DRAFT PERMIT REVIEW SUMMARY

Permit Writer:	Thomas Parker 	Date:	August 5, 2026

Company Name:	Polychemie Inc.

Facility Location:	Port Bienville Industrial Park, Road Drive

Source Number:	1000-00042

County: 		Hancock

FACILITY DESCRIPTION

Polychemie Inc. (Polychemie) owns and operates a water treatment polymer and monomer production facility located in Pearlington, MS. The facility is classified under SIC Code 2899 (Chemicals and Chemical Preparations, Not Elsewhere Classified) and NAICS Code 325998 (All Other Miscellaneous Chemical Product and Preparation Manufacturing). Polychemie is a source of Particulate Matter (PM), PM less than 10 microns (µm) (PM10), PM less than 2.5 µm (PM2.5), Sulfur Dioxide (SO2), Carbon Monoxide (CO), Volatile Organic Compounds (VOCs), and Hazardous Air Pollutants (HAPs). The emission points for the facility’s modified emission points are shown in the table below.

Emission
Point	Facility ID	Description	
AA-001	B-100	25.1 MMBtu/hr Natural Gas-Fired Boiler	
AA-002	B-101	13.4 MMBtu/hr Natural Gas-Fired Boiler	
AA-004	-	755 HP Diesel Fired Emergency Generator	
AA-005	B-103	25.1 MMBtu/hr Natural Gas-Fired Boiler	
AA-050	P-1A through       P-1F	DADMAC Production Lines
Includes the following equipment:
Monomer Reactors (R801 through R-804, R-809, R-810)
Slurry Tanks (V-801, V-802, V-809)
Centrifuges (C-801 through C-803, and C-810)
Centrifuge Receivers (V-C801 through V-C803)
Monomer Vessels (V-803)
Organics Vessel (V-804)
Liquid-Liquid Centrifuges (LS-803, LS-804, and LS-805)
AOH/Water Vessel (V-805)
Polymer Reactors (R-501, R-502, R-805 through R-808)
Initiator Make-ups (V-R805 through V-R808)
Polymer Blend Vessels (V-501, V-502, V-806 through V-808)
Gas Sampling Unit on Distillate Line	
AA-100	P-2A            through                 P-2D	Polyamine Process Lines
Includes the following equipment:
Reactors (R-901 through R-904)
Blend Vessels (V-901 through V-904)	
AA-401	EDC-NH3	Ethylene Dichloride (EDC)-Ammonia Polyamine Production Line
Includes the following equipment:
Reactor (R-401)
Receiver Vessel (V-401)
Distillation Column (D-401)
Centrifuge (C-401)	
AA-530	LQ10-SAS	SAS Monomer Production/Neutralization
Emissions vent to Emission Point AC-510 when producing SAS Polymer	
	LQ10-MAS	MAS Polymer Production/Neutralization 
Emissions vent to Emission Point AC-511 when producing MAS Polymer	
AB-100	TO-100	Thermal Oxidizer
Controls emissions from the DADMAC Process Lines (AA-050), the EDC-Ammonia process (AA-401), and the Hazardous waste storage tanks (AD-830 and AD-831).  Emissions from the thermal oxidizer are routed to the packed tower scrubber S-TO100 (AC-100).	
AB-200	TO-200	Thermal Oxidizer
Controls emissions from DADMAC Process Lines (AA-050) and the EDC Ammonia Process (AA-401, AD-830, and AD-831).  Emissions from the thermal oxidizer are routed to the packed tower scrubber S-TO200 (AC-200).	
AC-100	S-TO100	Packed Tower Scrubber
Controls emissions from the Thermal Oxidizer (AB-100)	
AC-101	SC-901	Venturi, Packed Tower Scrubber with mist eliminator
Controls emissions from the Polyamine process (AA-100)	
AC-200	S-TO200	Venturi, Packed Tower Scrubber with mist eliminator
Controls emissions from Thermal Oxidizer (AB-200)	
AC-400	SC-T6	Venturi, Packed Tower Scrubber with mist eliminator
Controls emissions from Hydrochloric Acid Tank (AD-006)	
AC-510	LQ10-SC1	Venturi, Packed Tower Scrubber
Controls emissions from SAS Monomer Production (AA-530), SAS/MAS Storage Tank (AD-602), and SAS Monomer/SAS Shutdown/Wash Water Tank (AD-606), which may also vent to the atmosphere	
