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11.
Generation and Quantification of Hazardous Dusts from Coal Mining in the Indian Context 总被引:1,自引:0,他引:1
Ghose MK 《Environmental monitoring and assessment》2007,130(1-3):35-45
The increasing trend of opencast coal mining in India tends to release huge amounts of dust. But there is no well-defined
method of estimating dust emission due to different coal mining activities. This paper examines the sources of dust emission
due to coal mining activities, and focuses on the quantification of dust emission with the development and use of emission
factors. Because of their site-specific nature, emission factors developed for one site may not give the correct results for
another site. In the present investigation, prediction equations are utilized for the development of emission factors. For
the applications of this concept, one large opencast coal project of Bharat Coking Coal Ltd. (BCCL) was investigated, and
the total amount of dust emitted due to different mining activities was calculated by the utilization of emission factor data,
which was estimated to be 9368.2 kg/day. This paper also focuses on the significance of this study in the field of environmental
protection and likely impacts of such study. The paper concludes that once the amount of dust generation is estimated, the
impact on air quality can be assessed appropriately and a proper air-pollution control strategy can be developed. 相似文献
12.
Georgios K. Sylaios Vassilios A. Tsihrintzis 《Environmental Modeling and Assessment》2009,14(1):59-72
The nutrient dynamics of the Strymonikos and Ierissos Gulfs, two semienclosed coastal water bodies, are studied using a simple
steady-state budget model, according to the Land–Ocean Interaction in the Coastal Zone modeling guidelines. Strymon river
plume dynamics prevailed in the area of the Inner and Outer Srymonikos Gulfs, comprising two layers, while the Ierissos Gulf
was defined as a one-box system. Seasonal and mean annual model input data for river discharge, precipitation, evaporation,
and concentrations of salt, phosphorus, and nitrogen were obtained during four field campaigns. Results from the nitrogen
and phosphorus cycling revealed the importance of river discharge in the horizontal and vertical transport of these substances
within the system. Furthermore, it occurred that the major biogeochemical transformation of nitrogen and phosphorus takes
place in the immediate nearshore zone (Inner Strymonikos Gulf), while the outer system sustains its nutrient dependence on
oceanic exchanges. Therefore, under the summer low flow conditions, the river-influenced inner system acts as a net source
of nitrogen and phosphorus, while under increased Strymon River discharge, phosphorus is transferred to the biological material
(and the sediments), and the system moves to an autotrophic state. The outer system showed an opposite behavior being autotrophic
throughout the year and heterotrophic in February. The Ierissos Gulf, a system not directly influenced by significant river
discharge, experienced a seasonally independent behavior with net heterotrophic and denitrification processes prevailing.
Model scenarios demonstrated that phosphate concentration increases, even under low river flow conditions and stimulates primary
production in excess of respiration, resulting in nitrogen fixation prevalence in the Inner Strymonikos Gulf. 相似文献
13.
确定卫生防护距离应注意的问题 总被引:10,自引:0,他引:10
饶示欣 《石油化工环境保护》1999,(4):42-43
本文总结了石化行业卫生防护距离标准编制和环境影响评价工作中的经验,对确定卫生防护距离时应注意的一些问题进行了探讨,并提出了一种新的确定石化装置废气无组织排放量的方法。 相似文献
14.
Sana Sadaf Haq Nawaz Bhatti Muhammad Arif Misbah Amin Farva Nazar 《Chemistry and Ecology》2013,29(3):252-264
This paper reports the application of Box-Behnken experimental design to illustrate the adsorption of direct dyes (Indosol Black NF and Indosol Orange RSN) using polyethyleneimine (PEI)-treated peanut husk biomass. The effect of three independent variables (initial dyes concentration, biosorbent dose and pH) was investigated during the study. Maximum biosorption capacity (141 and 98.2 mg/g) of PEI-pretreated biomass was achieved with 200 mg/L initial dye concentration and 0.05 g/50 mL biomass dose for Indosol Black NF and Indosol Orange RSN, respectively. Acidic pH was found to be favourable for maximum dyes removal. Characterisation of biosorbent was carried out through Fourier transform-infrared spectroscopy (FT-IR), scanning electron microscopy, thermogravimetric analysis (TGA) and point of zero charge determination. FT-IR analyses confirmed the involvement of carboxylic and carbonyl groups. The desorption study was also conducted to check out the possibility of regeneration of dyes and adsorbent and it was found that 51.58 and 76.6% of Indosol Black NF and Indosol Orange RSN, respectively, can be desorbed from the loaded biosorbent by using 1 M NaOH solution. The results indicated that PEI-treated peanut husk biomass can be used as an efficient biosorbent for the removal of Indosol Black NF and Indosol Orange RSN dyes from aqueous solutions. 相似文献
15.
16.
