy with a total of 201.14 thousand USD annual profit from the total capital investment of 723.74 thousand USD. In 40 years of the project's lifetime, a total of 1.317 million USD will be used if both cases are employed and the invested cost will be returned in 8.3 years.

CCUS-assisted electricity-chemical polygeneration system for decarburizing coal-fired power plant: Process integration and performance assessment

In the context of global carbon neutrality, carbon capture and storage (CCS) technology has become an important transition pathway to decarbonizing coal-fired power plants (CFPP). However, CCS technology has strict requirements for geological storage and the potential risk of CO2 leakage. Meanwhile, the deployment of the CCS technology in the CFPP could drastically reduce plant efficiency. To address the aforementioned issues, a novel carbon capture, utilization and storage (CCUS)-assisted electricity-chemical polygeneration process (i.e., ECPP) was proposed to produce electricity, liquid fuels, and high-calorie synthetic natural gas simultaneously. To reduce the efficiency loss caused by the consumption of internal steam and electricity, heat integration and Organic Rankine Cycle (ORC) technologies were adopted to fully recover the available waste heat and achieve the cascade utilization of the internal energy. Meanwhile, a detailed techno-economic assessment was conducted to further determine the benefits of the process integration. The results indicated that the application of heat integration and ORC technologies improves plant efficiency by 6 %. Moreover, it also reduces the cost of electricity and CO2 conversion cost by 17 and 15 %, respectively. In addition, compared with the traditional CFPPs retrofitted with CCS technology, the CO2 utilization and waste heat recovery technologies in ECPP enhance net electricity output and plant efficiency by 19 and 34 %, respectively. Therefore, the proposed CCUS-assisted ECPP achieves the efficient utilization of the waste CO2, and reduces the efficiency penalty for retrofitting the CFPPs. Overall, the proposed ECPP is an essential alternative for the retrofit of the existing CFPPs, and provides a feasible strategy for establishing a clean and sustainable power polygeneration system.

Comparative performance analysis of different hydrogen power composite cycles with waste heat recovery

ABSTRACT Hydrogen energy has been under close scrutiny by countries around the world. At present, the main technologies for utilizing hydrogen energy in transport power systems are hydrogen internal combustion engine (HICE) and proton exchange membrane fuel cell (PEMFC). Since both of them generate a large amount of waste heat, and waste heat recovery technology is one of the most promising means of utilizing waste heat to improve efficiency, this paper makes a comprehensive comparison of the two technologies in composite waste heat recovery (WHR) system in terms of modeled maximum efficiency, full operating condition efficiency and future predicted maximum efficiency. Based on the thermal efficiency analysis, the advantages, disadvantages, and development prospects of the two technologies in composite the WHR system are reevaluated. The results demonstrate that the efficiency of the HICE and PEMFC can be improved by 6.83% and 2.81%, with the use of WHR system, respectively. Under the full range of operating conditions, the HICE-WHR composite system has obvious efficiency advantage in middle-high load working condition, but PEMFC-WHR composite system has obvious efficiency advantage in low load working condition. Both of them will be very competitive and potential technology routes of hydrogen energy utilization for land transportation.

Research on Boiler Energy Saving Technology Based on Internet of Things Data

This paper proposes a heat demand prediction model that analyzes the heat behavior of heat users, and analyzes the heat behavior data of heat users through a clustering algorithm to predict their heat demand. This paper is based on the supply-demand balance strategy to reduce the heat loss during the transmission of heat medium, and then improve the energy-saving efficiency of the boiler. The traditional boiler energy-saving and consumption reduction method is to optimize the boiler combustion parameters, improve the fuel combustion efficiency and waste heat recovery technology through the Internet of Things and big data technology. The method of balancing the heat-using end with the load of the boiler at low usage frequency is seldom considered. Therefore, this paper predicts the heat demand of the heat-using end by analyzing its thermal behavior, and balances the heat demand and boiler heat supply under the condition of meeting the heat demand. Finally, through simulation experiments, the validity of the model is verified, and the trend and data can be well predicted in the short-term heat demand prediction.

