Comparison of Optimization Schemes for the Flue Gas Purification System of a Garbage Incineration Power Plant

A garbage incineration power plant is proposed to be built somewhere. Due to local environmental capacity and local policy,the demand on the flue gas emission indicators of the project is high,but the conventional purification process of flue gas produced during waste incineration（ SNCR denitrification ＋dry/semi-dry deacidification ＋ adsorption of dioxins and heavy metals by activated carbon ＋ bag dusting） has been unable to meet this requirement,and the newly added wet deacidification and SCR denitrification processes can meet this requirement. The flue gas purification process was optimized,and two feasible schemes were compared to choose the better one.

Pollutant Sources and Foaming Control Measures of Decarbonization Solution in Natural Gas Purification Plant

Yanbei project of Schlumberger Copower Oilfield Engineering Co.,Ltd.-natural gas purification plant decarbonization unit is equipped with two sets of decarbonization systems(parallel operation).The two sets of systems adopt two tower process,full lean liquid circulation regeneration process,one tower absorption(absorption pressure 5.4mpag),one tower regeneration(regeneration temperature 95℃-110℃),purified natural gas carbon dioxide content≤2.5vol%,single set The treatment capacity is 2300 KM3/d.This paper introduces the problems existing in the decarbonization solution of the decarbonization unit in the natural gas purification plant in recent three years,analyzes the causes of pollutants affecting the quality of the decarbonization solution,and probes into the control measures for the pollution of the decarbonization solution,so as to provide reference.

Studies on Oxygen Characteristics of YBa_2Cu_3O_(7-x) and Its Applications to Air Separation and Gas Purification

Oxygen diffusion and oxygen selective adsorption properties of rare earths material YBa_2Cu_3O_(7-x) (YBCO) were investigated by thermogravimetric, oxygen static adsorption and selectivity adsorption experiments. The results show that YBCO is a very good deoxidizing material. The oxygen desorption of YBCO begins remarkably at about 400 ℃, mass loss can arrive at 1.2% of its original quantity at 800 ℃. Oxygen can be completely absorbed back into the sample again when temperature descends to 400 ℃. The oxygen adsorption selectivity, reproducibility and oxygen adsorption under very low oxygen partial pressure make the material desirable for air separation and gas purification. High purity nitrogen gas was produced with the YBCO molecular sieves in the air separation and gas purification experiments. 0.017 m^3 of high purity nitrogen (>99.9999%) can be obtained with 1 kg YBCO molecular sieve in one cycle. As a deoxidant, an obvious advantage of YBCO is that no hydrogen is needed in its applications.

A Scalable Pillar Layered Metal-Organic Framework for Natural Gas Purification

One-step harvest of high-purity methane(CH_(4))from ternary propane/ethane/methane(C_(3)H_(8)/C_(2)H_(6)/CH_(4))mixtures remains a desirable yet challenging goal for natural gas purification.However,adsorbents either suffer from high capacity and selectivity,or are caught in a dilemma of scalable synthesis.Herein,we demonstrate a scalable pillar layered metal-organic framework Ni-MOF for highly efficient one-step CH_(4)purification.Ni-MOF exhibits high C_(2)H_(6)and C_(3)H_(8)uptakes of 83.3 and 86.1 cm^(3)/g at 298 K and 100 kPa and remarkable C_(2)H_(6)/CH_(4)(50/50,volume ratio,21.5)and C_(3)H_(8)/CH_(4)(50/50,volume ratio,212.0)selectivities.Notably,high C_(2)H_(6)(42.2 cm^(3)/g at 10 kPa)and C_(3)H_(8)(64.7 cm^(3)/g at 5 kPa)capacities in the low-pressure region at 298 K were realized on Ni-MOF,suggesting the strong affinities of Ni-MOF towards C_(2)H_(6)and C_(3)H_(8).Furthermore,the dynamic breakthrough experiments revealed that purifying CH_(4)from natural gas in one-step can be achieved in Ni-MOF with high-purity(>99.8%)and productivity(346.0 cm^(3)/g).Most significantly,the production of Ni-MOF can be scalably synthesized at room temperature,rendering it promising potential for industrial application.The combined advantages of exceptional separation performance,scalability,and cycle stability of Ni-MOF pave the way for one-step CH_(4)purification from natural gas.

