With the increase in the depth of coal mining, the problem of coal spontaneous combustion due to air leakage in the coal mine roadways is becoming increasingly serious. However, traditional cement mortar spray coatings are prone to cracking and poor flexibility, and polyurethane type spray coatings are not flame retardant, they are unable to meet the spraying needs. This paper proposes the preparation of a cement-based flexible spray coating for flame retardant (CFSCF) by modifying the cement-based material with the addition of fly ash, cellulose and emulsion material. The initial dosage ranges of fly ash, cellulose and emulsion material were studied. The effects of different dosages of fly ash, cellulose and emulsion material on the 7-day tensile strength, 14-day tensile strength and 28-day tensile strength were studied, and the optimum ratio of CFSCF was determined by the response surface methodology. The tensile mechanical properties, micromorphology and flame retardant properties of CFSCF with the optimum ratio were studied. The results showed that: the tensile strength of CFSCF reached the maximum at 28 days of maintenance period, 2.55 MPa; the maximum elongation at break was 52.62% at 14 days; the tensile toughness was up to 833.05KJ m−3; when the material was pulled, the two walls of the crack would bond to each other, reflecting the excellent flexibility; the alcohol lamp burning test results showed that there is flame burning time of 0 s, the material leaves the flame extinguished, has good flame retardant properties.

A growing number of cartridge dust collectors are used in the underground mining, but the underground wetting state have a grave impact on their performance. In order to study the influence of filter cartridge (FC) wetted before filtration and during filtration on the dust collector, a test system was built. The results showed that the pressure drop (PD) of wetted mechanical filter cartridge (MFC) returned to initial PD after 24 h, and coated filter cartridge (CFC) only need 12 h. The PD of pre-wetted FC rose rapidly while filtrated dusty air. The residual pressure drop (RPD) of pre-wetted FC was high, which heavily reduced the service life of FC. If FC was wetting during filtration of dusty airflow, the PD were minimum when the spray rate was 450 mL/ h, and the PD of MFC was higher than that of CFC.

Arenediazonium salts represent an important class of aromatic organic compounds widely used as building blocks in academia and industry. Due to the high energy associated with the diazonium group, many of these salts are reported as thermally unstable and/or unsafe to work with. However, most of the tetrafluoroborate arenediazonium salts are fairly stable to handle at room temperature both in solution and when dry. Nevertheless, some of these salts, especially those containing heteroatoms in the aromatic moiety, are problematic for their synthesis, and some are indeed highly unstable. To bring some light on this controversial subject, the thermal stability and potential hazards of the 58 most common arenediazonium tetrafluoroborate salts used by us over the last two decades were evaluated under careful conditions. These results are expected to guide conscious decisions on the use and handling of arenediazonium tetrafluoroborates in organic synthesis.

Phosphorus and nitrogen pollutions from agricultural non-point source put heavy burden on water environment. Total nitrogen (TN), total phosphorus (TP) and ammonia nitrogen (NH3-N) are important pollutants in the study of agricultural non-point source pollution. This study presents a technical system that accurately calculated the coefficient of pollutants (TN, NH3-N and TP) entering water to grasp the situation of agricultural non-point source pollution. The system used for coefficient calculation is based on a main framework of driving factor-transmission factor-infiltration factor-interception factor, incorporating critical impacting factors including rainfall, topography, surface runoff, underground runoff, and interception factors. The coefficient was calculated by selecting typical units and extrapolated to the main stream area of the upper reaches of the Yellow River. Our study provides reference and practical basis for the development and application of coefficient model. It provides enlightenment for the calculation of agricultural non-point source pollutants.

In modern buildings, false ceilings are widely used for building services systems and aesthetic purposes, but they also pose challenges in terms of fire safety. A fire accident typically results from the failure of multiple safety measures or components. In many fire accidents, fire and smoke reached the false ceiling and kept spreading in the interstitial space without any detection. This study first generates a numerical database of false ceiling fire scenarios by varying the room dimensions, false-ceiling leakage area, fire size and locations. Then, a smart model based on machine learning to predict the fire smoke motion below and above the false ceiling is developed. The trained model is capable to predict the activation time of fire detectors and sprinklers for any given false ceiling design and fire scenario. This methodology enables a designer to generate multiple fire scenarios and determine the available safe egress time (ASET) for performance-based fire engineering designs especially in terms of fire detection time. In case of a real fire, with the data feed from the fire sensor network, the trained machine learning model can further predict the critical building fire events with the false ceiling, such as multi-compartment fires, smoke in the evacuation path, and structural failures. This work proposes a smart framework for improving the building fire safety design of false ceilings and the sensor-driven fire forecast to support firefighting.It enhances the emergency response processes by enabling dynamic risk assessment through prediction of critical events.

