In order to explore the remediation effects of lignite and biochar on Zn-contaminated soil,this experiment studied the impacts of adding lignite and biochar on soil respiration,soil enzyme activity,and organic carbon ...In order to explore the remediation effects of lignite and biochar on Zn-contaminated soil,this experiment studied the impacts of adding lignite and biochar on soil respiration,soil enzyme activity,and organic carbon in Zn-contaminated soil through soil culture experiments,which provided a theoretical basis for the remediation and improvement as well as for the development and utilization of Zn-contaminated soil.The study was an L8(4×2^(2))orthogonal experimental design with eight treatments,in which there were four levels of Zn contamination concentration(Z0:0;Z1:125 mg•kg^(-1);Z2:250 mg•kg^(-1);Z3:500 mg•kg^(-1)),low-Zn(125-250 mg•kg^(-1))and high-Zn(500 mg•kg^(-1)),two levels of lignite(H0:0;H1:13.33 g•kg^(-1)),two levels of biochar(C0:0;C1:3.33 g•kg^(-1)),with four replicates per treatment.The results showed that lignite or biochar and their interaction had extremely significant effects on both respiration rate and accumulation in Zn-contaminated soil.Among the high Zn-contaminated treatments,the mixed application of lignite and biochar(Z3H1C1 treatment)had the fastest soil respiration rate and the highest soil respiration accumulation.Lignite,biochar and their interaction had significant or extremely significant effects on sucrase,catalase and polyphenol oxidase activities in Zn-contaminated soil.Among the high Zn-contaminated treatments(Z3),the addition of biochar alone had the most significant effects on the increase of soil sucrase and catalase enzyme activities,while the mixed application of lignite and biochar had the most significant effects on the increase of soil polyphenol oxidase activity.Lignite,biochar and their interaction had significant or extremely significant effects on the total organic carbon,active organic carbon and microbial carbon content of Zn-contaminated soils.Soil total organic carbon content in general peaked at day 80.Among the high Zn-contaminated treatments,the addition of biochar alone had the most significant effects on the total organic carbon content of the soil,while the mixed application of lignite and biochar had the most significant effect on the microbiomass carbon content.展开更多
Lignite provides energy security and contributes economically.However,it also causes dirty outcomes in terms of climate aspect.In addition to the energy and climate dimensions of the Sustainable Development Goals,ther...Lignite provides energy security and contributes economically.However,it also causes dirty outcomes in terms of climate aspect.In addition to the energy and climate dimensions of the Sustainable Development Goals,there is also a water issue:lignite is usually found submerged below the local groundwater tables.Mining lignite could be exploited to achieve drinkable and agriculturally usable water.In today’s literature,while the impact of lignite production on global warming and emissions are already highly discussed,the water management side of the issue is regularly omitted.However,considering the complex interlink between these three areas(the Water-Energy-Climate(WEC)nexus)is necessary within policy coherence,which is mostly ignored even though it is one of the development targets.Here in this framework,Turkiye,which aims to reduce its heavy dependency on energy imports,is worth studying because almost all of its coal,the country’s largest fossil resource,is lignite.Therefore,this study examines the WEC nexus related to lignite production and combustion and seeks policy coherence between their outputs in the context of Turkiye’s historical steps to climate change mitigation,specifically oriented with the Paris Agreement.This story expands from the absence of specific development policy objectives to the practicalities of politics and economics.展开更多
In this paper,the effect of vibration intensity on the spatial distribution of sulfur content in bed particles was studied.The effects of vibration and airflow on the mechanical characteristics of particles were studi...In this paper,the effect of vibration intensity on the spatial distribution of sulfur content in bed particles was studied.The effects of vibration and airflow on the mechanical characteristics of particles were studied,the collision behavior mode of particles was determined,the spatial saltation law of particles was investigated,the spatial functional axis of beds was determined,and the saltation separation period of particles was determined.The test results show that:When separation bed provides inlet airflow velocity(U_(in)) is 2.55 m/s,the airflow distribution interval of I,II and III areas were U_(I)=2.55-2.57 m/s,U_(II)=1.33-1.35 m/s,U_(III)=0.35-0.38 m/s,respectively;when separation bed vibration amplitude (A)A=2.4-2.5 mm,separation bed vibration frequency (f) f=23-24 Hz,the desulfurization effect is the best.When vibration intensity (Γ)Γ=1.22,U_(in)=1.05 m/s,the particles have disordered contact and collision behavior.WhenΓ=14.89,U_(in)=3.18 m/s,the particles have a transition cataclastic collision.WhenΓ=5.80,U_(in)=2.55 m/s,the particles have directional collision behavior.It is determined that the OX axis is the transverse stable diffusion axis of the material,the OY axis is the longitudinal gradient transport axis of the material,and the OZ axis is the vertical density cascade distribution axis of the material.When separation time (T) T=0-10 s was the period of disorderly diffusion and mixing of particles,T=10-20 s was the period of directional migration and stratification of particles,and T=20-30 s was the period of cascade distribution and separation of particles.Finally,separation experiments conducted under optimal operating parameters demonstrated that the clean coal yield was 72.02%with a sulfur content of 0.98%.展开更多
Water scarcity and soil salinization pose significant challenges to agriculture in the West Liaohe Plain,eastern Inner Mongolia,China.Shallow-buried drip irrigation can improve soil water use efficiency to alleviate w...Water scarcity and soil salinization pose significant challenges to agriculture in the West Liaohe Plain,eastern Inner Mongolia,China.Shallow-buried drip irrigation can improve soil water use efficiency to alleviate water shortage in agriculture and the application of lignite humic acid reduces the adverse effects of soil salinization.However,further research is needed to investigate the effects of different application rates of lignite humic acid and humic acid-based combined amendment on soil physicochemical properties,nutrient contents,and crop yield in saline-sodic farmlands under shallow-buried drip irrigation.A two-year field experiment was conducted with control without any amendment(CK),three treatments amended with 3 t/ha(H1),6 t/ha(H2),and 12 t/ha(H3)lignite humic acid,and three application rates with 15 t/ha(T1),22.5 t/ha(T2),and 30 t/ha(T3)lignite humic acid-based combined amendment in 2021 and2022.The results showed that H3 reduced soil bulk density,p H,electrical conductivity,and total alkalinity,while increasing the contents of soil organic matter,total nitrogen,and available potassium in the two-year experiment.Moreover,the maize yield in H3 increased by an average of 35.5%.T2 decreased soil bulk density,p H,total alkalinity,and increased maize yield by 16.2%,compared to the first year.These results suggest that T2 consistently improved both soil quality and crop yield.Correlation analyses showed that lignite humic acid and its complexes promote maize growth and increase yield by increasing soil organic matter and total nitrogen while reducing soil salinity and total alkalinity.Based on the comprehensive analysis of the field data and the results of the comprehensive evaluation of soil quality,it was determined that the appropriate improvement measures for saline-sodic farmlands under shallow-buried drip irrigation are the application of 12 t/ha of lignite humic acid and 22.5 t/ha of lignite humic acid-based combined amendment.This study demonstrates the effectiveness of lignite humic acid and its combined amendment in mitigating the constraints of saline-sodic farmlands and enhancing crop yields,providing a sustainable solution for improving saline-sodic farmlands in the West Liaohe Plain.展开更多
