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This report was written to satisfy a milestone of the Enhanced Coal Bed Methane Recovery and CO2 Sequestration task of the Big Sky Carbon Sequestration project. The report begins to assess the costs associated with separating the CO2 from flue gas and then injecting it into an unminable coal seam. The technical challenges and costs associated with...
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... process flow for a typical amine absorption process is fairly simple (see Figure 2). The operations of the main unit consist of an absorber tower, a stripper column, and a heat exchanger to recover heat from the hot regenerated solvent. ...
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... pressures in other CO 2 pipelines are 1500 to 1800 psia [22]. Figure 25 shown below, shows the pressure distribution of the pipeline. This plot was created using the Pipesoft software after a successful simulation of the pipeline. ...
Citations
... Фиг.1. Направления с индустриална перспектива, в които се развиват технологиите за намаляване на емисиите от CO 2 Важен аспект в решаването на технологичното предизвикателство е техникоикономическо обезпечаване на процесите по сепарация на СО 2 [5]. За целите на действащата индустрия с дълъг ресурс на работа, основните параметри, които обуславят избора на инсталация за улавяне на въглероден диоксид са: ниски инвестиционни и експлоатационни разходи; надеждност и гъвкавост на технологията; безопасност и екологична съвместимост при работа на съоръженията и съхранението на реагенти и реакционни продукти. ...
2 върху повърхността на зеолит, синтезиран от летяща пепел. Проведени са експерименти с газова смес от CO 2 и N 2 в обемно съотношение 10/90, с дебит 30 ml/min при 25 ° С. Опитната установка се състои от адсорбционна колона, запълнена със зеолит от пепел и газов хро-матограф за детекция на концентрациите. Изследвана е десорбцията при 50, 60 и 120 о С. Установеният капацитет на динамична адсорбция е в диапазона 100-115 mgCO 2 /g, като е постигнато 87 % възстановяване на адсорбента при температура на десорбция от 50 о С. Получените резултати показват висок потенциал за приложимост на изследвания материал в системи за улавяне на въглеродни емисии чрез физична адсорбция. Ключови думи: адсорбция, десорбция, въглероден диоксид, летяща пепел, зео-лит DYNAMIC STUDY OF CARBON DIOXIDE ADSORPTION/DESORPTION ONTO FLY ASH ZEOLITES Denitza Zgureva Abstract: In this study the process of dynamic adsorption and desorption of CO 2 onto fly ash zeolite surface was investigated. The experiments were performed with CO 2 /N 2 gas mixture in a volume ratio of 10/90, flow rate of 30 ml/min at 25 o C. The experimental set up is equipped with a dynamic adsorption column with fly ash zeolite bed and a gas chromatograph for concentration detection. Desorption process was studied at three temperatures: 50, 60, and 120 o C. The adsorption capacity of fly ash zeo-lite is obtained in the range of 100-150 mgCO 2 /g, as the 87 % recovery was achieved by desorption at low temperature of 50 o C. These results reveal high potential of the investigated materials for application in carbon capture systems by physical adsorp-tion.
... The reactor mobility enables synthesis of methanol at sites that have 'free' carbon dioxide streams. Such streams include high purity CO 2 (99%) from ethanol fermentation facilities [82] or medium purity CO 2 (12%) from power plants [24,83]. Wastewater treatment facilities also emit CO 2 at various concentrations, depending on the size and treatment type [84]. ...
A methanol synthesis unit (MSU) that directly converts carbon dioxide and hydrogen into methanol and water was developed and tested. The MSU consists of: a high-pressure side that includes a compressor, a reactor, and a throttling valve; and a low-pressure side that includes a knockout drum, and a mixer where fresh gas enters the system. Methanol and water are produced at high pressure in the reactor and then exit the system under low pressure and temperature in the knockout drum. The remaining, unreacted recycle gas that leaves the knockout drum is mixed with fresh synthesis gas before being sent back through the synthesis loop. The unit operates entirely on electricity and includes a high-pressure electrolyzer to obtain gaseous hydrogen and oxygen directly from purified water. Thus, the sole inputs to the trailer are water, carbon dioxide, and electricity, while the sole outputs are methanol, oxygen, and water. A distillation unit separates the methanol and water mixture on site so that the synthesized water can be reused in the electrolyzer. Here, we describe and characterize the operation of the MSU and offer some possible design improvements for future iterations of the device, based on experience.
... Kolejna z metod separacji gazów -metoda membranowa -wykorzystuje selektywność przenikania określonych składników przez materiał membrany, a zatem nie wymaga stosowania procesu regeneracji, nie jest też metodą energochłonną, podobnie jak adsorpcja [6,7]. Zaletą metody membranowej jest możliwość modułowej budowy systemu. ...