The present study proposes and investigates a novel solar, geothermal and biomass based multi-generation system producing multiple outputs to generate power, hydrogen, heating, cooling, and fresh water. Parabolic trough solar collectors, a two stages Rankine cycle, two organic Rankine cycles, two absorption cooling systems, a gas turbine system, a once-through (OT) multi stage flash (MSF) desalination unit, a geothermal unit, a heat pump, an electrolyser and a thermal energy storage are used as sub-systems. The novelty of the system is to focus on novel sub-system design pattern for the proposed multi-generation system by using multiple energy inputs as there is a gap about those studies in the literature. The overall system performance is evaluated from energetic, exergetic, exergo-economic, environmental (4E) and sustainability points of view by using the EES software package. The total installed power and hydrogen mass flow rates are 7.76 MW and 3.52 kg/h, respectively. The energy and exergy efficiency values of the overall system are found to be 65.55% and 27.09%. Fresh water flow rate is calculated to be 6.16 kg/s with 10 stages. The overall unit product cost is determined to be 21,79 $/GJ and the overall social ecologic factor is calculated to be 1.37.

The urgent need to address greenhouse gas (GHG) emissions, particularly in relation to climate change, is driving the demand for new sustainable renewable fuels. This demand is promoting the expansion of de-carbonization efforts, which hold tremendous potential as a renewable energy source. One area of focus is the production of hydrogen (H2), which has long been a popular subject of discussion. Currently, large quantities of H2 are generated using conventional fossil fuels. However, the finite nature of these resources has compelled the global community to explore alternative, more environmentally friendly options like biomass. Generating H2 on a large scale from various biomasses presents a complex challenge. Researchers have identified thermochemical (TC) and biological (BL) processes as the primary methods for converting biomass into H2, although other techniques exist as well. Commercializing H2 as a fuel presents significant technological, financial, and environmental hurdles. Nevertheless, nanomaterials (NMs) have shown promise in overcoming some of the obstacles associated with H2 production. This review focuses on the use of NMs in TC and BL processes for H2 generation. Additionally, the paper provides a brief overview of the methods and financial considerations involved in enhancing biomass-based H2 production. Studies indicate that the production of bio-H2 is relatively expensive. Direct bio-photolysis costs range from $2.13 kg-1 to $7.24 kg-1, indirect bio-photolysis costs range from $1.42 kg-1 to $7.54 kg-1, fermentation costs range from $7.54 kg-1 to $7.61 kg-1, biomass pyrolysis costs range from $1.77 kg-1 to $2.05 kg-1, and gasification costs $1.42 kg-1. The paper also explores various challenges related to biomass conversion and utilization for H2 production, aiming to better understand the feasibility of a biomass-based H2 economy.

In recent years, biodiesel has attracted increasing interest as a substitute for fossil fuels. However, the cost of producing biodiesel is far greater than that of fossil fuels. As a means of reducing the cost of production, biodiesel has been produced from different kinds of feedstock based on local availability. Howbeit, the quality and efficiency of the transesterification process have been limited by the feedstock quality. It has been documented that the quality of biodiesel produced depends on the fatty acid compositions and the physicochemical properties of the oil feedstock. Moreover, the use of heterogeneous catalysts in the trans-esterification process has been preferred due to their reusability, and ease of product separation. Different kinds of solid-based catalysts influence the yield of the biodiesel produced, this was based on the distinct basicity and textural properties of the catalyst used. Hence, researchers have sought to improve the trans-esterification reaction by altering the basicity, surface area, and porosity of the catalyst. In addition, trans-esterification process parameters such as methanol: oil ratio, catalyst loadings, reaction time, reaction temperature, stirring rate, and ultrasonic irradiation influences the catalytic transesterification reaction. Therefore, this review considers the effect of oil feedstock properties, the heterogeneous catalytic properties, and transesterification process parameters as it affects the transesterification process. It also considers the mechanism of the transesterification reaction and discusses the challenges and areas that require improvement.

