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1.
Biomass-based combined heat and power (CHP) generation with different
carbon capture approaches is investigated in this study. Only direct carbon dioxide
(CO2) emissions are considered. The selected processes
are (i) a circulating fluidized bed boiler for wood chips connected to an
extraction/condensation steam cycle CHP plant without carbon capture; (ii) plant
(i), but with post-combustion CO2 capture; (iii) chemical
looping combustion (CLC) of solid biomass connected to the steam cycle CHP plant;
(iv) rotary kiln slow pyrolysis of biomass for biochar soil storage and direct
combustion of volatiles supplying the steam cycle CHP plant with the
CO2 from volatiles combustion escaping to the atmosphere;
(v) case (iv) with additional post-combustion CO2 capture;
and (vi) case (iv) with CLC of volatiles. Reasonable assumptions based on literature
data are taken for the performance effects of the CO2 capture
systems and the six process options are compared. CO2
compression to pipeline pressure is considered. The results show that both bioenergy
with carbon capture and storage (BECCS) and biochar qualify as negative emission
technologies (NETs) and that there is an energy-based performance advantage of BECCS
over biochar because of the unreleased fuel energy in the biochar case. Additional
aspects of biomass fuels (ash content and ash melting behavior) and sustainable soil
management (nutrient cycles) for biomass production should be quantitatively
considered in more detailed future assessments, as there may be certain biomass
fuels, and environmental and economic settings where biochar application to soils is
indicated rather than the full conversion of the biomass to energy and
CO2. 相似文献
2.
This article gives an overview of the state-of-the-art of key biomass conversion technologies currently deployed and technologies
that may play a key role in the future, including possible linkage to CO 2 capture and sequestration technology (CCS). In doing so, special attention is paid to production of biofuels for the transport
sector, because this is likely to become the key emerging market for large-scale sustainable biomass use. Although the actual
role of bio-energy will depend on its competitiveness with fossil fuels and on agricultural policies worldwide, it seems realistic
to expect that the current contribution of bio-energy of 40–55 EJ per year will increase considerably. A range from 200 to
300 EJ may be observed looking well into this century, making biomass a more important energy supply option than mineral oil
today. A key issue for bio-energy is that its use should be modernized to fit into a sustainable development path. Especially
promising are the production of electricity via advanced conversion concepts (i.e. gasification and state-of-the-art combustion
and co-firing) and modern biomass derived fuels like methanol, hydrogen and ethanol from ligno-cellulosic biomass, which can
reach competitive cost levels within 1–2 decades (partly depending on price developments with petroleum). Sugar cane based
ethanol production already provides a competitive biofuel production system in tropical regions and further improvements are
possible. Flexible energy systems, in which biomass and fossil fuels can be used in combination, could be the backbone for
a low risk, low cost and low carbon emission energy supply system for large scale supply of fuels and power and providing
a framework for the evolution of large scale biomass raw material supply systems. The gasification route offers special possibilities
to combine this with low cost CO 2 capture (and storage), resulting in concepts that are both flexible with respect to primary fuel input as well as product
mix and with the possibility of achieving zero or even negative carbon emissions. Prolonged RD&D efforts and biomass market
development, consistent policy support and international collaboration are essential to achieve this. 相似文献
3.
