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Acid Plant Database  October 5, 2023

Owner Mosaic Company
Mosaic Phosphate Company

Mosaic-Logo.gif (2654 bytes)

Location 7250 Highway 44
Uncle Sam
St. James Parish
USA  70792 
Background In the early 1900s Thomas C. Meadows, an entrepreneur in Tennessee's phosphate mining business, formed the United States Agricultural Corporation. The company was established to provide basic fertilizer nutrients to U.S. growers.
1909 - Meadows and his brother-in-law, Oscar L. Dortch, teamed with Waldemar A. Schmidtmann whose holdings included Kaliwerke Sollstedt - a thriving potash mine in Germany. The three acquired the Schmidtmann holdings in the potash mine and formed the International Agricultural Corporation in New York.
1942 - Company moved its headquarters to the Chicago area and changed its name to International Minerals & Chemical Corporation
1988 - Initial public offering of the fertilizer assets of International Minerals & Chemical Corporation created a new public company called IMC Fertilizer Group
1993 - IMC Global entered into a joint venture that launched IMC Phosphates Company M.P. (originally known as IMC-Agrico Company), a phosphate mining and fertilizer production company in Florida and Louisiana
1994 - Company name changed to IMC Global Inc. to better reflect the worldwide scope of the corporations operations
1997 - IMC Global merged with Freeport-McMoRan
Formerly Agrico Chemical Company
Formerly IMC-Agrico (2004)
Website www.mosaicco.com
Plant Uncle Sam Plant
A - Train D - Train E - Train

30º 2' 20" N, 90º 49' 45" W

30º 2' 15" N, 90º 49' 44" W

30º 2' 14" N, 90º 49' 47" W

Type of Plant Sulphur Burning Sulphur Burning Sulphur Burning
Gas Source Elemental Sulphur Elemental Sulphur Elemental Sulphur
Plant Capacity 1500 MTPD 1500 MTPD 2900 MTPD
SA/DA SA 3/1 DA 3/1 DA
Status Operating Operating Operating
Year Built 1968 1974 1992
Technology  Chemico  Chemico MECS
Contractor - - -

2004 - Original absorber tower replaced with MECS alloy tower
2009 - Original sulphur furnace replaced
        - Original converter replaced, new 38 ft dia. MECS stainless steel converter

2011 - Cansolv tailgas scrubber unit installed

2008 - Inter and final absorber tower replaced with MECS alloy towers

B and C Trains (1500 MTPD each) were constructed at the same time as A-Train but were shutdown and demolished in 1992.

In response to then-current reduced market demand, IMC Phosphates suspended production at its Taft facility in July 1999 and suspended phosphoric acid production at its Faustina facility in November 1999.  From January 2001 until August 2001, IMC Phosphates temporarily shut down its Uncle Sam phosphoric acid production as well as its Faustina DAP and GMAP production.  The Taft facility and Faustina's phosphoric acid production facilities remain temporarily idled.

General The Uncle Sam plant was named for the Uncle Sam Plantation which was once located on the land now occupied by the plant.
References -
News September 12, 2023 - In Louisiana, an unexpected local utility power interruption at the end of August resulted in damage to the largest sulfuric acid plant at Louisiana's Uncle Sam facility. Repairs to the complex, which operates at a production rate of 15,000 finished product tonnes per week, are anticipated to be completed by the end of October.

December 10, 2019
- Mosaic Co. is restarting its idled fertilizer production facilities in St. James Parish and officials hope they will be fully operational by Monday.  Spokeswoman Callie Neslund said all employees furloughed during the two-month idling returned to work last week, but many of them are undergoing standard safety training following the extended break.  The company halted production in St. James Parish on Oct. 1 and furloughed more than 370 employees due to an oversupply of the agriculture fertilizer that Mosaic makes along the Mississippi River, company officials said then.  Though a handful of employees remained during the furlough for maintenance, the idling affected both Mosaic operations in St. James — the Uncle Sam and Faustina facilities straddling either side of the river.  Neslund said the fall season was not as good as the company hoped, but the idling achieved a balance of customer demand with the company's excess inventory.  "We hope to be fully operational by the 16th, but in the interim, all of the employees have returned to full-time employment," Neslund said.  She said the company began the multiday process of restarting the complex on Thursday and had previously begun receiving shipments in preparation for the restart.  During the plant idling, furloughed employees received at least 70% of their pay, plus all key benefits.  The slowdown came as the company was responding to a slow shifting of its massive waste gypsum pile at the east bank of the Uncle Sam facility near Convent, though company officials said the plant idling was related to market conditions.  The movement of the waste pile, which is about 185 feet tall and has its own nighttime warning lights for aircraft, had raised worries early this year from state and federal regulators concerned about the integrity of a large lake inside the pile. The lake holds hundreds of millions of gallons of acidic and radioactive process water.  Regulators and the company now say the risk of a catastrophic failure and release of the water is minimal.  The movement of parts of the pile's north wall and the earth deep beneath that wall have slowed significantly after a series of emergency measures. The movement went from more than a half-inch per day to one-tenth to one-hundredth of an inch per day, on average, state reports show.  A halt in production affects the company's ability to manage the supply of the process water on site, company officials have previously said. Rainfall expands that supply while continued fertilizer production causes the water to evaporate.  Company officials said at the time of the furlough that they had spare water storage capacity and other efforts underway to reduce process water levels so they could manage the water during the production halt.

