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The facility has four "continuous process" manufacturing plants to produce formaldehyde. The three older formaldehyde plants (1956, 1963, and 1965) use silver as a catalyst in their reaction process and are often referred to as the "silver plants". The formaldehyde product is produced by reacting methanol with air using a silver catalyst and then scrubbing the resulting gas with water. The emissions of formaldehyde, methanol, and hydrogen gas are controlled using two tail gas-fired boilers. Tail gas-fired boiler no. 1 (12.4 million Btu per hour) is used to control the emissions from formaldehyde plants 1 and 2, while tail gas-fired boiler no. 2 (20.9 million Btu per hour) is used to control the emissions from formaldehyde plant 3. Except for start-up, supplemental fuel is not required for the tail gas-fired boilers. The formaldehyde plants are subject to the requirements of the Hazardous Organic NESHAP (HON). The "newer" formaldehyde manufacturing plant (1989) uses molybdenum oxide as a catalyst and is often referred to as the "mixed oxide" or "MO" plant. The emissions from this plant are controlled using a catalytic oxidizer.
The facility currently has three batch reactors that are used to produce resins. Two of the reactors are used to produce urea-formaldehyde resin (reactor ES-2 with 17,000 gallon capacity; reactor ES-3 with 15,000 gallon capacity) and one reactor that is used to produce phenol-formaldehyde resin (reactor ES-4 with 18,000 gallon capacity). A new scrubber controls the emissions of all three reactors. The new scrubber is expected to allow the facility to meet the required 83 percent control requirement of the resins MACT.
The hexamethylenetetramine manufacturing plant (constructed in 1981) is usually referred to as the hexamine plant. The process uses ammonia and formaldehyde as raw materials and results in a solid product that is loaded into bags and shipped to other Borden facilities where it is used to cure resins. Several years ago this plant produced very high methanol emissions. However, the plant was modified to include an aqueous reverse osmosis system that significantly reduced the large vapor losses from the cooling tower. The methanol is introduced into the process as a component of the formaldehyde solution. Small amounts of methanol are added to formaldehyde to act as an inhibitor and prevent the formation of para-formaldehyde. The hexamine plant emissions are controlled using an impingement plate-type wet scrubber.
Each boiler is rated at 20.9 mmBtu/hr and fires natural gas/No. 4 fuel oil/No. 5 fuel oil/No. 6 fuel oil.