scholarly journals Green Process for Industrial Waste Transformation into Super-Oxidizing Materials Named Alkali Metal Ferrates (VI)

Materials ◽  
2019 ◽  
Vol 12 (12) ◽  
pp. 1977 ◽  
Author(s):  
Ndue Kanari ◽  
Etleva Ostrosi ◽  
Cécile Diliberto ◽  
Inna Filippova ◽  
Seit Shallari ◽  
...  
Keyword(s):  
Fluidized Bed ◽  
Industrial Effluents ◽  
Transformation Process ◽  
Industrial Wastes ◽  
Iron Sulfate ◽  
Synthesis Process ◽  
Second Step ◽  
Sulfate Heptahydrate ◽  
Complete Control ◽  
Alkali Hydroxides

The investigation presented here features the design of a cleaner and greener chemical process for the conversion of industrial wastes into super-oxidizing materials. The waste of interest is the iron sulfate heptahydrate (FeSO4·7H2O) mainly generated through the sulfate route used for titanium dioxide industrial production. The products of this transformation process are alkali ferrates (A2FeO4, A = Na, K) containing iron in its hexavalent state and considered as powerful oxidants characterized by properties useful for cleaning waters, wastewaters, and industrial effluents. The proposed process includes two steps: (i) The first step consisting of the pre-mixing of two solids (AOH with FeSO4·xH2O) in a rotary reactor allowing the coating of iron sulfate in the alkali hydroxides through solid–solid reactions; and (ii) the second step involves the synthesis of alkali ferrates in a fluidized bed by oxidation of the single solid obtained in the first step in diluted chlorine. The chemical synthesis of alkali ferrates can be carried out within a timeframe of a few minutes. The usage of a fluidized bed enhanced the energy and mass transfer allowing a quasi-complete control of the ferrate synthesis process. The alkali ferrate synthesis process described here possesses many characteristics aligned with the principles of the “green chemistry”.

scholarly journals Parametric Study on the Adjustability of the Syngas Composition by Sorption-Enhanced Gasification in a Dual-Fluidized Bed Pilot Plant

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 399
Author(s):  
Selina Hafner ◽  
Max Schmid ◽  
Günter Scheffknecht
Keyword(s):  
Fluidized Bed ◽  
Ghg Emissions ◽  
Space Velocity ◽  
Synthesis Process ◽  
Wood Pellets ◽  
High Hydrogen ◽  
Syngas Production ◽  
Dual Fluidized Bed ◽  
Bed Material ◽  
Gasification Temperature

Finding a way for mitigating climate change is one of the main challenges of our generation. Sorption-enhanced gasification (SEG) is a process by which syngas as an important intermediate for the synthesis of e.g., dimethyl ether (DME), bio-synthetic natural gas (SNG) and Fischer–Tropsch (FT) products or hydrogen can be produced by using biomass as feedstock. It can, therefore, contribute to a replacement for fossil fuels to reduce greenhouse gas (GHG) emissions. SEG is an indirect gasification process that is operated in a dual-fluidized bed (DFB) reactor. By the use of a CO2-active sorbent as bed material, CO2 that is produced during gasification is directly captured. The resulting enhancement of the water–gas shift reaction enables the production of a syngas with high hydrogen content and adjustable H2/CO/CO2-ratio. Tests were conducted in a 200 kW DFB pilot-scale facility under industrially relevant conditions to analyze the influence of gasification temperature, steam to carbon (S/C) ratio and weight hourly space velocity (WHSV) on the syngas production, using wood pellets as feedstock and limestone as bed material. Results revealed a strong dependency of the syngas composition on the gasification temperature in terms of permanent gases, light hydrocarbons and tars. Also, S/C ratio and WHSV are parameters that can contribute to adjusting the syngas properties in such a way that it is optimized for a specific downstream synthesis process.