Silicon oxide(SiO_(x),0<x≤2)has been recognized as a prominent anode material in lithium-ion batteries and sodium-ion batteries due to its high theoretical capacity,suitable electrochemical potential,and earth abu...Silicon oxide(SiO_(x),0<x≤2)has been recognized as a prominent anode material in lithium-ion batteries and sodium-ion batteries due to its high theoretical capacity,suitable electrochemical potential,and earth abundance.However,it is intrinsically poor electronic conductivity and excessive volume expansion during potassiation/depotassiation process hinder its application in potassium-ion batteries.Herein,we reported a hierarchical porous C/SiO_(x)potassium-ion batteries anode using lignite as raw material via a one-step carbonization and activation method.The amorphous C skeleton around SiO_(x)particles can effectively buffer the volume expansion,and improve the ionic/electronic conductivity and structural integrity,achieving outstanding rate capability and cyclability.As expected,the obtained C/SiO_(x)composite delivers a superb specific capacity of 370 mAh g^(-1)at 0.1 A g^(-1)after 100 cycles as well as a highly reversible capacity of 208 mAh g^(-1)after 1200 cycles at 1.0 A g^(-1).Moreover,the potassium ion storage mechanism of C/SiO_(x)electrodes was investigated by ex-situ X-ray diffraction and transmission electron microscopy,revealing the formation of reversible products of K_(6.8)Si_(45.3)and K_(4)SiO_(4),accompanied by generation of irreversible K2O after the first cycle.This work sheds light on designing low-cost Si-based anode materials for high-performance potassium-ion batteries and beyond.展开更多
Biogasification of coal is important for clean utilization of coal. Experiments on the fermentation of single lignite, single straw and their mixture were performed to explore the variation characteristics of gas prod...Biogasification of coal is important for clean utilization of coal. Experiments on the fermentation of single lignite, single straw and their mixture were performed to explore the variation characteristics of gas production potential, microbial community and methanogenic metabolic pathways of mixture. Research has shown that mixed fermentation of lignite and straw significantly promoted biomethane production. The abundance of hydrolytic acidifying functional bacteria genera (Sphaerochaeta, Lentimicrobium) in mixed fermentation was higher than that in the fermentation of single lignite and single straw. The abundance of some key CAZy metabolic enzyme gene sequences in mixed fermentation group was increased, which was favorable to improve methane production. Aceticlastic methanogenesis was the most critical methanogenic pathway and acetic acid pathway was more competitive in methanogenic mode during peak fermentation. Macrogenomics provided theoretical support for the claim that mixed fermentation of coal and straw promoted biomethane metabolism, which was potentially valuable in expanding methanogenesis from mixed fermentation of lignite with different biomasses.展开更多
To enhance methane production efficiency in lignite anaerobic digestion and explore new ways for residual sludge utilization, this study employed the co-fermentation of lignite and residual sludge for biomethane conve...To enhance methane production efficiency in lignite anaerobic digestion and explore new ways for residual sludge utilization, this study employed the co-fermentation of lignite and residual sludge for biomethane conversion. The bacterial colony structure, metabolic pathways, and interactions between residual sludge and lignite in anaerobic methanogenic fermentation with different mass ratios were analyzed using macrogenomics sequencing. This study aimed to explore the mechanisms involved in the co-anaerobic fermentation of lignite and residual sludge. The results indicated that the addition of sludge enhanced the metabolic pathways in hydrolysis acidification, hydrogen-acetic acid production, and methanation phases. Notably, the enhancement of acetate- and carbon dioxide-nutrient metabolic pathways was more pronounced, with increased activity observed in related enzymes such as acetic acid kinase (k00925) and acetyl coenzyme synthetase (K01895). This increased enzymatic activity facilitated the microbial conversion of biomethane. The results of the study indicated that the sludge exhibited a promotional effect on the methane produced through the anaerobic fermentation of lignite, providing valuable insights for lignite and residual sludge resource utilization.展开更多
The paper presents the change in grain-size composition of lignite under cyclic freezing-thawing (FTC) and wetting-drying (WDC). The article shows that in the spring and autumn periods the lignites can be subjected to...The paper presents the change in grain-size composition of lignite under cyclic freezing-thawing (FTC) and wetting-drying (WDC). The article shows that in the spring and autumn periods the lignites can be subjected to repeated freezing-thawing and wetting-drying, which determines the possibility of changing their grain-size composition and structure. Experimental studies in laboratory conditions on the influence of cyclic freezing-thawing (FTC) and wetting-drying (WDC) on the quality indicators of lignites have been carried out, their granulometric (fractional) composition has been studied. Freezing-thawing cycle conditions are as follows (FTC): minimum exposure temperature: -20°C;maximum: +5°C;relative humidity: 30%;number of processing cycles: 3. Wetting-drying cycles are as follows (WDC): drying temperatures are +20, +40, +60, +80°C, drying time 90 minutes, the coals are further subjected to rain (soaking) for a period of water saturation to humidity of 30% - 40% and dry again. The number of wetting-drying cycles is 3 times. The tests have revealed the destructive effects of FTC and WDC on the samples of lower metamorphic grade coal, and the cycles of wet-dry lead to the much higher yield of fine sizes (-6+0;-13+0 mm) than the cycles of freeze-thaw. Furthermore, it is found that the increase in the yield of fines depends on the heating temperature: coal disintegration proceeds more intensively at a higher temperature of drying.展开更多
The adsorption characteristics of virgin and potassium permanganate modified lignite semi-coke (SC) for gaseous Hg were investigated in an attempt to produce more effective and lower price adsorbents for the control...The adsorption characteristics of virgin and potassium permanganate modified lignite semi-coke (SC) for gaseous Hg were investigated in an attempt to produce more effective and lower price adsorbents for the control of elemental mercury emission. Brunauer-Emmett- Teller (BET) measurements, X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were used to analyze the surface physical and chemical properties of SC, Mn-SC and Mn-H-SC before and after mercury adsorption. The results indicated that potassium permanganate modification had significant influence on the properties of semi-coke, such as the specific surface area, pore structure and surface chemical functional groups. The mercury adsorption efficiency of modified semi-coke was lower than that of SC at low temperature, but much higher at high temperature. Amorphous Mn7+, Mn6+ and Mn4+ on the surface of Mn-SC and Mn-H-SC were the active sites for oxidation and adsorption of gaseous Hg~, which oxidized the elemental mercury into Hg2+ and captured it. Thermal treatment reduced the average oxidation degree of Mn2+ on the surface of Mn-SC from 3.80 to 3.46. However, due to the formation of amorphous MnOx, the surface oxidation active sites for gaseous Hg0 increased, which gave Mn-H-SC higher mercury adsorption efficiency than that of Mn-SC at high temperature.展开更多
