Technical Challenge:

Dispersion modelling – also referred to as Air Quality Modelling – a powerful tool that simulates air pollution associated with industry, mining, intensive agriculture, infrastructure and urban activities.

What is an Air Dispersion Model?

A model is a simplified picture of reality. It doesn’t contain all the features of the real system but contains the features of interest for the management issue or scientific problem we wish to solve by its use.

An atmospheric dispersion model is a:

• Mathematical simulation of the physics and chemistry governing the transport, dispersion and transformation of pollutants in the atmosphere
• Means of estimating downwind air pollution concentrations given information about the pollutant emissions and nature of the atmosphere.

Dispersion models can take many forms. The simplest are provided in the form of graphs, tables or formulae on paper.

The process of air pollution modelling contains four stages (data input, dispersion calculations, deriving concentrations, and analysis). The accuracy and uncertainty of each stage must be known and evaluated to ensure a reliable assessment of the significance of any potential adverse effects.

Purpose:

Dispersion models are integral to:

• Environmental impact assessment studies for development approval (or) license
• Investigations of complaints or pollution incidents
• Pollution control, management and reduction studies
• Health-risk assessment studies
• Pollution forecasting and online modelling tools
• Optimization studies

Figure: Overview of Air Dispersion Modeling Procedure

Approach / Methodology

Our integrated approach brings together a comprehensive range of services to help our clients meet legislative requirements and their own internal targets. Specific services provided are:

• Air Quality Monitoring;
• Validation of Continuous Emissions measurement;
• Greenhouse Gas (GHG) Consulting.
• We always begin with a thorough questionnaire about your current situation and the on-site mission.
• Our mission typically covers equipment deployment, stack emission measurement, report drafting,
• Consulting to decrease or optimize emissions, and periodical follow-up.

AERMOD/ISC

 CALPUFF

We provide variety of air quality modeling services using EPA, Guideline models namely AERMOD, ISC3, ISCE-Prime, AERSCREEN, SCREEN3 as well as specialized use models like SDM, AFTOX, and CALINE.

Air Dispersion Modeling predicts how pollutants are dispersed in the atmosphere from different pollution sources taking into account building influences, topography, meteorology, downwind distances and other factors. Air dispersion modeling is a mathematical simulation of how air pollutants disperse in the ambient atmosphere. The simulation uses mathematical equations and algorithms to characterize the atmospheric processes that distribute an air pollutant emitted by a source over a wide area. These models are used to estimate or to predict ground level concentration ( GLC) at selected downwind receptor locations of air pollutants  emitted from sources  such as Industrial plants, mines, vehicular traffic or accidental  Chemical releases.

Which Dispersion Model to use?

One of the key elements of an effective dispersion modelling study is to choose an appropriate tool to match the scale of impact and complexity of a particular discharge. When choosing the most appropriate model the principal issues to consider are:

• The complexity of dispersion (e.g. terrain and meteorology effects)
• The potential scale and significance of potential effects, including the sensitivity of the receiving environment (e.g. human health versus amenity effects)

The choice of an appropriate dispersion model is heavily dependent on the intended application.

iFluids Engineering helps to provide the right solution and necessary recommendation with results for the precise decision for your assessment studies…