Elsevier

Applied Energy

Volume 170, 15 May 2016, Pages 269-277
Applied Energy

Engineering, environmental and economic performance evaluation of high-gravity carbonation process for carbon capture and utilization

https://doi.org/10.1016/j.apenergy.2016.02.103Get rights and content

Highlights

  • Energy consumption and CO2 reduction potential were evaluated based on field test.

  • Environmental impacts in terms of mid- and end-points were quantified using ReCiPe.

  • Revenue including profits and costs was estimated at different electricity prices.

  • HiGCarb can reduce up to 6.5% CO2 emissions within the steel and cement industries.

  • Best operation modulus of HiGCarb was identified using 15 KPI by 3E triangle model.

Abstract

Multi-waste treatment of slag and wastewater can be combined with CO2 capture in the steelmaking industry by the high-gravity carbonation (i.e., HiGCarb) process using a rotating packed bed. In this study, the HiGCarb process is comprehensively evaluated by an engineering, environmental and economic (3E) triangle model. The feedstock CO2 for the HiGCarb process can be obtained directly from the industrial stacks, eliminating the need for additional CO2 concentration and transportation. The reacted steelmaking slag, i.e., basic oxygen furnace slag (BOFS), is suited as cement substitution material, avoiding environmental burden from the cement industry, also a CO2-intensive emission source. Significant environmental benefits can be realized by establishing the waste-to-resource supply chain between the steelmaking and cement industries. The life-cycle assessment shows a net CO2 capture amount by the HiGCarb process of 282 kg-CO2/t-BOFS, accompanied by a CO2 avoidance of 997 kg-CO2/t-BOFS due to the product utilization. Moreover, the amount of revenue gained was estimated to be 20.2–23.2 USD/t-BOFS treated by the HiGCarb process. According to the 3E triangle model, the HiGCarb process is shown to be environmentally promising and economically feasible due to its high overall engineering performance, which makes it suitable as a potential CO2 sink in industry.

Graphical abstract

A 3E triangle model was used to evaluate tradeoffs in CO2 capture performance by the developed HiGCarb process while considering the larger life-cycle environmental impacts due to energy use and material consumption as well as the economic implications of the revenue gained and the operating costs.

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Introduction

Accelerated mineralization, so-called accelerated carbonation, refers to the reaction of CO2 with alkaline divalent cations from natural ores [1] or alkaline solid wastes, such as steel slag [2] and fly ash [3], to produce carbonate minerals. The process chemistry of accelerated mineralization, in the presence of water, can be briefly expressed as Eq. (1):MO(s)+H2O(l)+CO2(g)MCO3(s)+H2O(l)where M is a divalent cation (e.g., Ca2+ or Mg2+), and MCO3 is a carbonate product (e.g., CaCO3 or MgCO3). Since the carbonate product is stable at atmospheric conditions, accelerated mineralization has been considered as one of the permanent CO2 sequestration technologies in a scalable manner, especially when alkaline solid wastes are used as the feedstock of the mineralization process [4], [5], [6]. Kirchofer et al. [7], [8] estimated a direct mitigation potential of 1.8–23.7% of the total CO2 emissions in the U.S., depending on the availability of alkalinity sources and the performance of the mineral carbonation. In addition, indirect CO2 emissions from the cement industry can be avoided since the reacted product (e.g., carbonated solid wastes) can be used as supplementary cementitious materials in cement and concrete [7], [9]. Compared to the total global CO2 emissions, although the CO2 sequestration potential by accelerated mineralization using the solid wastes is low, it offers unique application for hazardous waste remediation and provides a means for industries to produce valuable by-products from the waste while reducing the CO2 emissions [10].

