AkzoNobel Tb Aquatreat Biocides-1

Aquatreat® BiocidesCost-effective, broad-spectrum biocides

2

IntroductionAquatreat Biocides are EPA-registered, non-oxidizing dithiocarbamates that have a long history of proven performance. In cooling towers and airwashers, experience has shown that Aquatreat Biocides are effective in controlling both planktonic and sessile microorganisms. In paper mills, Aquatreat Biocides are known to be the most cost-effective materials available for the control of slime-forming bacteria and fungi in both virgin and recycle mills. For both beet and cane sugar mills, Aquatreat Biocides can be used to effectively control mesophilic and thermophilic bacteria that commonly foul the sugar production process. Aquatreat Biocides are especially effective in controlling sulfate-reducing bacteria in many applications, including drilling fluids and petroleum recovery waters. Additional uses for Aquatreat Biocides include sapstain control, fuel storage and in-flue gas desulfurization thickeners.

Performance Features• EPA registered for a wide range of applications• Meet FDA requirements for use in paper and sugar applications• Cost effective• Effective against a broad spectrum of microorganisms, including

bacteria, fungi and algae: - Aerobic and anaerobic bacteria - Sulfate-reducing bacteria (SRB) - Yeasts and molds - Legionella• Compatibility and strong performance in a wide range of environments/

conditions - Broad pH and temperature stability - Organic loading - Dissolved and suspended solids• Not persistent in discharge waters• Favorable handling and toxicity compared with competitive materials

Aquatreat®

BiocidesEffective against a broad spectrum of microorganisms

Product ChemistryAquatreat Biocides are based on dithiocarbamate chemistry. Aquatreat SDM (Figure 1) and Aquatreat KM (Figure 2) are single-component biocides based on the sodium and potassium salts of dimethyldithiocarbamate. Aquatreat DNM-9, Aquatreat DNM-30 and Aquatreat DNM-360 are dual-component biocides based on a blend of sodium dimethyldithiocarbamate and disodium ethylene-bis-dithiocarbamate (Figure 3). Aquatreat Biocides are applicable for a wide range of industrial uses. Table 1 summarizes acceptable use patterns for these products.

ToxicologyAquatreat Biocides have a low order of toxicity to humans. Tables 2 and 3 show comparative data for Aquatreat DNM-30 in eye and skin irritation studies. Figures 4 and 5 show comparative oral and dermal toxicity with Aquatreat DNM-30 and other commonly used biocides. Aquatreat Biocides are known to be toxic to fish and aquatic organisms. As with any biocide, care must be taken to eliminate the possibility of release of Aquatreat Biocides into natural waterways such as lakes, streams, rivers and oceans. Aquatreat products are not persistent biocides. Degradation of the products occurs as a result of oxidation, sunlight, lower pH and microbial action.

