Biotechnology as an alternative for carbon disulfide treatment in air pollution control

2010 ◽  
Vol 18 (NA) ◽  
pp. 321-332 ◽  
Author(s):  
Naiara Rojo ◽  
Gorka Gallastegi ◽  
Astrid Barona ◽  
Luis Gurtubay ◽  
Gabriel Ibarra-Berastegi ◽  
...  

Biotechnology has emerged as an affordable, effective, and eco-friendly alternative to treat carbon disulfide (CS2) containing waste gases. Carbon disulfide is a chemical of widespread use both in the past and in the present. Its industry demand has dramatically changed over the last two decades and is expected to grow in future in step with those industries involving fibre, mining, rubber products, and the agro-chemical sector. This compound, classified as a hazardous air pollutant about 20 years ago, has been re-appraised, as increasingly restrictive pollution standards are expected to be introduced. An array of physical–chemical technologies for treating CS2 containing air are already in use, but they have a series of drawbacks, such as high energy consumption (incineration, thermal oxidation), the immobilization of the contaminant solely from one phase to another (adsorption), and the generation of secondary by-products that require additional treatment (hydrolysis). Thus, technological research on affordable processing alternatives is of considerable interest for related industries using or producing CS2. The biological technologies whose efficiency is based on the activity of microorganisms to biodegrade air pollutants overcome many of the disadvantages of conventional techniques and are especially useful for the removal of relatively low concentrations of pollutants. In this paper, the main properties, sources, and uses of CS2 are summarized, and alternative biotreatments for CS2 are reviewed. Several applications of the technical and economical feasibility of biofilters and biotrickling filters are shown, although their widespread industrial application still requires further research.

2011 ◽  
Vol 2011 ◽  
pp. 1-9 ◽  
Author(s):  
Bhausaheb L. Pangarkar ◽  
Mukund G. Sane ◽  
Mahendra Guddad

In recent years, the increasing threat to groundwater quality due to human activities has become a matter of great concern. The groundwater quality problems present today are caused by contamination and by overexploitation, or by combination of both, which are faced by many Indian states. Today, reverse osmosis (RO) membranes are the leading technology for desalination of groundwater because of their strong separation capabilities and exhibiting a great potential for treatment of waters worldwide. However, the RO process had some problems due to the formation of polarization films because high pressure operation and by-products which may generate bacteria and fouling. Also, high energy consumption and brine disposal problem is faced in RO process due to the limited recovery of water. These problems may be overcome by other membrane thermal process such as a membrane distillation (MD). This paper addresses the outline of RO and MD process for desalination. RO has developed over the past 40 years and MD is an emerging technology for brackish water desalination and yet is not fully implemented in industry. The MD is the better alternative to RO for desalination theoretically found in the literature.


2017 ◽  
Vol 16 (4) ◽  
pp. 809-819 ◽  
Author(s):  
Gabriel Lazar ◽  
Iulia Carmen Ciobotici Terryn ◽  
Andreea Cocarcea

Atmosphere ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 788
Author(s):  
Rong Feng ◽  
Hongmei Xu ◽  
Zexuan Wang ◽  
Yunxuan Gu ◽  
Zhe Liu ◽  
...  

In the context of the outbreak of coronavirus disease 2019 (COVID-19), strict lockdown policies were implemented to control nonessential human activities in Xi’an, northwest China, which greatly limited the spread of the pandemic and affected air quality. Compared with pre-lockdown, the air quality index and concentrations of PM2.5, PM10, SO2, and CO during the lockdown reduced, but the reductions were not very significant. NO2 levels exhibited the largest decrease (52%) during lockdown, owing to the remarkable decreased motor vehicle emissions. The highest K+ and lowest Ca2+ concentrations in PM2.5 samples could be attributed to the increase in household biomass fuel consumption in suburbs and rural areas around Xi’an and the decrease in human physical activities in Xi’an (e.g., human travel, vehicle emissions, construction activities), respectively, during the lockdown period. Secondary chemical reactions in the atmosphere increased in the lockdown period, as evidenced by the increased O3 level (increased by 160%) and OC/EC ratios in PM2.5 (increased by 26%), compared with pre-lockdown levels. The results, based on a natural experiment in this study, can be used as a reference for studying the formation and source of air pollution in Xi’an and provide evidence for establishing future long-term air pollution control policies.


2019 ◽  
Vol 14 (1) ◽  
Author(s):  
Shiqiang Zhou ◽  
Mingpeng Chen ◽  
Qingjie Lu ◽  
Yumin Zhang ◽  
Jin Zhang ◽  
...  