面向未来低碳道路养护的超薄罩面功能性研究综述

Highway maintenance mileage reached 5.25 million kilometers in China by 2021.Ultra-thin overlay is one of the most commonly used maintenance technologies,which can significantly enhance the economic and environmental benefits of pavements.To promote the low-carbon development of ultrathin overlays,this paper mainly studied the mechanism and influencing factors of several ultra-thin overlay functions.Firstly,the skid resistance,noise reduction,rutting resistance,and crack resistance of ultrathin overlays were evaluated.The results indicated that the high-quality aggregates improved the skid and rutting resistance of ultra-thin overlay by 5%-20%.The optimized gradations and modified binders reduced noise of ultra-thin overlay by 0.4-6.0 dB.The high viscosity modified binders improved the rutting resistance of ultra-thin overlay by about 10%-130%.Basalt fiber improved the cracking resistance of ultra-thin overlay by more than 20%.Due to the thinner thickness and better road performance,the performance-based engineering cost of ultra-thin overlay was reduced by about 30%-40%compared with conventional overlays.Secondly,several environmentally friendly functions of ultra-thin overlay were investigated,including snow melting and deicing,exhaust gas purification and pavement cooling.The lower thickness of ultra-thin overlay was conducive to the diffusion of chloride-based materials to the pavement surface.Therefore,the snow melting effect of self-ice-melting was better.In addition,the ultra-thin overlay mixture containing photocatalytic materials could decompose 20%-50%of the exhaust gas.The colored ultra-thin overlay was able to reduce the temperature of the pavement by up to 8.1℃.The temperature difference between the upper and lower surfaces of the ultra-thin overlay containing thermal resistance materials could reach up to 12.8℃.In addition,numerous typical global engineering applications of functional ultra-thin overlay were summarized.This review can help better understand the functionality of ultra-thin overlays and promote the realization of future multi-functional and low-carbon road maintenance.

Study on Pressure Swing Adsorption Removing C_(2)^(+) from Natural Gas as Raw Material for Thermal Chlorination

The experimental investigation demonstrates that a satisfactory result can be expected for pressure swing adsorption (PSA) purification of natural gas as raw material for thermal chlorination process. Using hh-4 molecular sieve as adsorbent for removing C+2 components, the suitable adsorption pressure is 0.4-0.45 MPa, desorption vacuum is 0.08-0.09 MPa and circulation time is 20-21 min.

An Adsorption Kinetic Model for Sulfur Dioxide Adsorption by ZL50 Activated Carbon

A semi-empirical adsorption kinetic model was proposed with the time compensation method to describe the chemisorption of SO2 in flue gas by carbon adsorbents for flue gas purification.The change in adsorption capacity and adsorption rate with time at different water vapor concentrations and different SO2 concentrations was studied.The model was in good agreement with experimental data.The surface reaction was probably the rate controlling step in the early stage for SO2 adsorption by ZL50 activated carbon.The parameters m and n in the nth order adsorption kinetic model were related to the magnitude of the time compensation and adsorption driving force,respectively.The change of parameter n with water vapor concentrations and sulfur dioxide concentrations was studied and some physical implications were given.The sum of square errors was less than 1.0 and the average absolute percentage deviations ranged from 0.5 to 3.2.The kinetic model was compared with other models in the literature.

High-performance SSZ-13 membranes prepared using ball-milled nanosized seeds for carbon dioxide and nitrogen separations from methane

SSZ-13 membranes with high separation performances were prepared using ball-milled nanosized seeds by once hydrothermal synthesis.Separation performances of SSZ-13 membranes in CO2/CH4 and N2/CH4 mixtures were enhanced after synthesis modification.Single-gas permeances of CO2,N2 and CH4 and ideal selectivities were recorded through SSZ-13 membranes.The effects of temperature,pressure,feed flow rate and humidity on separation performance of the membranes were discussed.Three membranes prepared after synthesis modifications had an average CO2 permeance of 1.16×10-6 mol·(m2·s·Pa)-1(equal to 3554 GPU)with an average CO2/CH4 selectivity of 213 in a 50 vol%/50 vol%CO2/CH4 mixture.It suggests that membrane synthesis has a good reproducible.The membrane also displayed a N2 permeance of 1.07×10-7 mol·(m2·s·Pa)-1(equal to 320 GPU)with a N2/CH4 selectivity of 13 for a 50 vol%/50 vol%N2/CH4 mixture.SSZ-13 membrane displayed stable and good separation performance in the wet CO2/CH4 mixture for a long test period over 100 h at 348 K.The current SSZ-13 membranes show great potentials for the simultaneous removals of CO2 and N2 in natural gas purification as a facile process suitable for industrial application.

