Archivo de la etiqueta: Engineering

Calpuff-calmet modeling system

1. Introduction

Nowadays, due to the fast expansion of commercial development and population rise, polluting of the environment has become probably the most serious problems in the world, especially in large cities and consequently, the problem of air pollution and its control has become increasingly. Fossil gas combustion, especially which based on oil and coal is among the major causes of the environmental problems affecting both native and global levels. Nevertheless, several countries remain applying fossil fuels as major energy, specifically in developing countries.

Electricity intake in Iran offers experienced a considerable growth during recent years because of economical creation, industrialization and population rise. In 1973, electric strength generation per capita was 310 kWh, which risen to 2935 kWh in 2008. Electricity technology using fossil fuels has destructive effects on environment.

Due to Iran’s environmental circumstances, electricity generation is mainly performed by thermal vitality plants, so that near 85% of the required electric energy is made by thermal power plants. Gas-fired power plants are the dominant portion which accounted up to 62% of total power generation. Oil-fired power plants made 22.4% and 14.7% created from hydroelectric vegetation. Although hydroelectric plants generate 14.7% proportion of plant life in Iran, these vegetation have produced only 5.1% of the power due to a fall in precipitation in the last few years. Gas (71.3%) may be the largest way to obtain fuel for electricity generation followed by heavy oil (15.8%) and gas oil (12.4%). Although, the key fuel of power plants is gas, the environmental problems are still concerned

Air quality is a significant determinant of human overall health. Meteorology plays an excellent role in determining air quality changes downwind of emission resources. Both the wind and atmospheric steadiness greatly affect dispersion circumstances. Local influences due to terrain and land-cover elements can also be important. Atmosphere dispersion and deposition versions are equipment for estimating concentrations of weather pollutants and deposition costs due to industrial or other emission options (Prince Rupert Airshed Analysis). Air quality styles are instrumental in featuring valuable insights into the processes mixed up in transport, dispersion and chemical transformation of pollutants in the ambiance .These models employ mathematical equations and numerical methods to describe the concepts involved in the atmosphere.

In modern times, CALPUFF model has good effectiveness in the simulation of many types of pollutants under complicated topography, especially in the region bigger than 50 km. CALPUFF can be run in any specific location around the globe, and for any modeling type period selected by the user. Because of its flexibility, CALPUFF has been used in several clinical tests.

Over the past years, several CALPUFF-aided case studies have been published. Shiyao Li et al. (2016) used CALPUFF model to simulate the spatial distribution of sulfur dioxide in Urumqi and analyzes the foundation contribution to areas where in fact the SO2 concentration is substantial. Prueksakorn et al. (2014) applied WRF/CALPUFF modeling system and multimonitoring solutions to investigate the result of seasonal variants on odor dispersion in Changwon Town of South Korea. Abdul-Wahab et al. (2011) used CALPUFF program to measure and simulate the dispersion of sulfur dioxide (SO2) at the Mina Al-Fahal Refinery in the Sultanate of Oman. Abdul-Wahab et al. (2013) used CALPUFF to review the result of meteorological conditions on the dispersion of an accidental release of hydrogen sulfide (H2S). Abdul-Wahab et al. (2015) used CALPUFF to assess the standard of the proposed Miller Braeside quarry expansion in Canada. Hyung-Don Lee et al. (2014) applied WRF-CALPUFF application to simulate concentration distributions of typical atmosphere pollutants (PM10 and Thus2) in the Ulsan Petrochemical Industrial Complex (UPIC), and statistics are computed to look for the models’ capability to simulate observations.

In this study, a CALMET diagnostic unit nested to WRF version simulation is evaluated by comparison to surface weather measurements, along specific intervals. Then your CALPUFF dispersion version was employed to simulate and predict the concentration of SO2, NOX, CO and PM10 that will be emitted from the Shahid-Montazeri vitality plant (SMPP) of Esfahan, Iran. The main goal of the study is to judge the ability of the CALPUFF version to simulate the concentrations of As a result2, NOX, CO and PM10 in the near by of power plant for distinctive topographical and climatological conditions of the analysis area. First, the amounts of pollution exhausted from the stacks and the ambient concentrations of pollution due to the emitted gases from the stacks of Shahid-Montazeri ability plant have been monitored in four receptors (Figure 1). Then your ambient concentration degrees of pollution have already been simulated for the receptors, using CALPPUF Lagrangian Gaussian puff version. Finally, the evaluation of model prediction effects and the monitored concentrations have been done through statistical research.