Chemical-looping combustion (CLC) is a combustion process with inherent separation of carbon dioxide (CO2), which is achieved by oxidizing the fuel with a solid oxygen carrier rather than with air. As fuel and combustion air are never mixed, no gas separation is necessary and, consequently, there is no direct cost or energy penalty for the separation of gases. The most common form of design of chemical-looping combustion systems uses circulating fluidized beds, which is an established and widely spread technology. Experiments were conducted in two different laboratory-scale CLC reactors with continuous fuel feeding and nominal fuel inputs of 300 Wth and 10 kWth, respectively. As an oxygen carrier material, ground steel converter slag from the Linz–Donawitz process was used. This material is the second largest flow in an integrated steel mill and it is available in huge quantities, for which there is currently limited demand. Steel converter slag consists mainly of oxides of calcium (Ca), magnesium (Mg), iron (Fe), silicon (Si), and manganese (Mn). In the 300 W unit, chemical-looping combustion experiments were conducted with model fuels syngas (50 vol% hydrogen (H2) in carbon monoxide (CO)) and methane (CH4) at varied reactor temperature, fuel input, and oxygen-carrier circulation. Further, the ability of the oxygen-carrier material to release oxygen to the gas phase was investigated. In the 10 kW unit, the fuels used for combustion tests were steam-exploded pellets and wood char. The purpose of these experiments was to study more realistic biomass fuels and to assess the lifetime of the slag when employed as oxygen carrier. In addition, chemical-looping gasification was investigated in the 10 kW unit using both steam-exploded pellets and regular wood pellets as fuels. In the 300 W unit, up to 99.9% of syngas conversion was achieved at 280 kg/MWth and 900 °C, while the highest conversion achieved with methane was 60% at 280 kg/MWth and 950 °C. The material’s ability to release oxygen to the gas phase, i.e., CLOU property, was developed during the initial hours with fuel operation and the activated material released 1–2 vol% of O2 into a flow of argon between 850 and 950 °C. The material’s initial low density decreased somewhat during CLC operation. In the 10 kW, CO2 yields of 75–82% were achieved with all three fuels tested in CLC conditions, while carbon leakage was very low in most cases, i.e., below 1%. With wood char as fuel, at a fuel input of 1.8 kWth, a CO2 yield of 92% could be achieved. The carbon fraction of C2-species was usually below 2.5% and no C3-species were detected. During chemical-looping gasification investigation a raw gas was produced that contained mostly H2. The oxygen carrier lifetime was estimated to be about 110–170 h. However, due to its high availability and potentially low cost, this type of slag could be suitable for large-scale operation. The study also includes a discussion on the potential advantages of this technology over other technologies available for Bio-Energy Carbon Capture and Storage, BECCS. Furthermore, the paper calls for the use of adequate policy instruments to foster the development of this kind of technologies, with great potential for cost reduction but presently without commercial application because of lack of incentives. 相似文献
4.
Syngas is a clean energy carrier and a major industrial feedstock. In this paper, syngas was produced via biomass chemical looping gasification(CLG) process. Hematite, the most common Fe-based oxygen carrier(OC), was modified with different metal oxides(CeO 2, CaO and MgO) by the impregnation method. The hematite modified by CeO 2, CaO and MgO was namely as CeO 2-hematite(CeO 2-H), CaO-hematite(CaO-H) and MgO-hematite(MgO-H), respectively. The introduction... 相似文献
5.
This study evaluated the release characteristics of mercury from bituminous coal in chemical looping combustion (CLC) using Australian iron ore as the oxygen carrier in a fixed bed reactor. The effects of several parameters, such as temperature in the fuel reactor (FR) and air reactor (AR), gasification medium in the FR, and reaction atmosphere in the AR, on mercury release characteristics, were investigated. The mercury speciation and release amount in the FR and AR under different conditions were further explored. The results indicate that most of the mercury in coal was released in the FR, while the rest of it was released in the AR. Hg 0 was found to be the major species in the released mercury. The results also indicate that a higher temperature in the FR led to an increase in the total mercury release amount and a decrease in Hg 0 proportion. However, a higher temperature in the AR resulted in a decrease in the total mercury release amount and Hg 0 proportion. The increase in the H 2O/CO 2 ratio of gasification mediums in the FR was beneficial for the increase in the total mercury release amount and Hg 0 proportion. A higher O 2 concentration in reaction atmosphere in AR had a negligible effect on the total mercury release amount, but a positive effect on Hg 0 oxidization. 相似文献
6.
Corporate image, European Emission Trading System and Environmental
Regulations, encourage pulp industry to reduce carbon dioxide
(CO2) emissions. Kraft pulp mills produce
CO2 mainly in combustion processes. The largest sources
are the recovery boiler, the biomass boiler, and the lime kiln. Due to utilizing
mostly biomass-based fuels, the CO2 is largely biogenic.
Capture and storage of CO2 (CCS) could offer pulp and paper
industry the possibility to act as site for negative CO2
emissions. In addition, captured biogenic CO2 can be used as
a raw material for bioproducts. Possibilities for CO2
utilization include tall oil manufacturing, lignin extraction, and production of
precipitated calcium carbonate (PCC), depending on local conditions and
mill-specific details. In this study, total biomass-based CO2
capture and storage potential (BECCS) and potential to implement capture and
utilization of biomass-based CO2 (BECCU) in kraft pulp mills
were estimated by analyzing the impacts of the processes on the operation of two
modern reference mills, a Nordic softwood kraft pulp mill with integrated paper
production and a Southern eucalyptus kraft pulp mill. CO2
capture is energy-intensive, and thus the effects on the energy balances of the
mills were estimated. When papermaking is integrated in the mill operations, energy
adequacy can be a limiting factor for carbon capture implementation. Global carbon
capture potential was estimated based on pulp production data. Kraft pulp mills have
notable CO2 capture potential, while the on-site utilization
potential using currently available technologies is lower. The future of these
processes depends on technology development, desire to reuse
CO2, and prospective changes in legislation. 相似文献
7.