A novel purification technique for noble gas isotope analyses of authigenic minerals

Noble and active gases are released from geological samples during gas extraction for noble gas isotope analyses. The active gases should be removed before inletting to mass spectrometers for the analyses. The normal noble gas preparation systems can clean up most geological samples. However, authigenic minerals from sedimentary rocks in oil/gas fields contain organic matter, which cannot be cleaned up by the normal preparation systems and thus influence the noble gas analyses. We introduce a novel gas purification system （PRC patent No. ZL201320117751.2）, which includes several reversible purification pumps with different absorbing and degassing temperatures. It can well clean up water steam, carbon dioxide and organic gas- es. Mica minerals are often used for 40Ar/39Ar dating. A muscovite sample （2082MS） which could not be cleaned up by the normal preparation system with two SAES NP10 getters, becomes the test sample for a comparative experiment in this study. The experiment is assigned into 4 sections with the organic gas removal system （OGRS） ＂Closed/Opened＂ in turn. When the OGRS is closed only with two NP10 getters for purification, the 40At intensities increase in curves with inlet time because of impurities, the 40Ar/39Ar dating results yield age errors about ＋2%-±1% （20-）. When the OGRS is opened for purification, in contrast, the 40Ar intensities decrease linearly with inlet time. This indicates that the gases have been cleaned up effectively, and the 40Ar/39Ar results yield ages with errors in ±0.4%. The OGRS is very helpful to obtain high-quality analysis data.

The Performance Study on Adsorption of SO2 of CuO Modifying 13X Zeolite Molecular Sieve

Research and development of efficient, economical and resource-based flue gas desulfurization technology has always been a hot spot in the field of air pollution control. Molecular sieve materials have been paid attention to by SO2 adsorbent researchers due to their huge specific surface area. In this paper, 13X zeolite was modified with Cu(NO3) 2·3H2O to obtain 13x-Xwt %CuO (calculated by the amount of CuO loaded). The adsorption time and capacity of SO2 penetration sorbent and the isothermal curve of N2 adsorption-desorption were studied. The results are as follows: 13X-3wt%CuO has the best adsorption effect, the penetration adsorption time is 110 min, the penetration adsorption capacity is 43.41 mg·g-1, the saturation adsorption capacity is 49.27 mg·g-1;The amount of CuO loading has a great influence on the adsorption effect of modified 13X molecular sieve on SO2. SEM and BET characterization showed that CuO modification did not change the external morphology of 13X molecular sieve, changed the pore size, but did not block the original channel of the molecular sieve, before and after modification belong to the type I adsorption isothermal curve. The pore size distribution and type of molecular sieve, as well as the content and type of alkali metal cations jointly control the adsorption process of SO2 by 13X-xwt %CuO. XPS characterization showed that Cu(NO3) 2 decomposed into CuO and Cu2O during roasting at 450°C, CuO/Cu2O ≈ 1.5. The R2 values of the quasi-second-order kinetic models obtained from the 13X-Xwt %CuO particle diffusion kinetic models were all above 0.99, indicating that the quasi-second-order kinetic equations were more relevant. Particle diffusion dynamics model in fitting results show that the adsorption process can be divided into two stages, the first phase of surface adsorption and diffusion rate in the granules common control process, more accurate dynamics model of the secondary in the second phase particle diffusion rate control stage, mainly for the micropore adsorption or chemical adsorption, quasi level 2 dynamic model conformity of variation;C is a constant not equal to 0, indicating that the adsorption of SO2 is not completely through the form of intra-particle diffusion, and a small amount of chemisorption exists. And it is the compound effect of multiple adsorption mechanisms.

Boosting selective C_(2)H_(2)/CH_(4),C_(2)H_(4)/CH_(4) and CO_(2)/CH_(4) adsorption performance via 1,2,3-triazole functionalized triazine-based porous organic polymers

Nitrogen-rich porous organic polymers have shown great potentials in gas adsorption/separation,photocatalysis,electrochemistry,sensing and so on.Herein,1,2,3-triazole functionalized triazine-based porous organic polymers(TT-POPs)have been synthesized by the copper-catalyzed azide-alkyne cycloaddition(Cu-AAC)polymerization reactions of 1,3,5-tris(4-azidophenyl)-triazine with 1,4-diacetylene benzene and 1,3,5-triacetylenebenzene,respectively.The characterizations of N2 adsorption at 77 K show TTPOPs possess permanent porosity with BET surface areas of 666 m^(2)·g^(-1)(TT-POP-1)and 406 m^(2)·g^(-1)(TT-POP-2).The adsorption capacities of TT-POPs for CO_(2),CH4,C2H2 and C2H4,as well as the selective separation abilities of CO_(2)/N2,CO_(2)/CH_(4),C_(2)H_(2)/CH_(4) and C_(2)H_(4)/CH_(4) were evaluated.The gas selective separation ratio of TT-POPs was calculated by the ideal adsorbed solution theory(IAST)method,wherein the selective separation ratios of C_(2)H_(2)/CH_(4) and C_(2)H_(4)/CH_(4) of TT-POP-2 was 48.4 and 13.6(298 K,0.1 MPa),which is comparable to other adsorbents(5.6–120.6 for C_(2)H_(2)/CH_(4),10–26 for C_(2)H_(4)/CH_(4)).This work shows that the 1,2,3-triazole functionalized triazine-based porous organic polymer has a good application prospect in natural gas purification.

