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This paper presents a newly proposed generic framework for unifying different industrial by-products (IBPs) as composite binders to potentially replace ordinary Portland cement (OPC) for soft clay stabilization. The concepts of three chemical moduli (TCM) and strength activity index (SAI) are used to determine the fractions of different IBPs, and the final design mix is further tuned by adding gypsum for additional strength gain contributed by density due to ettringite formation. As a case study, a coastal soft clay was stabilized by different IBPs and gypsum using the new generic framework. Results show that the highest unconfined compression strengths of the IBPs stabilized clay cured for 7, 28, and 60 days reach 0.75, 1.21, and 1.39 MPa, respectively, which are even higher than those of the OPC-stabilized counterparts, suggesting the possibility of using IBPs to substitute OPC. Moreover, the additive gypsum plays a beneficial role for more strength gain due to the formation and volumetric expansion of ettringite. The implementation strategy for the new framework is recommended, and its practical implications for soil stabilization are discussed in terms of IBPs recycling and reuse, environmental sustainability, and economic benefits. • A generic framework was proposed to enable multiple IBPs for soft clay stabilization. • TCM originally developed for the cement clinker is also applicable to IBPs-based binders. • The combination of TCM and SAI is applicable and effective in IBPs-based clay stabilization. • Gypsum plays a beneficial role for more strength gain due to the formation and volumetric expansion of ettringite. [ABSTRACT FROM AUTHOR]

It is important to investigate the feasibility of reclaimed water irrigation for fulfilling cleaner production of salt-tolerant vegetables in coastal saline soils which widely distribute in the world. Reclaimed water irrigation might cause the accumulation of endocrine disrupting chemicals in crops although it is a good approach for alleviating water resource shortage. This study firstly investigated the possible cleaner production and benefits of cultivating Mesembryanthemum crystallinum (M. crystallinum) in coastal saline soil irrigated by simulated reclaimed water. Concentrations of target pollutants including bisphenol A (BPA) and nonylphenol (NP) in root of M. crystallinum were higher than those in stem and leaf while soil salinity could increase the concentrations of BPA/NP in root and decrease those in leaf and stem. The highest concentration of BPA/NP in root of M. crystallinum growing in soil with salt content of 7.2‰ reached 29.28/243.47 μg/kg. BPA mainly accumulated in leaf of M. crystallinum with the highest amount of 621.93 ng under non-saline conditions while NP mainly accumulated in root with the highest amount of 1114.57 ng under saline conditions. The hazard quotients sharply decreased by >50% when the soil salinity increased from 1.1‰ to 7.2‰. Non-cancer health risks of BPA and NP in M. crystallinum were acceptable for all human groups while the daily intake of BPA/NP was much lower than the corresponding tolerant daily intake. Life cycle assessment illustrated that M. crystallinum cultivation in soil with salt content of 1.1‰ posed the lowest environmental burden. Salt-tolerant vegetables such as M. crystallinum would be recommended to be cultivated in low-salinity saline soils using reclaimed water irrigation due to lower pollutant accumulation and environmental burden to achieve the goals of cleaner vegetable production. These findings provide new insight on the promising potential of reclaimed water irrigation and crop cultivation in saline soils in coastal regions. • Salt-tolerance crop was grown in coastal saline soil with reclaimed water irrigation. • Soil salinity decreased accumulation of BPA and NP in Mesembryanthemum crystallinum. • Increased soil salinity alleviated the health risks caused by EDCs accumulation. • Crop cultivation in slight saline soil posed the lowest environmental burden. • Crop production irrigated with reclaimed water was promising for saline soil usage. [ABSTRACT FROM AUTHOR]