... Zaletą metody membranowej jest możliwość modułowej budowy systemu. Problemem jest możliwość zanieczyszczenia powierzchni membrany [6] oraz niewystarczająca selektywność, która wymaga stosowania wieloetapowego procesu połączonego z recyrkulacją strumienia [7]. W przypadku stosowania metody kriogenicznej separacja gazu polega na kondensacji CO 2 w niskiej temperaturze i przy odpowiednio wysokim ciśnieniu. ...
... Adding inhibitors or preventative coating to the inside surface of the pipeline via pigging can reduce this corrosion. If this corrosion is not caught as soon as possible, the lifespan of the pipeline will be greatly reduced and it will have a negative impact on the overall economics (Robertson, 2007). ...
... Wyoming has several large point source carbon dioxide emitters with total emissions of about 57 Mt CO 2 per year (Robertson, 2007). Table 2 lists the coal-fired power plants in the state, which account for over 80% of Wyoming's total point source emissions with the balance coming from trona processing, petroleum refining, and cement manufacture. ...
... Nitrogen and carbon dioxide respectively account for 67.0 mol% and 11.8 mol% of the flue gas discharged from the Wyodak PC power plant (Table 3). On average, 9344 Mg CO 2 are emitted each day from the Wyodak facility (Robertson, 2007). The Wyodak-Anderson subbituminous coal zone is the largest coal zone in the Powder River Basin. ...
... The tariff calculation applies to both injection scenarios. Robertson (2007) reported that a CO 2 pipeline transporting gas separated from the Wyodak power plant would cost about $522,000/km with a throughput of 2,383,000 m 3 /D. Using these costs, the tariff for the CO 2 injection scenario was calculated to be $0.000201/m 3 /km. ...
Unminable coal beds are potentially large storage reservoirs for the sequestration of anthropogenic CO2 and offer the benefit of enhanced methane production, which can offset some of the costs associated with CO2 sequestration. The objective of this report is to provide a final topical report on enhanced coal bed methane recovery and CO2 sequestration to the U.S. Department of Energy in fulfillment of a Big Sky Carbon Sequestration Partnership milestone. This report summarizes work done at Idaho National Laboratory in support of Phase II of the Big Sky Carbon Sequestration Partnership. Research that elucidates the interaction of CO2 and coal is discussed with work centering on the Powder River Basin of Wyoming and Montana. Sorption-induced strain, also referred to as coal swelling/shrinkage, was investigated. A new method of obtaining sorption-induced strain was developed that greatly decreases the time necessary for data collection and increases the reliability of the strain data. As coal permeability is a strong function of sorption-induced strain, common permeability models were used to fit measured permeability data, but were found inadequate. A new permeability model was developed that can be directly applied to coal permeability data obtained under laboratory stress conditions, which are different than field stress conditions. The coal permeability model can be used to obtain critical coal parameters that can be applied in field models. An economic feasibility study of CO2 sequestration in unminable coal seams in the Powder River Basin of Wyoming was done. Economic analyses of CO2 injection options are compared. Results show that injecting flue gas to recover methane from CBM fields is marginally economical; however, this method will not significantly contribute to the need to sequester large quantities of CO2. Separating CO2 from flue gas and injecting it into the unminable coal zones of the Powder River Basin seam is currently uneconomical, but can effectively sequester over 86,000 tons (78,200 Mg) of CO2 per acre while recovering methane to offset costs. The cost to separate CO2 from flue gas was identified as the major cost driver associated with CO2 sequestration in unminable coal seams. Improvements in separations technology alone are unlikely to drive costs low enough for CO2 sequestration in unminable coal seams in the Powder River Basin to become economically viable. Breakthroughs in separations technology could aid the economics, but in the Powder River Basin, they cannot achieve the necessary cost reductions for breakeven economics without incentives.
In the effort to create a sustainable future economy, the ability to directly convert dilute gas-phase CO2 in waste gas streams into useful products would be a valuable tool, which may be achievable using Grignard reagents as both the capture and the conversion materials. The magnesium salt by-product can be recovered, and metallic magnesium regenerated through conventional high-efficiency electrolysis. This stoichiometric approach is known as Metal Looping, where the magnesium acts as the energy vector for the capture and conversion, allowing both to occur at room temperature and atmospheric pressure. However, the process has only previously been demonstrated with 12% CO2 in nitrogen mixtures. If we consider this process in a real post-combustion flue gas conversion scenario, the sensitivity of Grignard reagents to other gases (and water vapour) must be considered. While some of these gases and the water vapour are relatively easily removed, in most flue gas streams the most common other gas present, oxygen, would be far more challenging to excise, and oxygen is known to react with Grignard reagents, albeit slowly. In order to determine if higher oxygen concentrations could be tolerated, allowing the possibility of a variety of relatively inexpensive and possibly profitable direct CO2 conversion pathways to be developed, a range of industrially relevant CO2/O2 mixtures were made and carefully bubbled through phenylmagnesium bromide solutions.