2. Model description

Technical description of CALPUFF-CALMET modeling system

CALPUFF is probably the US Environmental Protection Agency’s (EPA) desired models for assessing transport of pollutants and their results, on a case-by-case basis, or for certain near-field applications involving complex meteorological conditions. The modeling system contains three main components and a set of preprocessing and content processing programs. The primary components of the modeling system are CALMET (a diagnostic 3-dimensional meteorological unit), CALPUFF (an air quality dispersion model) and CALPOST (a post processing package).

CALMET is usually a diagnostic meteorological model which can make use of topography, territory type, meteorological observation info and meteorological simulation data to analysis of wind and temperature areas based on the mass conservation equation. Aside from the wind and temperature fields, CALMET determines the 2D areas of micro meteorological variables needed to perform dispersion simulations (mixing height, Monin Obukhov duration, friction velocity, convective velocity and others). The caliber of a meteorological preprocessor is certainly one of the primary determinants of the entire quality of the air dispersion model, and this is particularly authentic for the CALPUFF/CALMET modeling system in a wide range of conditions. The main purpose of CALMET is to get the greatest meteorological data predicated on the available information. Specifically, CALMET can get measured info, modeled data (i.e., made by a meteorological unit like MM5 or WRF), or both. Whenever a high-resolution terrain data set is available, CALMET is capable of using these details to estimate localized deviations from meteorological data measured or modeled at a coarser image resolution (Scire J.S).

CALPUFF can be a multi-species non-steady-condition puff dispersion model that simulates the consequences of period and space varying meteorological circumstances on pollutant transportation, transformation, and removal. CALPUFF allows the use of on-site turbulence measurements of the horizontal and vertical Gaussian dispersion coefficients, but also allows for the utilization of similarity theory and micrometeorological variables, produced from meteorological observations and surface characteristics, to acquire these coefficients. CALPUFF utilizes a Gaussian puff formulation to calculate the concentration of a pollutant (or spores, in our request) at any given site downwind, and the deposition at user’s specified locations at walk out (Use of a complex air pollution unit to estimate W. Pfender). CALPOST can extract CALPUFF simulation data according to customer’s demand (Spatial distribution and source analysis of SO2 concentration in Urumqi).

3. Methodology

a. Description of review area and model domain

Isfahan is found in the central Iran inside plains stretching along the Zayandeh Rood River. The city is located in a comparatively mountainous area in the heart of the Iranian Plateau and stretches from the snowy Zagros Mountains in the West to the East and North-central deserts of Iran. There exist various climatic conditions in metropolis thanks to regions with different altitudes. The outstanding top features of Isfahan are little rainfall,

average significantly less than 125 mm. Isfahan is definitely found in 32.67N, 51.83E, and elevation 1550-1650 m, with more than 1.7 million inhabitants ( There are more than a million automotive and heavy duty vehicles using diesels, gasoline, and natural gas in Isfahan. This town is known as the largest industrialized area in Iran, where there are many professional states, steel businesses, and etc. Addititionally there is one of the primary energy plant of Iran.

Shahid-Montazeri steam power plant of Esfahan is located 15 km to the northwest of Isfahan along the Isfahan-Tehran highway subsequent to Isfahan Refinery and Petrochemical Complex in a 2.2 million m2 terrain (Analysis of synchronous execution of full repowering and solar assisting in a 200 MW steam ability plant, a research study) (Figure 1). This ability plant has 8 similar steam devices each with a potential of 200 MW. Montazeri plant can be a steam vitality plant which is lately use gas. However, Montazeri uses large oil during the cold days because of increasing the domestic heat.

The study area is situated around as Montazeri electric power plant, with a complete capacity of 1600 MW and two large smoke stacks (205 agl-m height, above ground level meters height and 1725 foundation elevetion) with four independent liners (one per boiler) in the same cement shaft that are decided on level sources (Figure 2). Subsequently, it should be regarded as eight different point sources practically located at the same stage; alternatively, it might be regarded as a two point sources, with an emission and stack section as the sum of the four liners (Validation of CALMET/CALPUFF version simulations around a big power plant stack).

In this study, dispersion of As a result2, Nox, and particulate subject (pm10) emitted from the Montazeri electric power plant over the Esfahan basin was evaluated for two periods of — days and nights (from 10 to 31 January 2000). A simulation domain of 100×100 km2 was determined by the power plant positioned at the center, so as to cover any pollutant source local impact. This spot is split into 10000 grids, how big is which can be 1 km – 1 km. The southwest part of the domain is located at longitude 50.96E, latitude 32.35N. The northeast part is situated at longitude 52.03E, latitude 33.24N and the elevation of the analysis area varies from 1500 to 2800 m. Desk 1 represents the information model input which can be used for defining the case study meteorological domain.

b. Emission data

The main sources of pollutants in Montazeri vitality plant will be resulted from exhaust gases of the stacks which cause air pollution in the energy plant area and it’s really surrounding. The ideals of SO2, NO, NO2 and PM10 emissions from the stacks of Montazeri electricity plant have been measured by Testo 350-XL gadget for gases and ISOSTACK BASIC product for particulate maater, during the period of simulation. The data of stack attributes and the emission charge of the pollutant have already been presented in Tables 2.

