Sustainable and Clean Utilization of Coal Gangue: Activation and Preparation of Citrate-Soluble Silicon Fertilizer

Abstract Silicon (Si) fertilizer is of great significance to modern agricultural production; the citrate-soluble silicon fertilizer based on coal gangue is one way to protect the environment and meet the agricultural needs of China. In this study, we produced high-efficiency coal-gangue based silicon fertilizer by calcining a mixture of coal gangue, calcium carbonate (CaCO3) and corn stalk powder at high-temperature (i.e., high-temperature activation technology); the effect of temperature and mixing ratio on the available-Si content of activated coal gangue was studied, followed by an analysis of the mechanism of available- Si formation. The results showed that the layered structure of coal gangue was severely damaged above 600 ℃, and the kaolin began to transform into metakaolin and other substances, where the available-Si content was not high (less than 10%). When CaCO3 alone was added, the peak intensity of quartz and muscovite in coal gangue decreased significantly with the increase of CaCO3. However, CaCO3 mainly played a catalytic role in the entire calcination and activation process, forming only a small amount of calcium silicate on the contact surface with coal gangue; however, the available-Si content was still below 12.60%. When corn stalk powder alone was added, the oxides of the corn stalk ash participated in the chemical reaction involving coal gangue, forming nepheline (K(Na, K)3Al4Si4O16) and other silicates, and the available-Si content was significantly higher than that with CaCO3. When coal gangue, CaCO3, and corn stalk powder were mixed and calcined, the available-Si content was as high as 22.97% under the synergistic effect of CaCO3 and corn stalk powder; the concentration of harmful heavy metals was below 0.025 mg/L. The above is in line with the requirements of silicon fertilizer for use in agriculture, thus confirming the preparation of coal gangue-based silicon fertilizer in an efficient manner.

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Preparation of Nanometer Al (OH)3 Powder Using Coal Gangue by Polyacrylamide Dispersant-Carbonization Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.160-162.307 ◽

2010 ◽

Vol 160-162 ◽

pp. 307-313

Author(s):

Zhong Hua Tang

Keyword(s):

High Temperature ◽

Optimum Condition ◽

Aluminum Hydroxide ◽

High Efficiency ◽

Influence Factor ◽

Coal Gangue ◽

The Self ◽

Raw Material ◽

Component Part ◽

Aluminum Component

Polyacrylamide after the molecule degradation is used as dispersant and the coal gangue as the raw material to prepare the nanometer Al (OH)3 powder in this paper. Calcining at high temperature to activate coal gangue and controlling the change of C2S crystal were adopted to prepare the self-pulverized material of coal gangue. When the aluminum component part is distilled with NaAlO2 form from the self-pulverized material of coal gangue by using 8% Na2CO3 solution, the high-pure superfine aluminum hydroxide powder is prepared by using the high efficiency dispersant carbonization method. When the influence factor that the high efficiency dispersant carbonization method prepares high-pure superfine aluminum hydroxide powder has been studied, it has been found that the optimum condition of the high efficiency dispersant carbonization method can prepare the high-pure superfine aluminum hydroxide powder. The average granularity of aluminum hydroxide powder that has been prepared is less than 100 nm and the purity is more than 99.9%, for a new way has been opened up for the high value utilization of coal gangue.

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Mineral phase transformation in coal gangue by high temperature calcination and high-efficiency separation of alumina and silica minerals

Journal of Materials Research and Technology ◽

10.1016/j.jmrt.2021.07.129 ◽

2021 ◽

Author(s):

Mingzhuang Xie ◽

Fengqin Liu ◽

Hongliang Zhao ◽

Chaoyang Ke ◽

Zhiqian Xu

Keyword(s):

Phase Transformation ◽

High Temperature ◽

High Efficiency ◽

Coal Gangue ◽

Mineral Phase ◽

High Temperature Calcination

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Effect of the Temperature on the product yield during the Pyrolysis of Guinea-Corn stalk

10.31224/osf.io/xa3sp ◽

2020 ◽

Author(s):

Adeyemo Kunle Kazeem ◽

adekoya oluwaseun

Keyword(s):

