The intelligent retrofit of coal-fired power generation units is an inevitable choice for improving energy efficiency and promoting green industrial transformation. Based on practical requirements and engineering perspectives, this article designs the overall framework and key technologies for the intelligent retrofitting of wet flue gas desulfurization systems. First, the structural components of the intelligent control system (ICS) network framework are discussed. Next, based on the ICS framework, an optimized control strategy combining information-physical fusion models and advanced control algorithms is designed, as well as an optimized control strategy for the absorption tower pH value based on the direct energy balance (DEB) approach. Simultaneously, the information-physical fusion optimization results guide the analysis of the intelligent evaluation system. Using data twin technology and mechanism models, intelligent early warning and fault diagnosis for the system are achieved. By analyzing typical faults, an expert system is established, combined with data-driven techniques for real-time fault tracking. Finally, the article points out that a visualization-based human-machine interaction system is used for real-time display of desulfurization system indicators, constructing an integrated desulfurization system that combines ICS, digital twins, machine learning and visualization. This provides a basis for realizing a self-optimizing, self-learning, self-recovering, self-organizing and self-adaptive intelligent desulfurization system.

Zhundong has large coal reserves and low mining costs, making it the most economical fuel in the Xinjiang Zhundong region. However, Zhundong coal has strong slagging and fouling properties, which seriously restricts the safe and stable operation of boilers. Boilers in the Zhundong region usually require burning at least 20% low alkali coal, the low reserves and high prices of low alkali coal seriously constrain the cost reduction of power plants. In order to promote cost reduction, an experimental study on burning high ratio of Zhundong high alkali coal was conducted on the 350 MW unit boiler of Wucaiwan Power Plant. A collaborative optimization strategy was adopted to prevent and control slag and contamination on the heating surface of the boiler. This included adding kaolin to coal to regulate the composition of coal ash, and deeply optimizing the operating parameters of the pulverization system, combustion system, and soot blowing system. The test results show that the collaborative optimization strategy has solved the long-standing problems of large-scale slag flow on the water-cooled wall, clogging of the burner nozzle, and severe fouling of the convective heating surface of this type of boiler. The safety and load capacity of the boiler operation have been greatly improved, and the coal structure can be lastingly maintained as 92.5% Zhundong high alkali coal and 7.5% kaolin, with significant safety and economic benefits.

The proposal of the "dual carbon" has brought profound changes to the development of China's energy and power industry. As the leading enterprises in China's power industry, the five major power generation groups should play a demonstration and leading role, analyze and evaluate their low-carbon transformation achievements have important significance for the power generation industry to achieve the "dual carbon" goal as scheduled. This article uses the entropy weight TOPSIS method to conduct empirical research and analysis on the indicator data of the five major power generation groups in China from 2017 to 2021. The empirical results show that from a vertical dimension, it is found that the low-carbon transformation of the five power generation groups has achieved good results in 2017 to 2021, and the low-carbon transformation performance of each power generation group has shown an increasing trend year by year. This indicates the implementation of policies related to structural adjustment, emission reduction, and re transformation of the five power generation groups, achieved positive and significant results; from a horizontal perspective, the rankings of the five major power generation groups have been constantly changing from 2017 to 2021, indicating that each power generation group has made varying degrees of progress in low-carbon transformation.

In order to explore the way of high efficiency and low nitrogen combustion in oxy-fuel combustion, the experimental study on oxy-fuel staged combustion characteristics of Shenfu bituminous coal and Yunnan inferior bituminous coal was carried out on the down-draft furnace of Dongfang Boiler Test Center, and the burnout characteristics and nitrogen oxide emission characteristics of two kinds of coal under oxy-fuel staged combustion conditions were explored. The experimental results show that under the condition of oxy-fuel combustion, the combustion efficiency of Shenfu bituminous coal can reach more than 99%, and the NO_x emission concentration in flue gas can be controlled within 19.10 mg/MJ by using over-fire air staged combustion and reasonable control of oxygen staged feeding. The combustion efficiency of Yunnan inferior bituminous coal is slightly lower due to the delay of ignition and the long enough residence time required for burnout. However, the combustion efficiency can reach more than 90 % with reasonable oxygen classification, and the NO_x emission concentration in flue gas can be controlled within 16.83 mg/MJ. The effect of furnace temperature of oxy-fuel combustion on the cumulative formation and release curve of NO_x is consistent with that of air combustion. The higher the furnace temperature, the faster the heating rate of pulverized coal particles. The higher combustion efficiency and lower NO_x emission concentration can be found by adopting oxy-fuel staged combustion and reasonably controlling the timing and position of oxygen staged injection, so as to achieve high efficiency and low NO_x emission of oxy-fuel combustion.

In order to solve the problems of high pollutant emission mass concentration, low energy utilization rate and high initial investment cost of conventional waste disposal power station, combined with the green transformation development needs of coal-fired power station. This paper proposes the technical ideas of coal-fired boiler station coupled with waste. A 30 t/d coal-fired boiler station coupled waste was built to analyze and study the impact of system operation on the efficiency of coal-fired power station, pollutant emissions and energy efficiency of waste disposal. And this paper uses three coupling methods of hot air, flue gas and steam water to achieve efficient and clean disposal waste on large coal-fired power station. The results show the three coupling methods are completely feasible to achieve efficient and clean disposal waste. The coupling of hot air can improve the effect of disposal waste and reduce the carbon content of fly ash and slag; the coupling of flue gas can ensure conventional pollutants such as SO₂, NO_x and dust reach the emission level of coal-fired power station without increasing the emission of dioxins. The coupling of steam water can improve the energy efficiency of disposal waste. This technology provides new technical ideas for the disposal of organic solid waste and has a broad application prospect.

