Pub Date : 2024-10-26DOI: 10.1016/j.psep.2024.10.102
Longjin Jiao , Jianguo Chen , Peng Ge , Haoqing Xu , Wenyang Zhang , Nan Zhang , Aizhao Zhou
The urgent need to address barium residue contamination sites is evident. Vertical antifouling barriers effectively prevent the outward spread of pollutants. However, the composition of barrier materials impacts the migration and adsorption behavior of contaminants. To explore the convection-dispersion-adsorption patterns of heavy metal barium in plastic concrete vertical antifouling barriers (comprising GS solidifying material, bentonite, and aggregate) at different mixing ratios, soil column tests and Batch tests were conducted. These tests determined the transport parameters of barium ions under varying bentonite content and water-cement ratios, comparing the retarding factors of barium ions in plastic concrete between the two experiments. The findings suggest that as the water-cement ratio and bentonite content increase, the effective diffusion coefficient and tortuosity factor of chloride ions in the samples also increase. The retarding factors decreases with a higher water-cement ratio but increases with greater bentonite content. Additionally, the retarding factors obtained from the Batch test exceeds that from the soil column test. These research outcomes contribute to optimizing the design of antifouling barriers, enhancing their effectiveness in managing barium residue contamination sites.
{"title":"Study on the migration and adsorption characteristics of barium ions in plastic concrete antifouling barriers","authors":"Longjin Jiao , Jianguo Chen , Peng Ge , Haoqing Xu , Wenyang Zhang , Nan Zhang , Aizhao Zhou","doi":"10.1016/j.psep.2024.10.102","DOIUrl":"10.1016/j.psep.2024.10.102","url":null,"abstract":"<div><div>The urgent need to address barium residue contamination sites is evident. Vertical antifouling barriers effectively prevent the outward spread of pollutants. However, the composition of barrier materials impacts the migration and adsorption behavior of contaminants. To explore the convection-dispersion-adsorption patterns of heavy metal barium in plastic concrete vertical antifouling barriers (comprising GS solidifying material, bentonite, and aggregate) at different mixing ratios, soil column tests and Batch tests were conducted. These tests determined the transport parameters of barium ions under varying bentonite content and water-cement ratios, comparing the retarding factors of barium ions in plastic concrete between the two experiments. The findings suggest that as the water-cement ratio and bentonite content increase, the effective diffusion coefficient and tortuosity factor of chloride ions in the samples also increase. The retarding factors decreases with a higher water-cement ratio but increases with greater bentonite content. Additionally, the retarding factors obtained from the Batch test exceeds that from the soil column test. These research outcomes contribute to optimizing the design of antifouling barriers, enhancing their effectiveness in managing barium residue contamination sites.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"192 ","pages":"Pages 1085-1093"},"PeriodicalIF":6.9,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142587409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-26DOI: 10.1016/j.psep.2024.10.077
Mohammad Alrbai , Sameer Al-Dahidi , Loiy Al-Ghussain , Bashar Shboul , Hassan Hayajneh , Ali Alahmer
Wastewater treatment plants (WWTPs) offer opportunities to optimize resource utilization and enhance energy efficiency. This study provides a comprehensive analysis of using the polygeneration approach in WWTPs to reduce grid energy dependence, optimize energy distribution, and utilize surplus energy for hydrogen (H2) and ammonia (NH3) production. Several models were employed, including photovoltaic (PV) cells, parabolic trough collectors (PTCs), steam methane reforming, and polymer electrolyte membranes, to assess the feasibility of this approach. Three scenarios were evaluated and compared: Scenario 1 (Baseline) represents the current situation, Scenario 2 maximizes the Net Present Value (NPV), and Scenario 3 minimizes NH3 production costs. Real data from As-Samra WWTP in Jordan was used to accurately assess the feasibility of each scenario. The results show that Scenario 2 offers the highest profitability and efficiency, with a NPV of 87.48 million USD and an annual NH3 production of 15,417 tons, reducing both grid dependency and biogas fuel consumption. Both Scenarios 2 and 3 demonstrate the ability to meet thermal demands efficiently while generating significant revenue from NH3 production. Scenario 3, in particular, achieves competitive H2 and NH3 production costs. Environmentally, Scenario 2 significantly reduces annual greenhouse gas emissions by 12.66 kilotons of CO2eq, with near-zero carbon intensity for thermal energy due to solar reliance. In conclusion, the polygeneration approach offers a promising pathway for WWTPs to achieve greater sustainability, economic gains, and reduced environmental impact, providing valuable insights for decision-makers.