3

BiocideClassification under

21 CFR 191.12

Aquatreat DNM-30 Non-irritant

Isothiazolin Corrosive

Gluteraldehyde Severe Irritant

DBNPA Severe Irritant

BiocideClassification under

21 CFR 191.11

Aquatreat DNM-30 Non-irritant

Isothiazolin Severe Irritant

Gluteraldehyde Severe Irritant

DBNPA Severe Irritant

ProductCooling Towers

Air Washers

Pulp & Paper Mills

Cane Sugar Mills

Beet Sugar Mills

Drilling Fluids

Hydro-Carbon Fluids

Petroleum Recovery

Sapstain Control

Aquatreat SDM • • • • • • •

Aquatreat KM • • • •

Aquatreat DNM-9 • • • • • • •

Aquatreat DNM-30 • • • • • • • •

Aquatreat DNM-360 • • • • • • •

Table 1: Application use patterns

Aquatreat® SDM Aquatreat KM Aquatreat DNM-9, DNM-30, DNM-360

Figure 1: Sodium Dimethyldithiocarbamate

Figure 2: Potassium Dimethyldithiocarbamate

Figure 3: Dual-Component Biocides

Figure 4: Oral Toxicity - LD50

Table 2: Eye Irritation in Rabbits

Figure 5: Dermal Toxicity - LD50

Table 3: Skin Irritation in Rabbits

H3C

CH3

S-+NaN

S

C

H3C

CH3

S-+KN

S

C

H3C

CH3

S-+Na S-+Na

S-+Na

N NH

HN

S S

S

C

1600

1400

1200

1000

800

600

400

200

0AQUATREAT

DNM-30ISOTHIAZOLIN GLUTERALDEHYDE

mg

/kg

3000

2500

2000

1500

1000

500

0

mg

/kg

AQUATREAT DNM-30

ISOTHIAZOLIN GLUTERALDEHYDE

0

50

100

150

200

250

0 1 2 3 4 5 6 7

Maintenance Dose

SlugDosagem

g C

hlo

rop

hyll/

cm2

mg

Chl

oro

phy

ll/cm

2

WEEK

DAYS

0

20

40

60

80

100

0 20 40 60 80

Dit

hio

carb

amat

e

NaO

Cl

Dit

hio

carb

amat

e

NaO

Cl

H3C

CH3

S-+NaN

S

C

H3C

CH3

S-+KN

S

C

H3C

CH3

S-+Na S-+Na

S-+Na

N NH

HN

S S

S

C

1600

1400

1200

1000

800

600

400

200

0AQUATREAT


mg

/kg

3000

2500

2000

1500

1000

500

0

mg

/kg

AQUATREAT DNM-30


0

50

100

150

200

250

0 1 2 3 4 5 6 7

Maintenance Dose

SlugDosagem

g C

hlo

rop

hyll/

cm2

mg

Chl

oro

phy

ll/cm

2

WEEK

DAYS

0

20

40

60

80

100

0 20 40 60 80

Dit

hio

carb

amat

e

NaO

Cl

Dit

hio

carb

amat

e

NaO

Cl

H3C

CH3

S-+NaN

S

C

H3C

CH3

S-+KN

S

C

H3C

CH3

S-+Na S-+Na

S-+Na

N NH

HN

S S

S

C

1600

1400

1200

1000

800

600

400

200

0AQUATREAT


mg

/kg

3000

2500

2000

1500

1000

500

0

mg

/kg

AQUATREAT DNM-30


0

50

100

150

200

250

0 1 2 3 4 5 6 7

Maintenance Dose

SlugDosagem

g C

hlo

rop

hyll/

cm2

mg

Chl

oro

phy

ll/cm

2

WEEK

DAYS

0

20

40

60

80

100

0 20 40 60 80

Dit

hio

carb

amat

e

NaO

Cl

Dit

hio

carb

amat

e

NaO

Cl

H3C

CH3

S-+NaN

S

C

H3C

CH3

S-+KN

S

C

H3C

CH3

S-+Na S-+Na

S-+Na

N NH

HN

S S

S

C

1600

1400

1200

1000

800

600

400

200

0AQUATREAT


mg

/kg

3000

2500

2000

1500

1000

500

0

mg

/kg

AQUATREAT DNM-30


0

50

100

150

200

250

0 1 2 3 4 5 6 7

Maintenance Dose

SlugDosagem

g C

hlo

rop

hyll/

cm2

mg

Chl

oro

phy

ll/cm

2

WEEK

DAYS

0

20

40

60

80

100

0 20 40 60 80

Dit

hio

carb

amat

e

NaO

Cl

Dit

hio

carb

amat

e

NaO

Cl

H3C

CH3

S-+NaN

S

C

H3C

CH3

S-+KN

S

C

H3C

CH3

S-+Na S-+Na

S-+Na

N NH

HN

S S

S

C

1600

1400

1200

1000

800

600

400

200

0AQUATREAT


mg

/kg

3000

2500

2000

1500

1000

500

0

mg

/kg

AQUATREAT DNM-30


0

50

100

150

200

250

0 1 2 3 4 5 6 7

Maintenance Dose

SlugDosagem

g C

hlo

rop

hyll/

cm2

mg

Chl

oro

phy

ll/cm

2

WEEK

DAYS

0

20

40

60

80

100

0 20 40 60 80

Dit

hio

carb

amat

e

NaO

Cl

Dit

hio

carb

amat

e

NaO

Cl

4

Cooling Towers and Air WashersAquatreat® Biocides are particularly effective in controlling problematic organisms in both open recirculating and closed cooling water systems. In open recirculating systems, Aquatreat Biocides are effective against algae and bacteria commonly found in bulk water and in biofilms. In closed-loop systems, it is particularly important to control sulfate-reducing bacteria (SRB), denitrifying bacteria and other anaerobic bacteria. Due to their functionality and compatibility in reducing environments, Aquatreat Biocides are often the biocides of choice in closed-loop cooling systems. In air washers, Aquatreat Biocides offer the user broad functionality and a low order of toxicity relative to other commonly used materials.

