Ferrous Sulfate Supply Chain - Executive Summary Ferrous Sulfate Direct Use Chemical p-ecursor Chemical FeS04 (liquid, solid) Inputs to Manufacturing Process: Sulfuric Acid Iron Oxides Iron Derivative Water Treatment Chemicals: Ferric Sulfate ^ % of Total Domestic Consumption Attributed to Water Sector: Approximately 30% fos Understanding Chemical Supply Chains Map of Suppliers & Manufacturers Product Family: Iron Sulfur CAS No.: 7720-78-7 2 Shelf Life: 12+ Months — RISK OF SUPPLY DISRUPTION (Assessed in 2022) RISK RATING: Low I Alii K/IoWsN.. RISK DRIVERS Production of ferrous sulfate depends on the steel industry and production of sulfuric acid to produce manufacturing in- puts. Fluctuations in demand in the steel industry may impact production and price of ferrous sulfate. RISK PARAMETERS Criticality: High. Essential for coagulation and production of water treatment chemicals. Likelihood: Low. Previous price increases, but no supply disrup- tions. Vulnerability: Low. Distributed domestic manufacturing and supply. MANUFACTURING PROCESS Iron Oxides Iron Ferrous Sulfate Sulfuric Acid Input End Use Water Treatment Applications • Coagulation • Water treatment chemical production Other Applications Fertilizer Animal feed Pharmaceuticals Iron fortification of foods DOMESTIC PRODUCTION AND CONSUMPTION, AND INTERNATIONAL TRADE Domestic Manufacturing Locations (2015): 13, distributed throughout the U.S. (^) International Trade (2019) Primary Trading Partner (Imports): China Primary Trading Partner (Exports): Canada Domestic Production and Consumption Total domestic manufacturing of ferrous sulfate reported under the TSCA CDR was approximately 18 M kg in 2015. Significantly, several domestic manufacturers of ferrous sulfate did not report production. Due to this data gap and differences in reporting between production and trade data, U.S. consumption of ferrous sulfate could not be estimated. &EPA ------- Ferrous Sulfate Supply Chain - Full Profile Product Description Ferrous sulfate (FeS04), an iron salt, is widely used in food, agriculture and chemical production. In water treatment it is a commonly used coagulant. Ferrous sulfate is primarily produced as a byproduct of steel pickling, a process that relies on iron oxides and sulfuric acid. Use in Water Treatment Ferrous sulfate is used as a coagulant in both wastewater and drinking water treatment (AWWA, 2018). Use as a Precursor to Other Water Treatment Chemicals Ferrous sulfate is used to manufacture ferric sulfate. Other Applications Ferrous sulfate is used as a component of fertilizer, an additive in animal feed, pharmaceuticals, iron fortification of foods, and as a pigment (NCBI, 2021). Primary Industrial Consumers Historically, use in fertilizer and as an animal feed additive have been the primary domestic uses of ferrous sulfate. Water treatment is a significant use of ferrous sulfate, historically accounting for up to 30% of domestic consumption (NCBI, 2021). Manufacturing, Transport, & Storage Manufacturing Process Ferrous sulfate can be produced with a number of starting materials. Iron, ferrous oxide, and sulfuric acid are the primary materials used to produce ferrous sulfate. Ilmenite, the raw material used to produce titanium dioxide, can also be used but is a less common source of iron oxides in North America. The method most commonly used in North America utilizes a reaction of spent steel pickling liquors or scrap iron with sulfuric acid. Pickling of steel removes the surface iron oxide from steel by immersion in a bath containing either a sulfuric or hydrochloric acid solution. When sulfuric acid is used, mixed oxides in the oxidation layer of the steel as well as the underlying iron react with the sulfuric acid to form ferrous sulfate as shown in Figure 1. Ferrous sulfate is then filtered and crystallized to complete the production (Barben Analytical, 2015; de Buzin et al., 2014; EPA, 2001). Reaction of Mixed Iron Oxides (Fe203, Fe304, and FeO) and Steel with Sulfuric Acid Iron Oxide + Steel + Sulfuric Acid —> Ferrous Sulfate + Water Fe203 + Fe + 3H2SO4 —> 3FeS04 + 3H2O Iron Oxide + Steel + Sulfuric Acid —> Ferrous Sulfate + Water Fe304 + Fe + 4H2S04 -> 4FeS04 + 4H20 Iron Oxide + Sulfuric Acid —> Ferrous Sulfate + Water FeO + H2SO4 -> FeS04 + H2O Iron + Sulfuric Acid —> Ferrous Sulfate + Hydrogen Fe + H2SO4 —> FeS04 + H2 Figure 1. Chemical Equation for the Reaction to Manufacture Ferrous Sulfate EPA 817-F-22-027 | December 2022 c/EPA ------- Ferrous Sulfate Supply Chain - Full Profile Production as a byproduct of the manufacture of titanium dioxide results from the process to remove the iron oxide impurities present in low-grade ilmenite. Acid leaching processes include hydrochloric acid or sulfuric acid leaching. Prior to leaching, pretreatment includes reduction or sequential oxidation and reduction. In the sulfate process, the ilmenite is then digested with sulfuric acid, yielding a titanium sulfate solution which is hydrolyzed and precipitated to form titanium dioxide and a waste stream of ferrous sulfate (EPA, 2001). Product Transport Ferrous sulfate is transported by many means including