{"title":"Assessment of the polygeneration approach in wastewater treatment plants for enhanced energy efficiency and green hydrogen/ammonia production","authors":"Mohammad Alrbai , Sameer Al-Dahidi , Loiy Al-Ghussain , Bashar Shboul , Hassan Hayajneh , Ali Alahmer","doi":"10.1016/j.psep.2024.10.077","DOIUrl":"10.1016/j.psep.2024.10.077","url":null,"abstract":"<div><div>Wastewater treatment plants (WWTPs) offer opportunities to optimize resource utilization and enhance energy efficiency. This study provides a comprehensive analysis of using the polygeneration approach in WWTPs to reduce grid energy dependence, optimize energy distribution, and utilize surplus energy for hydrogen (H<sub>2</sub>) and ammonia (NH<sub>3</sub>) production. Several models were employed, including photovoltaic (PV) cells, parabolic trough collectors (PTCs), steam methane reforming, and polymer electrolyte membranes, to assess the feasibility of this approach. Three scenarios were evaluated and compared: Scenario 1 (Baseline) represents the current situation, Scenario 2 maximizes the Net Present Value (NPV), and Scenario 3 minimizes NH<sub>3</sub> production costs. Real data from As-Samra WWTP in Jordan was used to accurately assess the feasibility of each scenario. The results show that Scenario 2 offers the highest profitability and efficiency, with a NPV of 87.48 million USD and an annual NH<sub>3</sub> production of 15,417 tons, reducing both grid dependency and biogas fuel consumption. Both Scenarios 2 and 3 demonstrate the ability to meet thermal demands efficiently while generating significant revenue from NH<sub>3</sub> production. Scenario 3, in particular, achieves competitive H<sub>2</sub> and NH<sub>3</sub> production costs. Environmentally, Scenario 2 significantly reduces annual greenhouse gas emissions by 12.66 kilotons of CO<sub>2eq</sub>, with near-zero carbon intensity for thermal energy due to solar reliance. In conclusion, the polygeneration approach offers a promising pathway for WWTPs to achieve greater sustainability, economic gains, and reduced environmental impact, providing valuable insights for decision-makers.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"192 ","pages":"Pages 803-821"},"PeriodicalIF":6.9,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-26DOI: 10.1016/j.psep.2024.10.086
Hai Yang , Jin Liu , Bo Zhang , Tao Cheng , Debing Zou , Xing Lv
To effectively remove organic sulfur from coal for higher resource efficiency, an innovative microwave-assisted urea peroxide for desulfurization system was designed. The experimental group with different microwave frequencies and the conventional pyrolysis control group were set up to prove the desulfurization effect of microwave in coordination with urea peroxide. The experimental results showed that under 1000 W microwave irradiation and the promotion of urea peroxide, the desulfurization efficiency can reach 67.29 %, with an increase of 38.32 % while the conventional pyrolysis is only 28.97 %. According to the Fourier transform infrared (FTIR) analysis, the effectiveness of microwave coordination with urea peroxide for desulfurization is explained from macroscopic point of view. Benzylidene thiol, dibenzyl sulfide, and dibenzyl disulfide were selected as model compounds for the quantum chemical calculation. The simulation results demonstrated that the changes in the pathway energy barriers for desulfurization align with the experimental material transformations, confirming the accuracy of the simulation. The sulfur-containing bonds of mercaptans will be destroyed to form hydrogen sulfide, and the undestroyed bonds will remain in the organic matter. After being oxidized, the sulfur-containing bond will break to form a water-soluble sulfonic acid free radical. The unoxidized sulfur bonds of thioethers will be destroyed to generate unstable phenyl free radicals and free sulfur radicals. To achieve stability, phenyl free radicals can pair to form diphenylethane or combine with other radicals (such as •H). In contrast, sulfur free radicals can only react with hydrogen radicals to form hydrogen sulfide. However, the limited availability of hydrogen radicals in the system restricts the desulfurization efficiency. After oxidation by urea peroxide, the thioethers will form sulfones. The sulfur-containing bonds will be fractured and directly generate phenyl and sulfur dioxide, which reduces the dependence on hydrogen free radicals. The three-dimensional desulfurization path of microwave collaboration with urea peroxide experiment was simulated and converted to the analytical bond breaking and formation mechanism. This study proved that microwave synergizes with urea peroxide can intensify the desulfurization process. It provides a high-efficiency method for the clean and green utilization of coal, which is conducive to supporting environmentally sustainable development.
