Nox emissions pdf

In the upper to 0. Phase II also placed limits on atmosphere, ozone occurs naturally and shields the earth Group 2 boilers other boiler types to 0. In , the Environmental Protection plant health. Exposure to ozone irritates human lungs, Agency proposed further reductions to 0. Ground-level ozone interferes with The compliance options available to fossil generators the ability of plants to produce and store food, so that fall into three distinct categories: emission control tech- growth, reproduction and overall plant health are nologies, fuel switching, and the use of NOx emission compromised.

It is also a major component of urban allowances. The proposed plans used in the development smog Indiana Department of Environmental Manage- of these scenarios did not include the use of allowances.

There are two main categories of emission control tech- While NOx emissions rates vary from plant to plant nologies, combustion control and post-combustion tech- according to the design of the plant and the character- nologies. Low NOx burners, which work at the combus- istics of the fuel, an uncontrolled emission rate of 1.

Post-combustion control is done The E-mail address: gotham ecn. Gotham et al. The statewide electricity prices tems, a reagent is injected into the flue gas in the furnace reported here were determined using energy-weighted within an appropriate temperature window. The NOx and reagent ammonia or all customer groups combined. A typical SNCR system consists of reagent storage, multi-level reagent- injection equipment, and associated control instrumen- 2.

Methodology tation. This is accomplished by con- Utility Forecasting Group, This model projects trolling the fuel and air mixture to alter the size and electric energy sales and peak demand as well as future shape of the flame. These Fuel switching involves replacing coal or oil as a factors describe the future of the Indiana economy and source of fuel with natural gas to lower NOx emissions.

Com- ral gas fuel or to partial fuel switching. Partial fuel binations of econometric and end-use models are used to switching consists of two main options: seasonal switch- project electricity use for the major customer groups— ing and natural gas reburn.

Seasonal switching involves residential, commercial, and industrial. The modeling using natural gas as the fuel source during the summer, system predicts future electricity rates for these sectors which is the primary ozone season.

Natural gas reburn by simulating the cost-of-service based rate structure tra- involves co-firing a small amount of natural gas 10— ditionally used to determine rates under regulation. The costs associated this type of rate structure, ratepayers are typically allo- with fuel switching vary greatly depending on the boiler cated a portion of capital costs and fixed operating costs size and design as well as access to natural gas.

As sistency in the analyses. The other major model driver, a result of this reliance on coal, Indiana ranks second in the price of electricity, varies according to the results of the United States in the amount of NOx emitted annually the scenario. Therefore, any changes in customer Energy Information Administration, Therefore, demand from one scenario to another result entirely from NOx emissions reduction regulations will significantly the NOx reduction requirements.

These pliance strategies for reduction of NOx emissions from demands are then sent through a generation dispatch coal-fired electric utility generation plants.

All of these model to determine the operating costs associated with scenarios involve retrofit of control devices to reduce meeting the demands. Four of the scenarios pertain to a mines a new set of electricity prices for each utility.

This is in contrast to an emission rate of repeated until an equilibrium state is reached where 0. Thus, the model of the Clean Air Act Amendments. The four 0. In the scenarios capacity is needed for the utilities to adequately meet the common control strategies involve retrofit of SNCR, the load. This is accomplished through another iterative SCR, and in some cases, combustion control modifi- process with the costs associated with acquiring this cations.

Since the demand levels listed in Table 2. However, the cri- 4 are the sources for baseline emissions and the teria for acquiring new capacity are held constant to efficiency and costs of the technology choices. NOx control technologies will affect the price of elec- Scenario 1 tricity in several ways.

In this modeling system, the capi- Both baseline emission rates and technology tal cost of equipment is captured in the rates and finance efficiency and costs derived from EPA. Allowable model, using a traditional regulated rate of return. The emissions 0. These impacts include changes in fuel costs Baseline emission rates derived from EPA.

Tech- resulting from changes in overall plant efficiency, nology efficiency and costs derived from a combi- increased maintenance costs, and changes to generation nation of utility sources and published information. Scenario 3 Both baseline emission rates and technology efficiency and costs derived from a combination of 3. Nox control scenarios utility sources and published information.

Allowable emissions 0. Scenario 5 Same as Scenario 3 with allowable emissions low- ered to 0. Cost—price—demand feedback loop. In addition to the IDEM scenario assumptions, further The month installation period used in these analy- assumptions were made in order to perform this analysis ses does not represent the total time needed for planning, using the traditional regulation modeling structure.

These processes take a consider- These assumptions pertain to future capital costs for able amount of time before the actual physical construc- retrofit control equipment, expenditure streams for retro- tion begins. Likewise, the month time period does not fit equipment installation, and the timing of retrofit represent the time that the generating unit must be taken installations. While these assumptions are reasonable, it out of service for the installation process.

