RESEARCH INTERESTS

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Air pollution emission control technology

Multi-pollutant (PM, NOx, SVOC) collaborative reduction technology

The mechanism of forced phase change to suppress ultrafine particles and SVOC emissions is proposed.The original intention of this study was to treat acidic flue gas with front-end water washing equipment and reduce the corrosion of various back-end pollution prevention equipment. It designed supporting units such as quenching, washing, cyclone water removal, activated carbon adsorption, and bag dust collection to force CPM precursors to The intermediate term of the composite washing unit is converted to form FPM. At the same time, the operating environment of the washing unit is controlled in the dioxin resynthesis temperature range (400–200°C), and all dioxin that may be synthesized after combustion is concentrated in the granular phase of the water washing unit. This study was successfulAchieve system removal efficiencies of 98.1% CPM, 99.0% FPM2.5 and 99.9 dioxin, but the wash water sediments with high dioxin concentration need to be recycled. The system significantly extends the material life of the filter unit, reduces the risk of pollutant penetration and improves equipment corrosion, thereby reducing operating costs and achieving ultra-low emissions, published inJ. Hazard. Mater..

Dioxins have different effects on human respiratory deposition toxicity based on different particle sizes.Although dioxin can be effectively removed and controlled within the scope of regulations through the current BACT, it has been revealed that the deposition of particles of different particle sizes in the respiratory system is significantly different. Therefore, micron-level particles treated with new air pollution prevention and control technologies have been explored. Based on the particle size distribution of dioxin, it was found that the mass concentration of dioxin in particulate matter is between coarse and fine particles, and the sensitivity is not the same due to the influence of particle mass concentration, surface area and specific surface area, andThe unit concentration of dioxin toxicity in fine particles is relatively high. According to respiratory sedimentation simulation calculations, the alveolar area will bear a higher unit concentration of dioxin sedimentation toxicity in ultra-fine particles., published inEnviron. Res..

Journal of Hazardous Materials 423 (2022) 127032

Environmental Research 214 (2022) 113806

Potential emissions from green energy—application and basic research

Study of ultrafine particle emissions from oxygen-enriched fuels.In recent years, efforts have been devoted to the potential emissions that alternative fuels and "clean fuels" may produce. Oxygen-enriched emulsion fuels have been proven to reduce emissions of toxic pollutants such as PM, CO, NOx (when containing a small amount of water) and even PAHs, PCDD/Fs and other toxic pollutants. , the applicant studied the emissions of highly toxic oxidizing/combustible substances such as NPAHs, OPAHs, OPEs, and CFRs when diesel engines use glycerol emulsified diesel fuel, and obtainedAn important finding is that the toxic equivalent concentration of NPAHs in ultrafine particles accounts for 50% of the total PAHs homologues, revealing that "clean fuels" may still have undiscovered potential toxic emissions., the results were published inChemosphere.

Study the high-temperature surface atomization mechanism and main control parameters of droplets.The physical and chemical properties of renewable fuels and fossil fuels are close but not exactly the same. Therefore, the burner must be adjusted based on the correlation between the physical and chemical properties of the oil and spray, primary/secondary atomization, and combustion. Among them, it is a common phenomenon for high-viscosity fuel (such as bio-oil) to adhere to the wall and burn, causing additional HC, PM and UPF emissions. Study the idealized experiment of vertical droplets in a high-temperature liquid pool/liquid film, using a high-speed camera (3272 fps) to capture hot droplets in contact with a low-temperature liquid film, simulating the wall-adhering behavior of droplets with different temperatures, flow rates and pressures under high-speed spraying Penetration, evaporation, sputtering, gas explosion, nucleation boiling and other phenomena, and by controlling the Weber number and Ohnesorge number to achieve the purpose of accelerating evaporation, the results were published inAerosol Air Qual. Res..

Chemosphere 290 (2022) 133244

Aerosol and Air Quality Research 23: 2 (2021) 220366

Aerosol particle emission characteristics, traceability and hot zone research

Research on traceability of aerosol particles. It is mainly divided into three parts: (1) Receptor method, which establishes a fingerprint database of characteristic components such as PM2.5 mass, ions, metals, carbon and L-glucose emitted by different pollution sources, and then calculates the impact of each pollution source on the air based on the chemical mass balance model. The contribution of PM2.5 mass concentration in the air was analyzed, and the global meteorological data of the National Oceanic and Atmospheric Administration was used to complete a three-dimensional reverse trajectory calculation and simulation to clarify the transmission path. (2) The second is the air quality source model. Based on the composite emission situation of multiple types of urban pollution sources, domestic pollution source emission rate data (TEDS), surface and high-altitude weather data, and terrain data are imported to calculate the concentration of aerosol particles in the air. And compare and correct with the detection value to achieve predictable results. (3) Cooperate with the National Institutes of Health to conduct health risk research on PM2.5 components in four domestic urban, rural, industrial and background areas. The results give the characteristics of the main carcinogenic/non-carcinogenic incremental risks of PM2.5 in each area. Metal composition is an important basis for selecting control objects. The aforementioned research results were published inSci. Tot. Environ.,Environ. Pollut.,Aerosol Air Qual. Res..