为有效去除煤炭中的有机硫,提高资源利用效率,设计了一种创新的微波辅助过氧化脲脱硫系统。为了证明微波与过氧化脲协同作用的脱硫效果,实验组设置了不同微波频率的实验组和常规热解对照组。实验结果表明,在 1000 W 微波辐照和过氧化脲的促进下,脱硫效率可达 67.29 %,比常规热解提高了 38.32 %,而常规热解仅为 28.97 %。根据傅立叶变换红外(FTIR)分析,微波与过氧化脲配位的脱硫效果从宏观角度得到了解释。量子化学计算选择了亚苄基硫醇、二苄基硫醚和二苄基二硫醚作为模型化合物。模拟结果表明,脱硫路径能垒的变化与实验材料的转化一致,证实了模拟的准确性。硫醇的含硫键会被破坏形成硫化氢,未被破坏的键会留在有机物中。被氧化后,含硫键会断裂,形成水溶性磺酸自由基。硫醚中未氧化的硫键会被破坏,生成不稳定的苯基自由基和游离硫自由基。为了达到稳定性,苯基自由基可以配对形成二苯基乙烷或与其他自由基(如-H)结合。相反,硫自由基只能与氢自由基反应生成硫化氢。然而,系统中氢自由基的有限性限制了脱硫效率。过氧化脲氧化后,硫醚会形成砜。含硫键断裂后会直接生成苯基和二氧化硫,从而减少了对氢自由基的依赖。模拟了微波协同过氧化脲实验的三维脱硫路径,并将其转换为分析键的断裂和形成机理。该研究证明,微波与过氧化脲协同作用可强化脱硫过程。它为煤的清洁绿色利用提供了一种高效方法,有利于支持环境可持续发展。
{"title":"Mechanism of microwave-assisted coal desulfurization with urea peroxide","authors":"Hai Yang , Jin Liu , Bo Zhang , Tao Cheng , Debing Zou , Xing Lv","doi":"10.1016/j.psep.2024.10.086","DOIUrl":"10.1016/j.psep.2024.10.086","url":null,"abstract":"<div><div>To effectively remove organic sulfur from coal for higher resource efficiency, an innovative microwave-assisted urea peroxide for desulfurization system was designed. The experimental group with different microwave frequencies and the conventional pyrolysis control group were set up to prove the desulfurization effect of microwave in coordination with urea peroxide. The experimental results showed that under 1000 W microwave irradiation and the promotion of urea peroxide, the desulfurization efficiency can reach 67.29 %, with an increase of 38.32 % while the conventional pyrolysis is only 28.97 %. According to the Fourier transform infrared (FTIR) analysis, the effectiveness of microwave coordination with urea peroxide for desulfurization is explained from macroscopic point of view. Benzylidene thiol, dibenzyl sulfide, and dibenzyl disulfide were selected as model compounds for the quantum chemical calculation. The simulation results demonstrated that the changes in the pathway energy barriers for desulfurization align with the experimental material transformations, confirming the accuracy of the simulation. The sulfur-containing bonds of mercaptans will be destroyed to form hydrogen sulfide, and the undestroyed bonds will remain in the organic matter. After being oxidized, the sulfur-containing bond will break to form a water-soluble sulfonic acid free radical. The unoxidized sulfur bonds of thioethers will be destroyed to generate unstable phenyl free radicals and free sulfur radicals. To achieve stability, phenyl free radicals can pair to form diphenylethane or combine with other radicals (such as •H). In contrast, sulfur free radicals can only react with hydrogen radicals to form hydrogen sulfide. However, the limited availability of hydrogen radicals in the system restricts the desulfurization efficiency. After oxidation by urea peroxide, the thioethers will form sulfones. The sulfur-containing bonds will be fractured and directly generate phenyl and sulfur dioxide, which reduces the dependence on hydrogen free radicals. The three-dimensional desulfurization path of microwave collaboration with urea peroxide experiment was simulated and converted to the analytical bond breaking and formation mechanism. This study proved that microwave synergizes with urea peroxide can intensify the desulfurization process. It provides a high-efficiency method for the clean and green utilization of coal, which is conducive to supporting environmentally sustainable development.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"192 ","pages":"Pages 1127-1137"},"PeriodicalIF":6.9,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142587407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-26DOI: 10.1016/j.psep.2024.10.103
Jun Wan , Runnian Gao , Xiaonan Feng
Non-reactive phosphorus (e.g., phosphonate) contributes to eutrophication, while little attention has been paid to its control. The iron-based materials are highly efficient in orthophosphate removal from water, while the correlation between their physicochemical properties and selective phosphonate (e.g. Nitrilotri(methylphosphonic acid) (NTMP)) adsorption is still unclear. In this study, Fe3O4 (magnetite), FeOOH (goethite) and Fe2O3 (hematite) with different crystal structures, particle sizes and surface area were synthesized for NTMP adsorption. The physicochemical properties of the three kinds of iron oxides were characterized. The batch experiments were applied to explore the NTMP adsorption and desorption performance. The maximum adsorption