Functionalized Fly Ash Based Alumino-Silicates for Capture of Carbon Dioxide

2011 ◽  
Vol 25 (10) ◽  
pp. 4854-4861 ◽  
Author(s):  
Vivek Kumar ◽  
Nitin Labhsetwar ◽  
Siddharth Meshram ◽  
Sadhana Rayalu
Keyword(s):  
2013 ◽  
Vol 634-638 ◽  
pp. 3688-3695 ◽  
Author(s):  
Yang Xiao ◽  
Shu Gang Li ◽  
Jun Deng ◽  
Xu Wang

In China, as popularizing the technology of fully mechanized top-coal mining and increasing the strength and depth of mining, the gutter-up gob can be formed. But the work of fire preventing and extinguishing for its coal spontaneous combustion is more complexity and difficulty. In this paper, based on geology parameters and mining practice for 93up12 fully mechanized top-coal caving face in Nantun coalmine, the form and character of gutter-up gob are analyzed. According to the hidden danger of high temperature for spontaneous combustion in the gob, we adopt the comprehension technologies of fire extinguishing and preventing which include sealing air-leakage, grouting, and injecting compound gel with fly-ash, foam of retarding oxidation, liquid carbon dioxide, and gas of nitrogen. By putting in practice the pre-controlling technology in gutter-up gob and monitoring data of target gases, it obtains a good effect and ensures the safety in production of the fully-mechanized top-coal caving face.


2013 ◽  
Vol 266 ◽  
pp. 118-125 ◽  
Author(s):  
Ali L. Yaumi ◽  
Ibnelwaleed A. Hussien ◽  
Reyad A. Shawabkeh

2018 ◽  
Vol 35 (8) ◽  
pp. 1642-1649 ◽  
Author(s):  
Yushun Wang ◽  
Tao Du ◽  
Xin Fang ◽  
Da Meng ◽  
Gang Li ◽  
...  
Keyword(s):  

2012 ◽  
Vol 560-561 ◽  
pp. 474-481 ◽  
Author(s):  
Guang Hui Bai ◽  
Tong Song Wang ◽  
Peng Cheng Li ◽  
Lin Lv ◽  
Cai Ling He

It is the first time to determine whether gallium in fly ash was dissolved out with aluminum and study how to separate gallium from aluminum and recover it, tracking and analyzing the gallium in the digested mother liquor from a power plant fly ash extracting Al2O3 by soda-lime sintering process. Carbon dioxide decomposition was performed to the digested mother liquor, exploring the influences on separation of gallium from aluminum from carbon dioxide decomposition time, flow rate, and carbon dioxide decomposition temperature. The results show that when feeding CO2 into the solution, aluminum was firstly dissolved out as the form of Al(OH)3 and then gallium. When carbon dioxide decomposition time, flow velocity and carbon dioxide decomposition temperature were 30min, 100mL/(min • L) and 40°C, respectively, the ratio of aluminum to gallium was from 1028 down to 200. Under this condition, most of aluminum was dissolved out from the solution but gallium was still in it, thus successfully separating gallium from aluminum and leading to a better condition of subsequent process of extracting gallium.


There is no doubt concrete is most useful thing in construction industry but it has a negative impact also, just like a coin has two faces. Raw materials used in manufacturing of concrete affects the environment in one or the another negative way. Like manufacturing of cement produce carbon dioxide whereas the production of aggregates adds dust to the environment. Production of coarse aggregates also impact the geology of the area from they were extracted. A step taken in this direction is the use of waste products along with or in replacement of cement. Many of these materials are already in use, like silica fume, fly ash etc. In this study, plastic coarse aggregates were used in place of natural coarse aggregates. Plastic aggregates were produced by little processing of waste plastic. Plastic is the biggest threat to the environment, and it is affecting the environment rapidly. Some recent studies show that it can be used construction industry due to some of its properties like inert behavior, resistance to degradation etc. Also use of waste plastic can help in reducing plastic waste Various experiments were performed to test the mechanical properties of the concrete with plastic coarse aggregates. Concrete was prepared using plastic coarse aggregates in varying proportions of 0, 2.5, 5, 7.5 and 10%


Energies ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 7101
Author(s):  
Marta Marczak-Grzesik ◽  
Piotr Piersa ◽  
Mateusz Karczewski ◽  
Szymon Szufa ◽  
Hilal Ünyay ◽  
...  

One of the solid waste produced during the combustion of coal are fly ashes. Disposal challenges and environmental consequences are the results of significant process yield and atmospheric emission of fly ashes. The exact chemical composition of FA depends mainly on the type of utilised fuel and combustion conditions. It consists mainly of chemically stable metal oxides, such as Al2O3, Fe2O3, SiO2, CaO, MgO, K2O, Na2O and TiO2, but its toxicity is related to the possible presence of some trace elements, such as As, Hg, Cd, Se and Cr. The chemical and physical properties of fly ash (e.g., particle size distribution, porosity, and surface area) make it suitable as an adsorbent to remove various impurities from process flows such as flue gas stream. Its suitability for capturing mercury from flue gas was experimentally confirmed due to its abundant supply, particle size, bulk density, porosity, chemical composition and low cost. Hence, the use of fly ash as adsorbents and precursors for the production of heavy metal adsorbents is of great practical importance, as it reduces the cost of mercury capture and alleviates the problems associated with the disposal of solid waste. Studies showed that the chemical components present in fly ash additives could stimulate catalytic oxidative capacity, which increases the adsorption of Hg0 oxidation and adsorption of both Hg and CO2. The presented study analysed fly ashes from different zones of the electrostatic precipitator and verified their suitability for removing impurities from flue gases, i.e., mercury and carbon dioxide. The results outlined modified fly ash as having good Hg and CO2 removal capabilities. The adsorption efficiency of Hg reached 92% for Hg and 66% for CO2, while untreated fly ash reached 67% for Hg and 59% for CO2.


2015 ◽  
Vol 802 ◽  
pp. 118-123 ◽  
Author(s):  
John Wilmer Bautista ◽  
John Benedict Crockett ◽  
Beatrice Ann Liu ◽  
Timothy John Obra ◽  
Cheryl Lyne Roxas

Drying shrinkage in mortar produces cracks and micro-cracks which affect the durability of a structure. The effects of seawater as a substitute to freshwater and fly ash as a partial replacement for cement were investigated in this study in order to address the predicted water shortage by 2025 and the increasing carbon footprint from carbon dioxide emissions worldwide. Moreover, these materials are also more economical alternatives to freshwater and cement. Rectangular prism specimens with varying fly ash content (10%, 15%, 20%, 25%, and 30%) were cast to measure the drying shrinkage in mortar while 50-mm cube mortar specimens were prepared to determine the compressive strength. This study investigated whether the addition of fly ash and seawater reduced the drying shrinkage of mortar. From the results, it was found that mortar specimens with 20% fly ash replacement achieved the highest early and late strengths. Partial substitution of fly ash would result to shrinkage in mortar while substitution of seawater to freshwater counteracts the effects of fly ash, thus producing less shrinkage. Fly ash content between 20%-25% combined with seawater produces the least shrinkage value without compromising the minimum required compressive strength.


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