Algae Control Using Aquatreat DNM-30Algae are organisms that use light energy and carbon dioxide from the air to produce organic biomass. They represent a broad range of unicellular and filamentous organisms. Most system operators also refer to the cyanobacteria (blue-green algae) as members of the algal group, although they are most closely related to bacteria.

Algae cause a number of direct and indirect problems in water treatment

Algae Type Source MIC*

Ulothrix spp. Filamentous green algae Cooling tower effluent 5-10

Heterocapsa pygmaea Slime-forming algae Estuary in-take water 2.5-5

Euglena gracilis Unicellular flagellate ATCC* 12894 5-10

Chlorella pyrenoidosa Unicellular green algae ATCC 7516 15-20

Scenedesmus obliquus Unicellular green algae ATCC 11457 20-25

Phormidium spp. (mat) Filamentous blue green Cooling tower isolate (Gulf coast) 20-25

Oscillatoria prolifera Filamentous blue green Unknown 2.5-5

Oscillatoria spp. Filamentous blue green Carolina Biological 1-5

Cooling tower enrichment Mixed culture of green and blue-green algae Cooling tower (South Dakota) 15-20

Cooling tower enrichment Mixed culture of green and blue-green algae Cooling tower (southern Minnesota) 20-25

Cooling tower enrichment Mixed culture of green and blue-green algae Cooling tower (Montana) 35-40

* The Minimum Inhibitory Concentration (MIC) tests were conducted in the medium specified by the source supplier (American Type Culture Collection, Rockville, MD; Carolina Biological Co., [CBC]) or in Alga Gro Medium (CBC) for pure cultures or in Alga Gro Medium reconstituted in filter-sterilized cooling tower basin water for cooling tower enrichments.

Table 4: Aquatreat DNM-30 Efficacy Data

Cooling Water Applications

systems. Directly, many algae grow in dense fibrous mats that plug distribution piping, accelerate corrosion and overall reduce system performance. These mats also provide areas for the growth of corrosion-causing anaerobic bacteria. Another important effect of algal growth is the continuous removal of carbon dioxide during the daylight hours. This can alter water chemistry and complicate normal scale control treatment programs.

Indirectly, the consequence of algal growth can be even more severe and detrimental. Algae convert inorganic carbon (CO2) into organic biomass. As this biomass dies, it contributes nutrients that fuel the growth of other bacteria. These bacteria can foul heat exchanger surfaces and contributeto corrosion, e.g., sulfate-reducing bacteria.

Laboratory StudiesLaboratory studies are often used to obtain preliminary efficacy data and establish baseline dose response information. It is important that a biocide demonstrates a broad range of activity. Aquatreat DNM-30 has been tested against a number of pure and field-obtained enrichment cultures from a variety of sources as shown in Table 4. These data show that Aquatreat DNM-30 is effective at low-use concentrations against a wide variety of filamentous and unicellular algae.

5

Field StudiesAquatreat® dithiocarbamates have been used and evaluated in a number of cooling water systems for their efficacy against planktonic and mat-forming algae. Figures 6 and 7 (following page) document their ability to control algal mat formation using alternating slug and maintenance dosages.

System Conditions• Bulk water capacity—35,000 gallons• Bulk water temperature—80–100° F• Bulk water pH—8.0–8.6• Total dissolved solids—1,000–2,000 ppm

Figure 6 depicts data from a cooling tower deck in southern Minnesota. The tower deck had severe algal and cyanobacterial fouling problems, especially in the mid-summer cooling season. Replicate 5 cm2 coupons were installed on the deck early in the season, and algal growth was monitored by removing coupons and measuring algal biomass by chlorophyll determination. Without biocide treatment (Figure 6) greater than 200 mg/cm2, algal biomass accumulated on the coupons. Following an initial slug dosage (400 ppm) of Aquatreat DNM-30, the algal biomass was reduced to about 50 mg/cm2 and was readily maintained at less than 100 mg/cm2 with a routine maintenance dosage of 20-40 ppm. Figure 7 shows the alternating treatment of Aquatreat DNM-30 (20-40 ppm) and sodium hypochlorite in the same system. In this study, algal growth on the tower deck was more effectively controlled during Aquatreat DNM-30 treatment than with sodium hypochlorite.