capacity of NTMP on Fe3O4, FeOOH and Fe2O3 were 4.14, 1.91 and 0.99 mg-P/g, respectively. Results implied the crystal structure and surface area of iron oxides determined the maximum NTMP adsorption capacity. The NTMP adsorption on the three iron oxides was spontaneous, endothermic and randomness increase. The iron oxides showed high selectivity towards NTMP adsorption in water containing anions, while the co-existing Ca2+ and Mg2+ remarkably increased the adsorption capacity. The successive adsorption-desorption cycles suggested a favorable reusability of the above iron oxides and a high NTMP desorption efficiency. The specific NTMP adsorption capacity followed the sequence of FeOOH > Fe2O3 > Fe3O4, and was highly dependent on surface OH− proportion. The NTMP adsorption mechanism was mainly attributed to inner-sphere complexation. This study provides insights into the iron-based adsorbents design for selective phosphonate adsorption in the future.
{"title":"Insights into the relationship between Nitrilotri(methylphosphonic acid) (NTMP) adsorption and physicochemical properties of iron oxides","authors":"Jun Wan , Runnian Gao , Xiaonan Feng","doi":"10.1016/j.psep.2024.10.103","DOIUrl":"10.1016/j.psep.2024.10.103","url":null,"abstract":"<div><div>Non-reactive phosphorus (e.g., phosphonate) contributes to eutrophication, while little attention has been paid to its control. The iron-based materials are highly efficient in orthophosphate removal from water, while the correlation between their physicochemical properties and selective phosphonate (e.g. Nitrilotri(methylphosphonic acid) (NTMP)) adsorption is still unclear. In this study, Fe<sub>3</sub>O<sub>4</sub> (magnetite), FeOOH (goethite) and Fe<sub>2</sub>O<sub>3</sub> (hematite) with different crystal structures, particle sizes and surface area were synthesized for NTMP adsorption. The physicochemical properties of the three kinds of iron oxides were characterized. The batch experiments were applied to explore the NTMP adsorption and desorption performance. The maximum adsorption capacity of NTMP on Fe<sub>3</sub>O<sub>4</sub>, FeOOH and Fe<sub>2</sub>O<sub>3</sub> were 4.14, 1.91 and 0.99 mg-P/g, respectively. Results implied the crystal structure and surface area of iron oxides determined the maximum NTMP adsorption capacity. The NTMP adsorption on the three iron oxides was spontaneous, endothermic and randomness increase. The iron oxides showed high selectivity towards NTMP adsorption in water containing anions, while the co-existing Ca<sup>2+</sup> and Mg<sup>2+</sup> remarkably increased the adsorption capacity. The successive adsorption-desorption cycles suggested a favorable reusability of the above iron oxides and a high NTMP desorption efficiency. The specific NTMP adsorption capacity followed the sequence of FeOOH > Fe<sub>2</sub>O<sub>3</sub> > Fe<sub>3</sub>O<sub>4</sub>, and was highly dependent on surface OH<sup>−</sup> proportion. The NTMP adsorption mechanism was mainly attributed to inner-sphere complexation. This study provides insights into the iron-based adsorbents design for selective phosphonate adsorption in the future.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"192 ","pages":"Pages 750-759"},"PeriodicalIF":6.9,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-26DOI: 10.1016/j.psep.2024.10.074
Mehmet Kaptan, Ozan Bayazit
The most prevalent types of ship accidents in port areas are allisions, collisions, and groundings. A comprehensive risk assessment is needed to prevent and mitigate these accidents and their consequences. This study evaluates the risk of such accidents in port areas by presenting a model that elucidates the relationship between risk-identifying factors (RIFs) and accident severity. In this context, the RIFs are determined by analyszing the reports of 528 accidents that occurred in port areas between 1995 and 2023. Subsequently, the model is created by analysing the data derived from these reports using the Tree Augmented Naive Bayes (TAN) algorithm, which is an approach of the data-driven Bayesian network method. The findings of the study indicate that accident type, wind, ship age, and vessel type are the most influential factors in predicting the severity of accidents in port areas. It is thought that the model will assist port authorities in identifying operational risks contributing to accidents and in formulating preventive regulations.
