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Formaldehyde (Revised)

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Formaldehyde (Revised) uniti slalm Otiicc of Air Quaky EPA-450/4-9 l-012 Fa”irmmenlid Prolccnan planningAnd Standards March 1991 Awncy Rcrurch Trianale Park. NC 2i711 AIR \“f EPA LOCATING AND ESTIMATING AIR EMISSIONS FROM SOURCES OF FORMALDEHYDE (REVISED) “, ~.,.~,.,~. .~..~.: ~..~.,, ,..~,‘. .;.. .~_. I < I :...;,.....;&;~~~ ,, ., ~_;_ ..,. .,.~..“_,..,..,. -l-s=h -__- EPA-450/4-91-012 LOCATING AND ESTIMATING AIR EMISSIONS FROM SOURCES OF FORMALDEHYDE (REVISED) By Emission Inventory Branch Technical Support Division EPA Project Officer: Dallas Safriet U. S. Environmental Protection Agency Office of Air And Radiation Office of Air Quality Planning and Standards Research Triangle Park, NC 27711 March 1991 This report has been reviewed by the Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency, and approved for publication as received from the contractor. Approval does not signify that the contents necessarily reflect the views and policies of the Agency, neither does mention of trade names or commercial products constitute endorsement or recommendation for use. CONTENTS Figures ..................... iv Tables ..................... v 1. Purpose of Document .............. 1 2. Overview of Document Contents ......... 3 3. Background ................... 5 Nature of Pollutant .............. 5 Overview of Production and Uses ........ 8 4. Formaldehyde Emission Sources ......... 13 Formaldehyde Production ............ 13 Urea-Formaldehyde and Melamine-Formaldehyde Resin Production ............... 23 Phenol-Formaldehyde Resin Production ...... 29 Polyacetal Resin Production .......... 41 Hexamethylenetetramine Production ....... 49 Pentaerythritol Production ........... 52 1,4-Butanediol Production ........... 57 Trimethylolpropane Production ......... 57 4,4-Methylenedianiline Production ....... 59 Phthalic Anhydrine Production ......... 60 Use of Formaldehyde-Based Additive Solid Urea and Ureaform Fertilizer Production .................. 63 Miscellaneous Resin Applications ........ 67 Manufacturing Minor Products Using Formaldehyde as a Feedstock ................ 73 Miscellaneous Commercial/Consumer Uses of Formaldehyde ............... 75 Combustion Sources ............... 78 Oil Refining .................. 84 Asphaltic Concrete Production and Use ..... 92 Formaldehyde Production in the Atmosphere via Photo-Oxidation ............... 98 5. Source Test Procedures .............. 100 References ..................... 103 Appendix A-Calculations of Process Fugitive Emissions A-1 References for Appendix A .............. A-8 iii FIGURES Number Page 1 Common reactions of formaldehyde ........... 7 2 General reactions of formaldehyde .......... 9 3 Chemical use tree for formaldehyde .......... 12 4 Basic operations that may be used for formaldehyde production by the silver catalyst process ...... 14 5 Basic operations that may be used for formaldehyde production by the metal oxide process ........ 16 6 Basic operations that may be used in urea-formaldehyde and melamine-formaldehyde resin manufacture ..... 27 7 Basic operations that may be used fur phenol- formaldehyde resin manufacturing .......... 39 8 Basic operations that may be used for the production of polyacetal resins ................ 48 9 Basic operations that may be used in the production of hexamethylenetetramine ............... 51 10 Basic operations that may be used in the production of pentaerythritol ................... 54 11 Basic operations that may be used in the production of phthalic anhydride ................. 62 12 Basic flowsheet for a refinery ............ 85 13 Method 5 sampling train modified for the measurement of formaldehyde ................. 102 A-1 Process flow diagram for metal oxide process ..... A-3 A-2 Process flow diagram for silver catalyst process ... A-6 iv TABLES Number Page 1 Physical Properties of Monomeric Formaldehyde .... 6 2 Uncontrolled and Controlled Formaldehyde Emission Factors for a Hypothetical Formaldehyde Production Plant (Silver Catalyst Process) ........... 18 3 Uncontrolled and Controlled Formaldehyde Emission Factors for a Hypothetical Formaldehyde Production Plant (Metal Oxide Catalyst Process) ........ 20 4 Production of Formaldehyde .............. 24 5 Production of Urea-Formaidehyde Resins ........ 30 6 Production of Melamine-Formaldehyde Resins ...... 35 7 Production of Phenol-Formaldehyde Resins ....... 42 8 Production of Polyacetal Resins ........... 50 9 Production of Nexamethylenetetramine ......... 53 10 Production of Pentaerythritol ............ 56 11 Production of 1,4-Butanediol ............. 58 12 Production of 4,4-Methylenedianiline ......... 61 13 Production of Phthalic Anhydride ........... 