As an emerging micro-pollutant, p-arsanilic acid (p-ASA) exist widely in the environment, and it can form highly toxic arsenate and arsenite during the migration and transformation process, which greatly increases the risk of arsenic pollution in the ecosystem. Additionally, three-dimensional (3D) porous block materials have the advantage of stronger adsorption performance, faster adsorption rate and easy recovery, showing broad application prospects in water pollution control. Hence, the aminozed collagen fibers foam (ACFF) with 3D porous block structure was synthesized. The maximum adsorption capacity of ACFF for p-ASA was 476.19 mg·g−1 due to the rich honeycomb porous structure and the synergistic effect of electrostatic attraction, hydrogen bonding effect and amphiphilicity. Moreover, ACFF is not only easy to recycle, but also has good elastic recovery and regeneration performance. The pore size of ACFF was concentrated in the range of 25–5000 nm, and the porosity was 71.66%. ACFF may be an adsorbent with great potential for the removal of organoarsenic contaminants in water.

Flame geometry is a fundamental problem in assessing the thermal hazard during the transport process of hazardous chemicals, while the existing literature mainly focuses on stationary fires, with little understanding of flame behavior in moving fires. The objective of this study is to address the air entrainment mechanism of moving fires and derive the characterization models of relevant flame parameters. Dimensional analysis was used to determine the main factors influencing flame geometry in moving fires. A 1:10 scale burning car was then designed, and a series of moving model experiments were conducted to investigate the flame geometry. The results show that the flame height decreases monotonically with the increasing moving velocity, while the flame tilt angle gradually increases to a constant value. The variation of the flame width and the flame length includes three regimes: the decreasing regime, the transition regime, and the increasing regime. The evolution mechanism of the flame geometry can be attributed to the competition between the buoyancy and the inertia forces, which forms the bilateral, unilateral, and enhanced unilateral entrainment modes. Dimensionless correlations are provided to describe the flame geometries. Comparison between previous wind-blown flame models and the experimental data suggests that considerable error exists when studying moving fires by using wind tunnel experiments, despite their applicability to relevant aerodynamics studies.

This study explores the differences between two novel cogeneration systems with different connection modes. These two systems are the series and parallel systems composed of the Brayton cycle, the organic flash cycle, and the organic Rankine cycle, respectively, which both recover flue gas waste heat and LNG cold energy. First, the equipment and overall system performance of the series system and the parallel system are compared from three aspects of thermodynamics, economy, and exergoenvironment to evaluate the basic performance of the two systems under initial conditions. Next, the performance variations of both systems are assessed by varying the compressor outlet pressure, flash pressure, R14 mass flow rate, and heat source temperature. Finally, the Multi-Objective Cuckoo Search algorithm is used to optimize the systems for two and three objectives, taking the exergy efficiency, payback period and product unit exergoenvironmental impact as objective functions. The final results indicate that the three-objective optimized parallel system has the best performance, the exergy efficiency, payback period, and product unit exergoenvironmental impact of that is 62.25%, 1.389 years, and 7.799×10-3 mpt/kJ, respectively. By comparing the performance differences between the series system and the parallel system, this study provides application ideas for engineering requirements.

Persulfate-based advanced oxidation processes (AOPs) have attracted considerable attention in the treatment of organic wastewater with high performance and long lifetime. The construction of efficient, environmentally-friend, and stable nanocatalysts has been recognized as a promising approach to activate persulfate. Herein, magnetic CeO2-MnFe2O4 nanomaterials fabricated via a simple sol-gel method were used for the first time to enhanced activate persulfate (PS) for the removal of the organic pollutant enrofloxacin (ENR). It was demonstrated that 97.2% of ENR (10 mg L−1) was efficiently degraded. 63.3% of TOC decreased within 35 min under a neutral solution (pH 6.81) in the PS+CeO2-0.2MnFe2O4 system using a catalyst dosage of 0.25 g L−1 and 0.18 mM PS. The magnetic CeO2-MnFe2O4 nanostructures maintained excellent recovery as well as recyclability ENR removal efficiency was 90% after recycling five times. EPR and quenching tests indicated that sulfate radicals (SO4•−) and hydroxyl radicals (•OH) significantly contributed to ENR removal. XPS analysis showed that the synergistic redox cycles of Ce3+/Ce4+, Mn2+/Mn3+, and Fe2+/Fe3+ are essential to activate PS for ENR degradation. DFT calculations also revealed that PS molecules preferred to adsorb to and dissociate on CeO2-MnFe2O4 surfaces rather than just CeO2 and MnFe2O4 surfaces. CeO2 plays a dual role in the charge transfer from CeO2-MnFe2O4 to PS molecules, i.e., both electron storage and donor. This work also provides a new interpretation to explain the activation mechanism of PS. The developed CeO2-MnFe2O4 nanostructures with rapid removal efficiency, high degradation efficiency and good recyclability may provide potential guidance for the design of polymetallic oxide nanocatalysts in PS-based AOPs.