H3C

CH3

S-+NaN

S

C

H3C

CH3

S-+KN

S

C

H3C

CH3

S-+Na S-+Na

S-+Na

N NH

HN

S S

S

C

1600

1400

1200

1000

800

600

400

200

0AQUATREAT


mg

/kg

3000

2500

2000

1500

1000

500

0

mg

/kg

AQUATREAT DNM-30


0

50

100

150

200

250

0 1 2 3 4 5 6 7

Maintenance Dose

SlugDosagem

g C

hlo

rop

hyll/

cm2

mg

Chl

oro

phy

ll/cm

2

WEEK

DAYS

0

20

40

60

80

100

0 20 40 60 80

Dit

hio

carb

amat

e

NaO

Cl

Dit

hio

carb

amat

e

NaO

Cl

H3C

CH3

S-+NaN

S

C

H3C

CH3

S-+KN

S

C

H3C

CH3

S-+Na S-+Na

S-+Na

N NH

HN

S S

S

C

1600

1400

1200

1000

800

600

400

200

0AQUATREAT


mg

/kg

3000

2500

2000

1500

1000

500

0

mg

/kg

AQUATREAT DNM-30


0

50

100

150

200

250

0 1 2 3 4 5 6 7

Maintenance Dose

SlugDosagem

g C

hlo

rop

hyll/

cm2

mg

Chl

oro

phy

ll/cm

2

WEEK

DAYS

0

20

40

60

80

100

0 20 40 60 80

Dit

hio

carb

amat

e

NaO

Cl

Dit

hio

carb

amat

e

NaO

Cl

Figure 6: Algal Biomass Reduction Using DNM-30

Figure 7: Algal Control: Aquatreat DNM-30 vs. Hypochlorite

6

Problematic Bacterial Control Using Aquatreat® DNM-30Bacteria pose various mechanical, economic and public health issues in cooling water systems. As a result, microbiologically influenced corrosion (MIC) is recognized as one of the most significant issues in industrial water treatment, resulting in equipment failure and economic loss. Bacterial accumulation in the form of biofilms contributes to significant mechanical problems, such as fouling of heat exchangers, restriction of flow and fouling of cooling tower fill. The formation of biofilm in heat exchangers or on cooling tower fill can have a significant impact on the costs associated with achieving desired cooling. The presence of bacteria such as Legionella spp. in cooling water systems has been recognized as a major public health issue.

There is a large variety of aerobic and anaerobic bacteria that are found in industrial cooling water systems. Aquatreat DNM-30 has been demonstrated to be effective against a wide variety of bacteria. Table 5 shows the MIC, in parts per million, of Aquatreat DNM-30 necessary to control a number of different gram negative and gram positive bacteria. Figure 8 shows effectiveness of Aquatreat DNM-30 against aerobic heterotrophic bacteria in an industrial air washer.

Gram negative bacteria such as the Pseudomonas species listed above are likely to be found in most cooling water systems and are among the most difficult to control with commercially available biocides. Pseudomonads are recognized as prolific biofilm-producing bacteria. Gram positive bacteria such as the spore-forming bacilli are also found in industrial water systems. These bacteria contribute to biofouling and other microbiological-related problems. Iron-oxidizing bacteria, including Sphaerotilus, form surface deposits and accelerate localized corrosion.

Other bacteria, such as Escherichia and Salmonella, are among the common waterborne pathogens.

Table 5: Minimum Inhibitory Concentrations for Problematic Bacteria

Organism SourceEnrichment Medium

MIC* (ppm)

Gram Negative Bacteria

Escherichia coli ATCC 29990 API-H (mod) 55-60

Escherichia coli UM 0315 API-H (mod) 60-65

Pseudomonas fluorescens ATCC 13525 API-H (mod) 85-90

Pseudomonas putida ATCC 12633 API-H (mod) 60-65

Enterobacter aerogenes UM 0298 API-H (mod) 35-40

Salmonella typhirmurium ATCC 14028 API-H (mod) 55-60

Gram Positive Bacteria

Bacillus cereus NRRL B4278 API-H (mod) 15-20

Staphylococcus aureus UM 0115 API-H (mod) 5-10

Iron Oxidizing Bacteria

Sphaerotilus natans ATCC 15291 Iron isolation medium std.