{"title":"Data-driven Bayesian risk assessment of factors influencing the severity of marine accidents in port areas","authors":"Mehmet Kaptan, Ozan Bayazit","doi":"10.1016/j.psep.2024.10.074","DOIUrl":"10.1016/j.psep.2024.10.074","url":null,"abstract":"<div><div>The most prevalent types of ship accidents in port areas are allisions, collisions, and groundings. A comprehensive risk assessment is needed to prevent and mitigate these accidents and their consequences. This study evaluates the risk of such accidents in port areas by presenting a model that elucidates the relationship between risk-identifying factors (RIFs) and accident severity. In this context, the RIFs are determined by analyszing the reports of 528 accidents that occurred in port areas between 1995 and 2023. Subsequently, the model is created by analysing the data derived from these reports using the Tree Augmented Naive Bayes (TAN) algorithm, which is an approach of the data-driven Bayesian network method. The findings of the study indicate that accident type, wind, ship age, and vessel type are the most influential factors in predicting the severity of accidents in port areas. It is thought that the model will assist port authorities in identifying operational risks contributing to accidents and in formulating preventive regulations.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"192 ","pages":"Pages 1094-1109"},"PeriodicalIF":6.9,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142587458","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-24DOI: 10.1016/j.psep.2024.10.063
Zixiang Gao , Guoqiang Li , Jun Liu , Guojie Zhang , Yuqiong Zhao , Ying Wang
The design and construction of catalysts featuring abundant electron transfer and defect structures for the regeneration of styrene-saturated activated carbon (AC) pose a significant challenge. This paper presents successful preparation of a regenerated adsorbent with synergistic catalytic active sites of NiCo2O4 spinel and carbon defects using a simple impregnation method. Enhanced catalytic activity is attributed to the electronic synergy between NiCo2O4 and carbon defects in 2.5Ni-2.5Co-900, involving substantial electron transfers, abundant acidic sites, and strong reducibility. Reactive oxygen species and the robust oxygen transfer facilitate the deep oxidation of intermediates and carbon elimination. The optimized regenerated adsorbent achieved a styrene adsorption capacity of 446.4 mg/g with a recovery of 92.4 % of the fresh sample, which is 1.5 times higher than 5Ni-900 and about 1.8 times higher than the unmodified regenerated activated carbon sample, RAC-900. The mechanism of styrene cracking and the evolution of intermediates were investigated using thermogravimetric-infrared coupling, and the effects of catalytic temperature and active sites on styrene cracking, deep oxidation of intermediates, and elimination of carbon deposits were explored. Kinetic analysis demonstrated that the adsorption of styrene on regenerated samples entailed a multifaceted process integrating both physical and chemical adsorption. The significance of chemical adsorption became increasingly evident as the concentration of defective sites grew. Intra-pore diffusion is the main determining step of the adsorption process. After five cycles, the adsorption capacity of 2.5Ni-2.5Co-900 decreased to below 25 %, suggesting promising strategies to overcome challenges of regenerating styrene-saturated AC.
