We present eco-technoeconomic analyses of four processes, including two novel designs, for the purification of captured CO2 from flue gas for a petroleum coke (petcoke) oxy-combustion power plant operated with carbon capture and sequestration (CCS). A base case petcoke oxy-combustion design obtained from a previous study consisting of flue gas water removal using condensation was used in this study. Other purification processes evaluated consist of a cryogenic distillation petcoke oxy-combustion with CCS, an oxygen deficient petcoke oxy-combustion with CCS and a catalytic dehydration petcoke oxy-combustion via hydrogen conversion with CCS. An eco-technoeconomic analysis considering greenhouse gas (GHG) emissions, levelized cost of electricity (LCOE), thermal efficiency and CO2 product purity to meet pipe-line specifications, was conducted on all purification candidates. This revealed that base case design did not meet the CO2 pipeline specifications. The highest LCOE was attributed to... [more]

This submission contains Aspen Plus files for the design and systems performance analysis of oxy-combustion power plant captured CO2 purification using different techniques.

The effects of a hydrogen bond acceptor and hydrogen bond donor on carbon dioxide absorption via natural deep eutectic solvents were studied in this work. Naturally occurring non-toxic deep eutectic solvent constituents were considered; choline chloride, b-alanine, and betaine were selected as hydrogen bond acceptors; lactic acid, malic acid, and fructose were selected as hydrogen bond donors. Experimental gas absorption data were collected via experimental methods that uses gravimetric principles. Carbon dioxide capture data for an isolated hydrogen bond donor and hydrogen bond acceptor, as well as natural deep eutectic solvents, were collected. In addition to experimental data, a theoretical study using Density Functional Theory was carried out to analyze the properties of these fluids from the nanoscopic viewpoint and their relationship with the macroscopic behavior of the system, and its ability for carbon dioxide absorption. The combined experimental and theoretical reported appro... [more]

To reduce the anthropogenic CO2 emissions produced from fossil fuel burning plants, the application of carbon capture and storage (CCS) is necessary and development of a more efficient and economically feasible CO2 capture process is essential as an alternative to the conventional amine scrubbing process which uses aqueous amine solutions. CO2 capture can be enhanced by improving both the gas−solid contact efficiency and by tuning a specific high-performance sorbent. The aim of this research is to investigate the adsorption of CO2 using impregnated mesoporous silica in a “confined-fluidized bed”. This non-conventional fluidized bed (sometimes also termed the “packed-fluidized bed”) seems suitable for improving the efficiency of gas−solid processes for which the bypass effect of the gas−solid contact caused by bubbling represents a major drawback. Results, expressed as grams of CO2 adsorbed per kilogram of material, are discussed in terms of amine load in the sorbent, breakthrough time... [more]

Experimental and simulation studies for carbon dioxide (CO2) adsorption on porous silica glass were performed to reveal how surface heterogeneity can affect the adsorption mechanism of CO2. In performing the simulation, the structure of porous silica glass was modeled as a slit pore consisting of parallel walls of connected SiO4 units. The adsorption isotherms of CO2 at 283 K were generated for a series of pore widths using a Monte Carlo ensemble. The defective surfaces created by random removal of surface atoms and the surfaces containing hydroxyl functional groups were chosen to represent the surface heterogeneity for the simulation tasks. The isotherms derived for the defective surfaces showed a rapid adsorption at low pressures because of the stronger interaction between the rough nonuniform surfaces and CO2 molecules. For the role of surface functional groups, the adsorption isotherms dramatically increased with an increasing number of functional groups. The amount of CO2 adsorbed... [more]