Environmental Pollution 275 (2021) 116652

Analysis of spatial and temporal distribution of real-time monitoring of small area near surface emissions. Cooperated with Prof. Ming-Yeng Lin to integrate an electric-driven mobile monitoring system equipped with laser particle size distribution counters such as DustTrak, P-Trak, FMPS, etc., using microAeth for real-time monitoring of carbon black and PAS for PAHs analysis, and established with GIS Real-time monitoring map. By coupling simulation incremental analogy and two-dimensional real-time monitoring system analogy, urban priority controlled objects and key health hazard areas can be efficiently located. This system can also be used as a technology to confirm the effectiveness of surface emission control strategies, such as idle stalling and street cleaning. , setting off firecrackers, setting up air purification areas, etc. The research results were published in Aerosol Air Qual. Res. and J. Air. Waste Manage.

Optimizing waste thermal treatment ;

Integrated Medium High Dilution Low Oxygen (MILD) Combustion-Hot Melt Technology

Integrate MILD combustion and hot melt technology into one burner, using exhaust gas recirculation in the furnace to preheat reactants and dilute combustible gas, significantly reducing NOx emissions.CFD is used to predict the heat-flow-chemical multi-field interaction rules of circulation in the furnace, and quantitatively supply waste heat to the hot melt zone to promote the reaction of CO, H2O, NOx and carbon-based compounds in the drying zone, and then rapidly oxidize in the secondary combustion chamber.The integrated technology avoids a large amount of heat loss caused by traditional excess air incineration, can save up to 48.7% of fuel, effectively reduces carbon emissions and significantly reduces the emissions of various conventional/unconventional pollutants., published inWaste Management.

Waste Management 126 (2021) 706-718

Research on the generation mechanism and control technology of persistent pollutants in unstable combustion

Research on furnace start-up control in incineration plants to reduce emissions of non-conventional pollutants in Taiwan.In order to avoid the unstable fuel/air, temperature, turbulence, and heat transfer environment during the start-up stage of waste incineration, large amounts of conventional and non-conventional harmful air pollutants are emitted thousands of times, resulting in huge potential health risks. By controlling the stepwise heating process, the adsorption amount and injection time of activated carbon and lime, and the injection of inhibitors containing sulfur and nitrogen components, the system is effectivelyInhibit POPs out of phasenovoSynthesis, reducing POPs emissions by 75%, published inJ. Hazard. Mater.,Aerosol Air Qual. Res.wait.

Use a circulating water tank to quench the incineration bottom slag, and measure the fingerprint changes of dioxin regeneration at different temperatures.first observednovoRe-synthesis continues to occur in the gas phase at <100°C, because the low-temperature oxygen-rich air is heated by the high-temperature bottom slag, dioxin is generated at local high temperatures (200–400°C) in the solid gap, and its volatilization is inhibited by the cold surface of the outer layer. The solid-phase residence time is increased to increase the chlorination reaction.Confirms that burner shutdown control is as important as burner start control. Then it was proposed to reduce the resynthesis of POPs in the combustion bottom slag by controlling the shutdown temperature.The quenching device is used to reduce the dioxin concentration in the bottom slag to 1/850 of that during natural cooling treatment, eliminating the need for hot melting/vitrification post-processing of the bottom slag., reducing incineration costs and carbon emissions, published inWaste Management.

Journal of Hazardous Materials 299 (2015) 206-214

Waste Management 95 (2019) 316-324

Research on Renewable Liquid Multi-Mixture Fuels—Combustion Diagnostics, Engines and Incineration

Application of microemulsion fuel spray combustion in engines

Application of micro-emulsification of short carbon chain compounds with diesel fueloil engine, promoting efficient and low-emission combustion.Thermal stable propylene is produced through ultrasonic multi-layer film emulsification technologyKetone, n-/isobutanol, ethanol, n/isopropyl alcohol–diesel emulsion. In addition, the ABE aqueous solution after filtration and simple distillation of the crude fermentation product was also used as one of the raw materials to prepare a stablemicroemulsified diesel. Due to differences in the physical and chemical properties of each component, the droplets after primary atomization will undergo micro-explosion at high temperatures, improving the quality of secondary atomization and oil-gas mixing, reducing the specific fuel consumption of internal combustion engines, traditional/unconventional harmful pollutant emissions, and indirectlyCO2-eq emissions suppressed,He is an early international scholar who proposed and tried to use ABE as an alternative fuel for internal combustion engines, and was published in top journals in the field.Applied Energy Post a Highly Cited Paper. The above results have caused repercussions in the international internal combustion engine community, leading to the University of Illinois, the Department of Energy's Oak Ridge National Laboratory and the University of North Carolina in the United States, Oxford Brooke University in the United Kingdom, Aalto University in Finland, the University of Southern Queensland in Australia, and China The University of Science and Technology of China, Wuhan University, Central South University, Tianjin University and Beijing Institute of Technology conducted a series of studies.