AbstractFormaldehyde (HCHO) is the main source of indoor air pollutant. HCHO sensors are therefore of paramount importance for timely detection in daily life. However, existing sensors do not meet the stringent performance targets, while deactivation due to sensing detection at room temperature, for example, at extremely low concentration of formaldehyde (especially lower than 0.08 ppm), is a widely unsolved problem. Herein, we present the Ag nanoparticles (Ag NPs) sensitized dispersed In2O3 nanograin via a low-fabrication-cost hydrothermal strategy, where the Ag NPs reduces the apparent activation energy for HCHO transporting into and out of the In2O3 nanoparticles, while low concentrations detection at low working temperature is realized. The pristine In2O3 exhibits a sluggish response (Ra/Rg = 4.14 to 10 ppm) with incomplete recovery to HCHO gas. After Ag functionalization, the 5%Ag-In2O3 sensor shows a dramatically enhanced response (135) with a short response time (102 s) and recovery time (157 s) to 1 ppm HCHO gas at 30 °C, which benefits from the Ag NPs that electronically and chemically sensitize the crystal In2O3 nanograin, greatly enhancing the selectivity and sensitivity.


1993 ◽  
Vol 28 (7) ◽  
pp. 243-250 ◽  
Author(s):  
Y. Suzuki ◽  
S. Miyahara ◽  
K. Takeishi

Gas-permeable film can separate air and water, and at the same time, let oxygen diffuse from the air to the water through the film. An oxygen supply method using this film was investigated for the purpose of reducing energy consumption for wastewater treatment. The oxygen transfer rate was measured for the cases with or without biofilm, which proved the high rate of oxygen transfer in the case with nitrifying biofilm which performed nitrification. When the Gas-permeable film with nitrifying biofilm was applied to the treatment of wastewater, denitrifying biofilm formed on the nitrifying biofilm, and simultaneous nitrification and denitrification occurred, resulting in the high rate of organic matter and T-N removal (7 gTOC/m2/d and 4 gT-N/m2/d, respectively). However, periodic sloughing of the denitrifying biofilm was needed to keep the oxygen transfer rate high. Energy consumption of the process using the film in the form of tubes was estimated to be less than 40% of that of the activated sludge process.


2013 ◽  
Vol 687 ◽  
pp. 255-261 ◽  
Author(s):  
Sandra Cunha ◽  
José Barroso Aguiar ◽  
Victor Ferreira ◽  
António Tadeu

Increasingly in a society with a high growth rate and standards of comfort, the need to minimize the currently high energy consumption by taking advantage of renewable energy sources arises. The mortars with incorporation of phase change materials (PCM) have the ability to regulate the temperature inside buildings, contributing for an increase in the level of thermal comfort and reduction of the use of heating, ventilation and air conditioning (HVAC) equipment, using only the energy supplied by the sun. However, the incorporation of PCM in mortars modifies some of its characteristics. Therefore, the main objective of this study was the characterization of mortars doped with two different phase change materials. Specific properties of different PCM, such as particle size, shape and enthalpy were studied, as well as the properties of the fresh and hardened state of these mortars. Nine different compositions were developed which were initially doped with microcapsules of PCM A and subsequently doped with microcapsules of PCM B. It was possible to observe that the incorporation of phase change materials in mortars causes differences in properties such as compressive strength, flexural strength and shrinkage. After the study of the behaviour of these mortars with the incorporation of two different phase change materials, it was possible to select the composition with a better compromise between its aesthetic appearance, physical and mechanical characteristics.


2013 ◽  
Vol 423-426 ◽  
pp. 667-673 ◽  
Author(s):  
Fan Wen Xin ◽  
Zhi Qiang Xu ◽  
Ya Nan Tu ◽  
Wei Yang ◽  
Xiang Yu Han ◽  
...  

For solving the problems of high energy consumption and high capacity of water-absorption, microwave dehydration technology of lignite was studied in this paper. A self-developed microwave system was used for the experiment on dehydration of lignite from eastern Inner Mongolia. It was proved that the condition of moisture migration was improved and microwave dehydration had a unique mechanism. By analyzing the effects of microwave powers, coal particle sizes, and lignite qualities on drying characteristics, it was found that the moisture decreased when the microwave power increased. it was found that the higher the power was, the faster the moisture decreased; the smaller the particle size was, the faster the moisture decreased; the less the lignite was, the faster the moisture decreased. Through the scanning electron microscope analysis, it was concluded that microwave had no significant effect on the smooth particles, and the fibrous particles and clusters particles tended to be smooth under the effect of microwave. Therefore, the interface of lignite was relatively stable, and not easy to reabsorb water after microwave.


2014 ◽  
Vol 912-914 ◽  
pp. 483-485
Author(s):  
Chen Rong ◽  
David Chan

This paper introduce the basic characteristics of LIFEHOPE Military Fire Blanket, as for independent intellectual property rights new material, we use it is heat insulation, heat preservation to save energy for glass furnace etc. Meanwhile we will explain and put forward the meaning of application of LIFEHOPE military fire Blanket for high energy consumption and heavy pollution industry and enterprise.


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