Papers by Keyword: SO₂

Abstract: The protic ionic liquids (PILs) comprising with N-2-ethylhexylethylenediaminium cation (HEtHex⁺) and bis (trifluoromethanesulfonate) imide anion (TFSA^-) forming [HEtHex][TFSA] which has two amines in the polar group and available to absorbs acid gases such as CO₂ and SO₂. In order to study the CO₂/SO₂ absorption mechanism of [HEtHex][TFSA], the stable configurations of [HEtHex][TFSA]-nCO₂ (n=1, 2, 3, 4) and [HEtHex][TFSA]-nSO₂ (n=1, 2, 4, 6) are investigated using the density functional theory at the M06-2X/6-311G (d, p) level, then the interaction energy, molecular vibration frequency, second-order perturbation energy, electron density and Laplace value are calculated and analysed for the most stable configurations. The results show that N–H^...O type weak or medium hydrogen bonding are mainly formed between [HEtHex][TFSA] and CO₂/SO₂ molecules. The hydrogen bonding interaction is stronger for [HEtHex][TFSA]-nSO₂ comparing with [HEtHex][TFSA]-nCO₂ and increases with increasing the number of CO₂/SO₂ molecules.

Abstract: Lichen or commonly known as symbiotic organism lies between fungi and algae. It is a non vascular simple organism and it is very sensitive to environmental conditions. The research method used was an exploration. It was then continued with the analysis of the pollutant uptake test by a spectrophotometer. To determine the sampling point, the purposive sampling technique was used. The study was divided into 3 main areas based on the environmental differences, namely urban, suburban and forest. There were about 30 trees sticked by corticolous lichens. The pollutant parameters measured were SO2 (sulfur dioxide) and NO2 (nitrogen dioxide). The air quality data were the secondary data such as NO2 and SO2 ambient air that issued by the Environmental Services (DLH) of Surakarta Government Central Java Indonesia. The range of NO2 ambient content in the research locations, namely in the city of Surakarta and the suburban of Jaten Karanganyar was still below the Ambient Air Quality Standards (ABML) issued by the Government, which ranged from 4.29 - 49.72 μg / Nm3.3. The Quality Standard values for ambient NO2 were 316 and μg / Nm3. At the same time, the ambient SO2 values ranged from 0.153 to 36.74 μg / Nm3, still below the threshold of Ambient Air Quality Standards for SO2 issued by the Government on 632 μg / Nm3. The values for SO2 content in the lichen thalli ranged from 0.17 to 4.05 and it was from 0.773 to 4.03 for the NO2 content. The SO2 and NO2 content values in the lichen thalus found in lichens that grow in urban areas are the highest than in urban and forest suburbs. There is a content of pollutant compounds that are identical between thalus lichen and pollutants in the atmosphere (ambient air) so that lichen thalus is able to absorb pollutant compounds in the atmosphere which can be characterized by the morphological characters of thalli that live in urban, suburban and forests. We will be able to publish your paper in electronic form on our web page http://www.scientific.net if the paper format and the margins are correct. Your manuscript will be reduced by approximately 20% by the publisher. Please keep this in mind when designing your figures and tables, etc.

Abstract: SO₂ adsorption by powder activated carbon was investigated in a low temperature drop tube furnace. The effects of C/S mole ratio, adsorption temperature, SO₂, O₂ and H₂O concentration on SO₂ adsorption kinetics were studied. The results show that SO₂ is quickly adsorbed on powder activated carbon in the initial stage and then SO₂ adsorption capacity slow increases with time. The Bangham kinetic model can be used to predict SO₂ adsorption in the low temperature drop tube furnace. SO₂ removal efficiency increases and SO₂ adsorption capacity decreases with C/S mole ratio increasing. SO₂ removal efficiency and SO₂ adsorption capacity both decrease with adsorption temperature increasing. SO₂ removal efficiency decreases and SO₂ adsorption capacity increases with SO₂ inlet concentration increasing. The O₂ and H₂O from flue gas promote SO₂ adsorption by powder activated carbon.

Abstract: SO₂ adsorption by powder activated carbon was investigated in a low temperature drop tube furnace experimental system. The effects of C/S mole ratio and activated carbon circulating ratio on SO₂ adsorption was studied. The results show that SO₂ is quickly adsorbed on the powder activated carbon in the initial stage and the amount of SO₂ adsorbed increases with time. SO₂ removal efficiency increases with increasing C/S mole ratio. Powder activated carbon recycling is important to enhance desulfurization efficiency, reduce the amount of adsorbents and improve the utilization of activated carbon. SO₂ is removed effectively when the C/S mole ratio is 300 and the powder activated carbon circulating ratio is seven.