Observe the spray, micro-explosion, evaporation and combustion processes of emulsified fuel through flame visible light, laser shadow, and schlieren oil beam imaging technologies, thereby diagnosing the mechanism by which specific emulsified oil improves internal combustion engine performance and emissions.It was found that emulsified fuel has a shorter oil beam penetration depth and a larger cone angle.One-time atomization effect is obviously better than diesel;Due to the difference in boiling point and density between the dispersed/continuous phase, the oil willThe micro-explosion phenomenon of droplets improves secondary atomization; In addition, in the constant volume combustion bomb test, the microemulsion reduced the combustion temperature and inhibited the generation of PM and NOx. The results were published inFuel.

This article explains the reaction kinetics of the negative temperature coefficient (NTC) of low-temperature combustion of short carbon chain compounds to inhibit the formation of carbon black particles.forFlexibly control engine low temperature combustion (LTC) to achieve synchronized control of NOx-soot, using fuels with different NTC ignition delay effects, established a 2-D model and experiment of laminar diffusion combustion, and used 0-D simulation to calculate the reaction pathway and sensitivity analysis of PAHs and soot precursor A1 generated by low-temperature combustion. It was found that there are three main pathways, two of which oxidation reactions strengthen the NTC phenomenon and produce larger molecular hydrocarbons (about 37-50%), inhibiting the A1 synthesis rate and further reducing the generation of PAHs and soot; conversely, the third high-temperature cracking pathway Easily generate C2-C4. For fuels that are more sensitive to NTC, low-temperature combustion is prone to the pre-oxidation pathway, which inhibits PAHs and soot emissions. In the 2D physical and chemical coupling simulation, Keto-peroxide and CHO are selected to represent the intermediate products of NTC intensity. This method can explore the basic reaction dynamics of each fuel combustion emission, published inACS Omega.

Applied Energy 109 (2013) 182-191

Fuel 123 (2014) 218-229

ACS Omega 6 (2021) 15156-15167

Research on resource utilization of aqueous waste oil and organic wastewater

Use waste solvents with low calorific value to continuously emulsify heavy oil, recycle waste heat and waste water from the process, and solve the zero-emission bottleneck.Heavy oil stickyHigh temperature and high specific gravity, poor atomization effect, resulting in poor oil and gas mixing and incomplete combustion, low energy efficiency and high emissions, and can easily cause carbon deposition in the system and reduce the thermal efficiency of the boiler. After emulsifying heavy oil with waste solvents and wastewater containing methanol/isopropyl alcohol/acetone,It greatly improves the secondary atomization effect of fuel and recovers the calorific value of wastewater. The total thermal efficiency is increased by >14%., and realizes continuous emulsification oil supply combustion in steam boilers; significantly improves the oil and gas premixing state while suppressing PM, CO, HC and PAH emissions; the oil and gas distribution is more even, reducing the occurrence of high temperatures in the flame front area and thus inhibiting the generation of NOx; no sulfur and chlorine components The solvent replaced part of the heavy oil, reduced the concentration of SO2 and HCl in the flue and alleviated system corrosion. The results were published inEnergy & Fuels.

Proposes the utilization technology of direct combustion of water-containing waste cooking oil (WCO) incinerator and blended diesel engine.my country's cooking habits produce a large amount of WCO, and existing value-added utilization technologies include homogeneous catalysis (high secondary pollution and water consumption), supercritical methods (high equipment operating costs and energy consumption), and bioenzymatic methods (the product glycerol inhibits the yield and enzyme life), each has its own limitations and is accompanied by crude glycerol processing problems. Thermogravimetric analysis found that after filtrationWCO can be rapidly oxidized and degraded above 500°C, and is suitable for constant pressure and continuous combustion environments. It can be used as co-combustion of low calorific value solid fuels (such as garbage incineration, RDF-5 combustion), and because it contains oxygen and lower pollution precursors (sulfur, bromine and aromatic hydrocarbons), it can effectively reduce emissions of PAHs, Dioxins and PCDEs. In addition, mixing a small amount of WCO with light oil can be stably and safely used in diesel engines, and has good lubrication effect under long-term operation. The results are affected byAerosol Air Qual. Res.Post and focus.

The added value of transesterification of waste cooking oil and micro-emulsification of crude glycerin technology and the reduction of coagulable particulate matter.Diesel and crude glycerol are produced from waste cooking oil through homogeneous catalysis. The two are used as pure diesel and blended into mixed diesel and micro-emulsified diesel respectively, and their performance and emissions are tested in a diesel engine. It was found that when the amount of waste cooking oil converted into diesel is <20%, the emissions of PM, metals, PAHs, Dioxins and persistent organic pollutants (POPs) can be reduced under various working conditions. In the durability test, for the second and third phase diesel Vehicles have significant emission reduction effects. On the other hand, crude glycerol can be added through ABE solution, and ultrasonic microemulsification technology is used to form a homogeneous dispersed phase with a diameter of only 0.1 µm to stabilize microemulsified diesel. The test was carried out in a single-cylinder diesel engine. The results show that burning microemulsified diesel has an impact on PM, NOx and PAHs have synergistic inhibitory effects, among which,The significant reduction of condensable particulate matter will become the focus of subsequent research on water-containing fuel combustion and emissions., the results were published inChemosphere.