Safety instrumented systems (SISs) are installed on process plants to protect against undesired events like e.g., gas leakage and overpressure. A SIS has reliability requirements that are determined during design, and conformance to these requirements should be verified during operation. It is therefore important that all SIS failures are recorded and classified according to their impact on the SIS reliability. Failures of SIS equipment classified as dangerous undetected are of particular interest because they are dormant (undetected) and will prevent the execution of the safety function (dangerous). Analysis of the failure mode and detection method is essential when deciding if a failure is dangerous and undetected. Such information is often provided as unstructured text in notifications registered into the maintenance management system. Therefore, the work of classifying failures requires considerable manual effort in reading and analyzing the texts. Approaches within natural language processing, like technical language processing, have the potential to be deployed more actively for this purpose. However, successful adoption relies on groundwork where classification rules are derived from international standards and commonly agreed industry practice. This paper presents a semi-automated process that incorporates classification rules and gives examples that indicate some of the capabilities of technical language processing for failure classification. The paper also elaborates on how the work relates to Industry 4.0 in creating digital representations to monitor the performance of safety instrumented systems. This work has been carried out as part of the APOS project (Automated process for follow-up of safety instrumented systems). The APOS project has developed knowledge and specifications that simplify and automate the design and operation of safety equipment and investigated how the failure classification process can be made more efficient.

The cost-effective desalination of shale-gas produced water (PW) has long been an industrial research hotspot. Flow-electrode capacitive deionisation (FCDI), a recently developed electrochemical desalination technology, may be a novel option for PW disposal because of its attractive advantages. However, reports on the desalination test of actual high-salinity industrial wastewater by FCDI are lacking. In this study, a laboratory-scale FCDI device with an online monitoring system was used to desalinate shale-gas PW. FCDI achieved relatively stable desalination efficiency for pretreated PW with a salinity of 2.65 % and reached an energy-normalised salt removal of 0.479 mg/J. The flow electrode chemically activated by KOH increased the FCDI average desalination rate by 98.5 % for the pretreated saline PW. Electrochemical impedance spectroscopy analysis revealed that the majority of fouling accumulated on the anion-exchange membrane (AEM) side. Residual pollutants were adsorbed by the flow electrode in the AEM chamber, which destroyed the optimal ion-transport path and electric double-layer structure. Results showed that FCDI was more suitable for PW’s reverse-osmosis (RO) permeate desalination to form an RO–FCDI hybrid. This study provided a practical experimental case on the electrochemical desalination of saline PW by FCDI.

In a fire environment, liquid storage tanks are prone to integral cracking and eventually boiling liquid expanding vapor explosion (BLEVE), which a fireball, generates overpressure and ejected fragments with great impact on the safety of the tank area. Hence, it is important to reveal the influencing factors of the liquid storage tank failure process and the conditions that trigger integral cracking failure for the flammable liquid tank explosion accident prevention. This paper is aimed at the failure problem of metal storage tanks exposed to high temperature for a long time, through the fire experiment of small liquid tanks, taking the filling rate of tanks itself and the fire engulfment area as variables, the failure mechanism of tanks fire environment was explored from the aspects of pressure response, temperature response, failure form and tank deformation characteristics. A criterion was proposed to determine whether BLEVE will occur, which is based on the comprehensive analysis of the influence of tank internal pressure and high temperature damage of the material.

Hydrogen as a clean fuel can simultaneously respond to the challenges of energy shortage and environmental issues, provided that it is produced in a clean and cheap way. In this research, a hydrogen production system based on the combination of a solid oxide electrolyzer with a gasifier and a hydrogen separation membrane has been studied from a techno-economic outlook. In order to achieve a proper approximation of the levelized cost of hydrogen (LCOH), an elaborated economic analysis has been performed considering all aspects, where the life of the hydrogen separation membrane (HSM) and the solid oxide electrolyzer (SOE) has been taken into account. Finally, the minimization of the levelized cost of hydrogen and the levelized carbon dioxide emission (LCE) was carried out through multi-objective optimization. The cost of selling hydrogen was determined according to the various payback times. According to the conducted optimization, it is possible to obtain the minimum levelized cost of hydrogen of 3.63 $/kg. This condition leads to the levelized emission of 10.17 kg CO2/kg H2. Also, the system has the ability to bear levelized CO2 emissions up to 2.92 kg CO2/kg H2, so that the levelized cost of H2 production is 6.45 $/kg. In the four optimal conditions obtained from the optimization, considering the payback time of 5 years, the cost of selling the produced H2 can be 3.64 $/kg, 6.45 $/kg, 5.98 $/kg, and 5.29 $/kg.