Kinetic model for calcium sulfate α-hemihydrate produced hydrothermally from gypsum formed by flue gas desulfurization

2015 ◽  
Vol 48 (3) ◽  
pp. 827-835 ◽  
Author(s):  
Mingliang Tang ◽  
Xuerun Li ◽  
Yusheng Shen ◽  
Xiaodong Shen
Keyword(s):  
Flue Gas ◽  
Calcium Sulfate ◽  
High Performance ◽  
Transformation Process ◽  
Flue Gas Desulfurization ◽  
Synthesis Process ◽  
Stable Phase ◽  
Hydrothermal Conditions ◽  
Simple Method ◽  
Kinetics Of

Modeling of the kinetics of the synthesis process for calcium sulfate α-hemihydrate from gypsum formed by flue gas desulfurization (FGD) is important to produce high-performance products with minimal costs and production cycles under hydrothermal conditions. In this study, a model was established by horizontally translating the obtained crystal size distribution (CSD) to the CSD of the stable phase during the transformation process. A simple method was used to obtain the nucleation and growth rates. A nonlinear optimization algorithm method was employed to determine the kinetic parameters. The model can be successfully used to analyze the transformation kinetics of FGD gypsum to α-hemihydrate in an isothermal batch crystallizer. The results showed that the transformation temperature and stirring speed exhibit a significant influence on the crystal growth and nucleation rates of α-hemihydrate, thus altering the transformation time and CSD of the final products. The characteristics obtained by the proposed model can potentially be used in the production of α-hemihydrate.

Photocatalytic Degradation of Synthetic Sulfur Pollutants in Petroleum Fractions under Different pH and Photocatalyst

2021 ◽  
Vol 02 (01) ◽  
Author(s):  
Mohamad Alif Hakimi Hamdan ◽  
◽  
Nur Hanis Hayati Hairom ◽  
Nurhafisza Zaiton ◽  
Zawati Harun ◽  
...  
Keyword(s):  
Photocatalytic Degradation ◽  
Zno Nanoparticles ◽  
Low Cost ◽  
Industrial Effluents ◽  
Degradation Process ◽  
Vital Role ◽  
Petroleum Fraction ◽  
Precipitation Method ◽  
Synthesis Process ◽  
Petroleum Fractions

Thiophene is one of the sulfur compounds in the petroleum fraction that can be harmful to living things and lead to a critical effect on the ecosystem. Photocatalytic degradation is one of the promising methods in treating wastewater as it can mineralization of pollutants into carbon dioxide and water. Other than that, this method is non-toxic and relatively low cost. The production of hydroxyl radicals playing a vital role in the degradation of organic pollutants. It has been claimed that the usage of zinc oxide (ZnO) nanoparticles could give an excellent degradation process as this photocatalyst have high photosensitivity, low cost and chemically stable. However, the preparation method of ZnO nanoparticles will affect the agglomeration, particle size, shape and morphology of particles and lead to influence the photocatalytic activity in degrading thiophene. Therefore, this study focused on the effectiveness of ZnO nanoparticles in the presence of fibrous nanosilica (KCC-1) and polyethylene glycol (PEG) as the capping agent to degrade synthetic thiophene. ZnO/KCC-1 had been synthesized via the precipitation method and characterized by using Fourier Transform Infrared (FTIR). The chemical bond and nature of the photocatalyst from the FTIR results proved that the synthesis process to produce the ZnO/KCC-1 was succeed. The large surface area of KCC-1 increases the effectiveness of ZnO which is supported by the experimental data. Accordingly, the optimum condition for photocatalytic degradation of thiophene is under pH 7 by using ZnO/KCC-1 as photocatalyst. Hence, it is believed that this research could be implemented to remove the thiophene in petroleum fraction from the actual industrial effluents and this can preserve nature in the future.

Retrofitting 25T/h Pulverized Coal-Fired Boiler Into 35T/h Circulating Fluidized Bed Boiler for Burning Mixture of Coal and Bagasse

2005 ◽  
Author(s):  
Han-Ping Chen ◽  
Xian-Hua Wang ◽  
Shi-Hong Zhang ◽  
De-Chang Liu ◽  
Yu-Hua Lai ◽  
...  
Keyword(s):  
Fluidized Bed ◽  
Circulating Fluidized Bed ◽  
Combustion Efficiency ◽  
Economic Benefits ◽  
Pulverized Coal ◽  
Industrial Wastes ◽  
Pollutant Emission ◽  
Fluidized Bed Combustion ◽  
Circulating Fluidized Bed Boiler ◽  
Combustion Technology

