Coal-fired Boilers Research Articles

Emission and distribution characteristics of PCDD/Fs during the co-processing of various solid wastes in coal-fired boilers in China

The advancement of co-processing solid wastes in coal-fired boilers is significant for waste recycling and contributes to the sustainable development of the coal-fired power industry. However, concerns over the emission of dioxins during co-processing have prompted a comprehensive investigation into the dioxin emission properties. In this study, the PCDD/F emission concentrations of seven coal-fired boilers, including three pulverized coal boilers and four circulating fluidized bed boilers were examined. The results indicate that co-processing solid wastes in coal-fired boilers did not lead to an increase in the mass concentration of dioxins in either the flue gas or solid samples, and the international toxic equivalents (I-TEQ) of dioxins in the flue gas complied with prevailing emission standards (0.1 ng I-TEQ/Nm3) in China, proving that coal-fired boilers co-processing would not raise the emission risk of dioxins. The types of waste during co-processing had minimal effect on the I-TEQ of dioxins. A significant proportion of PCDD/Fs was observed in the ash samples, while only 13.0–25.7% and 0.7–6.8% of dioxins were distributed in the boiler slag and the flue gas, respectively. The emission factor of dioxins under the blank conditions ranged from 0.009 to 0.327 ng I-TEQ/kg-coal, while it ranged from 0.015 to 0.129 ng I-TEQ/kg-(coal+waste) under the co-processing conditions. The reduction of emission factor under co-processing condition could be attributed to the significant decrease of dioxins I-TEQ.

Analysing the Techno-Economic Viability of Different Solar Heating Systems in South African Beverage Plants

With ongoing real-term reductions in the cost of renewable energy technologies, opportunities to reduce carbon emissions within industry have improved. While the South African industrial sector has been investing in photovoltaics to meet electricity requirements, little has been done to replace fossil fuels used for the generation of process heat, representing two-thirds of the energy consumed. While previous studies have demonstrated the benefits and limitations of solar thermal (ST) energy solutions for industrial applications, recent developments in high-temperature heat pumps (HTHP) offer opportunities for novel configurations, including the use of renewable energy like photovoltaics (PV). This study compares the techno-economic benefits of solar thermal energy systems with PV-supported HTHP systems within the South African beverage sector. After a general consideration, simulation calculations are presented for selected applications. The cost of heat is determined for PV-heat pump systems operating on a stand-alone basis and with heat storage. The study finds that the levelised cost of heat of US$0.050-0.073/kWhth is at least twice that of coal-fired steam boilers. The study, therefore, calls for further work on optimising systems minimising steam requirements, and thereby improving the economics of heat pumps and for a coordinated effort to support the development and financing of high-temperature heat pumps for industrial applications.

Numerical Study on Combustion Characteristics of Biogas Cocombustion in a 300MW Coal-Fired Boiler Furnace.

To further explore cocombustion technology with biogas and coal, a series of numerical simulations have been carried out to analyze the effects of the cocombustion ratio ξ, height of biogas nozzle HGN, and tilt angle of burner θBN on combustion characteristics in a 300 MW four-corner tangential boiler furnace. Three types of biogas are gasified from straw, sawdust, and raw wood when air serves as the gasification agent. The velocity field, temperature field, and NO emissions have been comprehensively analyzed when the values of ξ, HGN, and θBN range, respectively, from 0.02 to 0.12, from 17.3 to 20.3 m, and from -15° to +15°. Results showed that the NO concentration at the furnace outlet monotonously decreased with ξ. The injection of biogas reduces both the peak temperature of the entire boiler furnace and the NO concentration at the furnace outlet. The NO emission concentration decreases with the increased ξ value for all types of biogases. The cocombustion with sawdust biogas indicates the least NO emission at a fixed cocombustion ratio. Furthermore, reducing the furnace height at HGN = 17.3 m or titling down the burner at θBN = -15° contributed to a greater NO concentration at the furnace outlet.