Systematic control technologies for gaseous pollutants from non-ferrous metallurgy

Air pollutant emissions represent a critical challenge in the green development of the non-ferrous metallurgy industry.This work studied the emission characteristics,formation mechanisms,phase transformation and separation of typical air pollutants,such as heavy metal particles,mercury,sulfur oxides and fluoride,during non-ferrous smelting.A series of purification technologies,including optimization of the furnace throat and hightemperature discharge,were developed to collaboratively control and recover fine particles from the flue gas of heavy metal smelting processes,including copper,lead and zinc.Significant improvements have been realized in wet scrubbing technology for removing mercury,fluoride and SO_(2)from flue gas.Gas-liquid sulfidation technology by applying H_(2)S was invented to recycle the acid scrubbing wastewater more efficiently and in an eco-friendly manner.Based on digital technology,a source reduction method was designed for sulfur and fluoride control during the whole aluminum electrolysis process.New desulfurization technologies were developed for catalytic reduction of the sulfur content in petroleum coke at low temperature and catalytic reduction of SO_(2)to elemental sulfur.This work has established the technology for coupling multi-pollutant control and resource recovery from the flue gas from non-ferrous metallurgy,which provides the scientific theoretical basis and application technology for the treatment of air pollutants in the non-ferrous metallurgy industry.

Fluorinated metal-organic framework for methane purification from a ternary CH_(4)/C_(2)H_(6)/C_(3)H_(8)mixture

Herein we present a fluorinated metal-organic framework of{(Me_(2)NH_(2))[Ni_(3)(μ_(3)-OH)(CF_(3)-BPDC-CF_(3))_(3)(tpt)]}_(n)(1)constructed from 2,2'-bis(trifluoromethyl)biphenyl-4,4'-dicarboxylic(CF_(3)-BPDC-CF_(3)^(2-))and 2,4,6-tri(4-pyridyl)-1,3,5-triazine(tpt)ligands,which is developed for separating propane(C_(3)H_(8))and ethane(C_(2)H_(6))from natural gas.Compound 1 preferentially adsorbs C_(3)H_(8)and C_(2)H_(6)over CH_(4)demonstrated by gas adsorption experiments.The presence of trifluoromethyl groups on the biphenyl-4,4'-dicarboxylic ligands facilitates the highly polarized micropore environments for compound 1,thus providing suitable micorpores for capturing the C_(3)H_(8)and C_(2)H_(6)molecules with larger polarizabilities and sizes compared to CH_(4)molecule.The dynamic mixture breakthrough experiments showed that compound 1 can separate C_(3)H_(8)and C_(2)H_(6)from the ternary CH_(4)/C_(2)H_(6)/C_(3)H_(8)mixtures efficiently,endowing compound 1 with excellent methane purification ability.

Recent advances in nanoporous graphene membrane for gas separation and water purification

Graphene is a one-atom-thick sheet of graphite comprising sp2-hybridized carbon atoms arranged in the hexagonal honeycomb lattices. By removing the honeycomb lattices and forming nanopores with specific geometry and size, nanoporous graphene has been demonstrated as a very high-efficiency separation membrane, due to the ultrafast molecular permeation rate for its one-atom thickness. This review focuses on the recent advances in nanoporous graphene membrane for the applications of gas separation and water purification, with a major emphasis on the molecular permeation mechanisms and the advanced fabrication methods of this state-of-the-art membrane. We highlight the advanced theoretical and experimental works and discuss the gas/water molecular transport mechanisms through the graphene nanopores accompanied with theoretical models. In addition, we summarize some representative membrane fabrication methods, covering the graphene transfer to porous substrates and the pore generation. We anticipate that this review can provide a platform for understanding the current challenges to make the conceptual membrane a reality and attracting more and more attentions from scientists and engineers.