For mineralization using solid wastes, extensive efforts have been underway to evaluate the effect of various key operating factors on carbonation conversion and to characterize the carbonate product for potential utilization [11], [12], [13]. The carbonation performance, i.e., rates of metal ion leaching and CO2 dissolution, can also be promoted by introducing wastewater from the steelmaking industries [14], [15], [16]. Since accelerated mineralization has been shown to be a diffusion-controlled reaction [9], [17], [18], [19], the mass transfer rate of the CO2 dissolution and metal ion diffusion has increased using enhanced leaching [20], autoclave [21], rotating packed bed (RPB) [14], [15], [22], and ultrasound [23], [24].

Among the aforementioned methods, accelerated mineralization using the RPB, also referred to as the high-gravity carbonation (HiGCarb) process, is an attractive approach. The HiGCarb process achieves a high CO2 capture efficiency (i.e., >98%) with a relatively short reaction time at ambient temperature and pressure [22]. Using the centrifugal force provided by the RPB reactor, the mass transfer rate of carbonation in the HiGCarb process was significantly greater than that using a fix packed bed. The height of a transfer unit in a liquid-film limited system (i.e., carbonation) can be reduced to 4–66 cm using the HiGCarb process [25]. In addition, the environmental impacts of the HiGCarb process were lower compared to using conventional processes, such as autoclave reactor [26].

The life-cycle assessment (LCA) approach has been used as the most suitable tool for environmental assessment of CO2 utilization technologies and processes along their entire life cycles [27], [28], [29], [30]. Several studies on the LCA of mineral carbonation using different processes have been published [26], [31], [32], [33], [34]. These studies employed inventory data from lab-scale experiments in contrast to our work which is based on a real industry installation. For this reason, stages of the life-cycle such as raw material production and end-product utilization were not included in the literature. Furthermore, several critical issues for the HiGCarb process such as energy consumption, net CO2 emission reduction, indirect CO2 emission avoidance, and cost-benefit analysis of the HiGCarb process have not been comprehensively addressed yet.

For these reasons, in this study, the HiGCarb process is systematically assessed from the perspectives of engineering, environment and economy (referred to as 3E in this paper) using a triangle model. Since the complex relationships among 3E aspects can be easily visualized on a ternary plot among different scenarios, the triangle graphical presentation can be used for evaluating key factors that are related but also complementary [35], [36]. The energy consumption, net CO2 capture amount, and environmental impacts by the HiGCarb process were evaluated by means of LCA. In addition, the revenue gained of HiGCarb was estimated by considering operating cost and process profits (such as carbon credits and product sales). Furthermore, according to the results of the comprehensive performance evaluation through the 3E triangle model, operating guidelines for the HiGCarb process were proposed.

Section snippets

Scopes and definitions of business-as-usual and HiGCarb process

To critically evaluate the benefits of integrating the HiGCarb process in the steelmaking industry, the performance before (i.e., business-as-usual case) and after integration of HiGCarb process was evaluated. Table S1 (see Appendix A) presents a comparison of business-as-usual and integration of the HiGCarb process in the steelmaking industry from the 3E aspects. In the business-as-usual case, the alkaline cold-rolling mill wastewater is neutralized and adjusted by chemical agents at a

Analysis of energy uses for HiGCarb process

Fig. 3 shows the energy consumption of the main unit processes in the nine HiGCarb scenarios. It should be noted that the results, herein, are referred to a different functional unit, i.e., per t-CO2, since energy consumption is one of the major concerns to the cost effectiveness of a CO2 capture process. The total energy consumption of the HiGCarb process was estimated to range from 205 to 440 kW h/t-CO2, with a capture scale of 75–170 kg CO2 per day. The pre-processing of material, i.e., BOFS

Conclusions

To develop and implement the waste-to-resource supply chain between the steelmaking and cement industries, a comprehensive performance evaluation on the high-gravity carbonation (HiGCarb) process was carried out by the 3E triangle model, i.e., from the engineering, environmental and economic point of view. The capture capacity of the HiGCarb process was 75–170 kg CO2 per day, associated with an energy consumption ranging from 205 to 440 kW h/t-CO2. Compared to the business-as usual case, the

Acknowledgements

High appreciation goes to the Green Talents Program granted by BMBF through the Project Management Agency c/o German Aerospace Center (PT-DLR) in Germany. The authors also acknowledge the support of Ministry of Science and Technology (MOST) of Taiwan (R.O.C.) under Grant Number MOST 105-3113-E-007-001. In addition, Prof. André Bardow from Institute of Technical Thermodynamics at RWTH Aachen University, Germany, is greatly appreciated for his suggestions to this work.