A comprehensive examination of temporal-seasonal variations of PM1.0 and PM2.5 in taiwan before and during the COVID-19 lockdown

COVID-19 has been a significant global concern due to its contagious nature. In May 2021, Taiwan experienced a severe outbreak, leading the government to enforce strict Pandemic Alert Level 3 restrictions in order to curtail its spread. Although previous studies in Taiwan have examined the effects of these measures on air quality, further research is required to compare different time periods and assess the health implications of reducing particulate matter during the Level 3 lockdown. Herein, we analyzed the mass concentrations, chemical compositions, seasonal variations, sources, and potential health risks of PM1.0 and PM2.5 in Central Taiwan before and during the Level 3 lockdown. As a result, coal-fired boilers (47%) and traffic emissions (53%) were identified as the predominant sources of polycyclic aromatic hydrocarbons (PAHs) in PM1.0, while in PM2.5, the dominant sources of PAHs were coal-fired boilers (28%), traffic emissions (50%), and iron and steel sinter plants (22.1%). Before the pandemic, a greater value of 20.9 ± 6.92 μg/m3 was observed for PM2.5, which decreased to 15.3 ± 2.51 μg/m3 during the pandemic due to a reduction in industrial and anthropogenic emissions. Additionally, prior to the pandemic, PM1.0 had a contribution rate of 79% to PM2.5, which changed to 89% during the pandemic. Similarly, BaPeq values in PM2.5 exhibited a comparable trend, with PM1.0 contributing 86% and 65% respectively. In both periods, the OC/EC ratios for PM1.0 and PM2.5 were above 2, due to secondary organic compounds. The incremental lifetime cancer risk (ILCR) of PAHs in PM2.5 decreased by 4.03 × 10-5 during the pandemic, with PM1.0 contributing 73% due to reduced anthropogenic activities.

Studying the Effect of Fireball Position in the Furnace on the Coal Fired Boiler’s Operation Mode

Studying the Effect of Fireball Position in the Furnace on the Coal Fired Boiler’s Operation Mode

Hydrodynamic force and torque models for cylindrical particles in a wide range of aspect ratios

During the pneumatic conveyance of biomass in a coal-fired power station boiler, biomass particles have cylindrical shapes with different aspect ratios. They move through the fluid at any angle and rotate strongly. However, highly accurate and general models of the drag, lift, and torque coefficients (CD, CL, and CT) for biomass particles in a wide range of aspect ratios, especially the CT model and the high aspect ratios, are currently lacking. This paper presents detailed direct numerical simulations of the flow around cylindrical cylinders with varying aspect ratios (6 ≤ AR ≤ 22), Reynolds numbers (100 ≤ Re ≤ 2000), and angles of incidence (0° ≤ θ ≤ 90°). The simulation was conducted using the OpenFOAM solver with the body-fitted mesh method. The flow characteristics and force coefficients of cylindrical particles with different AR were systematically analyzed. New functional correlations between CD, CL, and CT and AR, Re, and θ values were established. The mean squared errors for CD, CL, and CT were 8.8 × 10–2, 2.4 × 10–2, and 4.7 × 10–2, with average relative errors of 5.8%, 3.5%, and 8.17%, respectively. A comparison of the results with other experimental and simulation data in previous literatures showed that the new CD and CL models have considerable higher predictive ability. The generality of the new CD model expanding to low ARs of 1.5 and 3 is verified finally. The new force and torque models are expected to improve the accuracy of Eulerian–Lagrangian simulations of various cylindrical particle-laden flows in the utility of biomass energy.

Study on the Co-combustion characteristics and synergistic effect of semi-coke and dust coal produced from biomass briquette in fluidized bed gasification

Biomass briquette semi-coke (BFSC) is one of the byproducts of biomass gasification. It is difficult to reuse due to its inadequate carbonization, unsatisfactory pore structure, and surface properties. Co-combustion of BFSC with coal-fired boilers can be a cost-effective usage of biomass gasification semi-coke while also improving dust coal's combustion characteristics. However, research on the optimal blending ratio, co-combustion properties, and synergistic effects of BFSC and dust coal is lacking. This study conducted experimental and theoretical research on the co-combustion and reaction kinetic characteristics of BFSC and dust coal with a 0.3 MW pilot experimental system. The findings indicate that during co-combustion, sawdust semi-coke (SC), eucalyptus bark semi-coke (EBC), rice husk semi-coke (RHC), and corn straw semi-coke (CSC) exhibit favorable synergistic effects. At a 25 % blending ratio, the corresponding synergistic parameter indexes (SPIs) were 1.313, 1.053, 1.001, and 1.042. Adding EBC and SC may significantly promote the combustion of dust coal and make it enter the combustion stage sooner, improving combustion stability. When 25 % RHC or CSC is co-combusted, the activation energy predicted by the kinetic control equations is 17 kJ/mol and 5 kJ/mol lower than theoretical values, with a relative error of less than 3 %. The annual EBC output from a 1-ton biomass boiler may replace roughly 706 tons of normal coal, lowering CO2 emissions by approximately 634 tons and producing a direct economic gain of $33300. Therefore, BFSC is a low-carbon and low-cost coal boiler fuel with great potential for large-scale industrial applications.