A deep understanding of the environmental behavior of polycyclic aromatic hydrocarbons (PAHs) in combined sewer overflows (CSOs) is essential for evaluating and mitigating PAHs in the urban environment. This study characterized occurrence of 16 PAHs in CSOs, the source of which were analyzed by the positive matrix factorization (PMF) models and the self-organizing map (SOM). The adverse effects of 16 PAHs in CSOs on the microbial diversity and functional gene of the receiving water sediments were analyzed through Illumina MiSeq sequencing and PICRUSt2 platform. The results showed that due to the relatively low vapor pressure and easy adsorption on particles, the proportion of tetracyclic PAHs was the highest among 16 PAHs from the CSOs with an average value of 42.5%. The first flush effect of PAHs had been found in each rainfall event. However, there was no significant correlation between the first flush effect and the rainfall characteristics. In terms of source apportionment, the SOM and PMF models identified vehicular emissions as the predominant source of particulate PAHs from the CSOs, which accounted for ≥54.8% of the total PAHs. ∑ 16 PAHs levels in the river sediment were directly affected by two gravity pipe outlets and three pumping station outlets, which were significantly higher than the control points. Besides, PAHs with different benzene rings had a significant correlation with specific microbial populations. The PAH related genes were also specifically affected by the CSO events. Therefore, through the observation of gene function, we could better find the specific impact of CSOs on the river's ecological environment. • The proportion of tetracyclic PAHs was the highest among 16 PAHs from the CSOs. • The first flush effect of PAHs had been found in each rainfall event. • Vehicular emissions are the predominant source of particulate PAHs from the CSOs. • The PAH related genes were specifically affected by CSOs in the river sediments. [ABSTRACT FROM AUTHOR]

Abstract Flue gas denitration systems play an important role in reducing nitrogen oxide emissions. However, their potential resource efficiency, environmental impacts and economic performance should be emphasized. It is necessary to assess their effects from pros and cons so as to reflect their relatively sustainable levels more completely. Since emergy analysis (EmA) considers quality differences among diverse categories of energy, materials and money, as well as the environmental contribution to economic activities, this work put forward an emergy-based combined approach and related indicators, which consider pollution emissions' impacts, for evaluating flue gas denitration systems comprehensively. Next, two flue gas denitration systems in China (the selective catalytic reduction denitration system (SCRDS) and the selective non-catalytic reduction denitration system (SNCRDS)), as study cases, were investigated using the proposed approach and indicators. It is found that (1) purchased nonrenewable input (NP) contributes most to their total emergy input (TE); (2) the emergy loss is main emissions' impact; (3) the SNCRDS has higher environmental cost but lower economic cost than the SCRDS due to its smaller share of purchased input and lower treatment efficiency; (4) the SCRDS has much higher environmental loading than the SNCRDS due to its higher share of nonrenewable input; (5) the SNCRDS has higher sustainability level than the SCRDS due to its lower dependence on nonrenewable input. Generally the denitration technologies convert lots of purchased nonrenewable resources into the local environmental benefits in an unsustainable way, which could cause the depletion of nonrenewable resources and environmental emissions in other areas in the future. Finally, some suggestions are proposed, including replacing the reducing agent for the SNCRDS, promoting the regeneration of spent denitration catalysts, strengthening energy management, and emphasizing operation training of technical staff. Graphical abstract Image Highlights • The performances of two flue gas denitration systems were investigated. • Purchased nonrenewable input has the largest contribution to their total emergy input. • The Selective Catalytic Reduction Denitration System has relatively lower emergy cost but higher economic cost. • The Selective Non-Catalytic Reduction Denitration System has relatively higher sustainability level. • The two systems convert lots of nonrenewable resources into the local environmental benefits in an unsustainable way. [ABSTRACT FROM AUTHOR]