Carbon capture and utilization (CCU) may offer a response to climate change mitigation from major industrial emitters. CCU can turn waste CO2 emissions into valuable products such as chemicals and fuels. Consequently, attention has been paid to petrochemical industries as one of the best options for CCU. The largest industrial CO2 removal monoethanol amine-based plant in Iran has been simulated with the aid of a chemical process simulator, i.e., Aspen HYSYS® v.10. The thermodynamic properties are calculated with the acid gas property package models, which are available in Aspen HYSYS®. The results of simulation are validated by the actual data provided by Kermanshah Petrochemical Industries Co. Results show that there is a good agreement between simulated results and real performance of the plant under different operational conditions. The main parameters such as capture efficiency in percent, the heat consumption in MJ/kg CO2 removed, and the working capacity of the plant are calculat... [more]

This is an Aspen Plus v12 model for a Rectisol process used for removing CO2 from a shifted syngas stream arising from steam methane reforming for the purposes of Blue hydrogen production. It is intended for educational use, and is useful as a starting point for those interested in simulating this process. It is not optimized in any way, but it contains a working flowsheet for those interested in modifying it for your own purposes.

The simulation was developed using the simulation strategy given in Adams TA II, Khojestah Salkuyeh Y, Nease J. Processes and Simulations for Solvent-based CO2Capture and Syngas Cleanup. Chapter in: Reactor and process design for in sustainable energy technology. Elsevier (2014). Pages 163-232. ISBN: 978-0-444-59566-9. It is based on the process discussed in Doctor RD, Molburg JC, Thimmapuram PR, Berry GF, Livengood CD. Gasification combined cycle: carbon dioxide recovery, transport, and disposal. US DOE Report, Argonne National Laboratory ANL/ESD-24. 19... [more]

The accompanying model for the paper 'Optimal design and operation of a waste tire feedstock polygeneration system' is presented. The model is written using the GOSSIP software platform and modeling language.

The [hmim][Tf2N] ionic liquid is considered in this work to develop a model in Aspen Plus® capturing carbon dioxide from shifted flue gas through physical absorption. Ionic liquids are innovative and promising green solvents for the capture of carbon dioxide. As an important aspect of this research, optimization is carried out for the carbon capture system through a central composite design: simulation and statistical analysis are combined together. This leads to important results such as the identification of significant factors and their combinations. Surface plots and mathematical models are developed for capital costs, operating costs and removal of carbon dioxide. These models can be used to find optimal operating conditions maximizing the amount of captured carbon dioxide and minimizing total costs: the percentage of carbon dioxide removal is 93.7%, operating costs are 0.66 million €/tonCO2 captured (due to the high costs of ionic liquid), and capital costs are 52.2 €/tonCO2 capt... [more]

Carbon dioxide (CO2), a major greenhouse gas, capture has recently become a crucial technological solution to reduce atmospheric emissions from fossil fuel burning. Thereafter, many efforts have been put forwarded to reduce the burden on climate change by capturing and separating CO2, especially from larger power plants and from the air through the utilization of different technologies (e.g., membrane, absorption, microbial, cryogenic, chemical looping, and so on). Those technologies have often suffered from high operating costs and huge energy consumption. On the right side, physical process, such as adsorption, is a cost-effective process, which has been widely used to adsorb different contaminants, including CO2. Henceforth, this review covered the overall efficacies of CO2 adsorption from air at 196 K to 343 K and different pressures by the carbon-based materials (CBMs). Subsequently, we also addressed the associated challenges and future opportunities for CBMs. According to this r... [more]

Growing concern on global warming directly related to CO2 emissions is steering the implementation of carbon capture and storage (CCS). With Malaysia having an estimated 37 Tscfd (Trillion standard cubic feet) of natural gas remains undeveloped in CO2 containing natural gas fields, there is a need to assess the viability of CCS implementation. This study performs a techno-economic analysis for CCS at an offshore natural gas field in Malaysia. The framework includes a gas field model, revenue model, and cost model. A techno-economic spreadsheet consisting of Net Present Value (NPV), Payback Period (PBP), and Internal Rate of Return (IRR) is developed over the gas field’s production life of 15 years for four distinctive CO2 capture technologies, which are membrane, chemical absorption, physical absorption, and cryogenics. Results predict that physical absorption solvent (Selexol) as CO2 capture technology is most feasible with IRR of 15% and PBP of 7.94 years. The output from the techno-... [more]