AC-511	LQ10-SC2	Venturi, Packed Tower Scrubber
Controls emissions from MAS Polymer Production/Neutralization (AA-530) and maleic anhydride storage tank (AD-601), which may also vent to the atmosphere	
AC-520	-	SAS/MAS Bulk/Non-Bulk Loading Operations 
Emissions may vent directly to atmosphere, directly to scrubber (Emission Point AC-510), or indirectly to Emission Point AC-510 via vapor balance with SAS process (Emission Point AA-530) or storage tank (Emission Point AD-602)	
AD-001	T-1	Allyl Chloride Tank: 35,000-gallon pressurized tank	
AD-002	T-2	Allyl Chloride Tank: 35,000-gallon pressurized tank	
AD-003	T-3	Dimethylamine Tank: 35,000-gallon pressurized tank	
AD-004	T-4	Dimethylamine Tank: 37,628-gallon pressurized tank	
AD-006	T-6	Hydrochloric Acid Tank: 6,000-gallon fixed roof tank venting to optional Scrubber (AC-400)	
AD-011	T-11	Epichlorohydrin Tank: 35,000-gallon fixed roof tank	
AD-013	T-13	Ethylenediamine 8,000-gallon fixed roof tank	
AD-014	T-14	Sodium Bisulfite Tank, 40%: 10,000-gallon fixed roof tank	
AD-015	T-15	Recycle Water/Potassium Hydroxide Solution (45%) Tank: 6,000-gallon fixed roof tank	
AD-018	T-18	Ethylene Dichloride (EDC) Tank: 35,000-gallon pressurized tank	
AD-019	T-19	Aqueous Ammonia, 30% Tank: 17,460-gallon pressurized tank	
AD-020	T-20	Weak Ammonia Tank: 6,000-gallon fixed roof tank	
AD-021	T-21	Polyamine Tank: 7,044-gallon fixed roof tank	
AD-032	T-32	Dimethylamine Tank: 37,628-gallon pressurized tank 	
AD-036	T-36	Ethylenediamine Tank: 10,000-gallon fixed roof tank	
AD-105	T-105	Glycol/Water Tank: 7,000-gallon fixed roof tank	
AD-106	T-106 through     T-112,           T-120	Recycle Water Tanks: 8 fixed roof tanks ranging from 1,000 gallons to 12,000 gallons	
AD-113	T-113	Wastewater Check Tank: 6,000-gallon fixed roof tank	
AD-124	T-124	Diesel Tank (for Emission Point AA-004): 1,700-gallon fixed roof tank 	
AD-143	T-143	Recycled Polymer Tank: 5,500-gallon fixed roof tank	
AD-200	T-200	Diesel Tank: 550-gallon fixed roof tank	
AD-401	T-7	Miscellaneous Monomer/Polymer Tanks: 28 Fixed roof tanks ranging from 12,000 gallons to 20,000 gallons	
	T-9 through T-10		
	T-401 through      T-404		
	T-801 through     T-829		
	T-901 through       T-909		
AD-601	CS1-AMA	Maleic Anhydride Tank: 7,925-gallon fixed roof tank venting to either Scrubber (AC-511) or atmosphere	
AD-602	CS1-SAS	SAS Monomer/MAS Polymer Tank: 13,267-gallon fixed roof tank venting to Scrubber (AC-510)	
AD-603	CS1-MAS	SAS Monomer/MAS Polymer Tank: 13,267-gallon fixed roof tank	
AD-604	CP1-APS	Ammonium Persulfate Solution/Sodium Persulfate Solution Tank: 528-gallon fixed roof tank	
AD-605	CP1-EDTA	EDTA Tetrasodium Solution Tank: 528-gallon fixed roof tank	
AD-606	CS1-EL	SAS Monomer/SAS Shutdown/Wash Water Tank: 10,281-gallon fixed roof tank venting to either Scrubber (AC-510) or atmosphere	
AD-607	CS2-EL	MAS Polymer/MAS Shutdown/Wash Water Tank: 10,281-gallon fixed roof tank	
AD-830	--	Hazardous Waste Tank: 2,100-gallon fixed roof tank with emissions routed to Thermal Oxidizer (AB-100)
Tank contains unreacted allyl chloride, salt, and reaction byproducts	
AD-831	--	Hazardous Waste Tank: 6,000-gallon fixed roof tank with emissions routed to Thermal Oxidizer (AB-100)
Tank contains unreacted allyl chloride, salt, and reaction byproducts	
FUG	--	Fugitives from Equipment Leaks	
MISC	--	Fugitive emissions from equipment upkeep, general maintenance, and low emitting activities including empty container washing, tank cleanout, relief valve maintenance, laboratory hoods, and portable fixed roof frac tanks for storage of monomer and polymer products.	