1-5

CFU

/mL

1.00E+07

1.00E+03

1.00E+04

1.00E+05

1.00E+06

0 ppm

91.8%

25 ppm

97.3%50 ppm

Time (H)

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

0 5 10 15 20 25 30

CFU

/mL

1.00E+08

Control (pH 5)

DNM-30 (pH 5)

Control (pH 7)

DNM-30 (pH 7)

Control (pH 9)

DNM-30 (pH 9)

0

50

100

150

200

250

300

350

400

SMB DBNPA DN-30 DNM-30 Isothiazolin Quat

MIC

(pp

m A

ctiv

e)

0

10

100

1,000

10,000

ppm DNM-30 (active)

Leg

ione

lla C

FU/m

L

0 20 60 100

CFU/mL

Hours

1.00E+07

0 20 40 60 80 100 120 140 160

MP

N S

RB

/g S

lud

ge

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06Control

Dithiocarbamateat 120 ppm(as product)

TOTAL ANAEROBES

1.00E+07

1.00E+03

1.00E+04

1.00E+05

1.00E+06

TOTAL SRB

Control

Control

100 ppmDNM-30

100 ppmDNM-30

Time (Weeks)

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

120 ppm DNM-30

0 2 4 6 8 10 12

MP

N S

RB

/mL

Time (H)

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

0 5 10 15 20 25 30

CFU

/mL

or

MP

N/m

L

Heterotrophs (0 ppm)

Denitrifiers (0 ppm)



CFU

/cm

2

Figure 8: Effectiveness of Aquatreat DNM-30 against Aerobic Heterotrophs in an Industrial Air Washer

7

While most cooling water systems are operated at alkaline pH, it is important for a biocide to exhibit activity over a broad pH range. Figure 9 shows the activity of Aquatreat® DNM-30 at pH 5, 7 and 9. The data demonstrate effectiveness over a broad pH range against aerobic bacteria in a cooling water sample.

A current and especially serious public health problem found in industrial water systems is the occurrence of Legionella pneumophilia. Legionella is a relatively ubiquitous organism found in water and soil. Because of the nature of industrial cooling tower systems, Legionella has the potential to accumulate and be distributed in tower aerosols. The organism is unusual in that it invades and multiplies within an amoeba. When outside of the amoeba, the bacterium is relatively easy to control.

When present inside the amoeba, its control is much more difficult. The conditions presented in Figure 10 show how the functionality of Aquatreat DNM-30 for control of unassociated Legionella compares with that of other available biocides. Figure 11 shows the efficacy of Aquatreat DNM-30 for amoeba-associated bacteria. This study shows that DNM-30 has the capacity to penetrate amoeba and kill intracellular Legionella.

CFU

/mL

1.00E+07

1.00E+03

1.00E+04

1.00E+05

1.00E+06

0 ppm

91.8%

25 ppm

97.3%50 ppm

Time (H)

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

0 5 10 15 20 25 30

CFU

/mL

1.00E+08

Control (pH 5)

DNM-30 (pH 5)

Control (pH 7)

DNM-30 (pH 7)

Control (pH 9)

DNM-30 (pH 9)

0

50

100

150

200

250

300

350

400


MIC

(pp

m A

ctiv

e)

0

10

100

1,000

10,000

ppm DNM-30 (active)

Leg

ione

lla C

FU/m

L

0 20 60 100

CFU/mL

Hours

1.00E+07

0 20 40 60 80 100 120 140 160

MP

N S

RB

/g S

lud

ge

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06Control


TOTAL ANAEROBES

1.00E+07

1.00E+03

1.00E+04

1.00E+05

1.00E+06

TOTAL SRB

Control

Control

100 ppmDNM-30

100 ppmDNM-30

Time (Weeks)

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

120 ppm DNM-30

0 2 4 6 8 10 12

MP

N S

RB

/mL

Time (H)

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

0 5 10 15 20 25 30

CFU

/mL

or

MP

N/m

L





CFU

/cm

2

Figure 9: Broad pH Performance of Aquatreat DNM-30

CFU

/mL

1.00E+07

1.00E+03

1.00E+04

1.00E+05

1.00E+06

0 ppm

91.8%

25 ppm

97.3%50 ppm

Time (H)

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

0 5 10 15 20 25 30

CFU

/mL

1.00E+08

Control (pH 5)

DNM-30 (pH 5)

Control (pH 7)

DNM-30 (pH 7)

Control (pH 9)

DNM-30 (pH 9)

0

50

100

150

200

250

300

350

400


MIC

(pp

m A

ctiv

e)

0

10

100

1,000

10,000

ppm DNM-30 (active)

Leg

ione

lla C

FU/m

L

0 20 60 100

CFU/mL

Hours

1.00E+07

0 20 40 60 80 100 120 140 160

MP

N S

RB

/g S

lud

ge

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06Control


TOTAL ANAEROBES

1.00E+07

1.00E+03

1.00E+04

1.00E+05

1.00E+06

TOTAL SRB

Control

Control

100 ppmDNM-30

100 ppmDNM-30

Time (Weeks)