Flow and Heat Transfer Characteristics of Superheater Tube of a Pulverized Coal-Fired Boiler Using Conjugate Heat Transfer Modeling

This study is a numerical study to predict the temperature of the heat exchange tubes inside the pulverized coal-fired boiler through the conjugate heat transfer analysis. Due to the aspect ratio and number of tubes inside the pulverized coal-fired boiler, actual tube modeling analysis has rarely been conducted. Most of the research has been conducted through the porous media method, resulting in limited information on the temperature distribution of each tube. However, for the development of a digital twin model for improving the performance of the boiler and reducing maintenance costs, information on the local temperature of the tubes is required. In this study, all the tubes inside the boiler were modeled, and conjugate heat transfer analysis was performed to confirm the local temperature distribution. For this purpose, the analysis was conducted using Fluent 2020 r2, and the analysis model was constructed using more than 300 million structured grids. The calculation was performed considering conjugate heat transfer in the pulverized coal-fired boiler, heat exchange by steam inside the tubes, and conductive heat transfer of the tubes. As a result, it was confirmed that there is a significant deviation in the local temperature for each tube position. Furthermore, the maximum temperature of the PrSH tube ranges widely, between 492 and 532 degrees, depending on the tube’s position. It was observed that the point of the highest temperature inside the tubes also varies for each tube due to the flow of external combustion gas. Based on these results, it is expected that strategic approaches to boiler design and maintenance can be achieved. Furthermore, it is anticipated to contribute to the high efficiency of power facilities by being utilized as basic data for the development of a digital twin model for the boiler.

Detailed kinetics modeling of sulfur species evolution in alternating reducing/oxidizing atmosphere

Under conditions of deep load fluctuation, the furnace of a coal-fired boiler experiences alternating reduction/oxidation atmospheres, which directly impact the evolution of sulfur species. Building upon our previous mechanism (Model I), this study specifically considered the influence of alternating atmospheres and proposed a comprehensive reaction model (Model II), incorporating 8 additional elementary reactions. The relative error in predicting the concentration distribution of sulfur species was reduced from 18% (Model I) to 13% (Model II). In the alternating atmospheres, the predominant sulfur species remained as SO2 and H2S. Sensitivity analysis revealed that S, SH, SO, HSO, and HOSO were the critical free radicals. The new supplementary reactions (118) H2S + M = SH + H + M and (116) H2S + O2=HSO + OH played a significant role in the generation and consumption of H2S and SO2. Rate of production analysis demonstrated that the alternating atmosphere impacted the production and consumption primary free radicals like O/H/OH, thus potentially causing changes of S, SH, SO, HSO, and HOSO; moreover, it introduced new reaction pathways for SH and SO. Finally, a simplified reaction pathway for the sulfur species evolution was proposed. This study seeks to provide insights into the sulfur species evolution under the peak regulation conditions in coal-fired boilers.

Prediction of Energy Consumption in a Coal-Fired Boiler Based on MIV-ISAO-LSSVM

Aiming at the problem that the energy consumption of the boiler system varies greatly under the flexible peaking requirements of coal-fired units, an energy consumption prediction model for the boiler system is established based on a Least-Squares Support Vector Machine (LSSVM). First, the Mean Impact Value (MIV) algorithm is used to simplify the input characteristics of the model and determine the key operating parameters that affect energy consumption. Secondly, the Snow Ablation Optimizer (SAO) with tent map, adaptive t-distribution, and the opposites learning mechanism is introduced to determine the parameters in the prediction model. On this basis, based on the operation data of an ultra-supercritical coal-fired unit in Xinjiang, China, the boiler energy consumption dataset under variable load is established based on the theory of fuel specific consumption. The proposed prediction model is used to predict and analyze the boiler energy consumption, and a comparison is made with other common prediction methods. The results show that compared with the LSSVM, BP, and ELM prediction models, the average Relative Root Mean Squared Errors (aRRMSE) of the LSSVM model using ISAO are reduced by 2.13%, 18.12%, and 40.3%, respectively. The prediction model established in this paper has good accuracy. It can predict the energy consumption distribution of the boiler system of the ultra-supercritical coal-fired unit under variable load more accurately.