{"title":"Electronic synergy between NiCo2O4 and adjacent carbon defects to enhance styrene cracking activity for styrene-saturated activated carbon regeneration","authors":"Zixiang Gao , Guoqiang Li , Jun Liu , Guojie Zhang , Yuqiong Zhao , Ying Wang","doi":"10.1016/j.psep.2024.10.063","DOIUrl":"10.1016/j.psep.2024.10.063","url":null,"abstract":"<div><div>The design and construction of catalysts featuring abundant electron transfer and defect structures for the regeneration of styrene-saturated activated carbon (AC) pose a significant challenge. This paper presents successful preparation of a regenerated adsorbent with synergistic catalytic active sites of NiCo<sub>2</sub>O<sub>4</sub> spinel and carbon defects using a simple impregnation method. Enhanced catalytic activity is attributed to the electronic synergy between NiCo<sub>2</sub>O<sub>4</sub> and carbon defects in 2.5Ni-2.5Co-900, involving substantial electron transfers, abundant acidic sites, and strong reducibility. Reactive oxygen species and the robust oxygen transfer facilitate the deep oxidation of intermediates and carbon elimination. The optimized regenerated adsorbent achieved a styrene adsorption capacity of 446.4 mg/g with a recovery of 92.4 % of the fresh sample, which is 1.5 times higher than 5Ni-900 and about 1.8 times higher than the unmodified regenerated activated carbon sample, RAC-900. The mechanism of styrene cracking and the evolution of intermediates were investigated using thermogravimetric-infrared coupling, and the effects of catalytic temperature and active sites on styrene cracking, deep oxidation of intermediates, and elimination of carbon deposits were explored. Kinetic analysis demonstrated that the adsorption of styrene on regenerated samples entailed a multifaceted process integrating both physical and chemical adsorption. The significance of chemical adsorption became increasingly evident as the concentration of defective sites grew. Intra-pore diffusion is the main determining step of the adsorption process. After five cycles, the adsorption capacity of 2.5Ni-2.5Co-900 decreased to below 25 %, suggesting promising strategies to overcome challenges of regenerating styrene-saturated AC.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"192 ","pages":"Pages 719-737"},"PeriodicalIF":6.9,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142535088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-24DOI: 10.1016/j.psep.2024.10.093
Guocui Li , Keqing Li , Tong Zhao , Siqi Zhang , Deping Chen , Zeping Wu , Bo Zhang , Guodong Yang , Wen Ni
Barium slag (BS) and municipal solid waste incineration fly ash (MSWI FA) are hazardous wastes produced in large quantities, with heavy metals such as Ba, Pb, and Cr significantly exceeding acceptable levels, posing a threat to the ecological environment and living organisms. The development of technologies for the harmless disposal and resource utilization of hazardous waste is a current research focus. This study used BS, blast furnace slag (BFS), MSWI FA, and flue gas desulphurized (FGD) gypsum to replace cement in the preparation of solid waste-based binder. The results indicated that the optimal mass ratio was BS: BFS: FGD gypsum: MSWI FA = 14 %:56 %:20 %:10 %. The compressive strengths of the binder at 3, 7,and 28 days were 23.7 MPa, 30.76 MPa, and 38.65 MPa, respectively. Chinese standard HJ557–2010 was adopted to carry out heavy metal leaching experiment on raw materials, the immobilization efficiency of heavy metals Ba, Pb, and Cr were 99 %, 99 %, and 96 %, respectively, and the leachate toxicity was below the Class III groundwater limit. XRD, FT-IR, TG-DSC, XPS, SEM-EDS and other experimental methods were used to study the effect of BS content on the properties of cementable materials. An appropriate amount of BS hydrolyzes during hydration, releasing Ba²⁺ and OH⁻ ions, which activated the BFS, producing AFt and C–(A)–S–H gel. These products interweaved with material particles to fill the pore spaces, enhancing the binder’s mechanical strength and heavy metal immobilization capability. However, when excessive BS was added, the hydration products favored the formation of FS, leading to a decline in binder performance.
{"title":"Performance and hydration mechanism of MSWI FA-barium slag-based all-solid waste binder","authors":"Guocui Li , Keqing Li , Tong Zhao , Siqi Zhang , Deping Chen , Zeping Wu , Bo Zhang , Guodong Yang , Wen Ni","doi":"10.1016/j.psep.2024.10.093","DOIUrl":"10.1016/j.psep.2024.10.093","url":null,"abstract":"<div><div>Barium slag (BS) and municipal solid waste incineration fly ash (MSWI FA) are hazardous wastes produced in large quantities, with heavy metals such as Ba, Pb, and Cr significantly exceeding acceptable levels, posing a threat to the ecological environment and living organisms. The development of technologies for the harmless disposal and resource utilization of hazardous waste is a current research focus. This study used BS, blast furnace slag (BFS), MSWI FA, and flue gas