ENVIRONMENTAL PROTECTION AGENCY APTI 435: Atmospheric Sampling Course. Student Manual

Transcription

1 ENVIRONMENTAL PROTECTION AGENCY APTI 435: Atmospheric Sampling Course Student Manual

2

3 Table of Contents Chapter 1: An Introduction to Atmospheric Sampling Introduction Sampling Train Design References Chapter 2: Basic Gas Properties and Mathematical Manipulations Temperature The Fahrenheit and Celsius Scales Absolute Temperature Pressure Definition of Pressure Barometric Pressure Torricelli Barometer Fortin Barometer Aneroid Barometer Pressure Transducers Gauge Pressure Absolute Pressure The Concept of Pressure-Head Dalton s Law of Partial Pressure The Ideal Gas Laws Boyle s Law Charles Law The Law for Ideal Gases Molar Volume Gas Density Standard Conditions for Atmospheric Sampling Origin and Definition of Viscosity Kinematic Viscosity Liquid Viscosity versus Gas Viscosity Reynolds Number Summary of Useful Equations Temperature i

4 Pressure Ideal Gas Law Gas Density Viscosity, µ Reynolds Number Units of Measurements Recommended Units Conversion Problems References Chapter 3: Air Measuring Instruments Introduction to Air Movers Relationship of Air Movers to Other Sampling System Components Air Mover Classification Air Mover Selection Criteria Pollutant Concentration and Sampling Time Sampling Rate Required Physical and Chemical Nature of Air to be Sampled Portability of Air Mover Air Mover Noise Air Mover Maintenance Resistance Constant Flow Rate Pumps Definition and Classification Positive Displacement Pumps Centrifugal Pumps Driving Forces for Pumps Characterisitic Curves Selecting a Pump Pump Gauges Ejectors Principle of Operation Driving Forces Sampling Use of Ejectors Liquid Displacers Principle of Operation Sampling by Use of Liquid Displacement Air Displacers ii

5 Evacuated Flasks: Principle of Operation Sampling by Use of Evacuated Flasks Plastic Bags: Principle of Operation Sampling by Use of Plastic Bags Flow Rate Control Control by Diversion Resistance Control Driving Force Control Flow Rate for Sampling Need for Control Control Mechanisms Air Measuring Instruments Introduction Types of Air Measuring Devices Calibration Volume Meters The Spirometer (or Bell Prover ) Primary Standard Displacement Bottle Technique Primary Standard Frictionless Pistons Primary Standard Automated Bubble Flowmeters Automated Dry-Piston Flowmeters Wet Test Meter (WTM) Secondary Standard Roots Meter Secondary Standard Dry Test Meter Secondary Standard Rate Meters Variable-Pressure Meters Head Meters Variable Area Meters Mass Flow Meters Heat Transfer Meters Hot-Wire Meters Velocity Meters Pitot Tube Primary Velocity Standard Standard Pitot Tube Secondary Velocity Standard S-Type Pitot Tube Secondary Velocity Standard Thermal Anemometer Secondary Velocity Standard Sample Problems Problem 1: Volume Conversion to Standard Conditions Problem 2: Orifice Conversion When Used at Other Calibration Conditions Problem 3: Conversion for Different Gas Used with a Rotameter Problem 4: Pump Capacity iii

6 3.14 Additional PM 2.5 Flowmeters and Devices Bubble Flowmeters Piston Flowmeters Mass Flowmeters Orifice Devices Laminar Flow Elements Wet Test Meters Dry Gas Meters References Chapter 4: Particulate Matter Sampling Introduction Principles of Inertial Collection Inertial Sampling Devices Impaction Devices Impingement Devices Centrifugal Separation Devices Virtual Impactors Dichotomous Sampler Collection Efficiency and Penetration Efficiency of Inertial Sampling Devices Definition of Collection Efficiency and Penetration Efficiency 4-21 Impactor Performance Characteristics Properties of Aerosols Affecting Inertial Collection Efficiency Properties of the Collecting Device Influencing Collection Efficiency Limitations and Sources of Error in Inertial Collection 4-24 Inherent Errors in Sample Collection Errors Associated with the Calibration of Collection Devices Errors in Sample Analysis Size-Selective Inlets and Devices for Aerosol Sampling Filtration Sampling Introduction General Considerations The Theory of Filtration Collection Efficiency of Filters Characteristics of Filter Media Sample Problems Gravitational Sampling Dustfall Bucket or Jar Precipitation Collectors iv