In this study, a well-to-wheels life cycle assessment was conducted to determine the environmental impacts from disposing of petroleum coke by converting it into liquid fuel. Specifically, three processes for converting petroleum coke and natural gas to Fischer Tropsch diesel were investigated, both with and without carbon capture and sequestration (CCS). Impact categories were calculated using the EPA’s TRACI 2.1 US-Canada 2008 midpoint method in SimaPro software. In addition, the impact of grid emissions on the overall process was assessed using two representative Canadian locations with high (Alberta) and low (Ontario) grid emissions. The results of each impact category were compared among the designs and against conventional petroleum and oil-sands derived diesel. Key findings showed that the proposed designs when operated using CCS in the low-emissions-grid location had lower life cycle GHG emissions than conventional petroleum and oil-sands derived diesel. Nevertheless, the vario... [more]

In this study, the kinetics of flue gas hydrate formation in bulk water in the presence of selected amino acids and surfactants are investigated. Four amino acids (3000 ppm) are selected based on different hydropathy index. Constant-ramping and isothermal experiments at 120 bar pressure and 1 °C temperature are carried out to compare their hydrate promotion capabilities with surfactant sodium dodecyl sulfate (SDS) (500−3000 ppm) and water. Based on experimental results, we report the correlation between hydrate promotion capability of amino acids and their hydrophobicity. Hydrophobic amino acids show stronger flue gas hydrate promotion capability than water and hydrophilic amino acids. We discuss the controlling mechanisms to differentiate between promoters and inhibitors’ roles among the amino acids. Between 2000−3000 ppm concentrations, hydrophobic amino acids have near similar promotion capabilities as SDS. This research highlights the potential use of amino acids as promoters or in... [more]

Post combustion CO2 capture is still a rather energy intense, and therefore expensive, process. Much of the current research for reducing the process energy requirements is focused on the regeneration section. A good description of the vapor liquid equilibrium of the solvent is necessary for the accurate representation of the process. 3-(Diethylamino)-1,2-propanediol (DEA-12-PD) and 1-(2-hydroxyethyl)piperidine (12-HEPP) have been proposed as potential components in solvent blends for the membrane contactor. However, there are few available experimental data for these two tertiary amines making difficult to accurate simulate such process. In this work, we provide experimental data on the pure component saturation pressure (383 to 443 K) and on VLE of aqueous solutions of these amines (313 to 373 K) in order to fill part of the data gap. The data were used to estimate model parameters used to represent the data. The saturation pressure was modeled using the Antoine equation and the devi... [more]

A mathematical model of a continuous moving-bed temperature-swing adsorption (MBTSA) process for post-combustion CO₂ capture in a coal-fired power plant context has been developed. Process simulations have been done using single component isotherms and measured gas diffusion parameters of an activated carbon adsorbent. While a simple process configuration with no gas re-circulation gives quite low capture rate and CO₂ purity, 86% and 65%, respectively, more advanced process configurations where some of the captured gas is recirculated to the incoming flue gas drastically increase both the capture rate and CO₂ purity, the best configuration reaching capture rate of 86% and CO₂ purity of 98%. Further improvements can be achieved by using adsorbents with higher CO₂/N₂ selectivity and/or higher temperature of the regeneration section.

The behavior of Fe₂O₃/Al₂O₃ particles as oxygen carriers (OCs) for CO chemical looping combustion (CLC) under different reaction temperatures (700 °C, 800 °C, 900 °C, and 1000 °C) were tested in a lab-scale fluidized bed and a thermogravimetric analysis (TGA) unit. The results show that the oxygen carrier presents the highest reactivity at 800 °C, even after 30 cycles of redox reaction in a fluidized bed, while more obvious carbon deposition occurred for the case at 700 °C, and agglomeration for the case at 1000 °C. Moreover, the detailed behavior of the prepared Fe₂O₃/Al₂O₃ particle was detected in the TGA apparatus at different reaction temperatures. Furthermore, temperature-programming TGA experiments were performed to investigate the influence of different CO concentrations and CO/CO₂ concentrations on the reaction between CO and OC during the chemical looping combustion processes. Based on these experimental behaviors of the prepared Fe₂O₃/Al₂O₃ during the CLC of CO, the detailed... [more]