The process of lignite desulphurization via its treatment by an oxidant(air or air–steam mixture)has been studied.The research objective was useful determination of steam application in oxidative lignite desulphuriza...The process of lignite desulphurization via its treatment by an oxidant(air or air–steam mixture)has been studied.The research objective was useful determination of steam application in oxidative lignite desulphurization.It has been proved that the water steam should be included in the oxidant composition to increase the hydrogen sulphide and combustible constituent content in the gases obtained during the processes under research.The impact of factors which affect the reactions between solid(in our case–lignite)and gaseous reagent(oxidant,i.e.air and or air–steam mixture)upon the research process has been investigated,if these reactions occur in the kinetic area.Such factors are linear rate of oxidant movement and coal grain size.The values of oxidant movement linear rate and coal grain size,which the reaction transfer from pyrite sulphur and organic content of lignite from diffusion into kinetic area occurs by,have been determined.Under these‘‘transfer’’conditions,the values of coefficients of oxidant mass transfer(β,m/s)as well as Sherwood criteria and boiling layer differences have been calculated.展开更多
Lignite bio-solubilization is a promising technology for converting solid lignite into oil.This study concerns the adsorption of lignite-solubilizing enzymes onto the lignite surface.Adsorption capacity, infrared spec...Lignite bio-solubilization is a promising technology for converting solid lignite into oil.This study concerns the adsorption of lignite-solubilizing enzymes onto the lignite surface.Adsorption capacity, infrared spectral analysis and driving forces analysis are studied as a way to help understand the bio-solubilization mechanism.The results show that the amount of lignite bio-solubilization is proportional to the amount of adsorbed lignite-solubilizing enzymes.An increase in lignite-solubilizing enzyme adsorption of 10% leads to a 7% increase in lignite bio-solubilization.However, limited amounts of enzymes can be adsorbed by the lignite, thus resulting in low percentages of bio-solubilization.Infrared spectral analysis shows that side chains, such as hy-droxyl and carbonyl, of the lignite structure are the main, and necessary, structures where lignite-solubilizing enzymes attachto the lignite.Furthermore, driving force analysis indicates that the electrostatic force between lignite and enzymes is the main adsorption mechanism.The forces are influenced by solution pH levels, the zeta potential of the lignite and the isoelectric points of the en-zymes.展开更多
A white rot fungus strain, Trichoderma sp.AH, was isolated from rotten wood in Fushun and used to study the mechanism of lignite bio-solubilization.The results showed that nitric acid pretreated Fushun lignite was sol...A white rot fungus strain, Trichoderma sp.AH, was isolated from rotten wood in Fushun and used to study the mechanism of lignite bio-solubilization.The results showed that nitric acid pretreated Fushun lignite was solubilized by T.sp.AH and that extracellular proteins from T.sp.AH were correlated with the lignite bio-solubilization results.In the presence of Fushun lignite the extracellular protein concentration from T.sp.AH was 4.5 g/L while the concentration was 3 g/L in the absence of Fushun lignite.Sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE) of the extracellular proteins detected at least four new protein bands after the T.sp.AH had solubilized the lignite.Enzyme color reactions showed that extracellular proteins from T.sp.AH mainly consisted of phenol-oxidases, but that lignin decomposition enzymes such as laccase, peroxidase and manganese peroxidases were not present.展开更多
The surface functional groups and pyrolysis characteristics of lignite irradiated by microwave were comparatively studied to evaluate the feasibility of using industrial 915 MHz for lignite drying. The drying kinetics...The surface functional groups and pyrolysis characteristics of lignite irradiated by microwave were comparatively studied to evaluate the feasibility of using industrial 915 MHz for lignite drying. The drying kinetics, micro structure, chemical functional groups, re-adsorption properties, and pyrolysis characteristics of the dried coal were respectively analyzed. Results indicated that for typical Chinese lignite studied in this paper, 915 MHz microwave drying was 7.8 times faster than that of the hot air drying. After industrial microwave drying, the sample possessed much higher total specific surface area and specific pore volume than that of air dried sample. The oxygen functional groups and re-adsorption ratio of microwave irradiated coal decreased, showing weakened hydrophilicity. Moreover, during the pyrolysis of the coal dried by hot air and microwave, the yield of tar largely increased from 1.3% to 8.5% and the gas production increased correspondingly. The composition of the tar was also furtherly analyzed, results indicated that Miscellaneous hydrocarbons(HCs) were the main component of the tar, and microwave irradiation can reduce the fraction of polycyclic aromatic hydrocarbons(PAHs) from 26.4% to 22.7%.展开更多
The feasibility and adsorption effect of lignite activated carbon for phenol removal from aqueous solutions were evaluated and investigated. A series of tests were performed to look into the influence of various exper...The feasibility and adsorption effect of lignite activated carbon for phenol removal from aqueous solutions were evaluated and investigated. A series of tests were performed to look into the influence of various experimental parameters such as contact time, initial phenol concentration, temperature, and pH value on the adsorption of phenol by lignite activated carbon. The experimental data were fitted well with the pseudo-second-order kinetic model. The adsorption is an endothermic process and conforms to Freundlich thermodynamic model. The results indicate that the lignite activated carbon is suitable to be used as an adsorbent material for adsorption of phenol from aqueous solutions.展开更多
A process of recovering Ge by chlorinating masting was put forward. GeCl4 was separated and recovered from lignite ash because of its low boiling point. Kinetic analysis indicates that the chlorinating roasting proces...A process of recovering Ge by chlorinating masting was put forward. GeCl4 was separated and recovered from lignite ash because of its low boiling point. Kinetic analysis indicates that the chlorinating roasting process fits with the unreacted-core shrinking model and the reaction rate equation corresponds to 1 - 2a/3 - (1 - a)2/3 = kt. The apparent activation energy Ea is calculated to be 22.36 kJ·mol^-1. The diffusion of product layer serves as the rate-controlling step in this process. When the roasting temperature is 250℃, the roasting time is 60 min, the con- centration of hydrochloric acid is 10 mol/L, and the ratio of liquid to solid is 10 (mHCl/ash = 10), and 90% Ge in lignite ash can be recovered.展开更多
The distribution and verticals variation of geochemical components in the Kasnau-Matasukh lignites of Nagaur Basin, Rajasthan, were investigated using microscopy, proximate and ultimate analyses, Rock-Eval Pyrolysis, ...The distribution and verticals variation of geochemical components in the Kasnau-Matasukh lignites of Nagaur Basin, Rajasthan, were investigated using microscopy, proximate and ultimate analyses, Rock-Eval Pyrolysis, X-ray diffraction and Fourier Transform Infrared analyses, and major/minor/trace element determination. The relationship of elements with ash content and with macerals have also been discussed. These lignites are stratified, black, dominantly composed of huminite group macerals with subordinated amounts of liptinite and inertinite groups. They are classified as type-III kerogen and are mainly gas prone in nature. The concentration (in vol%) of mineral matter is seen to increase towards upper part of seam and so is the concentration (in wt%) of the volatile matter, elemental carbon and sulphur. The common minerals present in these lignitesare mixed clay layer, chlorite, and quartz as identified by X-ray diffraction study. Compared with world average in brown coal, the bulk concentration of Cu is anomalously high in most of the samples while Cd is 2-3 times high and Zn is high in one band. Based on interrelationship, different pyrite forms are noticed to have different preferential enrichment of various elements. The concentration of disseminated pyrite is more than the other pyrite forms and is followed by discrete pyrite grains and massive pyrite.展开更多