Air quality and health benefits for different heating decarbonization pathways in China

The urgent need for decarbonization in China's heating system, comprised of approximately one hundred thousand boilers, is imperative to meet climate and clean air objectives. To formulate national and regional strategies, we developed an integrated model framework that combines a facility-level emission inventory, the Community Multiscale Air Quality (CMAQ) model, and the Global Exposure Mortality Model (GEMM). We then explore the air quality and health benefits of alternative heating decarbonization pathways, including the retirement of coal-fired industrial boilers (CFIBs) for replacement with grid-bound heat supply systems, coal-to-gas conversion, and coal-to-biomass conversion. The gas replacement pathway shows the greatest potential for reducing PM2.5 concentration by 2.8 (2.3–3.4) μg/m3 by 2060, avoiding 23,100 (19,600–26,500) premature deaths. In comparison, the biomass replacement pathway offers slightly lower environmental and health benefits, but is likely to reduce costs by approximately two-thirds. Provincially, optimal pathways vary – Xinjiang, Sichuan, and Chongqing favor coal-to-gas conversion, while Shandong, Henan, Hebei, Inner Mongolia, and Shanxi show promise in CFIBs retirement. Henan leads in environmental and health benefits. Liaoning, Heilongjiang, and Jilin, rich in biomass resources, present opportunities for coal-to-biomass conversion.

A novel data center air conditioner and its application scheme balancing high-efficiency cooling and waste heat recovery: Environmental and economic analysis

Data centers require continuous cooling throughout the year and produce a large amount of low-grade waste heat. How to fully utilize the waste heat while ensuring the efficiency of air conditioning is a problem that needs to be addressed. In this paper, a data center air conditioning with heat recovery function was constructed, and the application scheme of the novel system that considers both high-efficiency cooling and waste heat recovery was proposed. The feasibility analysis was conducted at a data center in Shenyang, with the heat pipe/vapor compression high-efficiency system for cooling and the coal-fired boiler for heating as the comparison scheme. The results show that although adding heat recovery function realizes the utilization of waste heat in data centers, it also increases the energy consumption of the system. The centralized application scheme composed of a single large system reduces annual carbon emissions by 0.9 % and increases operating costs by 12.6 %. The distributed application scheme composed of multiple small systems reduces annual carbon emissions by 14.6 % and reduces operating costs by 3.5 %.

Experimental study on the effects of ammonia cofiring ratio and injection mode on the NOx emission characteristics of ammonia-coal cofiring

Ammonia (NH3) cofiring is a promising approach to reduce the CO2 emissions from coal-fired power plants. However, the potential drastic increase of NOx emissions may inhibit the wide implementation of NH3 cofiring. To explore the potential NOx control strategies, the effects of NH3 cofiring ratio (RNH3), NH3 injection mode and overfire air (OFA) rates on the NOx emission characteristics of NH3/coal cofiring are studied in a test furnace that allow for flexible control of the injection positions and combustion environment of NH3. The results show that when NH3 is injected with coal stream (top mixing mode), the NOx emissions increase and then decrease with the increase of RNH3 under all OFA rates. However, when NH3 is fed through the side port of furnace separately (side mixing mode), the NOx emissions exhibit distinct trends under different OFA rates. Under lower OFA rates, the NOx emissions show monotonical decrease with the increase of RNH3, while under higher OFA rates the NOx emissions first decrease and then increase with the increase of RNH3. Consequently, higher OFA rates could produce higher NOx emissions than lower OFA rates. This indicates that air-staging is not always effective in the NOx reduction of NH3 cofiring. Thus, although the side mixing mode of NH3 cofiring exhibits overall better performance in NOx control, caution is needed to accommodate the OFA rate with NH3 cofiring ratio. Although a variety of trends of NOx emissions were observed in this study, the results demonstrate that all these trends are in fact governed by the same mechanism – the competition between the NO-formation and NO-reduction reactions of NH3 in the varying O2 environment in the furnace. By creating appropriate O2 environment in the furnace, the NOx emissions of NH3/coal cofiring could be substantially lower than that of pure coal combustion. The findings of these paper are instrumental in the design and operation of NH3 cofiring system in full scale coal-fired boilers to achieve effective NOx control.