The alkali metals released during combustion of high alkali coals can easily lead to fouling and slagging of the heated surfaces of the furnace, affecting the safety of boiler operation, and it is significant to carry out the research of the slagging trend prediction. In this paper, a system for dynamic prediction of slagging trends in the furnace was developed by combining the slagging trend discrimination method based on ash composition analysis with flame emission spectroscopy. Firstly, a flame emission spectroscopy system was installed on the boiler to measure the gas phase alkali metal concentration in the furnace, and then a slagging trends test was carried out in the furnace exit area to obtain the deposition trend of the ash samples. Finally, a dynamic predictive system for predicting slagging in the furnace was developed and applied to the boiler by combining the slagging discriminating trends based on ash composition analysis of different coal samples and online monitoring of gas-phase Na concentrations, which can reflect the monitoring results of each parameter under the current combustion conditions in real-time, indicate the slagging trend in the current combustion state, thus enabling combustion adjustment instructions to prevent severe slagging.

In order to study the feasibility and economic benefits of implementing carbon capture, utilization and storage (CCUS) technology in coal-fired power plants, based on the thermal power installation planning and generation data provided by a northwestern province, three different CCUS transformation schemes in 2023, 2025 and 2030 were proposed, and their economic analysis was conducted. It is found that the first plan needs investment of 1 220.293 billion yuan, which translates into an increase of about 0.076 3 yuan /(kW·h); the second plan needs investment of 1 123.19 billion yuan, which translates into an increase of about 0.076 9 yuan /(kW·h); the third plan needs investment of 860.12 billion yuan, which translates into an increase of about 0.069 0 yuan /(kW·h). Aiming at the high cost of CCUS transformation scheme, a technical route combining CCUS and methane dry reforming was proposed, and the captured CO₂ was used to produce syngas. It was found that the expenditure and income of 1 t CO₂ due to the consumption of natural gas to produce syngas were 1 520.7 yuan and 3 247.2 yuan respectively. Comprehensive carbon capture system analysis options two and three can achieve zero-cost decarbonization.

Chemical absorption method is an important way to apply and treat CO₂ from coal-fired power plants on a large scale, however, the traditional chemical absorption method with monoethanolamine as absorbent has been limited in its wide application because of the high energy consumption. In this paper, the research progress on the improvement of CO₂ capture process is reviewed with the new CO₂ capture solvents, the improvement of absorption process including intermediate cooling of absorber and solvent recirculation, Flash compression and regeneration process of steam/pentane direct purging are summarized, it was also pointed out that pilot-scale verification of new solvents based on the actual composition of flue gas, and the study of capture solvent degradation properties and volatile organic compound treatment processes were the research and development directions of carbon capture research, it points the way for future research on industrial carbon capture.

In order to use the market mechanism to reduce carbon dioxide emission and promote green low-carbon transition, countries around the world have successively built carbon emission trading markets. Carbon dioxide emission monitoring technology is the main technical method to achieve accurate carbon emission measurement. It is an important technical support to assist the carbon emission accounting system. This paper focuses on the analysis of the current situation of carbon dioxide emission monitoring and accounting in the power generation industry, and introduces the carbon dioxide emission monitoring methods in the power generation industry in detail, including emission factor based method, online monitoring method, carbon balance method, soft sensing method, and satellite monitoring method. In view of these monitoring methods, this paper systematically reviews the researches of carbon dioxide emission monitoring methods in the world, expounds the advantages and disadvantages of the monitoring methods, compares the methods from accuracy, timeliness, reliability and monitoring cost, and provides reliable technical solutions for carbon dioxide emission monitoring in the power generation industry. Finally, we make an outlook on future research directions and practical applications.

Rapid and accurate measurement of the calorific value of incoming coal is the essential to provide guidance for the economic and safe operation of power plants. However, coal has complex components, and the calorific value is correlated with elemental composition and molecular structure, it is difficult to measure coal calorific value quickly and accurately by a single analytical technique. Based on laser-induced breakdown spectroscopy (LIBS) and near-infrared reflectance spectroscopy (NIRS), a method is proposed to detect the calorific value of incoming coal by combining two techniques. The LIBS and NIRS spectral signals of the coal on the conveyor belt are collected simultaneously. Fusion of two spectral information after data pre-processing, coupled with partial least squares (PLS) modeling method to quantify coal calorific value. This method is used in a coal sample measurement system built by lab, it is reached that the coefficient of determination of the calibration set was 0.98, and the root mean square error of the prediction set was 0.37 MJ/kg, with an average absolute error of 0.26 MJ/kg and an average relative error of 1.09%. The results show that the proposed method of simultaneous acquisition of LIBS and NIRS signals can measure coal calorific value rapidly and accurately.