@article{narode_hao_pourghaz_ducoste_barlaz_2024, title={Measurement and Temperature Prediction from Ash Disposed in Landfills Using a Quasi-Adiabatic Flow Reactor}, volume={5}, ISSN={["2690-0645"]}, url={https://doi.org/10.1021/acsestengg.4c00023}, DOI={10.1021/acsestengg.4c00023}, abstractNote={Models that describe heat accumulation in landfills show that ash hydration and carbonation can be a significant source of heat. Ash contains CaO and Ca(OH)2 as well as other oxides and hydroxides that undergo hydration and carbonation reactions. However, there is no data on heat evolution from ash under landfill conditions to parametrize heat accumulation models. The objective of this study was to develop and demonstrate a quasi-adiabatic reactor to measure heat generation from ash under landfill conditions. The reactor method was validated with CaO and Ca(OH)2 and then demonstrated for 6 coal ash and 6 municipal solid waste (MSW) ash samples. Heat recovery in the reactors was ∼104.5% and 106% of theoretical for CaO hydration and Ca(OH)2 carbonation, respectively. The heat generation potential of the ashes varied from 11 to 583 and 78 to 297 J g–1 for coal and MSW, respectively. The wide range demonstrated the uniqueness of each ash. Using the measured rate and extent of heat generation, model simulations showed an insignificant effect on landfill temperatures at 10% ash for most samples, while at 20% ash, two of the coal ashes resulted in predicted temperature increases of 51 and 71 °C relative to the burial of MSW only.}, journal={ACS ES&T ENGINEERING}, author={Narode, Asmita and Hao, Zisu and Pourghaz, Moe and Ducoste, Joel J. and Barlaz, Morton A.}, year={2024}, month={May} } @article{hao_barlaz_ducoste_2023, title={Quasi-Mechanistic 3D Finite Element Model Predicts Temperatures in a U.S. Landfill}, volume={11}, ISSN={["2690-0645"]}, url={https://doi.org/10.1021/acsestengg.3c00289}, DOI={10.1021/acsestengg.3c00289}, abstractNote={There have been reports of North American municipal solid waste landfills exhibiting temperatures in excess of 80 °C. Although mathematical models have been developed to predict heat generation and accumulation in landfills, predictions have not been compared to temperature data from a full-scale landfill that receives heat generating ash. The objectives of this study were to apply a three-dimensional finite element model to a southeastern U.S. landfill and to compare model predictions with field data. The model incorporates gas–liquid–heat reactive transfer with exothermic biological reactions and hydration and carbonation of ash. An 8-step reconstruction approach digitalized the landfill geometry for the incorporation of a site-specific waste disposal strategy and initial and boundary conditions. The model was calibrated to adjust laboratory-measured rates of ash hydration and carbonation to the field rates. Once calibrated, the results showed a total root-mean-square error of 11 °C across 40 measurements in five temperature probes. The model predicted an elevated temperature zone in a region of the landfill between two temperature probes, and the predicted temperatures were consistent with the temperature trends in gas collection wells. The model is sensitive to the CaO content of ash, highlighting the importance of understanding the ash composition prior to disposal.}, journal={ACS ES&T ENGINEERING}, author={Hao, Zisu and Barlaz, Morton A. and Ducoste, Joel J.}, year={2023}, month={Nov} } @article{hao_ho_2019, title={Supported Liquid Membranes in Pharmaceutics and Biotechnology}, ISBN={["978-0-12-813606-5"]}, DOI={10.1016/B978-0-12-813606-5.00009-9}, abstractNote={Pharmaceutics and biotechnology play a vital role for both human beings and the environment. In pharmaceutics and biotechnology, separation processes, using supported liquid membranes (SLMs) in particular, are extensively applied for the removal and recovery of active ingredients from diluted aqueous solutions produced by fermentation and/or enzymatic synthesis. This chapter reviews the significant advances and widespread activities of SLMs in pharmaceutics and biotechnology, especially for the selective removal and recovery of antibiotics such as Cephalexin, Cephalosporin C, Penicillin G, and Amoxicillin. Important parameters that impact the mass transfer performance of SLMs are discussed and highlighted. Future perspectives on the development of SLMs are also highlighted.