7 4.7 Electrostatic Precipitators Introduction Principles of Electrostatic Precipitation Collection Efficiency Specific Applications Thermal Precipitators Introduction Collection Efficiency and Depostion Pattern Advantages and Disadvantages of Thermal Precipitators Summary References Chapter 5: Methodologies and Instrumentation for Particulate Matter Sampling Introduction High-Volume Sampling for Suspended Particulate Matter (SPM) and Air Toxics High-Volume Air Sampling Introduction Development of the High-Volume Sampler Sampler-Shelter Combination Filter Media for High-Volume Sampler Precautions in Filter Handling Calibration U.S. EPA High-Volume Sampling Procedure for TSP Sample Problems Analysis of High-Volume Filters Sampling Accuracy and Precision Accuracy Precision Maintenance Summary FRM for the Determination of Particulate Matter as PM Applicability Principle Range Precision Accuracy Potential Sources of Error v

8 PM 10 Sampler Apparatus Filter Media Calculations Sample Problems FRM and FEM for the Determination of Fine Particulate Matter as PM Reference Methods for PM 2.5 (FRM) Designated Methods for PM Equivalent Methods for PM 2.5 (FEM) Limitations of PM 2.5 Reference and Class I Equivalent Methods5-47 Approved Regional Methods (ARMs) Calculations Sample Problems FRM and FEM for the Determination of Coarse Particles (PM 10 -PM 2.5 ) PM 2.5 Speciation Sampling Continuous in situ Monitoring for Particulate Matter National Core (NCore) State and Local Air Monitoring Stations (SLAMS) Automated Federal Equivalent Monitors Beta Attenuation Monitor (BAM) Tapering Element Oscillating Microbalance (TEOM ) Other Automated PM Methods Mass and Mass Equivalent Visible Light Scattering Visible Light Absorption Electrical Mobility Multi-Elemental Analyzer References Chapter 6: Gaseous Sampling Principles of Absorption Introduction Types of Absorption Physical Absorption Chemical Absorption Collection Efficiency Factors Affecting Collection Efficiency Absorber Characteristics Chemical Characteristics vi

9 Physical Characteristics Determination of Collection Efficiency Absorption Devices Fritted-Glass Absorbers Impingers Summary Current Applications of Absorption in Atmospheric Sampling Principles of Adsorption Basic Principles Types of Adsorption Variables Affecting Gas Adsorption Adsorption Isotherms Adsorbate Characteristics Adsorbent Characteristics Typical Adsorbents Adsorption Losses in Air Sampling Current Applications of Adsorption in Atmospheric Sampling Summary Selection and Performance of Wet Collector Media Introduction Solubility of Pollutant Rate of Reaction Collection Efficiency Retention Characteristics of Absorbent (Solvent) Retention of Gases and Vapor by Chemical Reaction Retention of Particulate Matter Principles of Grab Sampling Introduction Evacuated Containers Air Displacement or Purging Liquid Displacement Inflation Plastic Bag Sampling Syringes Grab Sampling Techniques Current Applications of Whole Air (Grab and Integrated) Sampling in Ambient Air Principles of Cryogenic (Freezeout) Sampling Introduction Concept Equipment vii