64 14 Formaldehyde Emission Factors for Solid Urea Production 66 15 Standard Industrial Classification Codes for Manufacturing Processes Engaged in Resin Applications ....... 74 16 Manufacturers of Minor Products Using Formaldehyde as a Feedstock ................... 76 17 Formaldehyde Emissions From External Combustion Sources ................. 80 v TABLES (continued) Number Page 18 Formaldehyde Emissions From Stationary Internal Combustion Engines ................. 83 19 Total Aldehyde Emissions From Incineration and Open Burning ....................... 83 20 Formaldehyde Emissions From Transportation Sources . 86 21 Formaldehyde Emissions From Construction and Farm Equipment .................... 87 22 Formaldehyde Emissions From Petroleum Refining .... 91 23 Petroleum Refineries ................. 94 vi SECTION 1 PURPOSE OF DOCUMENT The EPA, States and local air pollution control agencies are becoming increasingly aware of the presence of substances in the ambient air that may be toxic at certain concentrations. This awareness, in turn, has led to attempts to identify source/receptor relationships for these substances and to develop control programs to regulate emissions. Unfortunately, very little information is available on the ambient air concentrations of these substances or on the sources that may be discharging them to the atmosphere. To assist groups interested in inventorying air emissions of various potentially toxic substances, EPA is preparing a series of documents such as this that compiles available information on sources and emissions of these substances. This document specifically deals with formaldehyde. Its intended audience includes Federal, State, and local air pollution personnel and others who are interested in locating potential emitters of formaldehyde and making gross estimates of air emissions therefrom. Because of the limited amount of data available on formaldehyde emissions, and since the configuration of many sources is not the same as those described herein, this document is best used as a primer to inform air pollution personnel about (1) the types of sources that may emit formaldehyde, (2) process variations and release points that may be expected within these sources, and (3) available emissions information indicating the potential for formaldehyde to be released into the air from each operation. The reader is strongly cautioned against using the emissions information contained in this document to try to develop an exact assessment of emissions from any particular facility. Since insufficient data are available to develop statistical estimates of the accuracy of these emission factors, no estimate can be made of the error that could result when these factors are used to calculate emissions from any given facility. It is possible, in some extreme cases, that orders-of-magnitude differences could result between actual and calculated emissions, depending on differences in source configurations, control equipment, and operating practices. Thus, in situations where an accurate assessment of formaldehyde emissions is necessary, source-specific information should be obtained to confirm 1 the existence of particular emitting operations, the types and effectiveness of control measures, and the impact of operating practices. A source test and/or material balance should be considered as the best means to determine air emissions directly from an operation. 2 SECTION 2 OVERVIEW OF DOCUMENT CONTENTS As noted in Section 1, the purpose of this document is to assist Federal, State, and local air pollution agencies and others who are interested in locating potential air emitters of formaldehyde and making gross estimates of air emissions from these sources. Because of the limited background data available, the information summarized in this document does not and should not be assumed to represent the source configuration or emissions associated with any particular facility. This section provides an overview of the contents of this document. It briefly outlines the nature, extent, and format of the material presented in the remaining sections of this report. Section 3 of this document provides a brief summary of the physical and chemical characteristics of formaldehyde, its commonly occurring forms, and an overview of its production and uses. A chemical use tree summarizes the quantities of formaldehyde consumed in various end use categories in the United States. This background section may be useful to someone who needs to develop a general perspective on the nature of the substance and where it is manufactured and consumed. Section 4 of this document focuses on major industrial source categories that may discharge formaldehyde air emissions. This section discusses the manufacture of formaldehyde, its use as an industrial feedstock, applications of resins produced from formaldehyde, and formaldehyde production
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