September 17. 2019
- Mosaic Co. is idling its Louisiana phosphates operations in St. James, cutting production by about 500,000 tons this year, as imports into the country have pushed down prices.  The move is intended to speed up how fast Mosaic can empty its inventories, though the company expects “a more balanced global supply-and-demand picture to emerge by 2020.”  Prices of the fertilizer ingredient have been under pressure since late 2018 as demand remains weak and capacity expansions in Morocco and Saudi Arabia have increased output and exports, Reuters reports.  “Phosphate prices have declined further through the summer, with excess imports continuing to enter the U.S. on top of high channel inventories,” President and CEO Joc O’Rourke said in a statement. “We expect our move to idle production to tighten supply and rebalance the market. Mosaic will prioritize shipments to meet key customer needs through the idling period.”   The company will also initiate $250 million in stock repurchases under its existing share repurchase authorization, which has $850 million of remaining capacity, according to the announcement.  Mosaic operates its Faustina and Uncle Sam facilities in St. James Parish. At the Uncle Sam Facility, a turbo generator harnesses excess heat from sulfuric acid production. The cogeneration process allows Mosaic to harness “clean and green” energy. Uncle Sam produces phosphoric acid, which is then shipped across the river to the company’s Faustina facility, producing ammonia to make MAP, DAP and other products.

October 1, 2015
- EPA and the U.S. Department of Justice announced a settlement with Mosaic Fertilizer, LLC that will ensure the proper treatment, storage, and disposal of an estimated 60 billion pounds of hazardous waste at six Mosaic facilities in Florida and two in Louisiana. The settlement resolves a series of alleged violations by Mosaic, one of the world’s largest fertilizer manufacturers, of the federal Resource Conservation and Recovery Act (RCRA), which provides universal guidelines for how hazardous waste must be stored, handled and disposed. The 60 billion pounds of hazardous waste addressed in this case is the largest amount ever covered by a federal or state RCRA settlement and will ensure that wastewater at Mosaic’s facilities is properly managed and does not pose a threat to groundwater resources. 
The 60 billion pounds of hazardous waste is based on the combined amount of corrosive wastewaters that will be treated at terminal closure of the facilities. Mosaic is one of the fertilizers industry’s best performers in its ability to reduce large volumes of corrosive wastewater in its phosphogypsum stack systems. In addition to recovering valuable phosphate and other compounds, Mosaic is able to reduce terminal closure costs while ensuring that its phosphogypsum stack systems are operated in an environmentally safe manner.  Four Mosaic facilities (New Wales, Bartow, Riverview in Florida and Uncle Sam in Louisiana) will continue to produce phosphoric acid and actively utilize its phosphogypsum stack systems. Mosaic is in the closure process for the Green Bay Complex and South Pierce facility in Florida, and the Faustina facility in Louisiana. However, Faustina will continue to manufacture ammoniated fertilizer. Mosaic operated a small sulfuric acid plant at the Mulberry facility in Florida for a short time. The Mulberry sulfuric acid plant was closed around 2008 and there are no obligations regarding this site in this settlement.  Mosaic has been making major improvements at all its facilities and completed several notable projects: installation of state-of-the-art elementary neutralization units to improve the management of sulfuric acid waste streams, upgrading air scrubbers at its granulation and phosphoric acid plants, and installing automated spill and leak detection systems. All of these projects have been closely monitored by Florida Department of Environmental Protection, and Louisiana Department of Environmental Protection, who provided valuable expertise at each step of the process.

May 10, 2011
- The Mosaic Company today announced it will temporarily shut down its Louisiana operations due to the impact of the Mississippi River flooding on its electrical power supplies. Operations will resume when river water levels recede and conditions permit.  The Company also noted that its ammonia plant at this location is temporarily idled for repairs following a recent incident.  Mosaic's Louisiana operations include Faustina, which produces diammonium phosphate and ammonia, and its Uncle Sam facility, which produces phosphoric, sulfuric and fluosilicic acid.  These matters are not expected to have a material impact on Mosaic's operations or financial results.