A Novel Co(Ⅱ)-organic Framework with Multiple Active Sites for Selective Gas Adsorption

A novel metal-organic framework[Co(BTTA)(H_(2)O)_(2)]_(n)(FJI-H_(2)4)has been prepared from H_(2)BTTA ligand and CoCl_(2),and its structure was determined by single-crystal X-ray diffraction,thermogravimetric analysis,and Fourier transform infrared spectroscopy.It has relatively narrow pores and high density of open metal ions and free Lewis base sites.Gas adsorption tests demonstrate that FJI-H_(2)4 has moderate CO_(2)(34.0 cm^(3)·g^(–1))and C_(2)H_(2)(53.0 cm^(3)·g^(–1))adsorption capacity,but displays high selectivity of CO_(2)/N_(2)(87)and C_(2)H_(2)/CH_(4)(66)under ambient conditions(298 K,1 atm),which may be attributed to its relatively narrow pores and polar environment.This work will provide a potential strategy for preparing practical porous metal-organic frameworks for gas adsorption and purification.

Gas leakage monitoring with scanned-wavelength direct absorption spectroscopy

A natural gas leakage detector based on scanned-wavelength direct absorption spectroscopy is described. The sensor employs a multi-channel scanned-wavelength direct absorption strategy.It has the potential to simultaneously monitor methane and hydrogen sulfide in open path environment.Traditionally,scanned-wavelength direct absorption spectroscopy is the technique choice for natural gas leakage applications because of its simplicity,accuracy,and stability.We perform the gas sensor using direct-absorption wavelength scans with isolated features at 1-kHz repetition rate and the center wavelength is stabilized at the center of the 2v_3 band R（3） line of methane（1.65μm） and the（v_1＋v_2＋v_3） combination band of hydrogen sulfide（1.57μm）,respectively.The influence of light intensity fluctuations can be eliminated by using scanned-wavelength direct absorption spectroscopy.Because of the fast wavelength scanning,the sensor has a response time of less than 0.1 s.The sensor can be configured to sense leakages in path-integrated concentrations of,for example,100-ppm·m hydrogen sulfide and 10-ppm·m methane.

Review on cryogenic technologies for CO_(2) removal from natural gas

CO_(2) in natural gas(NG)is prone to condense directly from gas to solid or solidify from liquid to solid at low temperatures due to its high triple point and boiling temperature,which can cause a block of equipment.Meanwhile,CO_(2) will also affect the calorific value of NG.Based on the above reasons,CO_(2) must be removed during the NG liquefaction process.Compared with conventional methods,cryogenic technologies for CO_(2) removal from NG have attracted wide attention due to their nonpolluting and low-cost advantages.Its integration with NG liquefaction can make rational use of the cold energy and realize the purification of NG and the production of byproduct liquid CO_(2).In this paper,the phase behavior of the CH_(4)-CO_(2) binary mixture is summarized,which provides a basis for the process design of cryogenic CO_(2) removal from NG.Then,the detailed techniques of design and optimization for cryogenic CO_(2) removal in recent years are summarized,including the gas-liquid phase change technique and the gas-solid phase change technique.Finally,several improvements for further development of the cryogenic CO_(2) removal process are proposed.The removal process in combination with the phase change and the traditional techniques with renewable energy will be the broad prospect for future development.

High and selective capture of low-concentration CO2 with an anion-functionalized ultramicroporous metal-organic framework

CO2 capture,especially under low-pressure range,is of significance to maintain long-duration human operation in confined spaces and decrease the CO2 corrosion and freezing effect for the liquefaction of natural gas.Herein,we for the first time report a novel anion-functionalized ZU-16-Co(TIFSIX-3-Co,TIFSIX=hexafluorotitanate(TiF62−),3=pyrazine),which exhibits one-dimensional pore channels decorated by abundant F atoms,for efficient CO2 capture at a concentration around 400–10,000 ppm.Among its isostructural MFSIX-3(M=Si,Ti,Ge)family materials,ZU-16-Co with fine-tuned pore size of 3.62Åexhibits the highest CO2 uptake at 0.01 bar(10,000 ppm)and 1 bar(2.63 and 2.87 mmol g−,respectively).The high CO2 capture ability of ZU-16-Co originates from the fine-tuned pore dimensions with strong F⋯C=O host-guest interactions and relatively large pore volumes coming from its longer coordinated Ti-F-Co distance(3.9Å)in c direction.The excellent carbon trapping performance was further verified by dynamic breakthrough tests for CO2/N2(1/99 and 15/85)and CO2/CH4(50/50)mixtures.The adsorption and separation performances,resulting from the fine-tuned pore system with periodic arrays of exposed functionalities,demonstrate that ultramicroporous ZU-16-Co can be a promising adsorbent for low-concentration carbon capture.