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

120 ppm DNM-30

0 2 4 6 8 10 12

MP

N S

RB

/mL

Time (H)

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

0 5 10 15 20 25 30

CFU

/mL

or

MP

N/m

L





CFU

/cm

2

CFU

/mL

1.00E+07

1.00E+03

1.00E+04

1.00E+05

1.00E+06

0 ppm

91.8%

25 ppm

97.3%50 ppm

Time (H)

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

0 5 10 15 20 25 30

CFU

/mL

1.00E+08

Control (pH 5)

DNM-30 (pH 5)

Control (pH 7)

DNM-30 (pH 7)

Control (pH 9)

DNM-30 (pH 9)

0

50

100

150

200

250

300

350

400


MIC

(pp

m A

ctiv

e)

0

10

100

1,000

10,000

ppm DNM-30 (active)

Leg

ione

lla C

FU/m

L

0 20 60 100

CFU/mL

Hours

1.00E+07

0 20 40 60 80 100 120 140 160

MP

N S

RB

/g S

lud

ge

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06Control


TOTAL ANAEROBES

1.00E+07

1.00E+03

1.00E+04

1.00E+05

1.00E+06

TOTAL SRB

Control

Control

100 ppmDNM-30

100 ppmDNM-30

Time (Weeks)

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

120 ppm DNM-30

0 2 4 6 8 10 12

MP

N S

RB

/mL

Time (H)

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

0 5 10 15 20 25 30

CFU

/mL

or

MP

N/m

L





CFU

/cm

2

Figure 10: Reduction of unassociated Legionella pneumophila

Figure 11: Reduction of Amoeba-Grown Legionella (6-hr exposure) using Aquatreat DNM-30

8

SRB DataThe sulfate reducers are a group of anaerobic bacteria that produce hydrogen sulfide from the reduction of sulfate and other sulfur species during their growth process. While difficult to detect, SRB are ubiquitous in most industrial water systems where anaerobic conditions exist. SRB cause severe corrosion and odor problems in both open recirculating and closed cooling water systems. The economic implications of SRB in industrial water systems are significant due to the intensity of under-deposit and pitting corrosion that they often cause. Aquatreat® DNM-30 has been found to be especially effective in the control of SRB in both open recirculating and closed cooling water systems.

Figure 12 shows data from a laboratory study in which Aquatreat DNM-30 was used to treat cooling tower sludge. A sludge-in-water sample was treated with an initial dose of 120 ppm of Aquatreat DNM-30, and the number of viable SRB was determined versus time, using an MPN technique. The data show that the initial dose produced a reduction from 105 to 104 SRB/gram of sludge. A subsequent 120 ppm dose of Aquatreat DNM-30 effectively reduced the population to less than 101 SRB/gram of sludge.

Figure 13 shows a field study in which Aquatreat DNM-30 was evaluated for efficacy against planktonic SRB in a closed, chilled-water loop. The number of SRB was counted for five weeks prior to the addition of Aquatreat DNM-30. During week five, a 120 ppm dose of Aquatreat DNM-30 was added to the system. The number of SRB was counted for an additional five weeks after the biocide addition. The data show that a single dosage of Aquatreat DNM-30 effectively lowered the total SRB from 105 SRB/mL to less than 101 SRB/mL.

CFU

/mL

1.00E+07

1.00E+03

1.00E+04

1.00E+05

1.00E+06

0 ppm

91.8%

25 ppm

97.3%50 ppm

Time (H)

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

0 5 10 15 20 25 30

CFU

/mL

1.00E+08

Control (pH 5)

DNM-30 (pH 5)

Control (pH 7)

DNM-30 (pH 7)

Control (pH 9)

DNM-30 (pH 9)

0

50

100

150

200

250

300

350

400


MIC

(pp

m A

ctiv

e)

0

10

100

1,000

10,000

ppm DNM-30 (active)

Leg

ione

lla C

FU/m

L

0 20 60 100

CFU/mL

Hours

1.00E+07

0 20 40 60 80 100 120 140 160

MP

N S

RB

/g S

lud

ge

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06Control


TOTAL ANAEROBES

1.00E+07

1.00E+03

1.00E+04

1.00E+05

1.00E+06

TOTAL SRB

Control

Control

100 ppmDNM-30

100 ppmDNM-30

Time (Weeks)

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

120 ppm DNM-30

0 2 4 6 8 10 12

MP

N S

RB

/mL

Time (H)