desulphurized (FGD) gypsum to replace cement in the preparation of solid waste-based binder. The results indicated that the optimal mass ratio was BS: BFS: FGD gypsum: MSWI FA = 14 %:56 %:20 %:10 %. The compressive strengths of the binder at 3, 7,and 28 days were 23.7 MPa, 30.76 MPa, and 38.65 MPa, respectively. Chinese standard HJ557–2010 was adopted to carry out heavy metal leaching experiment on raw materials, the immobilization efficiency of heavy metals Ba, Pb, and Cr were 99 %, 99 %, and 96 %, respectively, and the leachate toxicity was below the Class III groundwater limit. XRD, FT-IR, TG-DSC, XPS, SEM-EDS and other experimental methods were used to study the effect of BS content on the properties of cementable materials. An appropriate amount of BS hydrolyzes during hydration, releasing Ba²⁺ and OH⁻ ions, which activated the BFS, producing AFt and C–(A)–S–H gel. These products interweaved with material particles to fill the pore spaces, enhancing the binder’s mechanical strength and heavy metal immobilization capability. However, when excessive BS was added, the hydration products favored the formation of FS, leading to a decline in binder performance.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"192 ","pages":"Pages 588-599"},"PeriodicalIF":6.9,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142535343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-24DOI: 10.1016/j.psep.2024.09.122
K. Vijaya Bhaskar , Mohammad Rashed , K. Subrahmanya Bhat , Jechan Lee , Ki-Hyun Kim , Kezia Buruga
Continuous flow processing has become a key technology to maximize the capabilities of chemical syntheses. Numerous new tactics have been devised to synthesize various chemicals including active pharmaceutical ingredients (APIs) via a continuous flow system using microreactors. This review aims to illustrate the holistic system approach and diverse applications of continuous flow microreactors for the synthesis of APIs (with respect to type, design, and fabrication). This review also highlights the applicability of continuous flow microreactors in the synthesis of APIs in contrast to conventional batch-type methods along with a discussion of their merits and demerits. Overall, this review is expected to offer valuable insights into the utility of continuous flow microreactor technology for the upscaled production of commercially feasible APIs.
{"title":"A continuous flow microreactor as a practical tool for the synthesis of active pharmaceutical ingredients","authors":"K. Vijaya Bhaskar , Mohammad Rashed , K. Subrahmanya Bhat , Jechan Lee , Ki-Hyun Kim , Kezia Buruga","doi":"10.1016/j.psep.2024.09.122","DOIUrl":"10.1016/j.psep.2024.09.122","url":null,"abstract":"<div><div>Continuous flow processing has become a key technology to maximize the capabilities of chemical syntheses. Numerous new tactics have been devised to synthesize various chemicals including active pharmaceutical ingredients (APIs) via a continuous flow system using microreactors. This review aims to illustrate the holistic system approach and diverse applications of continuous flow microreactors for the synthesis of APIs (with respect to type, design, and fabrication). This review also highlights the applicability of continuous flow microreactors in the synthesis of APIs in contrast to conventional batch-type methods along with a discussion of their merits and demerits. Overall, this review is expected to offer valuable insights into the utility of continuous flow microreactor technology for the upscaled production of commercially feasible APIs.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"192 ","pages":"Pages 437-449"},"PeriodicalIF":6.9,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142535387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study investigated the effect of 2-bromo-3,3,3-trifluoropropene (2-BTP, C3H2BrF3) on hydrogen explosion behavior through a combination of experiments and simulations. The maximum explosion pressure (pmax), maximum pressure rise rate ((dp/dt)max), and critical inhibition concentration (CIC), across different equivalence ratios (Φ) and inhibitor concentrations (V), were obtained via experiments. The changes in adiabatic flame temperature, mole fraction of active radicals and sensitivity coefficient throughout the reaction were analyzed using CHEMKIN. The fuel-like properties of 2-BTP and the carbon monoxide (CO) produced by decomposition led to a promoting effect on the lean hydrogen explosion, primarily due to the elementary reactions R31, R806 and R882. When Φ≥1.0, the capture of active radicals via elementary reactions such as R908, R1507, and R88 was enhanced, resulting in the dominance of inhibition and a corresponding inhibitory effect. Notably, 2-BTP exhibited an inhibitory effect for (dp/dt)max at any equivalence ratio. The CIC decreased from 10 % to 4 % when increasing equivalence ratios from 0.6 to 2.0. This work provides crucial data and a theoretical foundation for the prevention and control of hydrogen explosions.
