Possible Causes and Hazards of NOx Gases Evolved after Surface Blasting (original) (raw)

Overview of Post-Combustion Nox Emission Control Mechanism in Indian Coal Fired Power Plants

International Journal of Engineering Applied Sciences and Technology

The importance of Coal in generation of electricity is well established. But, during the combustion of coal for generation of electricity, oxides of nitrogen (NOx) are also released. These oxides of nitrogen are pollutants which have an adverse effect on both the human life as well as the environment. Due to the increased pollution level from Coal Fired Power Plants, Ministry of Environment & Forests (MOE&F) on Dec 2015, announced stringent standards for coal based thermal power plants under the Environment Protection Act of 1986. Though various NOx control systems have been installed and functioning properly worldwide, but their provenness in the Indian scenario is yet to be established. As the coal in which the Indian power plants operates have a very different characteristics than the coal used abroad for power plants. This paper aims to address and explore the various methods and challenges in reducing the NOx emissions from Coal Fired Power Plants while firing Indigenous coal.

Prevention and Origin of Exceptional Deleterious Gas Compositions in Coal Mine

Procedia Engineering, 2011

The abnormal content of gas compositions of H 2 S, CO 2 , CO and N 2 under coal mine has close relationship of safe production and comprehensive utilization of coal gas. According to original analyses of anomalous accumulation characteristics of the above-mentioned gas in China, the paper suggests that abnormal thermochemistry effect, osmosis effect of surface water, sealed effect of coalseam floor, coal types and coal metamorphose degree are the main factors which contribute to abnormity of deleterious gas compositions. Based on study of gas origin, primary measures for prevention and control of deleterious gas in coal excavating course were brought forward. The research has guiding significance for safe production of coal mine.

The impact of blasting on the environment in the open pit mining

Mining and Metallurgy Engineering Bor, 2017

In the open pit mining of mineral raw materials, blasting, whose role is to break the undisturbed mass for easier loading, is the necessary technological phase. In the mass blasting at the open pits of metal ore, there is a rise of cloud composed of gases and dust, blasting mining products, which have negative effects on the surrounding environment. This work presents the calculations of a cloud size, concentration of gases and dust in blasting.

Emission Characteristics of CO and NOx from Tunnel Blast Design Models: a Comparative Study

Polish Journal of Environmental Studies, 2021

A large number of toxic gases such as carbon monoxide (CO) and nitrogen oxides (NOx) are produced from the blast models during the drill and blast tunneling excavation. However, the emission characteristics of blast design models have never been mentioned in previously published studies. To acquire the cleanest blast model and reduce environmental pollution, this paper for the first time compares the emission characteristics of CO and NOx from three traditional blast design models, i.e., NTNU, Swedish, and China models, which is the most used in tunneling. Firstly, the detailed blasting parameters of three models are put forward based on one certain 42.3m 2 cross-section tunnel. After that, the emission characteristics of each model is evaluated based on the indexes of total emission, emissions per area, and emission increment. Meanwhile, the tunnel face of the models is divided into four functional sections, i.e. cut zone, stoping zone, lifter zone, and contour zone to explore the influence of functional blastholes on gas emissions. Finally, these results indicate that the CO and NOx emissions of the China model are the least, followed by Swedish and NTNU models. And the total emissions are dominated by the stoping blastholes. Therefore, it is effective to reduce environmental pollution by adjusting the parameters of the stoping zone. This research can provide a reference for the tunnel engineers to design blast models to reduce environmental pollution.

A Study on Blast Induced Effects on Environment

IRJET, 2022

Mining activity plays a major key role in the development of any country. The development of the nation depends on the industries and most of the industries requires raw material to run it. Mining is the basic source of raw material for most of the industries. Blasting is the economic way for the extraction of the minerals and execution of blasting will results in various environmental effects. In the current study the effect of blast induced ground vibration and air over pressure on environment was studied.

Evaluation of Hazard of Mine Gas emissions at the Surface

The paper presents principles of the method of measuring the concentration and the flow rate of gas emitted from various underground spaces by new evaluation criteria, however mainly from the point of view of consequences of risks associated with gas emissions in semiclosed and closed spaces, in areas affected by the mining of mineral raw materials or mining claims already abandoned.

NOx and SO2 Emission During OXY-Coal Combustion

Chemical and Process Engineering, 2000

The paper presents results of coal behaviour during combustion in oxy-fuel atmosphere. The experiment was performed using 3 meter long Entrained Flow Reactor and 1 meter long Drop Tube Reactor. Three hard coals and two lignites were analysed in order to investigate NOx, SO2 emission and fly ash burnout. The measurements were performed along and at the outlet of a combustion chamber for one- and two - stage combustion. In the second stage of the experiment, kinetic parameters for nitrogen evolution during combustion in oxy - fuel and air were calculated and the division of nitrogen into the volatile matter and the char was measured. The conducted experiment showed that emissions in oxy - fuel are lower than those in air.

[Experimental investigation on emission characteristic of NOx during micropulverized coal oxidation]

2008

The main purpose of blending the Jatropha biodiesel with clean diesel is to decrease the viscosity of the Jatropha biodiesel and improve volatility of biodiesel without changing the molecular structure. The biodiesel shows better performance at all proportions of biofuel blended. Among the different proportions of biodiesel blends, Jatropha shows the best performance at 20% blend. The emission of HC, CO, particulate and smoke is considerably lower than the complete diesel fuel and on the other hand NOx emission is high. Interestingly, the particulate emission was reduced approximately 10 to 20% at maximum load. Therefore, it is concluded that the significant reduction in PM emissions would help in improving the environmental conditions.

NOx Emission in Iron and Steel Production: A Review of Control Measures for Safe and Eco-Friendly Environment

Iron and steel manufacturing involved preparation of raw materials through processes such as sintering, pelletizing and coke making. During these processes, pollutants such as Sulphur (iv) oxides (SO 2 ) Carbon II oxides (CO), Nitrogen oxides (NO X ), Volatile organic compounds (VOC) and Particulate matter (PM) etc. are emitted. The present work is aimed at describing some mitigation technologies of controlling emissions in iron and steel production. The processes involved in the production of iron and steel using Blast Furnace (BF) and Basic Oxygen Furnace (BOF) has been described. The mitigation technologies of controlling emissions were analyzed and discussed with environmental impacts based on the economical and technical factors. In this work, the data presented is based on existing reviews. The combination of low NO X burner (LNB) and Selective catalytic reduction (SCR) is capable of reducing emission for up to 90% and above. Emissions of other pollutants into the atmosphere as a result of ammonia slip, formation of acids and other gases are harmful to the environment and causes damage to the SCR systems. Installation and operation cost are the major impacts of the SCR technology in the process of iron and steel production.