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

0 5 10 15 20 25 30

CFU

/mL

or

MP

N/m

L





CFU

/cm

2

Figure 12: Reduction of SRB in Cooling Tower Sludge

CFU

/mL

1.00E+07

1.00E+03

1.00E+04

1.00E+05

1.00E+06

0 ppm

91.8%

25 ppm

97.3%50 ppm

Time (H)

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

0 5 10 15 20 25 30

CFU

/mL

1.00E+08

Control (pH 5)

DNM-30 (pH 5)

Control (pH 7)

DNM-30 (pH 7)

Control (pH 9)

DNM-30 (pH 9)

0

50

100

150

200

250

300

350

400


MIC

(pp

m A

ctiv

e)

0

10

100

1,000

10,000

ppm DNM-30 (active)

Leg

ione

lla C

FU/m

L

0 20 60 100

CFU/mL

Hours

1.00E+07

0 20 40 60 80 100 120 140 160

MP

N S

RB

/g S

lud

ge

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06Control


TOTAL ANAEROBES

1.00E+07

1.00E+03

1.00E+04

1.00E+05

1.00E+06

TOTAL SRB

Control

Control

100 ppmDNM-30

100 ppmDNM-30

Time (Weeks)

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

120 ppm DNM-30

0 2 4 6 8 10 12

MP

N S

RB

/mL

Time (H)

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

0 5 10 15 20 25 30

CFU

/mL

or

MP

N/m

L





CFU

/cm

2

Figure 13: Aquatreat DNM-30 Efficacy for Planktonic SRBs

9

CFU

/mL

1.00E+07

1.00E+03

1.00E+04

1.00E+05

1.00E+06

0 ppm

91.8%

25 ppm

97.3%50 ppm

Time (H)

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

0 5 10 15 20 25 30

CFU

/mL

1.00E+08

Control (pH 5)

DNM-30 (pH 5)

Control (pH 7)

DNM-30 (pH 7)

Control (pH 9)

DNM-30 (pH 9)

0

50

100

150

200

250

300

350

400


MIC

(pp

m A

ctiv

e)

0

10

100

1,000

10,000

ppm DNM-30 (active)

Leg

ione

lla C

FU/m

L

0 20 60 100

CFU/mL

Hours

1.00E+07

0 20 40 60 80 100 120 140 160

MP

N S

RB

/g S

lud

ge

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06Control


TOTAL ANAEROBES

1.00E+07

1.00E+03

1.00E+04

1.00E+05

1.00E+06

TOTAL SRB

Control

Control

100 ppmDNM-30

100 ppmDNM-30

Time (Weeks)

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

120 ppm DNM-30

0 2 4 6 8 10 12

MP

N S

RB

/mL

Time (H)

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

0 5 10 15 20 25 30

CFU

/mL

or

MP

N/m

L





CFU

/cm

2

CFU

/mL

1.00E+07

1.00E+03

1.00E+04

1.00E+05

1.00E+06

0 ppm

91.8%

25 ppm

97.3%50 ppm

Time (H)

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

0 5 10 15 20 25 30

CFU

/mL

1.00E+08

Control (pH 5)

DNM-30 (pH 5)

Control (pH 7)

DNM-30 (pH 7)

Control (pH 9)

DNM-30 (pH 9)

0

50

100

150

200

250

300

350

400


MIC

(pp

m A

ctiv

e)

0

10

100

1,000

10,000

ppm DNM-30 (active)

Leg

ione

lla C

FU/m

L

0 20 60 100

CFU/mL

Hours

1.00E+07

0 20 40 60 80 100 120 140 160

MP

N S

RB

/g S

lud

ge

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06Control


TOTAL ANAEROBES

1.00E+07

1.00E+03

1.00E+04

1.00E+05

1.00E+06

TOTAL SRB

Control

Control

100 ppmDNM-30

100 ppmDNM-30

Time (Weeks)

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

120 ppm DNM-30

0 2 4 6 8 10 12

MP

N S

RB

/mL

Time (H)

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

0 5 10 15 20 25 30

CFU

/mL

or

MP

N/m

L





CFU

/cm

2

Figure 14: Aquatreat DNM-30 Static Cell Death of Attached Bacteria in a Closed Chilled Water Loop (6-hr exposure)

Figure 15: Aquatreat DNM-30 vs. Denitrifying Bacteria

In Figure 14, a Robbins biofilm-monitoring device was installed on a closed, chilled-water loop. After a two-week fouling period, coupons were removed and immersed in a 100 ppm solution of Aquatreat® DNM-30 for six hours. Replicate coupons were removed and immersed in a solution containing no biocide for the same duration. After exposure,the coupons were scraped and evaluated for total aerobic bacteria, anaerobic bacteria and total SRB. The data indicate that Aquatreat DNM-30 effectively lowered the total anaerobic population and was highly effective at killing the SRB contained in the biofilm.