生物质半焦作为生物质气化的副产物,其固定碳含量和热值均高于原生物质.若将生物质半焦充分利用将大幅提高生物质利用的能量效率,具有很大的经济和环境效益.在综合热分析基础上,考察了生物质半焦添加比例(掺烧比)对生物质微米燃料旋风炉燃烧炉膛温度、烟气及灰分的影响.试验研究发现掺烧比为20%(空气当量比为1.2,粉体粒径在0.177 mm以下,生物质含水率控制在8.1%以下),燃烧效果最好,燃烧效率高达98%,燃烧烟气中有害气体NOx和SO2的含量较少. 相似文献
8.
在化学链燃烧(CLC)过程中,载氧体表面的原子结构和电子特性决定了其化学反应活性.本文以Fe_2O_3为载氧体,探讨了其自然条件下主要裸露的高米勒数指表面(1-1 2)的结构性质,研究发现表面不同配位数的氧和铁原子(包括O2f、O3f、O4f、Fe4f和Fe5f)的键参数、电子态密度及电荷布居等存在明显差异.为探究这种差异对Fe_2O_3反应活性的影响,对比分析了CO在表面5种氧和铁原子位生成CO_2的吸附-反应机理.CO在表面低配位O原子O2f和O3f首先形成物理吸附,然后被晶格氧氧化生成CO_2,反应需要克服能垒分别为3.657 e V和3.401 e V;然而,CO在O4f位吸附时,首先克服1.864 e V能垒形成二齿形碳酸盐物种,之后克服1.097 e V的能垒形成CO_2.当CO在Fe4f和Fe5f位吸附时,CO与Fe原子成键,后经过活化与表面O原子成键,形成二齿形碳酸盐物种,能垒分别为0.416和0.219 e V,最终碳酸盐物种分别克服0.500和1.462e V的能垒生成CO_2.因此,可以推断表面高配位数的O4f、Fe4f和Fe5f原子,由于其较高的氧化态,在化学链燃烧过程中充当活性位的作用.本研究有助于了解铁基载氧体表面化学链燃烧反应的微观机理,并为载氧体表面结构性能调控制备提供理论借鉴. 相似文献
9.
The combination of concentrated solar power–chemical looping air separation (CSP-CLAS) with an oxy-fuel combustion process for carbon dioxide (CO2) capture is a novel system to generate electricity from solar power and biomass while being able to store solar power efficiently. In this study, the computer program Advanced System for Process Engineering Plus (ASPEN Plus) was used to develop models to assess the process performance of such a process with manganese (Mn)-based oxygen carriers on alumina (Al2O3) support for a location in the region of Seville in Spain, using real solar beam irradiance and electricity demand data. It was shown that the utilisation of olive tree prunings (Olea europaea) as the fuel—an agricultural residue produced locally—results in negative CO2 emissions (a net removal of CO2 from the atmosphere). Furthermore, it was found that the process with an annual average electricity output of 18 MW would utilise 2.43% of Andalusia’s olive tree prunings, thereby capturing 260.5 k-tonnes of CO2, annually. Drawbacks of the system are its relatively high complexity, a significant energy penalty in the CLAS process associated with the steam requirements for the loop-seal fluidisation, and the gas storage requirements. Nevertheless, the utilisation of agricultural residues is highly promising, and given the large quantities produced globally (~?4 billion tonnes/year), it is suggested that other novel processes tailored to these fuels should be investigated, under consideration of a future price on CO2 emissions, integration potential with a likely electricity grid system, and based on the local conditions and real data. 相似文献
10.
This paper investigates overall CO 2 balances of combined heat and power (CHP) plants with CO 2 capture and storage (CCS) in Kraft pulp and paper mills. The CHP plants use biomass-based fuels and feature advanced gasification and combined cycle technology. Results from simple process simulations of the considered CHP plants are presented. Based on those results and taking into account the major direct and indirect changes in CO 2 emissions, the study shows that implementing CCS leads to steep emission reductions. Furthermore, a preliminary cost assessment is carried out to analyse the CO 2 mitigation cost and its dependence on the distance that the CO 2 must be transported to injection sites. 相似文献
11.