Iron ore was studied as a CO2 absorbent. Carbonation was carried out by mechanochemical and high temperature−high pressure (HTHP) reactions. Kinetics of the carbonation reactions was studied for the two methods. In the mechanochemical process, it was analyzed as a function of the CO2 pressure and the rotation speed of the planetary ball mill, while in the HTHP process, the kinetics was studied as a function of pressure and temperature. The highest CO2 capture capacities achieved were 3.7341 mmol of CO2/g of sorbent in ball milling (30 bar of CO2 pressure, 400 rpm, 20 h) and 5.4392 mmol of CO2/g of absorbent in HTHP (50 bar of CO2 pressure, 100 °C and 4 h). To overcome the kinetics limitations, water was introduced to all carbonation experiments. The calcination reactions were studied in Argon atmosphere using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analysis. Siderite can be decomposed at the same temperature range (100 °C to 420 °C) for the samples... [more]

Thermochemical conversion of solid wastes through gasification offers the dual benefit of production of high-value fuels and
environmentally friendly waste disposal. Waste tires in particular may be a suitable feedstock for gasification as a result of their
high energy content (LHV of approximately 34 MJ/kg, higher than coal), high volatile matter content, and low ash content. Rotary
kilns for steam gasification are a promising and technologically mature option to handle such difficult solid wastes that have a
wider range of compositions, particle sizes, and moisture contents. In this paper, we propose a novel process for production of
liquefied synthetic natural gas (SNG) from waste tires. We use experimental data available in the open literature to represent the
complex steam gasification unit operation and study three design cases: Without CCS, with precombustion CCS and with preand postcombustion CCS in two locations: USA and Norway. The thermodynamic, economic and environmen... [more]

Low-cost activated carbons were prepared from waste polyurethane foam by physical activation with CO2 for the first time and chemical activation with Ca(OH)2, NaOH, or KOH. The activation conditions were optimized to produce microporous carbons with high CO2 adsorption capacity and CO2/N2 selectivity. The sample prepared by physical activation showed CO2/N2 selectivity of up to 24, much higher than that of chemical activation. This is mainly due to the narrower microporosity and the rich N content produced during the physical activation process. However, physical activation samples showed inferior textural properties compared to chemical activation samples and led to a lower CO2 uptake of 3.37 mmol·g−1 at 273 K. Porous carbons obtained by chemical activation showed a high CO2 uptake of 5.85 mmol·g−1 at 273 K, comparable to the optimum activated carbon materials prepared from other wastes. This is mainly attributed to large volumes of ultra-micropores (<1 nm) up to 0.212 cm3·g−1 and... [more]

The potential of carbon capture and storage to provide a low carbon fossil-fueled power generation sector that complements the continuously growing renewable sector is becoming ever more apparent. An optimization of a post combustion capture unit employing the solvent monoethanolamine (MEA) was carried out using a Taguchi design of experiment to mitigate the parasitic energy demands of the system. An equilibrium-based approach was employed in Aspen Plus to simulate 90% capture of the CO2 emitted from a 600 MW natural gas combined-cycle gas turbine power plant. The effects of varying the inlet flue gas temperature, absorber column operating pressure, amount of exhaust gas recycle, and amine concentration were evaluated using signal to noise ratios and analysis of variance. The optimum levels that minimized the specific energy requirements were a: flue gas temperature = 50 °C; absorber pressure = 1 bar; exhaust gas recirculation = 20% and; amine concentration = 35 wt%, with a relative im... [more]