10 Single-Stage Units Multistage Units Efficiency Current Applications of Cryogenic (Freezeout) Sampling in Ambient Air Summary References Chapter 7: Standard Methods for Criteria Pollutants Introduction Reference Method and Equivalent Method Criteria Pollutants and Measurement Methods Particulate Matter Ozone Carbon Monoxide Nitrogen Dioxide Sulfur Dioxide Lead References Chapter 8 : Introduction to Ambient Air Sampling for Air Toxics Introduction What are Toxic Air Pollutants? Clean Air Act of Timeline for Air Toxics Monitoring What is Risk? What is a Risk Assessment? Hazard Identification Weight of Evidence for Health Problems of Concern Exposure Assessment Dose-Response Assessment Dose-Response Relationships Risk Characterization Introduction to Air Toxics Methods Monitoring Program Goal and Objectives Description of the Methods Compendium Method TO-11A viii

11 Compendium Method TO-13A Compendium Method TO-15A Compendium Method IO References Appendix A: Statistical Techniques Employed in Atmospheric Sampling...A-1 A.1 Introduction... A-1 A.2 The Data Quality Objective (DQO) Process... A-2 The Seven Steps of the DQO Process... A-2 Outputs of the DQO Process... A-3 A.3 Data Collection Design... A-3 Data Plotting... A-3 A.4 Graphical Analysis... A-4 Frequency Tables... A-4 The Frequency Polygon... A-6 The Histogram... A-6 The Cumulative Frequency Distribution... A-8 Distribution of Data... A-9 Transformation of Data... A-9 The Logarithmic Transformation... A-10 Probability Graph Paper... A-11 Least-Square Linear Regression... A-12 A.5 Measures of Central Tendency... A-14 Arithmetic Average, or Mean... A-14 Median... A-15 Geometric Mean... A-16 A.6 Measures of Dispersion... A-17 The Range... A-17 Standard Deviation... A-18 Coefficient of Variation... A-19 Standard Geometric Deviation... A-20 A.7 Distribution Curves... A-22 The Normal Distribution... A-22 Lognormal Distributions... A-24 References... A-26 Appendix B: Glossary and Acronyms...B-1 B.1 Glossary... B-1 ix

12 B.2 Acronyms... B-28 Appendix C: Conversion Factors and Useful Information... C-1 Appendix D: Compendium of Methods for the Determination of Toxic Organic Compounds in Ambient Air, Second Edition... D-1 Appendix E: Compendium of Methods for the Determination of Inorganic Compounds in Ambient Air... E-1 Appendix F: Theory and Calibration Procedures for the Use of a Rotameter... F-1 F.1 Nomenclature... F-1 F.2 Description of a Rotameter... F-2 F.3 Development of Flow Equations... F-3 General Flow Rate Equations... F-3 Computation of Reynolds Number... F-5 F.4 Common Practices in the Use of a Rotameter for Gas Flow Measurement... F-6 Procedures for the Calibration of a Rotameter... F-7 A Universal Calibration Curve... F-8 Development of a Universal Calibration Curve... F-9 F.5 Use of the Universal Calibration Curve for a Rotameter... F-11 To Determine an Existing Flow Rate... F-11 To Establish a Required Sampling Rate... F-11 To Predict Calibration Curves... F-12 Appendix G: Significant Figures and Rounding Off... G-1 G.1 Working with Numbers Intro Problems... G-2 G.2 Approximate Numbers... G-2 Rule 1 (General)... G-3 Rule 2 (General)... G-3 x

13 G.3 Rounding Approximate Numbers... G-3 Rule for Rounding Approximate Numbers... G-3 G.4 Adding and Subtracting Approximate Numbers... G-4 Truncating Approximate Numbers Following Addition or Subtraction... G-4 G.5 Multiplying and Dividing Approximate Numbers... G-5 Significant Digits... G-5 Truncating Approximate Numbers Following Multiplication or Division... G-6 G.6 Reasonability... G-8 Rule to Meet the Conditions of Reasonability... G-8 G.7 Practice Exercises... G-9 G.8 Answers to Intro Problems... G-10 G.9 Answers to Practice Exercises... G-11 xi