The Development and Research of Waste Heat Recovery Technology

In the context of advancing societal and technological landscapes, the global escalation in energy demand has underscored the looming threat of dwindling energy resources. Over recent years, China has consistently showcased its commitment to assuming the role of a responsible major nation by actively advocating for green and low-carbon development. This commitment is tangibly reflected in a series of green initiatives that progressively prioritize and incentivize enterprises to partake in the recovery and utilization of waste heat. This paper offers a comprehensive review of extensively researched waste heat recovery technologies within China, elucidating their operational principles and highlighting contributions made by relevant scholars. Currently, waste heat utilization stands as a focal point for intensive research, with simultaneous benefits including heightened energy efficiency, resource conservation, and the mitigation of thermal energy wastage, thereby addressing environmental concerns. The implications of such advancements extend significantly to the enhancement of China's societal, ecological, and economic spheres.

Efficient harvesting of renewable evaporative energy from atmospheric air through hierarchical nano/microscale shaping of air-water interface

Renewable evaporative energy from atmospheric air is a recently emerged research field that demonstrates the great potential for significant energy savings in the air conditioning of buildings, data/big-data/integrated-big-data centers, agricultural storage facilities, and greenhouses. Here, we develop a method for an essential increase in the harvesting efficiency of renewable air evaporative energy by enhancing the water evaporation rate through the shaping of the air-water interface (AWI) by the menisci formed in superhydrophilic hierarchical surface nano/microstructures. Using this method, we achieve a 10-fold rise in the evaporation rate for the microscale AWI shaping. For the first time, we discover the superevaporation effect that provides an unprecedented 130-fold rise in the evaporation rate at the hierarchical nano/microscale AWI shaping. Furthermore, based on these findings, for the first time, we elaborate a novel material with an engineered AWI for a significant increase in the harvesting of renewable air evaporative energy in the dew point (Maisotsenko cycle) indirect evaporative air conditioning systems whose operation is fundamentally based on utilizing renewable air evaporative energy. The dew point cooling device fabricated using this novel material shows significantly superior cooling performance, validating the substantially enhanced harvesting of the air's evaporative energy. Our findings can essentially advance the emerging field of renewable air evaporative energy and, besides the air conditioning technology, can provide significant efficiency enhancements in water purification/desalination, thermal management, gas turbine power generation, and waste heat recovery technologies.

Research on the coal saving and emission reduction potential of advanced technologies in China's iron and steel industry

The coal-based energy consumption structure has led to high coal consumption and carbon emissions in China's iron and steel industry, and the task of coal saving and carbon reduction in the steel industry is difficult and urgent. The economic viability of various coal-saving and emission-reduction technologies, the extent of their coal-saving and emission-reduction potential, and the guidance on the adoption of advanced technologies are crucial issues that need to be addressed in the Chinese steel industry. This article employs the Energy-Production (E-P) analysis method and the Conservation Supply Curve (CSC) model incorporating coal consumption ratio coefficients to systematically analyze coal consumption and carbon dioxide emissions in the overall iron and steel industry and its sub-processes under different scenarios. It calculates the coal-saving emission reduction costs of 32 technologies, evaluates them comprehensively based on their coal-saving and emission-reduction potentials and cost-effectiveness, and categorizes them accordingly. According to the cost of coal saving and emission reduction as the demarcation point, a total of 19 technologies are cost-effective; according to the coal-saving emission reduction potential and cost division, 32 technologies are divided into 6 categories, among which 6 technologies such as sintering waste heat recovery technology can be used as key technologies for popularization and application. Seven technologies, such as efficient preheating technology of ladle, have high cost and low potential, which can be gradually eliminated or improved and upgraded. After the comprehensive promotion of the 32 technologies, the maximum coal saving potential is about 3.453 billion GJ, the CO2 emission reduction potential is 395 million tons, the total coal consumption of the steel industry can be reduced to about 13.904 billion GJ, and the carbon dioxide emissions can be reduced to 1.179 billion tons.