Proper reuse of phosphogypsum (PG) can mitigate the potential risks to humans and environment caused by improper disposal. Therefore, exploration of PG reuse schemes is necessary based on environmental performance, energy consumption, greenhouse gas emissions, and economic benefits. Few studies have investigated this issue considering these four aspects simultaneously; thus, such studies cannot provide sufficient decision-making information. This study proposes an integrated approach, composed of emergy-based indicators, energy consumption intensity, carbon emissions intensity, and economic indicators, as well as a comprehensive index, specifically, the synergy degree index, to compare waste reuse schemes for more complete decision-making. A building materials production enterprise that uses PG as the main raw material has four product systems, namely, the building gypsum powder system (BGPS), new wall material system (NWMS), plaster cavity floor system (PCFS), and dry-mixed mortar system (DMS). These systems were used as a case study and investigated using a specific approach presented in this study. The research results show that the BGPS has the most reasonable resource structure; it has the highest environmental sustainability and also the highest energy consumption and carbon emission intensities, while the PCFS has the highest production efficiency and the largest environmental load. The BGPS has the highest environmental sustainability. The DMS has the best economic benefit and generally exhibits the best comprehensive performance. Therefore, DMS use should further increase environmental sustainability of PG in the future. [Display omitted] • Phosphogypsum resources reuse schemes are compared through Synergetic degree index. • The building gypsum powder system (BGPS) has the best emergy sustainability (36.32). • BGPS has the most energy use (3.95E07 J/USD) and carbon emission (5.27 kg CO2-e/USD). • The dry-mixed mortar system (DMS) has the largest net economic benefit ratio (8.98). • DMS is the best one in the four systems based on its Synergetic degree index (7.05). [ABSTRACT FROM AUTHOR]

Our study synthesized La(OH) 3 decorated co-graft tannin and polyethyleneimine (PEI) co-coating magnetic composites (La@TP@Fe 3 O 4). Dual organic modification with co-grafted tannin and PEI can significantly enhance the material's charge density, allowing La@TP@Fe 3 O 4 to maintain a high phosphate adsorbability at a wide pH range (3.0–11.0). La@TP@Fe 3 O 4 achieved a maximum theoretical phosphate adsorption capacity of 363.64 mg/g at 25 °C under pH 3.0 and was consistent with the Langmuir model, reaching adsorption equilibrium in 20 min. Phosphate adsorption was less affected by various coexisting ions with >90% of phosphate removal maintained after five cycles. La@TP@Fe 3 O 4 could be quickly separated by magnetic force with negligible La and Fe leakages. Besides electrostatic attraction, inner-sphere complexation and weak precipitation contributed to phosphate uptake on La@TP@Fe 3 O 4 , as demonstrated by X-ray absorption near edge structure (XANES) analysis. Importantly, low La@TP@Fe 3 O 4 doses could quickly decrease phosphate concentrations in natural water and wastewater to meet regulatory requirements, thus highlighting the potential applicability of La@TP@Fe 3 O 4 for phosphate removal. [Display omitted] • La(OH) 3 decorated co-graft tannin and PEI co-coating magnetic composite was prepared. • La@TP@Fe 3 O 4 exhibited superior P adsorbability at a wide pH range of 3.0–11.0 • High P adsorption capacity (363.64 mg/g) and fast adsorption kinetics were achieved. • XANES spectra confirmed phosphate association with lanthanum (La–P) on La@TP@Fe 3 O 4. • Phosphate discharge standards were efficiently met in natural water and wastewater. [ABSTRACT FROM AUTHOR]

In this study, a staged and efficient advanced treatment process for combined antibiotics and heavy ion pollution based on a designed electrochemical double-chamber system using three-dimensional reduced graphene as the electrode material was established. Tetracycline (TC) and copper ions as the common pollutants in the tailwater of livestock wastewater were chosen as representative antibiotics and heavy ions. A high removal efficiency of almost 100% of tetracycline and copper ions at low concentrations (10 mg/L) was obtained using the electrochemical double-chamber system. Under the optimal reaction conditions, the estimated energy consumption was 0.25 KWhm−3. Among the 20 mg/L and 50 mg/L composite pollutants, the removal efficiencies of tetracycline were 92% and 82%, respectively, and the removal efficiencies of copper ions were 99% and 100%, respectively. In the treatment of actual tailwater from livestock wastewater, the removal efficiencies of copper ions and total organic carbon (TOC) were 89% and 63%, respectively. In the same treatment time, compared to a single-chamber reaction system, the TC removal efficiencies increased by 13%, 20%, and 26%, and the removal efficiencies of Cu2+ increased by 28%, 48%, and 41% in the treatment of 10 mg/L, 20 mg/L, and 50 mg/L composite pollutants, respectively. In addition, the staged disposal method based on the electrochemical double-chamber system had a higher efficiency and double the treatment capacity for removing combined tetracycline and copper ion pollution than a general electrochemistry system in an equal time period. This study offers a practical and efficient treatment system for combined pollution in water. [Display omitted] • A double-chamber electrochemistry system was established. • The prepared 3D rGO foams were used as multifunctional electrodes. • 3D rGO could enrich and degrade the low-concentrated TC-Cu combined pollution. • The removal paths of pollutants in the same time unit were diversified. • A high removal efficiency of pollutants in actual tailwater could be obtained. [ABSTRACT FROM AUTHOR]

