Date: July 22, 2011

(Finalized September 30, 2011)

Subject: Trip Report for Site Visit – Domtar Paper Company, LLC

Risk and technology review for pulp and paper production and combustion 

sources NESHAP 

I. Purpose

The purpose of the site visit to Domtar Paper Company in Bennettsville, South Carolina,

was to obtain information about pulp and paper operations, equipment, and air pollution 

control devices. This information-gathering effort was part of regulatory development 

work for the Risk and Technology Review (RTR) for the National Emission Standards 

for Hazardous Air Pollutants (NESHAP) for the pulp and paper industry.

II. Place and Date

Domtar Paper Company, LLC (Marlboro Mill)

585 Willamette Road, Bennettsville, SC 29512

(843) 454-8955

July 20, 2011

Mailing address:

PO Box 678, Bennettsville, SC 29512

III. Attendees

Domtar Paper Company, LLC

• Bill Edwards, VP/Mill Manager

• Athena Strickland, Technical Services Manager

• Guy Martin, Senior Director - Environment

• Chuck Thames, Final Products Manager

• Monte Batchelor, Health and Safety Manager

• Chris Gore, Pulp and Utilities Manager

• Bill Seamans, Fiberline Manager

• Ray Crouse, Utilities Manager

• Amber Bowen, Process Engineer

• John Pinkerton, NCASI

U.S. Environmental Protection Agency (EPA)

• Bill Schrock, Environmental Engineer, Office of Air Quality Planning and Standards 

 (OAQPS)/Sector Polices and Programs Division (SPPD)/Natural Resources Group 

 (NRG)

• John Bradfield, Environmental Engineer, OAQPS/SPPD/NRG

• Kelley Spence, Environmental Engineer, OAQPS/SPPD/NRG

• Katie Hanks, EPA contractor, Research Triangle Institute (RTI)
IV. Visit Summary

The site visit began with a meeting to discuss mill background, safety, and the agenda of 

the visit. A flow chart of the process, provided by Domtar, is attached (Attachment 1). 

Following the meeting, a tour of the facility was provided and the following areas were 

observed: wood yard, pulp mill, bleach plant, recovery area, caustic area, power house, 

wastewater treatment, and paper making area. The information obtained during the site 

visit and from the Information Collection Request (ICR) response is discussed below. 

The topics discussed are (A) General Information, (B) Pulp Mill, (C) Bleach Plant, (D) 

Paper Mill, (E) Chemical Recovery and Energy Generation, and (F) Wastewater 

Treatment. 

A. General Information

Marlboro Paper Mill (NEI47074, RTI107), the most recently opened pulp and paper mill 

in the United States, was opened by Willamette in 1990, acquired by Weyerhaeuser in 

2002, and became part of Domtar in 2007. The facility was the last Greenfield project 

installed in the US. Domtar has 10 paper mills. The Marlboro Paper mill produces

approximately 380,000 tons of uncoated freesheet per year and 65,000 air-dried metric 

tons of market pulp per year. Domtar also uses best practices and benchmarking across 

the company, and with other companies, to improve efficiency and decrease 

environmental impacts. 

The Marlboro mill owns 2,300 acres of land near the Pee Dee River and employs 

approximately 325 people; the facility is ISO 14001 certification ready. The main 

products from the facility are bleached softwood and bleached hardwood kraft market 

pulp and uncoated freesheet. The Marlboro mill is FSC (Forest Stewardship Council) 

third party certified and 100% of their wood meets the FSC controlled wood standard. 

Up to 2.2 million tons of wood per year are used to produce a maximum of 1410 

bleached air dried tons of pulp per day, which can be used to produce up to 1140 off 

machine tons of paper per day and 518 air dry tons of market pulp per day. The mill also 

utilizes baled recycled paper for some grades. The mill has an annual paper production 

capacity of 416,100 tons and an annual pulp production capacity of 189,070 tons, with 1 

pulp line and 1 paper machine. The facility is a fully integrated facility with a wood yard, 

pulp mill, bleach plant, recovery and causticizing area, utilities, paper mill, and 

wastewater treatment. A flow diagram of the processes at the mill can be found in 

Attachment 1. 

B. Pulp Mill

Wood arrives at the mill in the form of logs, which are debarked and chipped, and chips. 

Chips are screened prior to pulping, Figure 1. Up to 2.2 million green tons of wood per 

year is consumed for pulping. The Marlboro mill utilizes the kraft process with 8 RDH 

batch digesters for pulping hardwood and softwood. The RDH process (Rapid 

Displacement Heating) is a more efficient process for delignification than conventional 
batch digesters. The digester is charged with chips similar to a regular digester and is 

packed with steam allowing for increased chip capacity in the digester. Steam and air are

then displaced with cool black, hot black and hot white liquors. This process provides for 

a more uniform and stronger pulp and lower steam consumption. The mill chose to use 

RDH batch digesters instead of a continuous digester because of the need to switch 

between the pulping of hardwood and softwood. Up to 1450 air-dried tons of unbleached 

pulp is produced per day. By-products of the process are resin soaps (10,000 tons 

annually) and turpentine (100,000 gals annually). The mill also purchases secondary 

pulp. 