This release huge quantities of sulfur dioxide due to Steam power crops of Iran aren’t built with FGD systems to lessen SO2 emissions, and thereby, the emission factor of the pollutant is only influenced by electricity technology efficiency and sulfur percentage of the consumed hefty oil.

In this study, we used data observed from four monitoring station to measure hence2, nox and pm 10 (figure 1). Located area of the monitoring stations (receptors) possesses been presented in Cartesian coordinate program in Desk 2. Measurements at the monitoring station were completed based on the average hour concentrations.

c. Meteorological data

Surface hourly observations in TD-3505 formatting were received from the Integrated Area Hourly Database (ISHD) supported by the united states National Climatic Data Middle (NCDC) . Info was extracted hourly for the entire modeling period from March 10, 2012 at 00h00 UTC to March 12, 2012 at 23h00 LST. Because of the large number of missing data of the other area meteorological parameters (such as for example: pressure, ceiling height and cloud cover) just temperature and wind velocity were validated. The purpose of extracting this info was only to measure the reliability of the calmet unit to simulate the vertical profiles of wind and heat range. Figure 3 shows the location of the meteorological station found in this study and a information of the top stations is presented in table 3

d. Modeling approach

The initial period of CALPUFF modeling program consists of the derivation of 3d meteorological wind fields for the study area applying CALMET a diagnostic meteorological style (Estimated Public Health Contact with H2S Emissions from a Sour Gas Very well Blowout in Kaixian County, China). The source of CALMET model includes geophysical data (land use categories and terrain elevations), meteorological data (surface and higher air flow meteorological observations or meteorological fields made by prognostic models) (A study of the effects of car emissions on the ambiance of Sultan Qaboos University in Oman). Due to lack of the top and upper air flow meteorological data in the study area we used the Weather Analysis and Forecasting (WRF: edition 3.5.1) style to simulate of meteorological circumstances. The Weather Exploration and Forecasting (WRF), a prognostic meteorological unit, was used to calculate the hourly three-dimensional meteorological areas For CALMET unit (Applications of WRF/CALPUFF modeling system and multi-monitoring). The WRF unit description presented in Table 2. Initial conditions and boundary conditions are provided by the 1.0 degree National Centers for Environmental Prediction (NCEP) Final Examination (FNL) at 6-h intervals (Use of high-quality MM5/CALMET/CALPUFF program: SO2 apportionment to quality of air in Hong Kong). Info in WRF output data could be interpreted and changed into a format compatible with CALMET by CALWRF software (Scire et. al.2000b).

CALMET requires geophysical info to characterize the terrain and property use parameters that possibly impact dispersion. Terrain features impact flows, build turbulence in the atmosphere, and are potentially subjected to higher concentrations of elevated puffs. Different land make use of types exhibit variable qualities such as surface roughness, albedo, Bowen ratio, and leafarea index that also have an effect on turbulence and dispersion (The usage of an atmospheric dispersion unit to determine influence regions in the Prince George, B.C.).

Terrain elevation for the CALMET was obtained using the TERREL processor. The model was executed with terrain maps supplied by Consultative Group on International Agricultural Exploration (CGIAR) and the Consortium for Spatial Details (CSI) website (, Data were collected as part of the Shuttle Radar Topographic Objective (SRTM) and prepared by CSI into 5 x 5 level tiles at 90-metre resolution. Land characteristics in the domain were extracted using the CALMET pre-processor CTGPROC. The input land make use of maps were obtained from america Geological Survey (USGS) websites in GeoTIFF structure. Terrain qualities map in the study area has been displayed in Fig. 3.

To provide meteorological source to the CALPUFF version, the CALMET diagnostic unit and WRF mesoscale prognostic model had been coupled. The CALPUFF style uses the output record from CALMET together with source, receptor, and chemical substance reaction details to predict hourly concentrations.

e. Statistical Data Analysis

To determine the reliability of the simulation data, verification of simulated values applying the WRF and CALMET models was conducted for surface temperature and wind rate at surface area monitoring station using countless statistical indicators. The statistical verification of model functionality in this research was performed employing four statistical indicators namely the Bias Error (B), Gross Mistake (E), Fractional Bias (FB), Normalized Mean Square Mistake (NMSE), Root Mean Square Mistake (RMSE) and Index of Agreement (IOA). The formulas used to derive these four indicators receive in Equations