{"title":"Investigation on the inhibition effect and mechanism of hydrogen explosion by 2-bromo-3,3,3-trifluoropropene","authors":"Zhangqiang Dong, Wei Gao, Jiaxing Zhang, Jiafeng Cheng, Yufeng Wu","doi":"10.1016/j.psep.2024.10.094","DOIUrl":"10.1016/j.psep.2024.10.094","url":null,"abstract":"<div><div>This study investigated the effect of 2-bromo-3,3,3-trifluoropropene (2-BTP, C<sub>3</sub>H<sub>2</sub>BrF<sub>3</sub>) on hydrogen explosion behavior through a combination of experiments and simulations. The maximum explosion pressure (<em>p</em><sub>max</sub>), maximum pressure rise rate ((d<em>p</em>/d<em>t</em>)<sub>max</sub>), and critical inhibition concentration (CIC), across different equivalence ratios (<em>Φ</em>) and inhibitor concentrations (<em>V</em>), were obtained via experiments. The changes in adiabatic flame temperature, mole fraction of active radicals and sensitivity coefficient throughout the reaction were analyzed using CHEMKIN. The fuel-like properties of 2-BTP and the carbon monoxide (CO) produced by decomposition led to a promoting effect on the lean hydrogen explosion, primarily due to the elementary reactions R31, R806 and R882. When <em>Φ</em>≥1.0, the capture of active radicals via elementary reactions such as R908, R1507, and R88 was enhanced, resulting in the dominance of inhibition and a corresponding inhibitory effect. Notably, 2-BTP exhibited an inhibitory effect for (d<em>p</em>/d<em>t</em>)<sub>max</sub> at any equivalence ratio. The CIC decreased from 10 % to 4 % when increasing equivalence ratios from 0.6 to 2.0. This work provides crucial data and a theoretical foundation for the prevention and control of hydrogen explosions.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"192 ","pages":"Pages 660-668"},"PeriodicalIF":6.9,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142535085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The effects of water mist with different diameters and mass loadings on hydrogen auto-ignition in air with elevated temperatures and pressures are studied. It is shown that smaller droplets with larger mass loading are the most effective in inhibiting the auto-ignition process. Under elevated initial pressures and temperatures, the role of water mist in impacting auto-ignition is minimal, primarily because the ignition delay is substantially shorter than the droplet evaporation duration. As the initial temperature decreases, there exists a temperature value below which water mist markedly extends the ignition delay time, even escalating it by up to two orders of magnitude or causing a complete suppression of ignition. The rate of production for important radicals was analyzed. The data indicates that the evaporation of the water mist lowers the initial temperature, leading to a reduction in the rate of the temperature-sensitive fast chain branching reaction. In contrast, the third body reaction that generates HO2 is not sensitive to temperature. Meanwhile, the introduction of H2O results in an earlier activation of the third body reactions. Consequently, the production of HO2 is enhanced, emphasizing the role of subsequent slow chain propagation reactions that generate OH, thereby extending the ignition delay. By deactivating the mass transfer between two phases and introducing artificial species, it is evident that water vapor dilution and thermal effects predominantly influence the ignition delay, while its role as a direct reactant is minimal.
{"title":"Effects of water sprays on hydrogen autoignition in heated air","authors":"Zijun Wang , Xiaolong Gou , Qingyang Meng , Huangwei Zhang","doi":"10.1016/j.psep.2024.10.069","DOIUrl":"10.1016/j.psep.2024.10.069","url":null,"abstract":"<div><div>The effects of water mist with different diameters and mass loadings on hydrogen auto-ignition in air with elevated temperatures and pressures are studied. It is shown that smaller droplets with larger mass loading are the most effective in inhibiting the auto-ignition process. Under elevated initial pressures and temperatures, the role of water mist in impacting auto-ignition is minimal, primarily because the ignition delay is substantially shorter than the droplet evaporation duration. As the initial temperature decreases, there exists a temperature value below which water mist markedly extends the ignition delay time, even escalating it by up to two orders of magnitude or causing a complete suppression of ignition. The rate of production for important radicals was analyzed. The data indicates that the evaporation of the water mist lowers the initial temperature, leading to a reduction in the rate of the temperature-sensitive fast chain branching reaction. In contrast, the third body reaction that generates HO<sub>2</sub> is not sensitive to temperature. Meanwhile, the introduction of H<sub>2</sub>O results in an earlier activation of the third body reactions. Consequently, the production of HO<sub>2</sub> is enhanced, emphasizing the role of subsequent slow chain propagation reactions that generate OH, thereby extending the ignition delay. By deactivating the mass transfer between two phases and introducing artificial species, it is evident that water vapor dilution and thermal effects predominantly influence the ignition delay, while its role as a direct reactant is minimal.</div></div>","PeriodicalId":20743,"journal":{"name":"Process Safety and Environmental Protection","volume":"192 ","pages":"Pages 915-925"},"PeriodicalIF":6.9,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142573162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}