The drying processes are always applied prior to the transportation or utilization of lignite, and result in notable changes in the stabilities of lignite. In this paper, the study on the effects of nitrogen and MTE d...The drying processes are always applied prior to the transportation or utilization of lignite, and result in notable changes in the stabilities of lignite. In this paper, the study on the effects of nitrogen and MTE drying process on the physico-chemical properties and stabilities of Zhaotung lignite was carried out. The briquettes produced by MTE drying in this study were 150 mm in dimension, and so had a much larger particle size than nitrogen- dried samples. Nitrogen adsorption, mercury intrusion porosimetry and scanning electron microscopy all suggested that drying was accompanied by the transformation of larger pores into smaller ones. Compared to nitrogen drying, the pore structures could be stabilized by the MTE process. The soluble salts were removed during MTE drying which resulted in the decrease in ash and the concentrations of some of the major metals. The removal of water enhanced the hydrophilicity of nitrogen dried samples, but did not affect the hydrophilicity of MTE dried samples. The moisture holding capacity of MTE dried samples reduced faster than nitrogen dried samples with the decrease of residual moisture content. The moisture readsorption processes of MTE dried sam- ples were strongly inhibited due to the much larger particle size of sample produced by MTE drying than nitrogen drying. The susceptibility to spontaneous combustion, indicated by cross point temperature and self-heating tests, of nitrogen and MTE dried samples increased with the decrease of residual moisture content. The MTE dried samples are more liable to spontaneous combustion than nitrogen dried samples with the same residual moisture and particle size. However, the larger particle size of the MTE product made it more stable with respect to spontaneous combustion and also moisture readsorption.展开更多
Lignite samples collected from Vastan, Rajpardi and Tadkeshwar lignite mines of Cambay basin (Gujarat) were subjected to organic petrographic investigations and geochemical analyses and the data, thus generated, is ...Lignite samples collected from Vastan, Rajpardi and Tadkeshwar lignite mines of Cambay basin (Gujarat) were subjected to organic petrographic investigations and geochemical analyses and the data, thus generated, is used to reconstruct the paleodepositional history of these lignite sequences. The lignites of Cambay basin dominantly comprise huminite maceral group (71.6%-86.3%) followed by liptinite (10.1%-19.3%) and inertinite (3.6%-11.0%) maceral groups. The mineral matter varies from 9.0% to 20.0%. The petrography based facies model indicates that these lignites have high values of gelification index (GI) and low tissue preservation index revealing a continuous wet condition in the basin and a relatively slower rate of subsidence during the decay of organic matter. On several occasions, during the formation of seams in Tadkeshwar, Rajpardi and Vastan mines, the value of GI exceeded 10 which indicates a forest permanently flooded and the cause of pronounced degree of degradation. However, few sections in Tadkeshwar seam had relatively drier spells of environmental conditions due to fluctuation in the water table as revealed by moderately high content of inertinite macerals. This is specially indicated by the occurrence of funginite which normally thrives in the upper oxy- genated peatigenic layer and indicates prevalence of oxic conditions during plant deposition. Such conditions prevailed during a transgressive phase but there were intermittent fluvial activities also giving rise to supratidal flood plain as reflected in the form of associated carbonaceous shales in the basin.展开更多
Soluble portions(SPs) 1-4(SP1-SP4) were afforded from sequentially dissolution and alkanolyses of Baiyinhua lignite(BL) in cyclohexane,CH3OH,CH3CH2OH,and(CH3)2CHOH at 300℃.They were analyzed with a gas chromatograph/...Soluble portions(SPs) 1-4(SP1-SP4) were afforded from sequentially dissolution and alkanolyses of Baiyinhua lignite(BL) in cyclohexane,CH3OH,CH3CH2OH,and(CH3)2CHOH at 300℃.They were analyzed with a gas chromatograph/mass spectrometer and quadrupole exactive orbitrap mass spectrometer(QEOTMS) with an atmosphere pressure chemical ionization source in positive-ion mode,while BL was characterized with an X-ray photoelectron spectrometer(XRPES).The results show that the yields of SP2 and SP3 are much higher than those of SP1 and SP4,and the total SP yield is ca.39.0%.According to the analysis with XRPES,pyrrolic nitrogen atoms are the most abundant nitrogen existing forms in BL.Thousands of nitrogen-containing aromatics(NCAs) were resolved with QEOTMS and their molecular masses are mainly in the range of 200-450 u.The main NCAs are N1O1 and N1O2 class species with double bond equivalent values of 4-18 and carbon numbers of 7-30.The nitrogen atoms appear in pyridine s,quinolines,benzoquinolines or acridine,and dibenzoquinolines or naphthoquinolines,while the oxygen atoms exist in methoxy and furan rings.展开更多
With lignite after vacuum drying as the raw material,a series of Zn-based sorbents were prepared by static impregnation,ultrasonic-assisted impregnation,bubbling-assisted impregnation and high-pressure impregnation.Th...With lignite after vacuum drying as the raw material,a series of Zn-based sorbents were prepared by static impregnation,ultrasonic-assisted impregnation,bubbling-assisted impregnation and high-pressure impregnation.The physical properties and the desulfurization performances of Zn-based sorbents were studied systematically by XRD,BET,AAS characterization techniques and the fixed-bed desulfurization evaluation apparatus.The sorbents obtained by high-pressure impregnation method have a larger specific surface area,pore volume and pore diameter comparing with other methods,which is conducive to the sulfidation reaction of hydrogen sulfide gas in the sorbent.The effects of pressure during the high-pressure impregnation and concentration of Zn(NO3)2 precursor solution on the sorbents properties and desulfurization behavior were investigated.The higher the impregnation pressure and the concentration of impregnation solution are,the greater the amount of the active components are uploaded.However,overhigh impregnation pressure can cause collapse and blocking of the carrier pore.The optimal operating condition of high-pressure impregnation method for preparing the sorbents was the impregnation pressure of 20 atm and the solution concentration of 41%.Under that condition,the sorbent had the best desulfurization ability with a sulfur capacity of 13.94 gS/100 gsorbent and a breakthrough time of 54 h.Its desulfurization precision and efficiency of removing H2S before sorbent breakthrough from the middle temperature gases of 400℃ can reach【5 ppm and】99%,respectively.Sorbents could be regenerated under the condition of 1 vol%O2,20 vol% H2O,0.5 vol% NH3,and N2balance gas.The regenerated sorbent could be used for repeated absorption of H2S with a slight decrease in desulfurization effect.展开更多
基金Supported by the Special Fund for Agro-scientific Research in Public Interest in China(201503119-06-01)。