Ignition behavior of a mixture of brown coal and biomass during the movement of fine particles in a hot air flow

The combustion of brown coal, biomass and their mixtures was studied experimentally and analytically. The experimental research was conducted using a laboratory setup that reproduced the conditions of combustion of pulverized solid fuel in a boiler furnace. Thermogravimetric analysis was employed as part of the analytical study to determine the key characteristics of combustion of solid fuels, such as temperatures at which the ignition and burnout occur, as well as the combustion index. Scanning electron microscopy was utilized to analyze the surfaces of coal and wood particles to detect pores, cracks and channels. To determine the tendency of the solid fuel mixture to slag heat exchangers in boiler furnaces, the ash residue characteristics (iron oxide deposits, active alkali, calcium sulfate compounds) were obtained. Biomass is more reactive than brown coal. Its ignition delay times at 500 °C and 750 °C are 57 % and 25 % lower, respectively, than those for coal. The higher the biomass content in the solid fuel mixture, the lower the ignition delay time. The heating source temperature at which the coal/biomass fuel mixture ignites corresponds to the temperature at which biomass ignites. With a larger proportion of biomass, the temperature during the fuel mixture combustion goes down, while the combustion index increases. On the basis of the findings of the conducted research, optimal proportions of solid fuel components were found (80 % brown coal, 20 % biomass). Also, fuel preparation and feeding systems for pulverized fuel combustion and fluidized bed combustion of optimal fuel mixtures in a coal-fired boiler furnace were proposed.

Energy, exergy, economic, and environmental analysis of a high-temperature heat pump steam system

Industrial steam is widely recognized as a valuable form of heat currency, possessing considerable social and economic significance. As the industry shifts to low carbon emissions, there is an urgent need to reduce CO2 emissions from industrial steam generation. The analysis of a high-temperature heat pump steam system (HTHPSS), which recovers industrial waste heat to produce high-temperature steam at 170 °C, includes evaluations of its energy, exergy, economic, and environmental (4E) to determine whether it can replace a coal-fired boiler. The economic analysis considered the recovery value of waste heat and the effect of CO2 trading prices. Optimization calculations were performed to investigate changes in the waste heat temperature and condenser outlet temperature. The study also offers recommendations for operational conditions and optimization strategies for the HTHPSS. The results indicate a positive correlation between the system coefficient of performance (COP) and the waste heat utilization rate with waste heat temperature and condenser outlet temperature. The maximum COP value is 2.73. The total exergy efficiency initially increases and then decreases as waste heat temperature increases. It also decreases as the condenser outlet temperature increases, reaching a peak value of 43.26 %. The waste heat temperature needs to be at least 59 °C to generate a net profit, with a corresponding payback period (PBP) of 4.40 years. The minimum PBP is 0.03 years, independent of waste heat temperature. The annual emission reduction increases as waste heat temperature increases and decreases as condenser outlet temperature increases. These results indicate that a HTHPSS could replace a coal-fired boiler and offer guidance for design optimization.

Investigation of Slagging Condition in a Zhundong Coal-Fired Boiler via In Situ Optical Measurement of Gaseous Sodium.

In this study, a portable spectral analysis instrument based on spontaneous emission spectroscopy (SES) was developed for the in situ, non-intrusive, and quantitative measurement of gaseous Na inside ZD coal-fired boilers, which is mainly applied for predicting slagging in furnaces. This technology is needed urgently because the problem of fouling and slagging caused by high alkali metals in ZD coal restricts the rational utilization of this coal. The relative extended uncertainty for the measurement of gaseous Na concentration is Urel = 10%, k = 2, which indicates that measurement data are reliable under working conditions. It was found that there is a clear linear relationship between the concentration of gaseous Na and fouling in high-alkali coal boilers. Therefore, a fast and efficient method for predicting the slagging and fouling of high-alkali coal boilers can be established by using this in situ online real-time optical measurement.

Study on radiation characteristics of coal fired boiler changing with burnout rate

The burnout rate is an important parameter in the combustion of pulverized coal. During the process of pulverized coal burnout, its radiation characteristics and the entire coal-fired boiler vary with the burnout rate, which is a very complex process and current research is not clear enough. This study proposes a new single particle pulverized coal burnout model, which incorporates pore volume correction to fit the density ratio and diameter ratio of multiple coal types with varying burnout rates as the theoretical basis. Using Mie theory, Jiaozuo coal particles are calculated average absorption and scattering efficiency in the band of 0.39 ∼ 16 μm, which is used as the basis for correcting particle emissivity and scattering factor. Then, through user defined function (UDF) in the simulation software, the particle radiation characteristics are modified from the original constants of 0.9 and 0.6 to linear and polynomial models that vary with the burnout rate. Not only do the spatial distribution rules of the coal-fired boilers radiation characteristics with the burnout rate of the furnace be obtained, but also the temperature distribution of the furnace under different particle radiation characteristics models is compared. The results show that the pulverized coal burnout model is consistent with the experimental results in literatures. High burnout rate corresponds to low mass concentration of furnace particles, and low absorption and scattering coefficients. Using the above model to calculate the particle emissivity and scattering factor that vary with the burnout rate, after UDF embedding, the error between the simulation results and the on-site cross-sectional temperature and thermal imaging detection decreases from 4.81 % to 2.59 %, reflecting the high accuracy and rationality of the burnout model and particle radiation characteristic correction method.

