Related Experiment Videos
Validation for a recirculation model
1Air Force Institute of Technology, Wright-Patterson Air Force Base, Ohio, USA.
Applied Occupational and Environmental Hygiene
|April 25, 2001
Summary
Recirculating air in painting operations reduces volatile organic compound (VOC) emission control costs. A validated computer model predicts compliance costs and indoor air pollutant levels, aiding facility management.
Area of Science:
- Environmental Engineering
- Occupational Health and Safety
- Industrial Hygiene
Background:
- Recent Clean Air Act regulations impose restrictions on painting operations due to volatile organic compound (VOC) emissions.
- Treating large volumes of dilute VOCs is costly; air recirculation offers a potential cost-saving compliance strategy.
- Air recirculation may increase indoor pollutant concentrations, posing risks to employee safety.
Purpose of the Study:
- To develop and validate a computer model for predicting compliance costs and indoor air concentration changes associated with air recirculation in painting facilities.
- To assess the model's accuracy using real-world data from an aircraft painting facility.
- To evaluate the impact of varying recirculation levels on cost and safety.
Main Methods:
- Development of a computer model in Microsoft Excel 97 using product usage and mass balance equations.
- Validation of the model using air sampling data and vendor cost quotes from a C-130 aircraft painting facility.
- Comparison of model predictions for air concentrations (strontium chromate, isocyanate) and capital costs of VOC control devices against collected data.
Main Results:
- Model predictions for strontium chromate and isocyanate air concentrations generally fell between the minimum and maximum measured values, often near the maximum.
- Capital cost predictions for thermal VOC control devices showed variability, with estimates ranging from 14% underestimate to 50% overestimate compared to average quotes.
- A sensitivity analysis of model variables was conducted.
Conclusions:
- The developed computer model serves as a valuable tool for evaluating the economic and safety implications of air recirculation in painting operations.
- The model provides reasonable estimates for air concentrations and costs, aiding regulatory compliance and operational decision-making.
- Further refinement and validation may enhance prediction accuracy for specific contaminants and cost factors.