Chipping 

and 

Debarking

Digesters Chip 

Screens

Blow Tank

Brown 

Stock 

Washing

Screening

To Oxygen 

Delignification

Chips

Logs

Figure 1: Wood yard and pulp mill process flow diagram

C. Bleach Plant

The bleach plant utilizes an elemental chlorine free (ECF) bleaching sequence, D (Eop) D 

with oxygen delignification as a pretreatment, Figure 2. The R10 process is used to 

generate the chlorine dioxide used in the process. A Lurgi-process was previously used at 

the mill to generate chlorine dioxide, but it was shutdown due to environmental concerns,

large energy consumption, and high maintenance costs. The mill produces up to 1410 airdried tons of bleached pulp per day. Currently 20% is sold as market pulp and 80% is 

used at the facility to produce paper. 
Oxygen 

Delignification

Unbleached 

Pulp Washers D1 Bleach 

Stage

D1 Washer EO Bleach 

Stage EO Washer

D2 Bleach 

Stage D2 Washer

Bleach Pulp 

Storage

Figure 2: Bleach plant process flow diagram

D. Paper Mill

There is one twin-wire paper machine with a capacity of 416,100 tons per year, and one 

pulp dryer with a capacity of 189,070 tons per year at the Marlboro facility, Figures 3 and 

4. The machine utilizes a sym-former and has a machine width of 354 inches and a 

maximum speed of 4,500 feet per minute. A sym-sizer is used to surface size (or surface 

coat) the sheet using a cooked starch-based coating. The main grades produced are 

market pulp (bleached softwood and bleached hardwood) and uncoated freesheet. 
Refiners Screen Blend 

Chest

Machine 

Chest Cleaners Screen

Whitewater

HW pulp (from refiners)

SW pulp 

Headbox& 

Former Wet Press Dryers

Size Press Dryers Reel

Figure 3: Paper mill process flow diagram
Pressure 

screens

Headbox Machine 

Chest

Double 

wire 

Former & 

Press

Heavy 

Duty Press Pulp Dryer

To Bale Line 

and Warehouse

Whitewater

Pulp

Whitewater

Figure 4: Pulp dryer process flow diagram

E. Chemical Recovery and Energy Generation

The mill utilizes one recovery boiler with a solids capacity of 4.4 million pounds per day 

and a steam generation capacity of 628,400 pounds per hour. The recovery boiler 

produces approximately 75% of the steam required for mill processes by burning black 

liquor and utilizes 5 air zones to reduce NOx emissions, control CO emissions and reduce 

carryover. The chemical recovery process and causticizing are shown in Figure 5 and 6, 

respectively. The facility boasts the best SO2 emission rate (0.07 kg/tonne) of pulp and 

paper facilities in North America, even though it burns petroleum coke in the lime kiln. 

One expressed concern for the facility is separate standards for individual HAPs in the 

boiler MACT; the boilers may meet one criterion (i.e. NOx) by a significant margin, but 

it may barely meet other criteria (i.e. CO) because the control of some pollutants cases

increases in other pollutants. The mill also uses a 280,000 pound per hour biomass fueled 

power boiler and a 51.4 MW turbine generator, to generate power. There is also a small 

medium pressure gas fire package boiler on site that is used to supplement the steam 

system as needed. This boiler is rated up to 225,000 pounds per hour. The mill focuses 

on energy benchmarking; by reducing energy requirements, the facility will reduce its 

greenhouse gas emissions. Only about 5% of the mills steam needs are supplied with 

natural gas. River water must be treated and de-mineralized before utilization as boiler 

feedwater. 
Evaps(6 

and a soap 

skimmer)

Recovery 

Boiler Concentrators

Smelt 

Dissolving 

Tank

Green 

Liquor 

Clarifier

To Causticizers

Liquor 

From 

Digesters

Evaps(4 

and a soap 

skimmer)

Smelt

Figure 5: Recovery process flow diagram

Lime Mud 

Washer

White liquor 

Clarifier

Pre-Coat 

Filter Lime Kiln

Green 

Liquor

Causticizers

To Digesters

White Liquor 

Slaker

Lime

Figure 6: Causticizing process flow diagram
F. Wastewater Treatment

The mill is a low-odor facility, as it is a totally collected kraft process, and approximately 

50.6 m3 of water is used per tonne of paper. The waste sent to the landfill is 

approximately 5 kg per tonne of paper. Approximately 16 million gallons of effluent per 

day are sent to wastewater treatment and the Marlboro mill utilizes an aeration 

stabilization basin (ASB). Note that methanol is removed via a steam stripper integrated 

with the black liquor evaporators and NCG incinerator. Effluent is processed using a 

primary clarifier, 2 ASBs, and 3 polishing ponds, Figure 7. Water can be retained for up 

to 65 days in wastewater treatment, before returning to the river. Sludge from the primary 

clarifier is pressed and burned for energy in the biomass boiler. 

Primary 

Clarifier

No. 1 

ASB

No. 2 

ASB

No. 3 

Polishing 

Pond

No. 2 

Polishing 

Pond

No. 1 

Polishing 

Pond

Pee Dee 

River

Effluent

Figure 7: Wastewater treatment process flow diagram

1 Attachment