文摘In order to explore the remediation effects of lignite and biochar on Zn-contaminated soil,this experiment studied the impacts of adding lignite and biochar on soil respiration,soil enzyme activity,and organic carbon in Zn-contaminated soil through soil culture experiments,which provided a theoretical basis for the remediation and improvement as well as for the development and utilization of Zn-contaminated soil.The study was an L8(4×2^(2))orthogonal experimental design with eight treatments,in which there were four levels of Zn contamination concentration(Z0:0;Z1:125 mg•kg^(-1);Z2:250 mg•kg^(-1);Z3:500 mg•kg^(-1)),low-Zn(125-250 mg•kg^(-1))and high-Zn(500 mg•kg^(-1)),two levels of lignite(H0:0;H1:13.33 g•kg^(-1)),two levels of biochar(C0:0;C1:3.33 g•kg^(-1)),with four replicates per treatment.The results showed that lignite or biochar and their interaction had extremely significant effects on both respiration rate and accumulation in Zn-contaminated soil.Among the high Zn-contaminated treatments,the mixed application of lignite and biochar(Z3H1C1 treatment)had the fastest soil respiration rate and the highest soil respiration accumulation.Lignite,biochar and their interaction had significant or extremely significant effects on sucrase,catalase and polyphenol oxidase activities in Zn-contaminated soil.Among the high Zn-contaminated treatments(Z3),the addition of biochar alone had the most significant effects on the increase of soil sucrase and catalase enzyme activities,while the mixed application of lignite and biochar had the most significant effects on the increase of soil polyphenol oxidase activity.Lignite,biochar and their interaction had significant or extremely significant effects on the total organic carbon,active organic carbon and microbial carbon content of Zn-contaminated soils.Soil total organic carbon content in general peaked at day 80.Among the high Zn-contaminated treatments,the addition of biochar alone had the most significant effects on the total organic carbon content of the soil,while the mixed application of lignite and biochar had the most significant effect on the microbiomass carbon content.
文摘Lignite provides energy security and contributes economically.However,it also causes dirty outcomes in terms of climate aspect.In addition to the energy and climate dimensions of the Sustainable Development Goals,there is also a water issue:lignite is usually found submerged below the local groundwater tables.Mining lignite could be exploited to achieve drinkable and agriculturally usable water.In today’s literature,while the impact of lignite production on global warming and emissions are already highly discussed,the water management side of the issue is regularly omitted.However,considering the complex interlink between these three areas(the Water-Energy-Climate(WEC)nexus)is necessary within policy coherence,which is mostly ignored even though it is one of the development targets.Here in this framework,Turkiye,which aims to reduce its heavy dependency on energy imports,is worth studying because almost all of its coal,the country’s largest fossil resource,is lignite.Therefore,this study examines the WEC nexus related to lignite production and combustion and seeks policy coherence between their outputs in the context of Turkiye’s historical steps to climate change mitigation,specifically oriented with the Paris Agreement.This story expands from the absence of specific development policy objectives to the practicalities of politics and economics.
基金supported by Science and Technology Project of Hebei Education Department (No. ZD2022128)Tangshan Science and Technology Plan Project (No. 22130226H)。
文摘In this paper,the effect of vibration intensity on the spatial distribution of sulfur content in bed particles was studied.The effects of vibration and airflow on the mechanical characteristics of particles were studied,the collision behavior mode of particles was determined,the spatial saltation law of particles was investigated,the spatial functional axis of beds was determined,and the saltation separation period of particles was determined.The test results show that:When separation bed provides inlet airflow velocity(U_(in)) is 2.55 m/s,the airflow distribution interval of I,II and III areas were U_(I)=2.55-2.57 m/s,U_(II)=1.33-1.35 m/s,U_(III)=0.35-0.38 m/s,respectively;when separation bed vibration amplitude (A)A=2.4-2.5 mm,separation bed vibration frequency (f) f=23-24 Hz,the desulfurization effect is the best.When vibration intensity (Γ)Γ=1.22,U_(in)=1.05 m/s,the particles have disordered contact and collision behavior.WhenΓ=14.89,U_(in)=3.18 m/s,the particles have a transition cataclastic collision.WhenΓ=5.80,U_(in)=2.55 m/s,the particles have directional collision behavior.It is determined that the OX axis is the transverse stable diffusion axis of the material,the OY axis is the longitudinal gradient transport axis of the material,and the OZ axis is the vertical density cascade distribution axis of the material.When separation time (T) T=0-10 s was the period of disorderly diffusion and mixing of particles,T=10-20 s was the period of directional migration and stratification of particles,and T=20-30 s was the period of cascade distribution and separation of particles.Finally,separation experiments conducted under optimal operating parameters demonstrated that the clean coal yield was 72.02%with a sulfur content of 0.98%.
基金Under the auspices of the National Key Research and Development Program of China(No.2022YFD1500501)the Innovation Team Project of Northeast Institute of Geography and Agroecology,Chinese Academy of Sciences(No.2023CXTD02)+2 种基金the National Natural Science Foundation of China(No.41971066)the Key Laboratory Foundation of Mollisols Agroecology(No.2020ZKHT-03)the High Tech Fund Project of S&T Cooperation between Jilin Province and Chinese Academy of Sciences(No.2022SYHZ0018)。
文摘Water scarcity and soil salinization pose significant challenges to agriculture in the West Liaohe Plain,eastern Inner Mongolia,China.Shallow-buried drip irrigation can improve soil water use efficiency to alleviate water shortage in agriculture and the application of lignite humic acid reduces the adverse effects of soil salinization.However,further research is needed to investigate the effects of different application rates of lignite humic acid and humic acid-based combined amendment on soil physicochemical properties,nutrient contents,and crop yield in saline-sodic farmlands under shallow-buried drip irrigation.A two-year field experiment was conducted with control without any amendment(CK),three treatments amended with 3 t/ha(H1),6 t/ha(H2),and 12 t/ha(H3)lignite humic acid,and three application rates with 15 t/ha(T1),22.5 t/ha(T2),and 30 t/ha(T3)lignite humic acid-based combined amendment in 2021 and2022.The results showed that H3 reduced soil bulk density,p H,electrical conductivity,and total alkalinity,while increasing the contents of soil organic matter,total nitrogen,and available potassium in the two-year experiment.Moreover,the maize yield in H3 increased by an average of 35.5%.T2 decreased soil bulk density,p H,total alkalinity,and increased maize yield by 16.2%,compared to the first year.These results suggest that T2 consistently improved both soil quality and crop yield.Correlation analyses showed that lignite humic acid and its complexes promote maize growth and increase yield by increasing soil organic matter and total nitrogen while reducing soil salinity and total alkalinity.Based on the comprehensive analysis of the field data and the results of the comprehensive evaluation of soil quality,it was determined that the appropriate improvement measures for saline-sodic farmlands under shallow-buried drip irrigation are the application of 12 t/ha of lignite humic acid and 22.5 t/ha of lignite humic acid-based combined amendment.This study demonstrates the effectiveness of lignite humic acid and its combined amendment in mitigating the constraints of saline-sodic farmlands and enhancing crop yields,providing a sustainable solution for improving saline-sodic farmlands in the West Liaohe Plain.