PROJECT/PERMIT ACTION DESCRIPTION

Polychemie has applied for a modification of their Synthetic Minor Operating Permit (SMOP) that was issued on May 20, 2024. The facility has requested the following modifications to the SMOP:

•	Allow flexibility to also store material from the SAS and MAS processes in AD-606 and AD-607, respectively. 

•	Increase design capacity for AD-602 and AD-603 from 12,500 gallons to 13,267 gallons. 

•	Remove AD-603 and add AD-606 to the description of Emission Point AC-510 to read “Controls emissions from SAS Monomer Production (AA-530), SAS/MAS Storage Tank (AD-602), and SAS Monomer/SAS Shutdown/Wash Water Tank (AD-606), which may also vent to atmosphere.”

•	Correct the storage tank number referenced for AC-511 to AD-601 instead of AD-610 and change the description to read “Controls emissions from MAS Polymer Production/Neutralization (AA-530) and maleic anhydride storage tank (AD-601), which may also vent to atmosphere.”

•	Change the description of AD-602 to read “SAS Monomer/MAS Polymer Tank: 13,627-gallon fixed roof tank venting to Scrubber (AC-510).”

•	Change the description of AC-511 to read “Controls emissions from MAS Polymer Production/Neutralization (AA-530) and maleic anhydride storage tank (AD-601), which may also vent to the atmosphere.”

•	Change the description of AD-603 to read “SAS Monomer/MAS Polymer Tank: 13,267-gallon fixed roof tank.”

•	Change the description of AD-606 to read “SAS Monomer/SAS Shutdown/Wash Water Tank: 10,281-gallon fixed roof tank venting to either Scrubber (AC-510) or atmosphere.”

EMISSION SUMMARY

Comparison of Facility-Wide Uncontrolled and Proposed Allowable Emissions in tons per year (tpy)	
Pollutant	Uncontrolled Emissions
(tpy)	Proposed Allowable Emissions
(tpy)	Proposed Allowable Exceed Title V Major Source Threshold (Yes/No)?	
PM	2.58	2.58	No	
PM10	2.58	2.58	No	
PM2.5	2.58	2.58	No	
SO2	53.27	1.33	No	
NOx	36.76	36.76	No	
CO	28.11	28.11	No	
VOC	77.42	16.84	No	
Individual HAP
Allyl Chloride	30.26	6.20	No	
Total HAP	40.63	10.39	No	

Polychemie has the potential to exceed the Title V thresholds of 25.0 and 10.0 tpy for Total HAPs and Individual HAPs, respectively. Allyl Chloride is the largest Individual HAP; however, the proposed modifications to the facility have no effect on the Individual and Total HAP emissions. All other HAPs have uncontrolled emissions less than 10.0 tpy. In order to maintain synthetic minor source status, the facility has production rate limits, scrubber/TOX control requirements, and venting requirements. With this permitting action, no new limitations are being added.  