Global Warming ◽

High Temperature ◽

Moisture Content ◽

Pyrolysis Product ◽

Product Yield ◽

Effect Of Temperature ◽

Corn Stalk ◽

Microsoft Excel ◽

Proximate And Ultimate Analysis ◽

The Relationship

This study explain the effect of temperature on the product yield of guinea-corn stalk (Char, tar and Gas). Approximately 0.23kg dried Guinea Corn Stalk (GCS) was introduced into the retort in which the retort was rendered airtight. The retort was placed into the chamber of an electric furnace and the GCS was pyrolysed at a temperature of 400OC at a constant time of 20minutes. This was repeated for temperatures 450,500,550 and 600OC and in each cases, the quantities of char, tar and the bio-gas were determined. Proximate and ultimate analysis were carried out on the sample in other to know the level of moisture content in the sample and also to know if GCS has more contribution to global warming by observing the percentage of the Sulphur and Nitrogen content in the ultimate analysis.Using the sigma plot application as well as the Microsoft excel bar chart to illustrate the relationship between the temperature and the pyrolysis product. This application depict and shown how the increase in temperature affect the product yield (Gas, Tar and Char). The Char yields a percentage of approximately 17% at 400OC and drastically decreased to 27% at 600OC, the tar yields a percentage of approximately 28% at 400OC and increased to 39% at 600OC and also the gas yields a percentage of approximately 17% at 400OC and increased to 34% at 600OC.The result shown that GCS can be pyrolyzed at and high temperature to obtaining more yields of bio-gas.

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The Potential of Photoelectrochemical Carbon Sinks

10.26434/chemrxiv.6231140.v2 ◽

2018 ◽

Author(s):

Matthias May ◽

Kira Rehfeld

Keyword(s):

Global Warming ◽

High Temperature ◽

Greenhouse Gas ◽

Large Scale ◽

High Efficiency ◽

Carbon Sink ◽

Solar Fuels ◽

Negative Emissions ◽

Viable Approach ◽

Low Sensitivity

Greenhouse gas emissions must be cut to limit global warming to 1.5-2C above preindustrial levels. Yet the rate of decarbonisation is currently too low to achieve this. Policy-relevant scenarios therefore rely on the permanent removal of CO2 from the atmosphere. However, none of the envisaged technologies has demonstrated scalability to the decarbonization targets for the year 2050. In this analysis, we show that artificial photosynthesis for CO2 reduction may deliver an efficient large-scale carbon sink. This technology is mainly developed towards solar fuels and its potential for negative emissions has been largely overlooked. With high efficiency and low sensitivity to high temperature and illumination conditions, it could, if developed towards a mature technology, present a viable approach to fill the gap in the negative emissions budget.

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The Potential of Photoelectrochemical Carbon Sinks

10.26434/chemrxiv.6231140 ◽

2018 ◽

Author(s):

Matthias May ◽

Kira Rehfeld

Keyword(s):

Global Warming ◽

High Temperature ◽

Greenhouse Gas ◽

Large Scale ◽

High Efficiency ◽

Carbon Sink ◽

Solar Fuels ◽

Negative Emissions ◽

Viable Approach ◽

Low Sensitivity

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Chemical Modification of Combusted Coal Gangue for U(VI) Adsorption: Towards a Waste Control by Waste Strategy

Sustainability ◽

10.3390/su13158421 ◽

2021 ◽

Vol 13 (15) ◽

pp. 8421

Author(s):

Yuan Gao ◽

Jiandong Huang ◽

Meng Li ◽

Zhongran Dai ◽

Rongli Jiang ◽

...

Keyword(s):

Structural Analysis ◽

High Efficiency ◽

Low Cost ◽

Chemical Activation ◽

Cost Effective ◽

Coal Gangue ◽

Order Kinetic ◽

Practical Applications ◽

Detailed Structural Analysis ◽

Alkaline Conditions

Uranium mining waste causes serious radiation-related health and environmental problems. This has encouraged efforts toward U(VI) removal with low cost and high efficiency. Typical uranium adsorbents, such as polymers, geopolymers, zeolites, and MOFs, and their associated high costs limit their practical applications. In this regard, this work found that the natural combusted coal gangue (CCG) could be a potential precursor of cheap sorbents to eliminate U(VI). The removal efficiency was modulated by chemical activation under acid and alkaline conditions, obtaining HCG (CCG activated with HCl) and KCG (CCG activated with KOH), respectively. The detailed structural analysis uncovered that those natural mineral substances, including quartz and kaolinite, were the main components in CCG and HCG. One of the key findings was that kalsilite formed in KCG under a mild synthetic condition can conspicuous enhance the affinity towards U(VI). The best equilibrium adsorption capacity with KCG was observed to be 140 mg/g under pH 6 within 120 min, following a pseudo-second-order kinetic model. To understand the improved adsorption performance, an adsorption mechanism was proposed by evaluating the pH of uranyl solutions, adsorbent dosage, as well as contact time. Combining with the structural analysis, this revealed that the uranyl adsorption process was mainly governed by chemisorption. This study gave rise to a utilization approach for CCG to obtain cost-effective adsorbents and paved a novel way towards eliminating uranium by a waste control by waste strategy.