基金the National Natural Science Foundation of China(nos.21968022 and 51962027)the Fundamental Research Funds for Inner Mongolia University of Science&Technology(no.2023QNJS052)the Natural Science Foundation of Inner Mongolia(no.2019BS02002)
文摘Silicon oxide(SiO_(x),0<x≤2)has been recognized as a prominent anode material in lithium-ion batteries and sodium-ion batteries due to its high theoretical capacity,suitable electrochemical potential,and earth abundance.However,it is intrinsically poor electronic conductivity and excessive volume expansion during potassiation/depotassiation process hinder its application in potassium-ion batteries.Herein,we reported a hierarchical porous C/SiO_(x)potassium-ion batteries anode using lignite as raw material via a one-step carbonization and activation method.The amorphous C skeleton around SiO_(x)particles can effectively buffer the volume expansion,and improve the ionic/electronic conductivity and structural integrity,achieving outstanding rate capability and cyclability.As expected,the obtained C/SiO_(x)composite delivers a superb specific capacity of 370 mAh g^(-1)at 0.1 A g^(-1)after 100 cycles as well as a highly reversible capacity of 208 mAh g^(-1)after 1200 cycles at 1.0 A g^(-1).Moreover,the potassium ion storage mechanism of C/SiO_(x)electrodes was investigated by ex-situ X-ray diffraction and transmission electron microscopy,revealing the formation of reversible products of K_(6.8)Si_(45.3)and K_(4)SiO_(4),accompanied by generation of irreversible K2O after the first cycle.This work sheds light on designing low-cost Si-based anode materials for high-performance potassium-ion batteries and beyond.
文摘Biogasification of coal is important for clean utilization of coal. Experiments on the fermentation of single lignite, single straw and their mixture were performed to explore the variation characteristics of gas production potential, microbial community and methanogenic metabolic pathways of mixture. Research has shown that mixed fermentation of lignite and straw significantly promoted biomethane production. The abundance of hydrolytic acidifying functional bacteria genera (Sphaerochaeta, Lentimicrobium) in mixed fermentation was higher than that in the fermentation of single lignite and single straw. The abundance of some key CAZy metabolic enzyme gene sequences in mixed fermentation group was increased, which was favorable to improve methane production. Aceticlastic methanogenesis was the most critical methanogenic pathway and acetic acid pathway was more competitive in methanogenic mode during peak fermentation. Macrogenomics provided theoretical support for the claim that mixed fermentation of coal and straw promoted biomethane metabolism, which was potentially valuable in expanding methanogenesis from mixed fermentation of lignite with different biomasses.
文摘To enhance methane production efficiency in lignite anaerobic digestion and explore new ways for residual sludge utilization, this study employed the co-fermentation of lignite and residual sludge for biomethane conversion. The bacterial colony structure, metabolic pathways, and interactions between residual sludge and lignite in anaerobic methanogenic fermentation with different mass ratios were analyzed using macrogenomics sequencing. This study aimed to explore the mechanisms involved in the co-anaerobic fermentation of lignite and residual sludge. The results indicated that the addition of sludge enhanced the metabolic pathways in hydrolysis acidification, hydrogen-acetic acid production, and methanation phases. Notably, the enhancement of acetate- and carbon dioxide-nutrient metabolic pathways was more pronounced, with increased activity observed in related enzymes such as acetic acid kinase (k00925) and acetyl coenzyme synthetase (K01895). This increased enzymatic activity facilitated the microbial conversion of biomethane. The results of the study indicated that the sludge exhibited a promotional effect on the methane produced through the anaerobic fermentation of lignite, providing valuable insights for lignite and residual sludge resource utilization.
文摘The paper presents the change in grain-size composition of lignite under cyclic freezing-thawing (FTC) and wetting-drying (WDC). The article shows that in the spring and autumn periods the lignites can be subjected to repeated freezing-thawing and wetting-drying, which determines the possibility of changing their grain-size composition and structure. Experimental studies in laboratory conditions on the influence of cyclic freezing-thawing (FTC) and wetting-drying (WDC) on the quality indicators of lignites have been carried out, their granulometric (fractional) composition has been studied. Freezing-thawing cycle conditions are as follows (FTC): minimum exposure temperature: -20°C;maximum: +5°C;relative humidity: 30%;number of processing cycles: 3. Wetting-drying cycles are as follows (WDC): drying temperatures are +20, +40, +60, +80°C, drying time 90 minutes, the coals are further subjected to rain (soaking) for a period of water saturation to humidity of 30% - 40% and dry again. The number of wetting-drying cycles is 3 times. The tests have revealed the destructive effects of FTC and WDC on the samples of lower metamorphic grade coal, and the cycles of wet-dry lead to the much higher yield of fine sizes (-6+0;-13+0 mm) than the cycles of freeze-thaw. Furthermore, it is found that the increase in the yield of fines depends on the heating temperature: coal disintegration proceeds more intensively at a higher temperature of drying.
基金supported by the National Natural Science Foundation of China (No. 21006059)the Project of Shandong Province Higher Educational Science and Technology Program (No. J11LB61)
文摘The adsorption characteristics of virgin and potassium permanganate modified lignite semi-coke (SC) for gaseous Hg were investigated in an attempt to produce more effective and lower price adsorbents for the control of elemental mercury emission. Brunauer-Emmett- Teller (BET) measurements, X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were used to analyze the surface physical and chemical properties of SC, Mn-SC and Mn-H-SC before and after mercury adsorption. The results indicated that potassium permanganate modification had significant influence on the properties of semi-coke, such as the specific surface area, pore structure and surface chemical functional groups. The mercury adsorption efficiency of modified semi-coke was lower than that of SC at low temperature, but much higher at high temperature. Amorphous Mn7+, Mn6+ and Mn4+ on the surface of Mn-SC and Mn-H-SC were the active sites for oxidation and adsorption of gaseous Hg~, which oxidized the elemental mercury into Hg2+ and captured it. Thermal treatment reduced the average oxidation degree of Mn2+ on the surface of Mn-SC from 3.80 to 3.46. However, due to the formation of amorphous MnOx, the surface oxidation active sites for gaseous Hg0 increased, which gave Mn-H-SC higher mercury adsorption efficiency than that of Mn-SC at high temperature.