Abstract: Mg especially in the molten state is well known for its high affinity to O₂. When O₂ content of the atmosphere is larger than 4%, molten Mg will burn! To avoid this, melt protection is necessary. At present mostly SF₆ is used during primary production and processing of Mg and its alloys. Unfortunately SF₆ is a very potent greenhouse gas that is > 23,000 times more effective than CO₂. This also affects life cycle considerations e.g. for the use of Mg alloys in transportation. However, other protective gases like SO₂ or fluorinated hydrocarbons like HFC134a, Novec 612, or AMCover (=HFC134a) have been suggested to replace SF₆. Additionally fluxes mixed from different salts may be used again as well to protect molten Mg. But fluxes and feasible replacements of SF₆ have also disadvantages. Moreover SF₆ and other fluorinated hydrocarbons are under discussion especially in Europe. There is an existing EU legislation that will ban SF₆ from 2018 and there are similar discussions regarding all other fluorinated hydrocarbons. Due to this, new innovative ways have to be found or old methods have to be renewed to allow Mg industries further safe processing of molten magnesium. This contribution will report the state of the art in protecting molten Mg and alternatives to the use of SF₆.

Abstract: With the large-scale usage of coal and gasoline, China has been the most serious SO₂-polluted country in the world. SO₂ can cause respiratory and cardiovascular disease, which does great harm to human health. Therefore, developing an air purifier to absorb trace SO₂ is very necessary. According to the mechanism of SO₂ absorption with the alkaline solution, we developed an air purifier with an purification capacity of 80m³ -100m³ per hour. The purification effect with different gas flow rates, absorbing liquids and initial SO₂ concentration was tested. Test results indicated that the purifier had a very good absorption of trace SO₂ for indoor air. A SO₂ purification model in confined space was established and the purification effect of the purifier was simulated with ANSYS FLUENT 14.0.

Abstract: With the purpose of extending the shelf-life of Kyoho grapes at room temperature (23±1°C), we investigated the effects of two kinds of preservation packaging on Kyoho grapes’ shelf-life: SO₂ controlled release packaging (A bag) and A with 1-MCP packaging (A-1-MCP bag), the grapes naked and packaged with LDPE as the control groups. During the experiment, the headspace concentrations, appearance quality, water loss, stem browning, solidity, TSS and TA were tested and analyzed every two days. The experimental results showed that A bags could form a suitable modified atmosphere packaging (MAP) environment and prohibit the growth of pathogenic bacteria of grapes. After 8 days’ storage, the grapes naked and packaged with ordinary LDPE groups had serious stem browning and rot rate. The stem browning index of the grapes packaged with A bags and A-1-MCP bags were level 1 and level 0. And the rot rate was 3.63% and 1.26%, respectively. The appearance and flavor of the Kyoho grapes had commercial values, the preservation effects were apparent.

Abstract: The revamping project of turning coal-burning boiler into gas-fired boiler for urban heat supply in Tianjin causes high vapor content in flue gas, which has great influences on the day lighting of surrounding buildings. In this paper, CFD software is introduced to simulate the distributions of NO_x, SO₂ and vapor in space after leaving the chimney and their impacts on surrounding buildings with the effect of the atmosphere. Result shows that flue gas discharged from the chimney with the height of 30 m has significant impacts on the surrounding buildings.

Abstract: In this paper, a tube electric furnace is used to process the co-combustion of biomass and crude oil in air atmosphere, the influence of the biomass mass fraction and the temperature on NO and SO₂ emissions are analysed. Research shows that with the increasing addition ratio of biomass to crude oil, the amount of NO in per unit heat reduces. This tendency is more apparent at high temperatures. Compared with crude oil, the NO emission of 20% biomass mass fraction at 1100°C is reduced by 25.8% while 19.02% at 700°C. SO₂ emission in per unit heat decreases with the increasing biomass mass fraction. This tendency is more apparent at low temperatures. Compared with crude oil The generation of SO₂ of 20% biomass mass fraction can reduce 91.5% at 700°C while 36.7% at 1100°C.

Abstract: This Paper introduced the research background and technical features of the simulative experiments in the laboratory with the sorbent of lime solution without lime particles. By means of the effects of various influencing factors on SO₂ removal efficiency were studied carefully. These parameters include gas flow rate (G), inlet SO₂ concentration, liquid-to-gas ratios, the height of the packing and the additive, at the same time menstruating the pH value of the liquid flowing from the tower. To improve desulfurization efficiency of limestone in the wet flue gas desulfurization (WFGD), effect of the hexanedioic acid additive on limestone desulfurization agent were studied. The result shows that this system has advantages of high efficiency, stable, low investment and low circulating cost. The result could give a reference to optimization and will be helpful in selecting desulfurization techniques.