Controlled release nitrogen fertilizers (CRNF) possess good nutrient release performance and application prospects. Under the dual pressures of food security and environmental protection, whether substitution of urea using CRNF could improve environmental sustainability of rice production relative to the utilization of single urea, as well as ensure the rice yield and farmers' income, should be deeply investigated to promote wide application of this kind of fertilizer. Based on one-year field experiment and field surveys, four fertilization schemes with different ratios of urea to CRNF were set up, i.e., control (CK), local recommended application amount urea (N1), 100% CRNF (N2), and the combined application of 60% CRNF and 40% urea (N3). Adjusted emergy accounting (EMA), which considers emissions' impacts, and nitrogen use efficiency (NUE) as well as economic indicators were applied to the comparison of environmental sustainability, agronomic indicator and economic benefit of different schemes respectively. The results showed that (1) CRNF utilization raises environment sustainability by 2.82–4.61%; (2) CRNF utilization improves nitrogen use efficiency by 30.65–43.96%; (3) CRNF utilization enhances economic benefit by 5.21–11.44%. Generally, N3 has the best system coordination degree among the three fertilization schemes. Finally, the study suggested popularizing the scheme N3 in this region through adopting appropriate financial and policy support. Meantime, technological innovation, and regulatory supports are needed to accelerate the development of the CRNF industry. • Performance comparison of four N fertilization schemes in rice production. • Controlled release N fertilizer raises environmental sustainability. • Controlled release N fertilizer improves nitrogen use efficiency. • Controlled release N fertilizer enhances economic benefit. • Scheme with part substitute of urea shows the best system coordination degree. [ABSTRACT FROM AUTHOR]

HRPG (Heat recovery power generation) is widely adopted in the cement industry. However, the measure's impacts on the environmental and economic performance of this industry are not completely clear due to the extra resources inputs. To this end, this research implemented an emergy evaluation through considering emissions' impacts, to investigate impacts of HRPG on environmental performance of this industry. Meanwhile, a supplementary economic evaluation was done to explore changes of its economic performance before and after implementing HRPG. One cement enterprise with the two scenarios (Scenario 1 with HRPG vs. Scenario 2 without HRPG), as a case study, was investigated using the presented approach. It is found that (1) HRPG reduces total resources consumption by 1.13%, and raises share of renewable resources by 2.28%; (2) HRPG reduces dependence degree of this enterprise on imported resources and its wealth loss by 1.93% and 1.13% respectively; (3) HRPG enhances wastes recycling rate and energy efficiency by 329.44 times and 6.91% respectively; (4) HRPG enhances emergy yield rate by 0.89%, cuts environmental load rate by 1.77%, and improves environmental sustainability by 2.71%; (5) pollutant emissions' impacts reduce emergy yield rate by 9.48–9.56%, raise environmental rate by 0.02%, and weaken environmental sustainability by 9.50–9.59% (6) HRPG improves economic benefit of this enterprise by 22.24%, which roots in reduced electricity expense. Generally implementation of HRPG achieves energy-saving, emissions reduction and improvement of economic benefit, which well explains why this measure is widely adopted in cement industry. However, this measure is limited to improve environmental performance of this enterprise due to high dependence on nonrenewable resources, and it still has relatively lower energy efficiency than the updated one. Finally this study proposes some targeted suggestions to deal with these issues in the future. Image 1 • Effect of heat recovery power generation (HRPG) on cement production was explored. • HRPG raises energy efficiency and reduces dust emissions' impact. • HRPG has limited contribution to improvement of its environmental performance. • HRPG clearly improves its economic benefit. • Adjustment of its resources structure and update of HRPG should be emphasized. [ABSTRACT FROM AUTHOR]