truck, rail, barge, and ship. Storage and Shelf Life Ferrous sulfate is stable under recommended storage conditions, but degrades when exposed to direct sun and heat. When stored properly, ferrous sulfate can have a shelf life greater than twelve months, though stability may depend upon many factors (Affinity Chemical, 2019). Domestic Production & Consumption Domestic Production Production data was collected from the 2016 EPA Toxic Substances Control Act (TSCA) Chemical Data Reporting (CDR) for the year 20151, while trade data was collected from the U.S. International Trade Commission (USITC) Dataweb, as shown in Table 1. While production data is specific to ferrous sulfate, trade data includes ferrous sulfate as part of a broader trade category of metal sulfates. For imports, the trade category is specific to iron sulfates, while the export trade category includes ferrous sulfate among metal sulfates, 'not elsewhere specified' (NES). Table 1. Ferrous Sulfate Production and Trade Data Sources Production and Trade Data Category Data Source Identifier Description Domestic Production 2016 EPA CDR CAS No.: 7720-78-7 Ferrous Sulfate Imports and Exports U.S. International Trade Commission HTS Code (Imports): 2833.29.2000 HS Code (Exports): 2833.29 Iron Sulfates Metal Sulfates, NES Total U.S. domestic manufacturing of ferrous sulfate reported under the CDR was approximately 18 million kilograms (M kg) in 2015; however, several manufacturers claimed confidential business information and did not report production volumes to EPA. Domestic commercial manufacture of ferrous sulfate takes place at a limited number of facilities throughout the contiguous U.S. Primary producers include USALCO (formerly Altivia Chemicals), Kemira Water Solutions, and Keystone Steel and Charter Steel (steel manufacturer). Most ferrous sulfate production facilities are associated with the steel industry. The number of domestic manufacturing locations shown in Figure 2 represents operating facilities as of 2015 (EPA, 2016). Supply of NSF/ANSI Standard 60 certified ferrous sulfate for use in drinking water treatment is limited to a few locations throughout the U.S. (NSF International, 2021). For a more current listing of manufacturing locations and supplier locations, visit the U.S. Environmental Protection Agency's (EPA's) Chemical Locator Tool (EPA, 2022a). 1 Although 2019 CDR data is available, reporting is less complete when compared to 2015 data due to an increase in the number of companies claiming confidential business information (CBI). In both instances, CBI may account for a significant volume of ferrous sulfate produced that is not reflected in CDR reporting. &EPA ------- Ferrous Sulfate Supply Chain - Full Profile Figure 2. Domestic Supply and Manufacturing of Ferrous Sulfate Domestic Consumption Due to differences in reporting for production and trade data, as well as the significant number of producers that did not report production data under the CDR, U.S. consumption of ferrous sulfate could not be estimated. Domestic production of ferrous sulfate may represent a small quantity when compared to the import and export volume for the category of sulfates including ferrous sulfate. Trade & Tariffs Worldwide Trade Worldwide import and export data for ferrous sulfate are reported through the World Bank's World Integrated Trade Solutions (WITS), as a category representing metal sulfates, NES. In 2021, the U.S. ranked 18th worldwide in total exports and second in total imports of metal sulfates, NES. In 2021, Germany ranked first worldwide in total exports and imports (WITS, 2022), as shown in Table 2. Import and export data specific to ferrous sulfate is unavailable from the referenced sources. &EPA ------- Ferrous Sulfate Supply Chain - Full Profile Table 2. WITS Worldwide Export and Import of Metal Sulfates, NES, Including Ferrous Sulfate in 2021 2021 Worldwide Trade Metal Sulfates, NES (HS Code 2833.29) Top 5 Worldwide Exporters Top 5 Worldwide Importers Germany 836 M kg Germany 348 M kg China 636 M kg United States 267 M kg Poland 257 M kg Austria 144 M kg Spain 129 M kg United Kingdom 99 M kg Slovenia 119 M kg Sweden 93 M kg Domestic Imports and Exports Domestic imports and export data are reported by USITC in categories for metal sulfates. For imports, the trade category is specific to iron sulfates, while the export trade category includes metal sulfates, NES. Figure 3 summarizes imports for consumption2 and domestic exports3 between 2015 and 2020. During this period, the overall quantity of imports varied between 62 and 94 M kg. The quantity of exports was consistently much smaller than the quantity of imports. Over this five-year period, Canada was the primary recipient of domestic exports while China replaced Canada and Spain as the primary source of imports (USITC, 2021). 120 100 80 J? 60 IS) ¦2 40 s 20 Domestic Trade of Iron Sulfates (Imports) and Metal Sulfates, NES (Exports) HS Code 2833.29 .. I. I. I. I. 2015 2016 2017 2018 2019 2020 ¦ Imports from China ¦ Exports to Canada ¦ Imports from Spain I Exports to Mexico I Imports from Other Countries Exports to Other Countries Figure 3. USITC Domestic Import and Export of Iron Sulfates, including Ferrous Sulfate between 2015 and 2020 2 Imports for consumption are a subset of general imports, representing the total amount cleared through customs and entering consumption channels, not anticipated to be reshipped to foreign points, but may include some reexports. 