The Clean Development Mechanism (CDM) of the Kyoto Protocol provides Annex-I (industrialized) countries with an incentive to invest in emission reduction projects in non-Annex-I (developing) countries to achieve a reduction in CO 2 emissions at lowest cost that also promotes sustainable development in the host country. Biomass gasification projects could be of interest under the CDM because they directly displace greenhouse gas emissions while contributing to sustainable rural development. However, there is only one biomass gasifier project registered under the CDM so far. In this study, an attempt has been made to assess the economic potential of biomass gasifier-based projects under CDM in India. The preliminary estimates based on this study indicate that there is a vast theoretical potential of CO 2 mitigation by the use of biomass gasification projects in India.The results indicate that in India around 74 million tonne agricultural residues as a biomass feedstock can be used for energy applications on an annual basis. In terms of the plant capacity the potential of biomass gasification projects could reach 31 GW that can generate more than 67 TWh electricity annually. The annual CER potential of biomass gasification projects in India could theoretically reach 58 million tonnes. Under more realistic assumptions about diffusion of biomass gasification projects based on past experiences with the government-run programmes, annual CER volumes by 2012 could reach 0.4–1.0 million and 1.0–3.0 million by 2020. The projections based on the past diffusion trend indicate that in India, even with highly favorable assumptions, the dissemination of biomass gasification projects is not likely to reach its maximum estimated potential in another 50 years. CDM could help to achieve the maximum utilization potential more rapidly as compared to the current diffusion trend if supportive policies are introduced. 相似文献
12.
Due to its large reserves, coal is expected to continue to play an important role in the future. However, specific and absolute
CO 2 emissions are among the highest when burning coal for power generation. Therefore, the capture of CO 2 from power plants may contribute significantly in reducing global CO 2 emissions. This review deals with the oxyfuel process, where pure oxygen is used for burning coal, resulting in a flue gas
with high CO 2 concentrations. After further conditioning, the highly concentrated CO 2 is compressed and transported in the liquid state to, for example, geological storages. The enormous oxygen demand is generated
in an air-separation unit by a cryogenic process, which is the only available state-of-the-art technology. The generation
of oxygen and the purification and liquefaction of the CO 2-enriched flue gas consumes significant auxiliary power. Therefore, the overall net efficiency is expected to be lowered by
8 to 12 percentage points, corresponding to a 21 to 36% increase in fuel consumption. Oxygen combustion is associated with
higher temperatures compared with conventional air combustion. Both the fuel properties as well as limitations of steam and
metal temperatures of the various heat exchanger sections of the steam generator require a moderation of the temperatures
during combustion and in the subsequent heat-transfer sections. This is done by means of flue gas recirculation. The interdependencies
among fuel properties, the amount and the temperature of the recycled flue gas, and the resulting oxygen concentration in
the combustion atmosphere are investigated. Expected effects of the modified flue gas composition in comparison with the air-fired
case are studied theoretically and experimentally. The different atmosphere resulting from oxygen-fired combustion gives rise
to various questions related to firing, in particular, with regard to the combustion mechanism, pollutant reduction, the risk
of corrosion, and the properties of the fly ash or the deposits that form. In particular, detailed nitrogen and sulphur chemistry
was investigated by combustion tests in a laboratory-scale facility. Oxidant staging, in order to reduce NO formation, turned
out to work with similar effectiveness as for conventional air combustion. With regard to sulphur, a considerable increase
in the SO 2 concentration was found, as expected. However, the H 2S concentration in the combustion atmosphere increased as well. Further results were achieved with a pilot-scale test facility,
where acid dew points were measured and deposition probes were exposed to the combustion environment. Besides CO 2 and water vapour, the flue gas contains impurities like sulphur species, nitrogen oxides, argon, nitrogen, and oxygen. The
CO 2 liquefaction is strongly affected by these impurities in terms of the auxiliary power requirement and the CO 2 capture rate. Furthermore, the impurity of the liquefied CO 2 is affected as well. Since the requirements on the liquid CO 2 with regard to geological storage or enhanced oil recovery are currently undefined, the effects of possible flue gas treatment
and the design of the liquefaction plant are studied over a wide range. 相似文献
13.
This paper deals with field related experience of a low temperature industrial heat application through biomass gasification.