In China, there are a large number of pulverized coal-fired industrial boilers, whose steam capacities are usually relatively small. These boilers can burn only high-grade coal and have low combustion efficiency. Furthermore, the combustion emissions, such as SO2 and NOx, pollute the environment severely. Therefore it is very important and urgent to adopt economically efficient and environmentally friendly technologies to retrofit these boilers. At the same time, there are many industrial wastes, such as bagasse, wood waste, rubbish, petroleum coke and so on, need burning disposal in China. Fluidized bed combustion technology is a kind of clear combustion technology, which has many advantages, such as excellence fuel flexibility, high combustion efficiency, low pollutant emission and good turndown capability etc. So, adopting fluidized bed combustion technology, retrofitting pulverized coal-fired boiler into fluidized bed boiler can realize pure burning various wastes or co-firing with coal, which should have great economic benefits and social benefits. And the application prospect of the method is also extensive. The State Key Laboratory of Coal Combustion has successfully retrofitted a 25t/h pulverized coal-fired boiler into circulating fluidized bed boiler with in-bed tubes and downward exhaust cyclone. The retrofitted boiler can burn mixture of coal and bagasse and the steam capacity reaches 35t/h. This paper presents the retrofitting measures and the operation status of the boiler after retrofitting.

PCR-DGGE analysis of denitrifying bacteria in a metallurgic wastewater treatment process

2002 ◽  
Vol 46 (1-2) ◽  
pp. 333-336 ◽  
Author(s):  
N. Noda ◽  
S. Yoshie ◽  
T. Miyano ◽  
S. Tsuneda ◽  
A. Hirata ◽  
...  
Keyword(s):  
Fluidized Bed ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Precious Metals ◽  
Packed Bed ◽  
Population Diversity ◽  
Operating Conditions ◽  
Industrial Wastes ◽  
Wastewater Treatment Process ◽  
Dgge Analysis ◽  
Gradient Gel Electrophoresis

The wastewater generated from the processes of recovering precious metals from industrial wastes contains high concentrations of acids such as nitric acid and of salts. Biological nitrogen removal from this wastewater was attempted by using a circulating bioreactor system equipped with an anoxic packed bed or an anoxic fluidized bed and an aerobic three-phase fluidized bed. The system was found to effectively remove nitrogen from the diluted wastewater (T-N; 1,000–4,000 mg litre−1). The microbial population structure of activated sludge in an anoxic reactor was analyzed by denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S ribosomal DNA (rDNA) fragments. DGGE analysis under different operating conditions demonstrated the presence of some distinguishable bands in the separation pattern, which were most likely derived from many different species constituting the microbial communities. Furthermore, the population diversity varied in accordance with the nitrate-loading rate, water temperature and reactor condition. Some major DGGE bands were excised, reamplified and directly sequenced. It was revealed that the dominant population in the anoxic reactor were affiliated with the β subclass of the class Proteobacteria.

A Small-Scale Solution for a Big Energy Problem: Renewable Distributed Energy

2009 ◽  
Author(s):  
Renee Comly ◽  
Alex Mathew
Keyword(s):  
Distributed Generation ◽  
Transformation Process ◽  
Environmental Benefits ◽  
Industrial Wastes ◽  
Small Scale ◽  
Energy Problem ◽  
Distributed Energy ◽  
Fuel Gas ◽  
Wide Range ◽  
The Us