The downtime should also be recognized that they could be subject to used in these analyses were 2 weeks for SNCR and 6— further refinement in subsequent analyses, as further 10 weeks for SCR installations. Since installation schedules for NOx controls were It was assumed that capital costs for NOx retrofit con- unavailable, installation dates were assigned for all retro- trol equipment will escalate at an annual rate of 2.

The procedure used to assign on-line dates per year from the dollar base year estimates pro- is somewhat arbitrary and should be refined in future vided by IDEM. This assumption applies to all control analysis.

On-line dates were assigned by attempting to technologies including SNCR and SCR devices as well minimize the capacity off-line for retrofits and delaying as combustion modifications. While this escalation rate retrofits until required for compliance on an individual assumption is open to debate, it is consistent with the utility basis.

For example, if a utility is required to retro- assumptions employed in preparing the base case which fit two large coal units, the units were assigned retrofit includes no NOx emission reductions from current lev- dates of Fall and Spring ; three large units els. A more reasonable allo- for all affected generation units will be installed over a cation of retrofit dates would explicitly incorporate the month period for all retrofit options including SNCR, utilities maintenance schedules and attempt to overlay SCR, and combustion control.

It was further assumed final installation with major maintenance periods as well that the stream of expenditures for such retrofit is evenly as attempt to coordinate installation outages across util- divided across this month period. Since the fore- ities where possible. The optimal temperature, voltage, and the mole ratio of propane in NOx conversion to N2 and O2. Plasma reactor acts as primery treatment in the direct mitigation of NOx into neutral and non-poisonous molecules of O2 and N2.

Yarahmadi, R. Some other advantages of non-thermal Driven by world-wide emission regulations, there is plasma are its mitigation performance potentiality in a need for the removal of nitrogen oxides in engine exhaust spreading resource matrix especially in oil and gas gases with oxygen excess lean-burn and diesel engines industries as well as in petrochemical complexes [9].

The gas velocity control and space time of the exhaust Nowadays, the technical application of plasma gas from the fixed and removable resources in mixing is expanding rapidly and this expansion is closely related and completing the final reaction of the plasma treatment to the outstanding or better to say unique characteristics are so influential that it is possible to use this potentiality of plasma technology[1, 2,3].

Due to the technical considerations 10 years now to reduce the NOx emissions by a in designing the geometric structure of the plasma non-thermal plasma NTP in the gas phase. One of the the molecules in the gas phase producing reactive species by-products of this process is Ozone as an unwanted radicals, excited molecules that undergo further reactions.

Hence, the identification and specification essentially at the temperature of the environment cold of the factors affecting NOx treatment and studying plasma. NOx in exhaust gases. Moreover, commitment to the national and in a coaxial reactor by dielectric barrier discharges, international obligations, treaties, protocols, conventions, using a glass or a ceramic tube as a dielectric barrier mm and resolutions aimed at reducing the emission high,11mm Dia , 1.

The main NOx contamination outer wall. The gas discharges were excited by application controlling techniques include selective, non-selective, of a high-voltage pulse generator ca. In fact, plasma technology due to the simplicity of In this experiment, the discharge mechanism with treatment process, low cost of designing, manufacturing, dielectric barriers in the non-thermal plasma process maintenance, and its inde-pendence from the chemical under the atmospheric conditions and the temperature of and mechanical equipments has got special significance [].

The advantages of this process are an increase in the The entering temperature of the plasma reactor was interaction potentialities and a natural fusion of first measured by some thermal sensors with an accuracy the contaminants and influential factors on the conversion of 0.

In addition, in order to control the factors monitoring of the system. Examination of the Optimized Conditions NOX ppm. SN Controller and then conducted to the mixture pa NO,in The main aim of this method was to obtain logical and The conversion coefficient of NOx to other products accurate information and results through a practical except NOx can be worked out from the following formula: experimental design.

In the other method, with quantitative, and qualitative objectives and through some For mass balance, before and after the plasma reactor, Grap samples accumulated in the glass containers, all all the concentrations ppmv were changed into unwanted by-products were analyzed. This analysis was the mass density. Also in this study comprisable behavior carried out by means of mass spectrometric GC-Mass or of air mixture was evaluated [].

V Fig. The results of the previous studies indicated that the response variable. Table 1. In addition, compared to the conversion coefficient of According to the research method, with a certainty of NOx, that of NO had more potential. The analysis of the obtained results from The trends of the factors affecting NOx conversion the conversion of NO gas in the experiments revealed that in four levels were predicted.

Because of the dependence of the space velocity factor on Plot of x-conversion No,NOx the temperature condition and its low effect on NO 0. Variable 0. The direct conversion of NOx to N2 0.