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The modification effect of temperature on the relationship between air pollutants and daily incidence of influenza in Ningbo, China

Respiratory Research ◽

10.1186/s12931-021-01744-6 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Rui Zhang ◽

Yujie Meng ◽

Hejia Song ◽

Ran Niu ◽

Yu Wang ◽

...

Keyword(s):

Air Pollution ◽

High Temperature ◽

Air Pollutants ◽

Meteorological Data ◽

Effect Of Temperature ◽

Distributed Lag ◽

Modification Effect ◽

Incidence Risk ◽

The Impact ◽

The Relationship

Abstract Background Although exposure to air pollution has been linked to many health issues, few studies have quantified the modification effect of temperature on the relationship between air pollutants and daily incidence of influenza in Ningbo, China. Methods The data of daily incidence of influenza and the relevant meteorological data and air pollution data in Ningbo from 2014 to 2017 were retrieved. Low, medium and high temperature layers were stratified by the daily mean temperature with 25th and 75th percentiles. The potential modification effect of temperature on the relationship between air pollutants and daily incidence of influenza in Ningbo was investigated through analyzing the effects of air pollutants stratified by temperature stratum using distributed lag non-linear model (DLNM). Stratified analysis by sex and age were also conducted. Results Overall, a 10 μg/m3 increment of O3, PM2.5, PM10 and NO2 could increase the incidence risk of influenza with the cumulative relative risk of 1.028 (95% CI 1.007, 1.050), 1.061 (95% CI 1.004, 1.122), 1.043 (95% CI 1.003, 1.085), and 1.118 (95% CI 1.028, 1.216), respectively. Male and aged 7–17 years were more sensitive to air pollutants. Through the temperature stratification analysis, we found that temperature could modify the impacts of air pollution on daily incidence of influenza with high temperature exacerbating the impact of air pollutants. At high temperature layer, male and the groups aged 0–6 years and 18–64 years were more sensitive to air pollution. Conclusion Temperature modified the relationship between air pollution and daily incidence of influenza and high temperature would exacerbate the effects of air pollutants in Ningbo.

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High-temperature BaTiO3-based ternary dielectric multilayers for energy storage applications with high efficiency

Chemical Engineering Journal ◽

10.1016/j.cej.2021.128760 ◽

2021 ◽

Vol 414 ◽

pp. 128760

Author(s):

Wen-Bo Li ◽

Di Zhou ◽

Wen-Feng Liu ◽

Jin-Zhan Su ◽

Fayaz Hussain ◽

...

Keyword(s):

High Temperature ◽

Energy Storage ◽

High Efficiency ◽

Energy Storage Applications

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Design and Evaluation of the Fresnel-Lens Based Solar Concentrator System Through a Statistical-Algorithmic Approach

Volume 8B: Heat Transfer and Thermal Engineering ◽

10.1115/imece2018-87023 ◽

2018 ◽

Cited By ~ 2

Author(s):

Hassan Qandil ◽

Weihuan Zhao

Keyword(s):

High Temperature ◽

High Efficiency ◽

Incident Light ◽

Thermal Analyses ◽

Solar Spectrum ◽

Chromatic Aberration ◽

Fresnel Lens ◽

Optimum Number ◽

Solar Concentrator ◽

Receiver System

A novel non-imaging Fresnel-lens-based solar concentrator-receiver system has been investigated to achieve high-efficiency photon and heat outputs with minimized effect of chromatic aberrations. Two types of non-imaging Fresnel lenses, a spot-flat lens and a dome-shaped lens, are designed through a statistical algorithm incorporated in MATLAB. The algorithm optimizes the lens design via a statistical ray-tracing methodology of the incident light, considering the chromatic aberration of solar spectrum, the lens-receiver spacing and aperture sizes, and the optimum number of prism grooves. An equal-groove-width of the Poly-methyl-methacrylate (PMMA) prisms is adopted in the model. The main target is to maximize ray intensity on the receiver’s aperture, and therefore, achieve the highest possible heat flux and output concentration temperature. The algorithm outputs prism and system geometries of the Fresnel-lens concentrator. The lenses coupled with solar receivers are simulated by COMSOL Multiphysics. It combines both optical and thermal analyses for the lens and receiver to study the optimum lens structure for high solar flux output. The optimized solar concentrator-receiver system can be applied to various devices which require high temperature inputs, such as concentrated photovoltaics (CPV), high-temperature stirling engine, etc.

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