文摘The process of lignite desulphurization via its treatment by an oxidant(air or air–steam mixture)has been studied.The research objective was useful determination of steam application in oxidative lignite desulphurization.It has been proved that the water steam should be included in the oxidant composition to increase the hydrogen sulphide and combustible constituent content in the gases obtained during the processes under research.The impact of factors which affect the reactions between solid(in our case–lignite)and gaseous reagent(oxidant,i.e.air and or air–steam mixture)upon the research process has been investigated,if these reactions occur in the kinetic area.Such factors are linear rate of oxidant movement and coal grain size.The values of oxidant movement linear rate and coal grain size,which the reaction transfer from pyrite sulphur and organic content of lignite from diffusion into kinetic area occurs by,have been determined.Under these‘‘transfer’’conditions,the values of coefficients of oxidant mass transfer(β,m/s)as well as Sherwood criteria and boiling layer differences have been calculated.
基金Projects 50874107 and 50374068 supported by the National Natural Science Foundation of ChinaCPEUKF06-12 by the Foundation of Key Laboratoryof Coal Processing & Efficient Utilization, Ministry of Education of China
文摘Lignite bio-solubilization is a promising technology for converting solid lignite into oil.This study concerns the adsorption of lignite-solubilizing enzymes onto the lignite surface.Adsorption capacity, infrared spectral analysis and driving forces analysis are studied as a way to help understand the bio-solubilization mechanism.The results show that the amount of lignite bio-solubilization is proportional to the amount of adsorbed lignite-solubilizing enzymes.An increase in lignite-solubilizing enzyme adsorption of 10% leads to a 7% increase in lignite bio-solubilization.However, limited amounts of enzymes can be adsorbed by the lignite, thus resulting in low percentages of bio-solubilization.Infrared spectral analysis shows that side chains, such as hy-droxyl and carbonyl, of the lignite structure are the main, and necessary, structures where lignite-solubilizing enzymes attachto the lignite.Furthermore, driving force analysis indicates that the electrostatic force between lignite and enzymes is the main adsorption mechanism.The forces are influenced by solution pH levels, the zeta potential of the lignite and the isoelectric points of the en-zymes.
基金Projects 50874107 and 50374068 supported by the National Natural Science Foundation of ChinaCPEUKF06-12 by the Foundation of Key Laboratory of Coal Processing & Efficient Utilization, Ministry of Education of China
文摘A white rot fungus strain, Trichoderma sp.AH, was isolated from rotten wood in Fushun and used to study the mechanism of lignite bio-solubilization.The results showed that nitric acid pretreated Fushun lignite was solubilized by T.sp.AH and that extracellular proteins from T.sp.AH were correlated with the lignite bio-solubilization results.In the presence of Fushun lignite the extracellular protein concentration from T.sp.AH was 4.5 g/L while the concentration was 3 g/L in the absence of Fushun lignite.Sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE) of the extracellular proteins detected at least four new protein bands after the T.sp.AH had solubilized the lignite.Enzyme color reactions showed that extracellular proteins from T.sp.AH mainly consisted of phenol-oxidases, but that lignin decomposition enzymes such as laccase, peroxidase and manganese peroxidases were not present.
基金Supported by the National Natural Science Foundation of China(51621005)the Fundamental Research Funds for the Central Universities(2017FZA4013)
文摘The surface functional groups and pyrolysis characteristics of lignite irradiated by microwave were comparatively studied to evaluate the feasibility of using industrial 915 MHz for lignite drying. The drying kinetics, micro structure, chemical functional groups, re-adsorption properties, and pyrolysis characteristics of the dried coal were respectively analyzed. Results indicated that for typical Chinese lignite studied in this paper, 915 MHz microwave drying was 7.8 times faster than that of the hot air drying. After industrial microwave drying, the sample possessed much higher total specific surface area and specific pore volume than that of air dried sample. The oxygen functional groups and re-adsorption ratio of microwave irradiated coal decreased, showing weakened hydrophilicity. Moreover, during the pyrolysis of the coal dried by hot air and microwave, the yield of tar largely increased from 1.3% to 8.5% and the gas production increased correspondingly. The composition of the tar was also furtherly analyzed, results indicated that Miscellaneous hydrocarbons(HCs) were the main component of the tar, and microwave irradiation can reduce the fraction of polycyclic aromatic hydrocarbons(PAHs) from 26.4% to 22.7%.
基金Supported by the Fundamental Research Funds for the Central Universities (2010ZY42)the Open Foundation of National Laboratory of Mineral Materials of China University of Geosciences (08A003)
文摘The feasibility and adsorption effect of lignite activated carbon for phenol removal from aqueous solutions were evaluated and investigated. A series of tests were performed to look into the influence of various experimental parameters such as contact time, initial phenol concentration, temperature, and pH value on the adsorption of phenol by lignite activated carbon. The experimental data were fitted well with the pseudo-second-order kinetic model. The adsorption is an endothermic process and conforms to Freundlich thermodynamic model. The results indicate that the lignite activated carbon is suitable to be used as an adsorbent material for adsorption of phenol from aqueous solutions.
文摘A process of recovering Ge by chlorinating masting was put forward. GeCl4 was separated and recovered from lignite ash because of its low boiling point. Kinetic analysis indicates that the chlorinating roasting process fits with the unreacted-core shrinking model and the reaction rate equation corresponds to 1 - 2a/3 - (1 - a)2/3 = kt. The apparent activation energy Ea is calculated to be 22.36 kJ·mol^-1. The diffusion of product layer serves as the rate-controlling step in this process. When the roasting temperature is 250℃, the roasting time is 60 min, the con- centration of hydrochloric acid is 10 mol/L, and the ratio of liquid to solid is 10 (mHCl/ash = 10), and 90% Ge in lignite ash can be recovered.
文摘The distribution and verticals variation of geochemical components in the Kasnau-Matasukh lignites of Nagaur Basin, Rajasthan, were investigated using microscopy, proximate and ultimate analyses, Rock-Eval Pyrolysis, X-ray diffraction and Fourier Transform Infrared analyses, and major/minor/trace element determination. The relationship of elements with ash content and with macerals have also been discussed. These lignites are stratified, black, dominantly composed of huminite group macerals with subordinated amounts of liptinite and inertinite groups. They are classified as type-III kerogen and are mainly gas prone in nature. The concentration (in vol%) of mineral matter is seen to increase towards upper part of seam and so is the concentration (in wt%) of the volatile matter, elemental carbon and sulphur. The common minerals present in these lignitesare mixed clay layer, chlorite, and quartz as identified by X-ray diffraction study. Compared with world average in brown coal, the bulk concentration of Cu is anomalously high in most of the samples while Cd is 2-3 times high and Zn is high in one band. Based on interrelationship, different pyrite forms are noticed to have different preferential enrichment of various elements. The concentration of disseminated pyrite is more than the other pyrite forms and is followed by discrete pyrite grains and massive pyrite.