The petroleum coke gasification integrated gasification combined cycle power plant (petcoke-IGCC) is a promising avenue for disposal of the ever-growing amount of stockpiled petroleum coke. In this work, we present a novel techno-economic and life cycle assessment of the process operated with carbon capture and sequestration. The proposed petcoke-to-electricity plant is designed and simulated in Aspen Plus v10. The proposed power plant was compared against coal integrated gasification combined cycle (coal-IGCC) and supercritical pulverized coal power plants operated with carbon capture and sequestration. The results showed that although the efficiency of the coal-IGCC plant is higher than the petcoke-IGCC plant, the higher energy density of the petcoke and lower resource costs were such that the levelized cost of electricity of petcoke-IGCC was lower than coal-IGCC. Furthermore, the feed flow rate of petcoke to the petcoke-IGCC process is approximately 15% lower than the coal feed rate... [more]

The application of circulating fluidized bed technology in calcium looping (CaL) requires that CaO-based sorbents should be manufactured in the form of spherical pellets. However, the pelletization of powdered sorbents is always hampered by the problem that the mechanical strength of sorbents is improved at the cost of loss in CO₂ sorption performance. To promote both the CO₂ sorption and anti-attrition performance, in this work, four kinds of pore-forming materials were screened and utilized to prepare sorbent pellets via the extrusion-spheronization process. In addition, impacts of the additional content of pore-forming material and their particle sizes were also investigated comprehensively. It was found that the addition of 5 wt.% polyethylene possesses the highest CO₂ capture capacity (0.155 g-CO₂/g-sorbent in the 25th cycle) and mechanical performance of 4.0 N after high-temperature calcination, which were about 14% higher and 25% improved, compared to pure calcium hydrate pellet... [more]

One of the largest engineering challenges of our time is finding technical solutions that permit the use of our energy resources in a sustainable way. In order to achieve meaningful and positive change, new energy systems must adhere to the triple bottom line of sustainability. This means that new technical solutions must be economically, socio-politically, and environmentally sustainable, such that they can be rapidly adopted and accepted. The engineering literature is full of a great many technical proposals for new energy systems, but it turns out to be quite hard to objectively look at them all, see through the hype, and decide which are the best and most promising technologies in which to invest our research and development dollars. In this talk, I will present a case study with the results of our recent meta-study covering over 100 candidate electricity generation systems with carbon dioxide capture, in order to determine which are the most promising classes of technologies. I wi... [more]

The rapid development of modern society has resulted in an increased demand for energy, mainly from fossil fuels. The use of this source of energy has led to the accumulation of carbon dioxide (CO₂) in the atmosphere. In this context, microalgae culturing may be an effective solution to reduce the CO₂ concentration in the atmosphere, since these microorganisms can capture CO₂ and, simultaneously, produce bioenergy. This work consists of a techno-economic assessment of a microalgal production facility integrated in a petrochemical complex, in which established infrastructure allows efficient material and energy transport. Seven different scenarios were considered regarding photosynthetic, lipids extraction and anaerobic digestion efficiencies. This analysis has demonstrated six economically viable scenarios able to: (i) reduce CO₂ emissions from a thermoelectric power plant; (ii) treat domestic wastewaters (which were used as culture medium); and (iii) produce lipids and electrical and... [more]

In this study, a novel biomass-gas-and-nuclear-to-liquids (BGNTL) process is proposed. In this process, nuclear heat is used as the heat source of a steam methane reforming (SMR) process. In a prior work, a rigorous model was developed for the integrated nuclear heat and steam methane reforming process in the gPROMS software package. This model was applied to simulate the integrated nuclear heat and SMR section of BGNTL in Aspen Plus within the other process sections. The BGNTL process was considered for producing different fuels including gasoline & diesel or dimethyl ether (DME). Carbon capture and sequestration (CCS) is considered as an optional section. The performance of the BGNTL process was compared against a non-nuclear process called biomass-and-gas-to-liquids (BGTL). The efficiency, economics, and environmental impact analyses show that the BGNTL process to produce DME is the most efficient, economic and environmentally friendly process among the considered designs. As a resu... [more]