The gasification system is essentially consists of an open top down draft reactor lined with ceramic. The experiment reveals
that 6.5 kg of liquefy petroleum gas (LPG) is fully replaced by 38 kg of sized wood on hourly basis. The maximum temperature
attained was 367°C in 130 min at 100.7 Nm 3 h −1 gas flow rate. This system has resulted a saving of about 19.5 tons of LPG over 3,000 h of operation, implying a saving of
about 33 tons of CO 2 emission, thus a promising candidate for clean development mechanism. Fuel economic analysis of gasifier system showed that
the saving was about 13,850 US$ for 3,000 h of baking operation. 相似文献
14.
Atmospheric pollution and global warming issues are increasingly becoming major environmental concerns. Fire is one of the significant sources of pollutant gases released into the atmosphere; and tropical biomass fires, which are of particular interest in this study, contribute greatly to the global budget of CO and CO 2. This pioneer research simulates the natural biomass burning strategy in Malaysia using an experimental burning facility. The investigation was conducted on the emissions (CO 2, CO, and Benzene, Toluene, Ethylbenzene, Xylenes (BTEX)) from ten tropical biomass species. The selected species represent the major tropical forests that are frequently subjected to dry forest fire incidents. An experimental burning facility equipped with an on-line gas analyzer was employed to determine the burning emissions. The major emission factors were found to vary among the species, and the specific results were as follows. The moisture content of a particular biomass greatly influenced its emission pattern. The smoke analysis results revealed the existence of BTEX, which were sampled from a combustion chamber by enrichment traps aided with a universal gas sampler. The BTEX were determined by organic solvent extraction followed by GC/MS quantification, the results of which suggested that the biomass burning emission factor contributed significant amounts of benzene, toluene, and m,p-xylene. The modified combustion efficiency (MCE) changed in response to changes in the sample moisture content. Therefore, this study concluded that the emission of some pollutants mainly depends on the burning phase and sample moisture content of the biomass. 相似文献
15.
Fossil fuel combustion and many industrial processes generate gaseous emissions that contain a number of toxic organic pollutants and carbon dioxide (CO 2) which contribute to climate change and atmospheric pollution. There is a need for green and sustainable solutions to remove air pollutants, as opposed to conventional techniques which can be expensive, consume additional energy and generate further waste. We developed a novel integrated bioreactor combined with recyclable iron oxide nano/micro-particle adsorption interfaces, to remove CO 2, and undesired organic air pollutants using natural particles, while generating oxygen. This semi-continuous bench-scale photo-bioreactor was shown to successfully clean up simulated emission streams of up to 45% CO 2 with a conversion rate of approximately 4% CO 2 per hour, generating a steady supply of oxygen (6 mmol/hr), while nanoparticles effectively remove several undesired organic by-products. We also showed algal waste of the bioreactor can be used for mercury remediation. We estimated the potential CO 2 emissions that could be captured from our new method for three industrial cases in which, coal, oil and natural gas were used. With a 30% carbon capture system, the reduction of CO 2 was estimated to decrease by about 420,000, 320,000 and 240,000 metric tonnes, respectively for a typical 500 MW power plant. The cost analysis we conducted showed potential to scale-up, and the entire system is recyclable and sustainable. We further discuss the implications of usage of this complete system, or as individual units, that could provide a hybrid option to existing industrial setups. 相似文献
16.
CO 2-normalized emission ratios (ΔX/ΔCO 2; V/V; where ΔX and ΔCO 2 = the enhancement of trace gas and CO 2, respectively, above background levels) for carbon monoxide (CO), hydrogen (H 2), methane (CH 4), total nonmethane hydrocarbons (TNMHC), and nitrous oxide (N 2O) were determined from smoke samples collected during low-altitude helicopter flights over two prescribed fires in northern Ontario, Canada. The emission ratios determined from these prescribed boreal forest fires are compared to emission ratios determined over two graminoid (grass) wetlands fires in central Florida and are found to be substantially higher (elevated levels of reduced gas production relative to CO 2) during all stages of combustion. These results argue strongly for the need to characterize biomass burning emissions from the major global vegetation/ecosystems in order to couple combustion emissions to their vegetation/ecosystem type. Such a process should improve the quality of any assessments of biomass burning impacts on atmospheric chemistry and climate. 相似文献
17.
