Transformation and migration of cadmium during chemical-looping combustion/gasification of municipal solid waste

Chen, Peng; Sun, Xiaoqing; Gao, Mingming; Ma, Jingjing; Guo, Qingjie

doi:10.1016/j.cej.2019.02.041

Cited by 37 publications

(16 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The residual form of Ni is 50.01%, which is a much lower risk to the environment when compared to other heavy metals. The difference of heavy metal chemical distribution is mainly related to its physicochemical characteristics (volatility, melting point, boiling point); it is hardly related to the total content of heavy metal, and these results are also consistent with other research studies [27].…”

Section: Characteristics Of Heavy Metals In Mswi Fly Ashsupporting

confidence: 90%

Heavy Metals Removing from Municipal Solid Waste Incineration Fly Ashes by Electric Field-Enhanced Washing

et al. 2020

View full text Add to dashboard Cite

Municipal solid waste incineration (MSWI) fly ash contains chlorides, heavy metals, and organic pollutants, which requires appropriate disposal to eliminate this risk. In this study, the effects of agents on heavy metals removal from MSWI fly ash by electric field-enhanced washing were systematically studied. The results show that when these fly ashes were washed at a current density of 35 mA/cm 2 , polarity switching frequency of 40 Hz, Ethylenediaminetetraacetic acid (EDTA) dosage of 0.5 mol/L, and a pH of 2 for 4 h, almost all of the Cd and Ni could be were removed, with a removal efficiency of 100.00% and 99.59%, respectively. Meanwhile, it also shows a significant effect on Cu and Zn, with a removal efficiency higher than 85%. After washing, the results of the sequential extraction procedure showed that the residual forms of Pb, Cu, Zn, Cd, Ni, and As increased obviously. According to GB5085.3-2007, the toxicity of the treated MSWI fly ash were below their thresholds of 5 and 1 mg/L for Pb and Cd, respectively. Thus, a novel technology for heavy metals removal from MSWI fly ash is proposed.

show abstract

Section: Characteristics Of Heavy Metals In Mswi Fly Ashsupporting

confidence: 90%

Heavy Metals Removing from Municipal Solid Waste Incineration Fly Ashes by Electric Field-Enhanced Washing

et al. 2020

View full text Add to dashboard Cite

show abstract

“…Chemical looping (CL) is a near-zero emission coal-based technology in which multiple interacting loops of flowing, reactive, gas/solid mixtures produce energy via solid-oxygen carrier based combustion [2][3][4]. Chemical looping has remained an area of active research focused on improving its economic viability and reducing environmental footprint [5,6]. To reduce waste stream volumes and required energy, advanced optimizing control systems for the chemical looping process are required.…”

Section: Introductionmentioning

confidence: 99%

Multiresolution GPC-Structured Control of a Single-Loop Cold-Flow Chemical Looping Testbed

et al. 2020

View full text Add to dashboard Cite

Chemical looping is a near-zero emission process for generating power from coal. It is based on a multi-phase gas-solid flow and has extremely challenging nonlinear, multi-scale dynamics with jumps, producing large dynamic model uncertainty, which renders traditional robust control techniques, such as linear parameter varying H ∞ design, largely inapplicable. This process complexity is addressed in the present work through the temporal and the spatiotemporal multiresolution modeling along with the corresponding model-based control laws. Namely, the nonlinear autoregressive with exogenous input model structure, nonlinear in the wavelet basis, but linear in parameters, is used to identify the dominant temporal chemical looping process dynamics. The control inputs and the wavelet model parameters are calculated by optimizing a quadratic cost function using a gradient descent method. The respective identification and tracking error convergence of the proposed self-tuning identification and control schemes, the latter using the unconstrained generalized predictive control structure, is separately ascertained through the Lyapunov stability theorem. The rate constraint on the control signal in the temporal control law is then imposed and the control topology is augmented by an additional control loop with self-tuning deadbeat controller which uses the spatiotemporal wavelet riser dynamics representation. The novelty of this work is three-fold: (1) developing the self-tuning controller design methodology that consists in embedding the real-time tunable temporal highly nonlinear, but linearly parametrizable, multiresolution system representations into the classical rate-constrained generalized predictive quadratic optimal control structure, (2) augmenting the temporal multiresolution loop by a more complex spatiotemporal multiresolution self-tuning deadbeat control loop, and (3) demonstrating the effectiveness of the proposed methodology in producing fast recursive real-time algorithms for controlling highly uncertain nonlinear multiscale processes. The latter is shown through the data from the implemented temporal and augmented spatiotemporal solutions of a difficult chemical looping cold flow tracking control problem.

show abstract

“…Chen et al 31 used the CLC process to check the adsorption property of copper- and iron-based OCs on cadmium present in MSW. In this experiment, synthetic MSW, which contains different waste samples with a large amount of cadmium, was used in a fixed bed reactor.…”

Section: Introductionmentioning

confidence: 99%

Process Modelling of Chemical Looping Combustion of Paper, Plastics, Paper/Plastic Blend Waste, and Coal

Yaqub

Oboirien

2020

ACS Omega

View full text Add to dashboard Cite

Chemical looping combustion (CLC) is a novel carbon capture and storage technology that can be used in the proper disposal of municipal solid waste when used as a solid fuel. In this study, the results of the CLC of paper, plastics, and paper/plastic blends were compared with CLC of South African coal using Chemcad software. The simulation was done for two different CLC processes, namely, chemical looping oxygen uncoupling (CLOU) and in situ gasification CLC (IG-CLC). The results demonstrated that coal at 66% had a lower CO 2 yield than paper (86%) but a higher yield than all the plastic samples in CLOU (3356%) and an equal CO 2 yield in paper and all plastic samples in IG-CLC. Furthermore, coal had a lower CO 2 gas yield than all the optimum blends (72–85%) for CLOU and an equal yield with the entire paper/plastic blend in IG-CLC. On combustion efficiency, coal has a lower combustion efficiency at 80% than paper and polyvinyl chloride (PVC) at 90 and 96%, respectively, but a higher efficiency than other plastic samples that are between 30 and 70% in CLOU while in IG-CLC, it had a lower efficiency than paper, PVC, and polyethylene terephthalate and higher efficiency than high-density polyethylene, low-density polyethylene, polypropylene, and polystyrene. For paper/plastic blends, coal has higher combustion efficiency than all the paper/plastic blends in both CLOU and IG-CLC processes except for the paper/PVC where the combustion efficiency was higher than coal.

show abstract

Transformation and migration of cadmium during chemical-looping combustion/gasification of municipal solid waste

Cited by 37 publications

References 38 publications

Heavy Metals Removing from Municipal Solid Waste Incineration Fly Ashes by Electric Field-Enhanced Washing

Heavy Metals Removing from Municipal Solid Waste Incineration Fly Ashes by Electric Field-Enhanced Washing

Multiresolution GPC-Structured Control of a Single-Loop Cold-Flow Chemical Looping Testbed

Process Modelling of Chemical Looping Combustion of Paper, Plastics, Paper/Plastic Blend Waste, and Coal

Contact Info

Product

Resources

About