References (61)

  • E.E. Chang et al.

    CO2 sequestration by carbonation of steelmaking slags in an autoclave reactor

    J Hazard Mater

    (2011)
  • R.M. Santos et al.

    Synthesis of pure aragonite by sonochemical mineral carbonation

    Chem Eng Res Des

    (2012)
  • R.M. Santos et al.

    Ultrasound-intensified mineral carbonation

    Appl Therm Eng

    (2013)
  • S.-Y. Pan et al.

    Systematic approach to determination of optimum gas-phase mass transfer rate for high-gravity carbonation process of steelmaking slags in a rotating packed bed

    Appl Energy

    (2015)
  • H.H. Khoo et al.

    Carbon capture and utilization: preliminary life cycle CO2, energy, and cost results of potential mineral carbonation

    Energy Procedia

    (2011)
  • R. Zevenhoven et al.

    Carbon storage by mineralisation (CSM): serpentinite rock carbonation via Mg(OH)2 reaction intermediate without CO2 pre-separation

    Energy Procedia

    (2013)
  • F. Bodénan et al.

    Ex situ mineral carbonation for CO2 mitigation: evaluation of mining waste resources, aqueous carbonation processability and life cycle assessment (Carmex project)

    Miner Eng

    (2014)
  • Q. Yi et al.

    3E (energy, environmental, and economy) evaluation and assessment to an innovative dual-gas polygeneration system

    Energy

    (2014)
  • J.D. Silvestre et al.

    From the new European Standards to an environmental, energy and economic assessment of building assemblies from cradle-to-cradle (3E–C2C)

    Energy Build

    (2013)
  • F.-L. Xu et al.

    A triangle model for evaluating the sustainability status and trends of economic development

    Ecol Model

    (2006)
  • T. Zhang et al.

    Preparation of high performance blended cements and reclamation of iron concentrate from basic oxygen furnace steel slag

    Resour Conserv Recycl

    (2011)
  • J.J.M. Galo et al.

    Criteria for smart grid deployment in Brazil by applying the Delphi method

    Energy

    (2014)
  • Y.M. Al-Saleh et al.

    Carbon capture, utilisation and storage scenarios for the Gulf Cooperation Council region: a Delphi-based foresight study

    Futures

    (2012)
  • S. Kodama et al.

    Development of a new pH-swing CO2 mineralization process with a recyclable reaction solution

    Energy

    (2008)
  • E.E. Chang et al.

    Carbonation of basic oxygen furnace slag with metalworking wastewater in a slurry reactor

    Int J Greenhouse Gas Control

    (2013)
  • E.E. Chang et al.

    Accelerated carbonation of steelmaking slags in a high-gravity rotating packed bed

    J Hazard Mater

    (2012)
  • A. Hasanbeigi et al.

    Emerging energy-efficiency and CO2 emission-reduction technologies for cement and concrete production: a technical review

    Renew Sustain Energy Rev

    (2012)
  • C. Tan et al.

    Absorption of carbon dioxide with piperazine and its mixtures in a rotating packed bed

    Sep Purif Technol

    (2006)
  • C.-H. Yu et al.

    Effects of inorganic salts on absorption of CO2 and O2 for absorbents containing diethylenetriamine and piperazine

    Int J Greenhouse Gas Control

    (2014)
  • A. Sanna et al.

    A review of mineral carbonation technologies to sequester CO2

    Chem Soc Rev

    (2014)
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