}, journal={CURRENT TRENDS AND FUTURE DEVELOPMENTS ON (BIO-) MEMBRANES: MEMBRANE PROCESSES IN THE PHARMACEUTICAL AND BIOTECHNOLOGICAL FIELD}, author={Hao, Zisu and Ho, W. S. Winston}, year={2019}, pages={259–289} } @inproceedings{hao_sun_ducoste_barlaz_2017, title={A Model to Describe Heat Generation and Accumulation at Municipal Solid Waste Landfills}, ISBN={9780784480434}, url={http://dx.doi.org/10.1061/9780784480434.030}, DOI={10.1061/9780784480434.030}, abstractNote={There have been reports of landfills in North America that are experiencing elevated temperatures that are resulting in challenging issues for landfill management. The objective of this study is to develop a box model to describe the generation, consumption and release of heat in landfills and subsequently to predict temperature profiles. Initially, a box model was developed that treats the landfill as a completely mixed system in which all relevant reactions are described. This model will make it possible to identify processes and reactions that are most significant. The model is based on thermodynamic principles and accounts for all significant heat sources and sinks in landfills. Heat sources include energy from biotic and abiotic reactions and condensation. Heat removal processes include convection of methane and carbon dioxide, infiltration, leachate collection and evaporation. The model was used to evaluate the heat generation performance of aerobic and anaerobic biodegradation of waste with and without the presence of ash (from coal or municipal solid waste). The model analysis showed that the hydration of ash can increase landfill temperature above that predicted for the disposal of municipal solid waste alone.}, number={276}, booktitle={Geotechnical Frontiers 2017}, publisher={American Society of Civil Engineers}, author={Hao, Zisu and Sun, Mei and Ducoste, Joel and Barlaz, Morton}, year={2017}, month={Mar}, pages={281–288} } @article{hao_malyala_dean_ducoste_2017, title={Attenuated Total Reflectance Fourier transform infrared spectroscopy for determination of Long Chain Free Fatty Acid concentration in oily wastewater using the double wavenumber extrapolation technique}, volume={165}, ISSN={["1873-3573"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85009062833&partnerID=MN8TOARS}, DOI={10.1016/j.talanta.2017.01.006}, abstractNote={Long Chain Free Fatty Acids (LCFFAs) from the hydrolysis of fat, oil and grease (FOG) are major components in the formation of insoluble saponified solids known as FOG deposits that accumulate in sewer pipes and lead to sanitary sewer overflows (SSOs). A Double Wavenumber Extrapolative Technique (DWET) was developed to simultaneously measure LCFFAs and FOG concentrations in oily wastewater suspensions. This method is based on the analysis of the Attenuated Total Reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) spectrum, in which the absorbance of carboxyl bond (1710cm-1) and triglyceride bond (1745cm-1) were selected as the characteristic wavenumbers for total LCFFAs and FOG, respectively. A series of experiments using pure organic samples (Oleic acid/Palmitic acid in Canola oil) were performed that showed a linear relationship between the absorption at these two wavenumbers and the total LCFFA. In addition, the DWET method was validated using GC analyses, which displayed a high degree of agreement between the two methods for simulated oily wastewater suspensions (1-35% Oleic acid in Canola oil/Peanut oil). The average determination error of the DWET approach was ~5% when the LCFFA fraction was above 10wt%, indicating that the DWET could be applied as an experimental method for the determination of both LCFFAs and FOG concentrations in oily wastewater suspensions. Potential applications of this DWET approach includes: (1) monitoring the LCFFAs and FOG concentrations in grease interceptor (GI) effluents for regulatory compliance; (2) evaluating alternative LCFFAs/FOG removal technologies; and (3) quantifying potential FOG deposit high accumulation zones in the sewer collection system.}, journal={TALANTA}, author={Hao, Zisu and Malyala, Divya and Dean, Lisa and Ducoste, Joel}, year={2017}, month={Apr}, pages={526–532} } @article{hao_sun_ducoste_benson_luettich_castaldi_barlaz_2017, title={Heat Generation and Accumulation in Municipal Solid Waste Landfills}, volume={51}, ISSN={0013-936X 1520-5851}, url={http://dx.doi.org/10.1021/acs.est.7b01844}, DOI={10.1021/acs.est.7b01844}, abstractNote={There have been reports of North American landfills that are experiencing temperatures in excess of 80-100 °C. However, the processes causing elevated temperatures are not well understood. The objectives of this study were to develop a model to describe the generation, consumption and release of heat from landfills, to predict landfill temperatures, and to understand the relative importance of factors that contribute to heat generation and accumulation. Modeled heat sources include energy from aerobic and anaerobic biodegradation, anaerobic metal corrosion, ash hydration and carbonation, and acid-base neutralization. Heat removal processes include landfill gas convection, infiltration, leachate collection, and evaporation. The landfill was treated as a perfectly mixed batch reactor. Model predictions indicate that both anaerobic metal corrosion and ash hydration/carbonation contribute to landfill temperatures above those estimated from biological reactions alone. Exothermic pyrolysis of refuse, which is hypothesized to be initiated due to a local accumulation of heat, was modeled empirically to illustrate its potential impact on heat generation.}, number={21}, journal={Environmental Science & Technology}, publisher={American Chemical Society (ACS)}, author={Hao, Zisu and Sun, Mei and Ducoste, Joel J. and Benson, Craig H. and Luettich, Scott and Castaldi, Marco J. and Barlaz, Morton A.}, year={2017}, month={Oct}, pages={12434–12442} }