Substitution of fossil gaseous fuels with biomass-based gases is of interest to the iron and steel industry due to its role in the mitigation of anthropogenic CO2 emissions. In switching from fossil fuels to biomass-based gases, a systems analysis of the full value chain from biomass supply to the production and supply of final gas products becomes crucial. This study uses process and heat integration methods in combination with a supply chain evaluation to analyse full value chains of biomass-based gases for fossil gas replacement within the iron and steel industry. The study is carried out as a specific case study in order to understand the implications of utilizing bio-syngas/bio-SNG as heating fuels in iron- and steel-making, and to provide insights into the most sensitive parameters involved in fuel switching. The results show a significant cost difference in the fuel production of the two gas products owing to higher capital and biomass use in the bio-SNG value chain option. When tested for sensitivity, biomass price, transportation distance, and capital costs show the most impact on fuel production costs across all options studied. Trade-offs associated with process integration, plant localisation, feedstock availability and supply were found to varying extents.
Gas absorption using aqueous amines is a technology that is oft en considered in the recovery of carbon dioxide (CO2) from post-combustion gases in electric power plants. Certain amines have a high affinity for CO2 at low partial pressures and the basic process has been proven through decades of use in the natural gas and hydrocarbon processing industries. Nevertheless, the use of the amine process in flue gas treating is met with considerable challenges. The chemistry of the CO2-amine reaction favors contacting conditions at high pressure and low temperature, opposite of those found in flue gas treating. Combustion gases, including sulfur dioxide and oxygen, and particulate matter require special handling to reduce reagent degradation and foaming. Low contacting pressure produces large volumetric rates of flue gas and results in extreme equipment sizes. The basic amine process has been modified to adapt to these challenges. Specialty amines and solvent formulation aim to reach a compromise between solution reactivity and capacity. Novel mechanical design of contacting equipment and process configuration can be used to overcome limitations of pressure drop and heat effects. In this work, fundamentals of gas absorption with chemical reaction are revisited to identify areas of the amine process that limit its effectiveness in flue gas-treating operations. A discussion of chemical reaction kinetics, contacting conditions, and absorber design is presented with examples to illustrate the impact on CO2 recovery.
This paper reports studies on CO2 capture technologies and presents the mathematical modeling, simulation, and optimization of adsorption-based process alternatives, namely, pressure swing adsorption (PSA) and vacuum swing adsorption (VSA). Each technology includes feed dehydration, capture of at least 90% of CO2 from the feed, and compression to almost pure CO2 for sequestration at 150 bar. Each process alternative is optimized over a range of feed CO2 compositions and flow rates. A superstructure of alternatives is developed to select the optimum dehydration strategy for feed to each process. A four-step process with pressurization, adsorption in multiple columns packed with 13X zeolite, N2 purging, and product recovery at moderate to low vacuum is configured. A nonlinear algebraic and partial differential equation (NAPDE) based nonisothermal adsorption model is used, which is fully discretized and solved via a kriging model. Explicit expressions for costs as functions of feed flow rate and CO2 composition are also developed for the PSA- and VSA-based CO2 capture and compression for the first time. Furthermore, a cost-based comparison of four leading CO2 capture technologies, namely, absorption-, membrane-, PSA-, and VSA-based processes, is presented over a range of flue gas compositions and flow rates. This enables selection of the most cost-effective CO2 capture and storage (CCS) technology for diverse emission scenarios. Results indicate that CO2 can be captured with the least cost using a MEA-based chemical absorption when the feed CO2 composition is less than 15–20%. For higher CO2 compositions, VSA is the preferred process.
Studies on leading technologies for industrial CO2 capture are performed. Each technology includes flue gas dehydration, capture of at least 90% of CO2 from the feed, and compression to almost pure CO2 for sequestration at 150 bar. This paper presents the modeling, simulation, optimization, and energy integration of a monoethanolamine (MEA)-based chemical absorption process and a multistage membrane process over a range of feed compositions (1–70% CO2, 5.5–15% H2O, 5.5% O2, and the balance N2) and flow rates (0.1, 1, 5, and 10 kmol/s). A superstructure of process alternatives is developed to select the optimum dehydration strategy for the feed to each process. A rigorous simulation-based optimization model is proposed to determine the minimum annualized cost of the MEA-absorption process. The MEA-absorption process is energy integrated through heat exchanger network optimization. A novel mathematical model is developed for the optimization of multistage and multicomponent separation of CO2 using membranes, which can be also used for a range of membrane-based gas separation applications. The results showing the optimum investment, operating, and total costs provide a quantitative approach toward technology comparison and scaling up the absorption- and membrane-based CO2 capture from various CO2 emitting industries. Explicit expressions for the investment and operating costs of each alternative postcombustion CO2 capture process as functions of feed flow rate and CO2 composition are also developed for the first time. This may assist the decision-makers in selecting the cost-appropriate technology for comprehensive carbon management by taking the diverse emission scenarios into consideration.