3 Domestic exports are a subset of total exports, representing export of domestic merchandise which are produced or manufactured in the U.S. and commodities of foreign origin which have been changed in the U.S. &EPA ------- Ferrous Sulfate Supply Chain - Full Profile Tariffs There is no general duty for import of ferrous sulfate, however there is an additional 25% duty for imports from China (USITC, 2022), as summarized in Table 3. Table 3. 2021 Domestic Tariff Schedule for Iron Sulfates, including Ferrous Sulfate HTS Number General Duty Additional Duty - China (Section 301 Tariff List) Special Duty 2833.29.2000 None 25% None Market History & Risk Evaluation History of Shortages The production of ferrous sulfate in North America is heavily reliant on the steel industry and availability of sulfuric acid. Economic slowdowns and a drop in domestic steel manufacturing along with greater recycling of steel pickling liquor and fluctuating prices for sulfuric acid have been known to impact the availability of ferrous sulfate. Risk Evaluation The complete risk assessment methodology is described in Understanding Water Treatment Chemical Supply Chains and the Risk of Disruptions (EPA, 2022b). The risk rating is calculated as the product of the following three risk parameters: Risk = Criticality x Likelihood x Vulnerability Criticality Measure of the importance of a chemical to the water sector Likelihood Measure of the probability that the chemical will experience a supply disruption in the future, which is estimated based on past occurrence of supply disruptions Vulnerability Measure of the market dynamics that make a chemical market more or less resilient to supply disruptions The individual parameter rating is based on evaluation of one or more attributes of the chemical or its supply chain. The ratings and drivers for these three risk parameters are shown below in Table 4. &EPA ------- Ferrous Sulfate Supply Chain - Full Profile Table 4. Supply Chain Risk Evaluation for Ferrous Sulfate Risk Parameter Ratings and Drivers 1 1 i ICriticality High 1 Likelihood Low 1 Vulnerability Low 1 Ferrous sulfate is an essential water treatment chemical. It is widely used as a coagulant and serves as a precursor in manufacturing ferric sulfate. The water sector has experienced price fluctuations in the past, but has not experienced supply chain disruptions between 2000 and 2022. Strong domestic manufacturing capabilities and a distributed manufacturing base provide some resilience to supply disruptions. However, the reliance on the steel industry may increase vulnerability. Risk Rating: Low A11 l Xe-Low Modern 'e/> t k % 1 1 References Affinity Chemical, 2019. Safety Data Sheet for Ferrous Sulfate Solution, retrieved from https://www.affinitychemical.com/content/uploads/2019/05/AffinityChemical-FerrousSDSVl.pdf American Waterworks Association (AWWA), 2018. B402 Ferrous Sulfate. Denver, CO: American Water Works Association. Barben Analytical, 2015. Application Note, Titanium Dioxide - Sulfate Process, retrieved from https://www.barbenanalytical.com/applications/application-notes de Buzin, P.J.W.K., Viganico, E.M., Silva, R.D.A., Heck, N.Z., Schneider, I.A.H. and Menezes, J.C.S.S., 2014. Production of Ferrous Sulfate From Steelmaking Mill Scale. International Journal of Scientific & Engineering Research, 5(4):353-359. EPA, 2001. Final Titanium Dioxide Listing Background Document for the Inorganic Chemical Listing Determination, retrieved from https://archive.epa.gov/epawaste/hazard/web/pdf/tio2-bd.pdf EPA, 2016. 2016 TSCA Chemical Data Reporting, retrieved from https://www.epa.gov/chemical-data- reporting/access-cdr-data#2016 EPA, 2022a. Chemical Suppliers and Manufacturers Locator Tool, retrieved from https://www.epa.gov/waterutilityresponse/chemical-suppliers-and-manufacturers-locator-tool EPA, 2022b. Understanding Water Treatment Chemical Supply Chains and the Risk of Disruptions, retrieved from https://www.epa.gov/waterutilityresponse/risk-disruptions-supply-water-treatment-chemicals National Center for Biotechnology Information (NCBI), 2021. PubChem Compound Summary for CID 24393, Ferrous Sulfate, retrieved from https://pubchem.ncbi.nlm.nih.gov/compound/24393 NSF International, 2021. Search for NSF Certified Drinking Water Treatment Chemicals, retrieved from https://info.nsf.org/Certified/PwsChemicals/ &EPA ------- Ferrous Sulfate Supply Chain - Full Profile U.S. International Trade Commission, 2021. USITC DataWeb, retrieved from https://dataweb.usitc.gov/ U.S. International Trade Commission (USITC), 2022. Harmonized Tariff Schedule (HTS) search, retrieved from https://hts.usitc.gov/ World Integrated Trade Solutions, 2022. Trade Statistics by Product (HS 6-digit), retrieved from https://wits.worldbank.org/trade/country-byhs6product.aspx?lang=en#void 7 &EPA ------- |