November 16, 2009 - The Mosaic Company (Mosaic) has contracted Cansolv Technologies Inc (Cansolv) an affiliate of Shell Global Solutions International B.V., to supply a modular CANSOLV SO2 Scrubbing System. The modular plant will capture SO2 from sulfuric acid plant tail gas at Mosaic’s Uncle Sam fertilizer production facility in Louisiana, USA.   The CANSOLV SO2 Scrubbing System will be a key factor in enabling Mosaic to meet the SO2 reductions Mosaic has agreed to implement with its regulators. It is also the first regenerable technology of its kind to be installed in the fertilizer industry in the United States.  The project award follows the successful implementation of the CANSOLV SO2 Scrubbing System in a wide range of industrial sectors with operating plants in the petrochemical, metallurgical and power industries.  Mosaic has chosen to procure a pre-fabricated modular plant following an engineering study that demonstrated the cost-effectiveness of this approach.  The expected delivery date of the modular plant is September 2010.  The CANSOLV SO2 Scrubbing System is a new benchmark for environmental performance of sulfuric acid plants in the fertilizer industry. The technology will enable the Mosaic facility to meet SO2 emissions of 1 lb SO2/ton acid, while generating minimal liquid effluent. The Cansolv patented technology uses a regenerable amine to selectively absorb sulfur dioxide from the tail gas stream and recycles the pure SO2 by-product to the acid plant, maximizing productivity and minimizing liquid effluent.


October 10, 2009 - Mosaic Fertilizer agreed this week to give up its permit for a now-closed sulfuric acid production plant in Mulberry in partial settlement of a Clean Air Act action filed in federal court in New Orleans.   It did not, as the Associated Press erroneously reported, agree to close its Bartow chemical plant, which remains in operation.  The confusion, according to Russell Schweiss, public affairs manager for Mosaic, came from a reference to the Mulberry plant as being “near Bartow.”  Mosaic shut down the Mulberry plant in 2008, Schweiss said.  Mosaic, which has its corporate headquarters in Plymouth, Minn., is the last phosphate company still operating in Polk County.  In the settlement, the company agreed to spend about $30 million to improve air pollution controls at its sulfuric acid plant near Baton Rouge, La., as well as to give up its permit for the Mulberry plant.  Since that plant is closed, the settlement has no effect on any Mosaic opertions in Florida, Schweiss said.  He said the upgrades at the Louisiana plant will include state-of-the-art scrubbers to capture sulfur dioxide emissions.   The agreement also requires Mosaic to pay a $2.4 million civil penalty.   Sulfur dioxide is emitted in the production of sulfuric acid, and in sufficient concentrations, can cause respiratory problems.


October 5, 2009 - Plymouth-based fertilizer giant Mosaic reported sharply lower profits for the first quarter amid a global sales slowdown of crop nutrients.  In a release issued after trading closed Monday, the company reported sales of $1.46 billion, or 66 percent below last year's first quarter sales of $4.32 billion. Earnings of $100.6 million for the quarter ending Aug. 31 were 92 percent below last year's $1.18 billion and amounted to 23 cents per share.  Analysts had expected earnings of 35 cents per share on sales of $1.54 billion.  Sharp increases in fertilizer costs beginning last year, along with falling prices for some key agriculture commodities and the global recession, have thrown fertilizer sales into a tailspin. Mosaic's industry rival, PotashCorp. of Saskatchewan, Inc., has scaled back its financial guidance several times this year.   Mosaic, which produces fertilizer ingredients potash and phosphate, earlier this year declined to issue guidance "until market conditions normalize" on significant aspects of its business, including potash sales volumes and selling price.   Cargill, the agribusiness titan and majority owner of Mosaic, warned in August that earnings had dropped at Mosaic. That same month, Mosaic officials said potash sales had fallen 35 to 40 percent, and phosphate sales were off 15 to 20 percent.  The company's long-term outlook remains positive because global demand for food, and thus the fertilizer needed to grow it, remains strong and rising. Projections of both population and calorie consumption show that farmers around the world must sharply increase their production to feed the planet.  "Phosphate fundamentals have improved," said James T. Prokopanko, company president and CEO. "The potash market is evolving and we expect strong demand in calendar year 2010 for both nutrients."


October 5, 2009 - A Minnesota-based company accused of violating the Clean Air Act has agreed to spend about $30 million to improve air pollution controls at its sulfuric acid production plant in Louisiana.  A settlement agreement filed Monday in a New Orleans federal court also calls for Mosaic Fertilizer of Plymouth, Minnesota, to pay a $2.4 million civil penalty.  The Justice Department and U.S. Environmental Protection Agency says Mosaic agreed to install equipment that will limit sulfur dioxide emissions at its plant in Uncle Sam, Louisiana, and will permanently cease sulfuric acid production at its plant in Bartow, Florida.

MTPD - Metric Tonne per Day           STPD - Short Ton per Day
MTPA - Metric Tonne per Annum      STPA - Short Ton per Annum
SA - Single Absorption
DA - Double Absorption

* Coordinates can be used to locate plant on Google Earth