Yu Mo Lei Zhao Zhonghui Wang Chia-Lung Chen Giin-Yu Amy Tan Jing-Yuan Wang 《Waste management (New York, N.Y.)》2014,34(4):763-769
A work applied response surface methodology coupled with Box–Behnken design (RSM-BBD) has been developed to enhance styrene recovery from waste polystyrene (WPS) through pyrolysis. The relationship between styrene yield and three selected operating parameters (i.e., temperature, heating rate, and carrier gas flow rate) was investigated. A second order polynomial equation was successfully built to describe the process and predict styrene yield under the study conditions. The factors identified as statistically significant to styrene production were: temperature, with a quadratic effect; heating rate, with a linear effect; carrier gas flow rate, with a quadratic effect; interaction between temperature and carrier gas flow rate; and interaction between heating rate and carrier gas flow rate. The optimum conditions for the current system were determined to be at a temperature range of 470–505 °C, a heating rate of 40 °C/min, and a carrier gas flow rate range of 115–140 mL/min. Under such conditions, 64.52% WPS was recovered as styrene, which was 12% more than the highest reported yield for reactors of similar size. It is concluded that RSM-BBD is an effective approach for yield optimization of styrene recovery from WPS pyrolysis. 相似文献
17.
James N. Kremer Jamie M.P. Vaudrey Deanna L. Bergondo Chris Kincaid Mark J. Brush 《Ecological modelling》2010,221(7):1080-314
A computational scheme has been developed and tested to simulate property exchange by advection and dispersion in estuaries at time and space scales that are well suited to ecological and management simulations, but are coarse relative to the demands of physical hydrodynamic models. An implementation of the Regional Ocean Model System (ROMS) for the Providence River and Narragansett Bay (RI, USA) was used to determine property exchanges between the spatial elements of an ecological box model. The basis for the method is the statistical tabulation of numerical dye experiments done with the full ROMS physical model. The ROMS model domain was subdivided into fifteen coarse boxes, each with two vertical layers, defining 30 elements that were used for the box model simulations. Dye concentrations were set to arbitrary initial concentrations for all ROMS grids in the large elements, and the ROMS model was run for 24 h. The final distribution of the dye among the elements was used as a tracer for property exchange over that day and was used to develop an exchange matrix. Box model predictions of salinity over 77 days in each element compared favorably with ROMS simulated salinity averaged over the same spatial elements, although the disparity was greater in areas where large river inflows caused strong gradients in ROMS within elements assumed to be homogeneous in the box model. The 77-day simulation included periods of high and low river flow. Despite the large size of the spatial elements, dispersion artifacts were small, much less than the modeled daily exchanges. While others have taken a similar approach, we found a number of theoretical and practical considerations deserved careful attention for this approach to perform satisfactorily. Whereas the full ROMS model takes 9 days on a powerful computing cluster to compute the physics simulation for 77 days, the box model simulates physics and biology for the same interval in 5 s on a personal computer, and a full year in under 1 min. The exchange matrix mixing model is a fast, cost effective, and convenient way to simulate daily variation of complex estuarine physics in ecological modeling at appropriate scales of space and time. 相似文献
18.
Photoelectro-Fenton was applied for the removal of acid yellow 36 (AY36) from synthetic aqueous solution using iron electrodes. A Box–Behnken design was used for optimization of the effects of pH, H2O2 concentration, current density, and reaction time. Individual effects of these variables were more important than their interaction effects. The derived model was in good agreement with the experimental results. Total organic carbon was determined in solution and sludge in order to clarify the removal mechanism. Increase of H2O2 concentration and current density led to domination of oxidation and coagulation mechanisms, respectively. The effects of scavenging and inhibiting agents were also investigated: (1) presence of alcohols can reduce the efficiency through competition with dye for reaction with hydroxyl radicals; (2) anions (NO3?, HCO3?, and H2PO4?) scavenged hydroxyl radicals and reduced decolorization of AY36. 相似文献
19.
Weng HX Yan AL Hong CL Qin YC Pan L Xie LL 《Environmental geochemistry and health》2009,31(3):401-411
Radioactive iodide (125I) is used as a tracer to investigate the fate and transport of iodine in soil under various leaching conditions as well as
the dynamic transfer in a soil–plant (Chinese cabbage) system. Results show that both soils (the paddy soil and the sandy
soil) exhibit strong retention capability, with the paddy soil being slightly stronger. Most iodine is retained by soils,
especially in the top 10 cm, and the highest concentration occurs at the top most section of the soil columns. Leaching with
1–2 pore volume water does not change this pattern of vertical distributions. Early breakthrough and long tailing are two
features observed in the leaching experiments. Because of the relatively low peak concentration, the early breakthrough is
really not an environmental concern of contamination to groundwater. The long tailing implies that the retained iodine is
undergoing slow but steady release and the soils can provide a low but stable level of mobile iodine after a short period.
The enrichment factors of 125I in different plant tissues are ranked as: root > stem > petiole > leaf, and the 125I distribution in the young leaves is obviously higher than that in the old ones. The concentrations of 125I in soil and Chinese cabbage can be simulated with a dual-chamber model very well. The biogeochemical behaviors of iodine
in the soil-cabbage system show that cultivating iodized cabbage is an environmentally friendly and effective technique to
eliminate iodine deficiency disorders (IDD). Planting vegetables such as cabbage on the 129I-contaminated soil could be a good remediation technique worthy of consideration. 相似文献
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