Influence of secondary air blade angle and oxygen-rich combustion characteristics of an improved Babcock swirl burner

Innovations in research methods and stable combustion technologies were urgent to enhance flexibility in faulty coal-fired boiler. Focusing boiler start-stop processes was vital for effective peak shaving in power plants. The integration of enriched oxygen stable combustion with swirling techniques showed promise in improving low-load performance. In the cold single–phase experiment, the influence of secondary blade angle on the flow field of an improved Babcock burner was observed. Industrial experiments were conducted on a 700 MW boiler, exclusively implementing the improved burners in the lower layer of the boiler front wall. Stable annular recirculation zones were observed at the burner outlet with blade angles of 30°, 45°, 60°, and 75° for the secondary air. Increasing the blade angle expanded the recirculation zone length and decreased the gas net flow ratio. The angle, between 45° and 60°, facilitated air mixing and protected against outlet slagging and high-temperature corrosion. During cold start–up process of the boiler, supplying 0 kg·s−1 of pure oxygen to a single improved burner increased the flue gas temperature by about 50 °C within 0.4 m of the primary air duct outlet. Increasing the oxygen flow rate to 0.2456 kg·s−1 steadily raised the flue gas temperature at 405 MW. The gas temperature in the burner central region was generally lower than the secondary air zone, resulting in a longer ignition distance for the pulverized coal. Higher oxygen levels intensified the heating rate and reduced the ignition distance in the central region.

A dynamic modeling method using channel-selection convolutional neural network: A case study of NOx emission

A novel channel-selection convolutional neural network (CS-CNN) is proposed to predict NOx emission from coal-fired boilers under steady-state and transient load conditions. First, a new channel-selection convolutional layer (CS-CL) is presented to replace regular convolutional layer (RCL). The CS-CL evaluates the channel importance of the input variables, selects the Top-C important channels and releases the hyperparameters of the remaining low-importance channels, thus contributing to maximize the utilization of the parameter resources of the model. The advantages of using CS-CLs are the preservation of the great majority of manipulated variables involved in combustion control among the input variables and the prevention of the model overfitting problem due to the redundancy of input variables. Second, a sliding window-based preprocessing method is applied to the historical data of the boiler which is divided into four-dimensional (4D) tensors. Then, comparative tests are performed on long short-term memory (LSTM) model, baseline CNN and CS-CNN using the historical data of a 670 MW boiler. The results of tests showed that CS-CNN has higher prediction performance. Finally, in order to increase the interpretability of the deep learning black box model, this study analyzes the working mechanism of the CS-CNN through ablation analysis and visualization of model parameters.

Methanol-based fuel boiler: Design, process, emission, energy consumption, and techno-economic analysis

Methanol-based alternative energy sources are critical to maintaining energy security, reducing the need for oil imports, and safeguarding the environment in China. However, the use of methanol-based fuels in the field of thermal combustion has not been thoroughly investigated. Therefore, an evaluation of the costs, emissions, and usage of methanol boilers is necessary. The study finds that methanol heaters and air source heat pumps have comparable annual cost values. Methanol heating furnaces emit the least amount of NOx and produce no SO2. After the refurbishment, the boiler's emissions and energy consumption have significantly decreased upon conversion of coal-fired steam boilers to methanol-based fuel hot water boilers. Nevertheless, the economy has also somewhat declined. Additionally, 5499 tce (standard coal) less energy will be used during the heating season, and 1.8 million CNY less will be spent on dust removal and desulfurization. Unfortunately, the economic benefits of methanol are only apparent when the cost of methanol fuel is less than 1900 CNY/t. The research presented in this paper provides an essential technological foundation for the development of methanol-fueled fuel burners and for the renovation of small and medium-sized coal-fired boilers.