Diesel particulate filter (DPF) is one of the effective technologies for controlling vehicle particulate matter (PM) emissions. In this research, a hybrid multi-objective optimization approach of FGRA-RSM-MOPSO was developed for DPF, with optimization objectives including maximum initial filtration efficiency and minimum pressure drop. Decision variables include diameter, length, wall thickness, porosity, and pore diameter. Firstly, a computational fluid dynamics (CFD) model for DPF was established, and sensitivity analysis of DPF structural parameters was conducted through fuzzy grey relational analysis (FGRA) to screen out key factors affecting DPF trap performance. Then, response surface methodology (RSM) was used to establish the mathematical relationship between key structural parameters, initial filtration efficiency, and pressure drop. Finally, multi-objective particle swarm optimization (MOPSO) is used to optimize the target and select the optimal solution from the Pareto front. Compared with the original DPF, the optimized DPF under standard operating conditions increased the initial filtration efficiency by 46.85% and reduced the pressure drop by 34.88%. The optimization effect is more pronounced under high load conditions.

Proteins from agricultural and livestock wastes are rapidly emerging as potential alternatives for non-biodegradable PVA sizes due to their excellent film-forming ability, amphiphilic, biodegradable, low cost and low carbon footprint. However, brittleness of protein-based films that failed to be directly used as textile sizing to protect yarns during high-speed weaving limits their practical applications. Different methodologies to modify protein-based materials to impart excellent properties are highly desired to be better used in textile sizing. Therefore, in this review, recent advances in the various modification methods of proteins and its applications in textile sizing have been focused. The categories, structure, methodology and characterization of modified-protein are fully covered. This review provides an overview of recent research advances on different protein-based textile sizing agents and promotes the development of a new generation of multifunctional bio-based materials from biological renewable resources and sustainability of the textile industry.

Hydrothermal dechlorination of polyvinyl chloride (PVC) is primarily performed in stainless-steel reactors prone to chlorine-induced pitting corrosion, contaminating the reaction media with Fe2+, Ni2+, and Cr2+ possibly triggering shifts in the degradation chemistry. This study investigated the single and synergistic effects of Fe2+ and Ni2+ on urea-assisted hydrothermal dechlorination of PVC under mild conditions. Significant improvement in dechlorination degree was observed at 210 °C when 5 mmol/L Fe2+ or 10 mmol/L Ni2+ was added. Furthermore, positive interaction between the cations was confirmed when the simultaneous use of 1 mmol/L Fe2+ and 0.25 mmol/L Ni2+ achieved the same catalytic performance. The presence of these ions prevented adhesive contact of PVC particles, thus limiting the mass-transfer resistance and autocatalytic effect. The experimental design revealed that dechlorination and its improvement were temperature-dependent (p < 0.0001). Ni2+ and Fe2+ exerted quadratic and linear effects, respectively, on dechlorination. The highest catalytic activity occurred in the temperature range of 217.5–222.5 °C. The results show that total concentrations of as low as 1.08 mmol/L accelerated dechlorination, indicating the inappropriateness of using steel reactors for determining intrinsic PVC degradation chemistry. However, Fe–Ni composites have the potential to be used as catalysts.

The suppression effects of melamine polyphosphate, titanium dioxide and melamine cyanurate powders on titanium hydride dust explosions were studied using a 1.2 L standard Hartmann tube system, a 20-L spherical vessel testing system, a simultaneous thermal analyzer and a field emission scanning electron microscope. The experimental results showed that the three solid suppressants could effectively decrease the explosion parameters such as flame luminescence intensity, flame propagation velocity and maximum explosion pressure, et al. Because of the different suppression characteristics of the suppressants, their suppression effects on the particles combustion temperatures were significantly different. To completely suppress the dust explosion of titanium hydride, the inerting ratio of the melamine polyphosphate powders was the smallest when compared with those of the titanium dioxide and melamine cyanurate powders. In addition, the field emission scanning electron microscope was used to analyze the residues of a dust explosion. The testing results showed that the thermal decomposition residues of melamine polyphosphate powders were coating on the surface of the unburned titanium hydride particles to make them lose reactivity, that was why the suppression effect of melamine polyphosphate powders was the most effective when compared with titanium dioxide and melamine cyanurate powders.