APPLICABLE/PROPOSED PERMIT LIMITATIONS

Emission Point(s)	Pollutant/ Parameter	Limit/Standard	Monitoring	
Facility-Wide	Production Rate	Production is limited to the following: 
DADMAC Monomer - 447 MMlb/yr
Polyamine - 300 MMlb/yr
EDC-Ammonia Polyamine - 8.0 MMlb/yr
SAS – 34.8 MMlb/yr
MAS – 34.8 MMlb/yr	Maintain records of monthly production rates (12 consecutive months)                                 	
AA-004	NMHC               NOx                           CO                      PM	NMHC + NOx – 6.4g/kg-hr
CO – 3.5g/kw-hr
PM – 0.20g/kw-hr	Purchase certified engine	
	Hours of Operation	Limit non-emergency operation hours to less than 50 hours per year	Install non-resettable hour meter	
AA-050             	HAP	Vent all emissions to thermal oxidizers while processes are operating	Continuously monitor combustion chambers (Maintain logs of temperature and maintenance performed)                                             	
AB-100              AB-200		Maintain combustion chamber temperature of 1, 1,500 ºF		
		Vent all emissions from thermal oxidizers to scrubbers		
AA-100 AA-401 AA-530	HAP	Vent all emissions to scrubbers only	Maintain inspection logs and maintain flow meters	
AC-100            AC-101             AC-200                AC-511		Operational requirement for scrubbers		

Note: The Venturi, Packed Tower Scrubber (Emission Point AC-400) is not required to be operated as part of Polychemie’s plan to maintain their status as a Synthetic Minor source. The facility had previously requested that the emission point have its requirements removed to allow for operational flexibility with that specific unit. As such, all emission calculations do not include the control efficiency of Emission Point AC-400. In addition to the removal mentioned above, the requirement to vent emissions from the Hydrochloric Acid Tank (Emission Point AD-006) to Emission Point AC-400 has also been removed.

NSPS APPLICABILITY

40 CFR 60, Subpart Kb (Standards of Performance for Volatile Organic Liquid Storage Vessels (Including Petroleum Liquid Storage Vessels) for Which Construction, Reconstruction, or Modification Commenced After July 23, 1984): 
Subpart Kb applies to Volatile Organic Liquid (VOL) storage vessels with a storage capacity greater than 75 cubic meters (m3) (19,810 gallons). Emission Point AD-001 through AD-004, AD-011, AD-018, and AD-032 meet the storage size criteria to be subject to Subpart Kb. However, these emission points store VOLs with a true vapor pressure less than 3.5 kPa. Therefore, the facility is not subject to Subpart Kb under 40 CFR 60.110b(b).

40 CFR 60, Subpart IIII (Standards of Performance for Stationary Compression Ignition Internal Combustion Engines): 
Subpart IIII applies to compression ignition (CI) internal combustion engines (ICE). Emission Point AA-004 is a 4-stroke CI emergency engine. Therefore, the facility is subject to Subpart IIII.

40 CFR 60, Subpart Dc (Standards of Performance for Small Industrial-Commercial-Institutional Steam Generating Units):
Subpart Dc applies to steam generating units with a design capacity less than 100 MMBtu/hr but greater than 10 MMBtu/hr. Therefore, Emission Points AA-001, AA-002, and AA-005 are subject to Subpart Dc.

MACT APPLICABILITY

40 CFR 63, Subpart ZZZZ (National Emissions Standards for Hazardous Air Pollutants for Stationary Reciprocating Internal Combustion Engines): 
Subpart ZZZZ applies to stationary reciprocating internal combustion engines (RICE) located at area and major sources of HAP emissions. Emission Point AA-004 is subject to Subpart ZZZZ. However, under 40 CFR 63.6590(c)(1), Emission Point AA-004 shall meet all requirements under Subpart ZZZZ by complying with all applicable requirements under 40 CFR 60, Subpart IIII. Therefore, the facility is subject to Subpart ZZZZ, and no further requirements under Subpart ZZZZ will apply to the facility.

PUBLIC PARTICIPATION

The 30-day public notice period began on August 12, 2026, when the notice was posted on MDEQ’s website and ends September 11, 2026.