基金Supported by the National Natural Science Foundation of China(51704292,51774285)the China Postdoctoral Science Foundation(2016M601919)+1 种基金the National Key R&D Program of China(2016YFB0600401)the Fundamental Research Funds for the Central Universities(2017QNA25,CPEUKF1704)
文摘The drying processes are always applied prior to the transportation or utilization of lignite, and result in notable changes in the stabilities of lignite. In this paper, the study on the effects of nitrogen and MTE drying process on the physico-chemical properties and stabilities of Zhaotung lignite was carried out. The briquettes produced by MTE drying in this study were 150 mm in dimension, and so had a much larger particle size than nitrogen- dried samples. Nitrogen adsorption, mercury intrusion porosimetry and scanning electron microscopy all suggested that drying was accompanied by the transformation of larger pores into smaller ones. Compared to nitrogen drying, the pore structures could be stabilized by the MTE process. The soluble salts were removed during MTE drying which resulted in the decrease in ash and the concentrations of some of the major metals. The removal of water enhanced the hydrophilicity of nitrogen dried samples, but did not affect the hydrophilicity of MTE dried samples. The moisture holding capacity of MTE dried samples reduced faster than nitrogen dried samples with the decrease of residual moisture content. The moisture readsorption processes of MTE dried sam- ples were strongly inhibited due to the much larger particle size of sample produced by MTE drying than nitrogen drying. The susceptibility to spontaneous combustion, indicated by cross point temperature and self-heating tests, of nitrogen and MTE dried samples increased with the decrease of residual moisture content. The MTE dried samples are more liable to spontaneous combustion than nitrogen dried samples with the same residual moisture and particle size. However, the larger particle size of the MTE product made it more stable with respect to spontaneous combustion and also moisture readsorption.
文摘Lignite samples collected from Vastan, Rajpardi and Tadkeshwar lignite mines of Cambay basin (Gujarat) were subjected to organic petrographic investigations and geochemical analyses and the data, thus generated, is used to reconstruct the paleodepositional history of these lignite sequences. The lignites of Cambay basin dominantly comprise huminite maceral group (71.6%-86.3%) followed by liptinite (10.1%-19.3%) and inertinite (3.6%-11.0%) maceral groups. The mineral matter varies from 9.0% to 20.0%. The petrography based facies model indicates that these lignites have high values of gelification index (GI) and low tissue preservation index revealing a continuous wet condition in the basin and a relatively slower rate of subsidence during the decay of organic matter. On several occasions, during the formation of seams in Tadkeshwar, Rajpardi and Vastan mines, the value of GI exceeded 10 which indicates a forest permanently flooded and the cause of pronounced degree of degradation. However, few sections in Tadkeshwar seam had relatively drier spells of environmental conditions due to fluctuation in the water table as revealed by moderately high content of inertinite macerals. This is specially indicated by the occurrence of funginite which normally thrives in the upper oxy- genated peatigenic layer and indicates prevalence of oxic conditions during plant deposition. Such conditions prevailed during a transgressive phase but there were intermittent fluvial activities also giving rise to supratidal flood plain as reflected in the form of associated carbonaceous shales in the basin.
基金Supported by the Key Project of Joint Fund from National Natural Science Foundation of China and the Government of Xinjiang Uygur Autonomous Region(U1503293)the National Key Research and Development Program of China(2018YFB0604602)the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Soluble portions(SPs) 1-4(SP1-SP4) were afforded from sequentially dissolution and alkanolyses of Baiyinhua lignite(BL) in cyclohexane,CH3OH,CH3CH2OH,and(CH3)2CHOH at 300℃.They were analyzed with a gas chromatograph/mass spectrometer and quadrupole exactive orbitrap mass spectrometer(QEOTMS) with an atmosphere pressure chemical ionization source in positive-ion mode,while BL was characterized with an X-ray photoelectron spectrometer(XRPES).The results show that the yields of SP2 and SP3 are much higher than those of SP1 and SP4,and the total SP yield is ca.39.0%.According to the analysis with XRPES,pyrrolic nitrogen atoms are the most abundant nitrogen existing forms in BL.Thousands of nitrogen-containing aromatics(NCAs) were resolved with QEOTMS and their molecular masses are mainly in the range of 200-450 u.The main NCAs are N1O1 and N1O2 class species with double bond equivalent values of 4-18 and carbon numbers of 7-30.The nitrogen atoms appear in pyridine s,quinolines,benzoquinolines or acridine,and dibenzoquinolines or naphthoquinolines,while the oxygen atoms exist in methoxy and furan rings.
基金supported by the National Basic Research Program of China(2012CB723105)the National Natural Science Foundation of China(20976117)Shanxi Graduates Excellent Innovation Project of China(tyut-rc201018a)
文摘With lignite after vacuum drying as the raw material,a series of Zn-based sorbents were prepared by static impregnation,ultrasonic-assisted impregnation,bubbling-assisted impregnation and high-pressure impregnation.The physical properties and the desulfurization performances of Zn-based sorbents were studied systematically by XRD,BET,AAS characterization techniques and the fixed-bed desulfurization evaluation apparatus.The sorbents obtained by high-pressure impregnation method have a larger specific surface area,pore volume and pore diameter comparing with other methods,which is conducive to the sulfidation reaction of hydrogen sulfide gas in the sorbent.The effects of pressure during the high-pressure impregnation and concentration of Zn(NO3)2 precursor solution on the sorbents properties and desulfurization behavior were investigated.The higher the impregnation pressure and the concentration of impregnation solution are,the greater the amount of the active components are uploaded.However,overhigh impregnation pressure can cause collapse and blocking of the carrier pore.The optimal operating condition of high-pressure impregnation method for preparing the sorbents was the impregnation pressure of 20 atm and the solution concentration of 41%.Under that condition,the sorbent had the best desulfurization ability with a sulfur capacity of 13.94 gS/100 gsorbent and a breakthrough time of 54 h.Its desulfurization precision and efficiency of removing H2S before sorbent breakthrough from the middle temperature gases of 400℃ can reach【5 ppm and】99%,respectively.Sorbents could be regenerated under the condition of 1 vol%O2,20 vol% H2O,0.5 vol% NH3,and N2balance gas.The regenerated sorbent could be used for repeated absorption of H2S with a slight decrease in desulfurization effect.