Chemical looping combustion (CLC) of coal has gained increasing attention as a novel combustion technology for its advantages in CO2 capture. Sulfur evolution from coal causes great harm from either the CLC operational or environmental perspective. In this research, a combined MnFe2O4 oxygen carrier (OC) was synthesized and its reaction with a typical Chinese high sulfur coal, Liuzhi (LZ) bituminous coal, was performed in a thermogravimetric analyzer (TGA)-Fourier transform infrared (FT-IR) spectrometer. Evolution of sulfur species during reaction of LZ coal with MnFeaO40C was systematically investigated through experimental means combined with thermodynamic simulation. TGA-FTIR analysis of the LZ reaction with MnFe2O4 indicated MnFe2O4 exhibited the desired superior reactivity compared to the single reference oxides Mn304 or Fe203, and SO2 produced was mainly related to oxidization of H2S by MnFe2O4. Experimental analysis of the LZ coal reaction with MnFe2O4, including X-ray diffraction and X-ray photoelectron spectroscopy analysis, verified that the main reduced counterparts of MnFe2O4 were Fe304 and MnO, in good agreement with the related thermodynamic simulation. The obtained MnO was beneficial to stabilize the reduced MnFe2O4 and avoid serious sintering, although the oxygen in MnO was not fully utilized. Meanwhile, most sulfur present in LZ coal was converted to solid MnS during LZ reaction with MnFe2O4, which was further oxidized to MnSO4. Finally, the formation of both MnS and such manganese silicates as Mn2SiO4 and MnSiO3 should be addressed to ensure the full regeneration of the reduced MnFe2O4. 相似文献
18.
Binary oxide systems (CuCr 2O 4, CuCo 2O 4), deposited onto cordierite monoliths of honeycomb structure with a second support (finely dispersed Al 2O 3), were prepared as filters for catalytic combustion of diesel soot using internal combustion engine's gas exhausts (O 2, NO x, H 2O, CO 2) and O 3 as oxidizing agents. It is shown that the second support increases soot capacity of aforementioned filters, and causes dispersion of the particles of spinel phases as active components enhancing thereby catalyst activity and selectivity of soot combustion to CO 2. Oxidants used can be arranged with reference to decreasing their activity in a following series: O 3 >> NO 2 > H 2O > NO > O 2 > CO 2. Ozone proved to be the most efficient oxidizing agent: the diesel soot combustion by O 3 occurs intensively (in the presence of copper chromite based catalyst) even at closing to ambient temperatures. Results obtained give a basis for the conclusion that using a catalytic coating on soot filters in the form of aforementioned binary oxide systems and ozone as the initiator of the oxidation processes is a promising approach in solving the problem of comprehensive purification of automotive exhaust gases at relatively low temperatures, known as the "cold start" problem. 相似文献
19.
The power sector in Thailand is the largest contributor to CO 2 emissions. There is high potential to mitigate CO 2 emission via alternative power generating plants. Alternative plants considered in this study include nuclear plants, integrated gasification combined cycle plants, biomass-based plants and supercritical thermal power plants. The biomass-based plants considered here are fueled with four types of biomass; paddy husk, municipal solid waste (MSW), fuel wood and corncob. The methodology for the optimal expansion plan of the power generating system over the planning horizon is based on the least-cost approach. The results from the least-cost planning analyses show that the nuclear alternative has the highest potential to mitigate not only CO 2 but also other airborne emissions. Moreover, the nuclear option is the most effective abatement strategy for CO 2 reduction due to its negative incremental cost of CO 2 reduction. 相似文献
20.
Sorbents for CO_2 capture have been prepared by wet impregnation of a commercial active carbon(Ketjen-black, Akzo Nobel) with two CO_2-philic compounds, polyethylenimine(PEI)and tetraethylenepentamine(TEPA), respectively. The effects of amine amount(from 10 to70 wt.%), CO_2 concentration in the feed, sorption temperature and gas hourly space velocity on the CO_2 capture performance have been investigated. The sorption capacity has been evaluated using the breakthrough method, with a fixed bed reactor equipped with on line gas chromatograph. The samples have been characterized by N_2 adsorption–desorption,scanning electron microscopy and energy dispersive X-ray(SEM/EDX). A promising CO_2 sorption capacity of 6.90 mmol/gsorbenthas been obtained with 70 wt.% of supported TEPA at 70℃ under a stream containing 80 vol% of CO_2. Sorption tests, carried out with simulated biogas compositions(CH_4/CO_2mixtures), have revealed an appreciable CO_2 separation selectivity; stable performance was maintained for 20 adsorption–desorption cycles. 相似文献
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