A Small-Scale Solution for a Big Energy Problem: Renewable Distributed Energy. Locally generated biomass, industrial and municipal wastes, coal and plastics have a significant part to play in providing a source of reliable and economic energy in the US. The ability to use these materials reliably and cleanly can be addressed with small-scale gasification technology to provide distributed generation. A technology that has improved on the historical success of gasification to provide these elements is TURNW2E™ Gasification. This technology is specifically designed to convert locally available energy resources into a clean fuel gas which is then subsequently used for heat and or power generation. This technology has the ability to operate cleanly and interchangeably using waste materials and /or coal. With the ability to produce power economically from 100 kW to 5 MW it can provide distributed generation at institutions, DOD facilities, and industrial complexes. This creates a reliable and economical energy source for the user, while disposing of wastes in an environmentally sound manner. This replaces landfill use with the energy transformation process of gasification, which provides enormous environmental benefits, including the elimination of carcinogens and reduction of greenhouse gas emissions caused by incineration processes. The use of renewable biomass and wastes provides a sustainable source of electricity that is unrestricted by grid access, providing tremendous potential to reduce US fuel imports. Using this approach, the user can create jobs and power in a sustainable scenario; without sending precious energy dollars overseas, using this process in a distributed manner will help strengthen our nation’s economy, and provide improvements to the quality of life wherever it is installed. By having the ability to use many different feedstocks, the technology can enable the avoidance of landfilling MSW and industrial wastes, including tires; it can use waste wood such as railroad ties, beetle-infested pine, and forestry wastes, farm wastes and natural disaster debris to generate renewable energy for local use or sale to the grid. Materials for processing are varied, and thus, the technology flexibility enables small-scale use in a wide range of installations, a landfill site, transfer station, farm, hospital, manufacturing facility, resort, DOD base, island community, university, and local municipal site. TURNW2E™ Gasification is available at commercial scale and is currently installed at two facilities overseas, with three US facilities planned for ’09. A training and continuing education /R&D facility is underway in the US.

The Usage of Industrialwaste Materials for the Productionof Special Cements and Binders

1994 ◽  
Vol 370 ◽  
Author(s):  
Herbert PÖllmann ◽  
JÜrgen Neubauer ◽  
Hubert Motzet
Keyword(s):  
Fluidized Bed ◽  
Rotary Kiln ◽  
Laboratory Experiments ◽  
Fabrication Process ◽  
Industrial Wastes ◽  
Hydration Process ◽  
Power Station ◽  
Cement Production ◽  
Rapid Hardening ◽  
Calcium Sulfoaluminate

AbstractBy mixing various industrial wastes, as garbage combustion ashes, bottom ashes, fluidized bed ashes, lignite power station ashes, fume purification sulfates and sulfites and lime it is possible to produce cements and binders on the basis of alinite, calcium sulfoaluminate and belite depending on the chemical variety of used wastes.The fabrication process for these cements was studied by laboratory experiments and the different phases and properties were studied in detail. Alinite cement was already produced on a larger scale in a rotary kiln of 10m length. These cements can be used for application purposes in mining mortars, expansive cements, rapid hardening binders and in landfill technologies. The hydration process and workability can be controlled by using various additives. hus industrial wastes can be a secondary resource for special cement production.

scholarly journals Effect of temperature on o-cresol methylation in a fluidized bed of commercial iron-chromium catalyst TZC-3/1

2013 ◽  
Vol 15 (3) ◽  
pp. 100-102 ◽  
Author(s):  
Gabriela Berkowicz ◽  
Witold Żukowski ◽  
Jerzy Baron
Keyword(s):  
Fluidized Bed ◽  
Effect Of Temperature ◽  
Molar Ratio ◽  
Synthesis Process ◽  
Maximum Efficiency ◽  
Chromium Catalyst ◽  
On Line ◽  
Commercial Iron ◽  
By Products ◽  
Iron Chromium

Abstract The paper presents the results of the synthesis of 2,6-dimetyhlphenol (26DMP) from o-cresol. The target compound is an important substrate for polymer chemistry. Due to a large amount of o-cresol which is generated as a by-product, during the synthesis of 2,6-dimethylphenol from phenol, the methylation of o-cresol to 2,6-dimethylphenol should be examined as a separate process. The alkylation of o-cresol was carried out in a fluidized bed of commercial iron-chromium catalyst TZC-3/1. Undesirable decomposition of methyl alcohol on the catalyst generates a number of environmentally dangerous by-products such as methane, carbon dioxide, carbon monoxide. The effect of temperature on the yield of the synthesis was investigated. The synthesis process was monitored on-line in the temperature range 310-380°C, completely covering the maximum efficiency of the process. Online analysis of the process by FTIR spectroscopy gave information about products of both methylation of o-cresol and pyrolysis of methanol. The maximum 85% yield of desired 2,6-dimethylphenol with more than 85% conversion of o-cresol was achieved at 340°C, at 1:6 molar ratio of o-cresol:methanol

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