Another group of microorganisms that is often found in closed-loop systems is denitrifying bacteria. These microorganisms are especially prevalent where nitrite inhibitors are used for corrosion control. Their activity not only causes the typical microbial problems but also results in the depletion of the nitrite inhibitor.

Figure 15 shows data from a closed-loop system where nitrite was used for corrosion control. The system pH was buffered to 10.2 using sodiumborate. In this system, nitrite was being depleted due to reduction by denitrifying bacteria. Aquatreat DNM-30 was added to the system, and a significant reduction of total heterotrophic and denitrifying bacteria was observed. The heterotrophic bacteria were enumerated on plate count agar (Difco Laboratories) and denitrifying bacteria were quantified by MPN technique. The data show the pronounced efficacy of Aquatreat DNM-30 for both the heterotrophic and denitrifying populations.

10

Another method of evaluating the efficacy of a treatment program is by quantification of cellular damage after exposure to a biocide. The percentage of cellular damage can be determined by epifluorescent microscopy using a combination of fluorescent dyes. Cells exhibiting a green fluorescence are relatively uninjured, while cells exhibiting an orange to red fluorescence are injured or dead. Using this technique, two chilled water samples from closed-loop systems were treated with Aquatreat® DNM-30. The sample labeled Chilled Water #1 consisted of primary chilled water from a commercial bank operating 24 hours per day. The sample labeled Chilled Water #2 was obtained from a central plant that supplied chilled water to 10 surrounding buildings. The chilled water from this system had not been drained for approximately 20 years and contained dozens of primary and secondary loops. The data in Figure 16 show that Aquatreat DNM-30 has good efficacy in both of these challenging systems after a 12-hour exposure.

Summary of Cooling Tower DataAquatreat DNM-30 is a very effective biocide for problematic microorganisms in both open recirculating and closed cooling water systems. Aquatreat DNM-30 has proven especially effective for the control of anaerobic microorganisms such as SRB and denitrifying bacteria. Additionally, Aquatreat DNM-30 is effective in closed-loop systems because of its stability in reduced or non-oxidizing environments.

All Aquatreat® Biocides are anionic reducing agents. These characteristics provide excellent compatibility with other common additives used for scale and corrosion control.

Because of their reducing characteristics, Aquatreat Biocides should not be fed in close proximity to an oxidizing biocide or in systems where a continuous residual of oxidizing biocide is maintained. In systems where oxidizing biocides are used, Aquatreat Biocides can be an effective treatment on an alternating feed basis.

Aquatreat Biocides are known to complex heavy metals that can be present in cooling water systems. The presence of low levels of heavy metals such as zinc (added for corrosion control) or iron in a cooling water can preclude the use of Aquatreat Biocides. Other additives such as phosphates, azoles, phosphonates and polymers may sufficiently stabilize heavy metals. Aquatreat Biocides are compatible with molybdate (MoO4

2-) containing treatments. Before use in any system, the compatibility of Aquatreat Biocides should be examined using samples from the system’s circulating water. See product label for dosage information.

Figure 16: Cellular Damage in Chilled Water Systems

Benefits of Aquatreat Biocidesin Cooling Water Applications

• Effective control of problematic SRB and denitrifying bacteria

• Excellent compatibility with additives used for scale and corrosion control

• Inherent stability in reducing environments found in closed-loop systems

• Not a persistent biocide

• Effective for a broad range of algae and bacteria

• Low order of toxicity to humans

• Non-foaming

0

5

10

15

20

25

30

35

40

45

50

DNM-30 12-hr. Exposure

% C

ELL

ULA

R D

AM

AG

E

0 ppm120

ppm 0 ppm

CHILLED WATER #1 CHILLED WATER #2

120ppm

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

CFU

/g

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04

Control DNM-30 Quat MBT DBNPA Isothiazolone

CFU

/g



1.00E+02

1.00E+03

1.00E+04

1.00E+05

CFU

/g

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

CFU

/g

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

CFU

/g

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

CFU

/g




11

In paper manufacture, large volumes of water are used in grinding and conveying pulp. The same water is also used as a medium for forming the paper web. This water is recycled throughout the papermaking process and is often a significant source of microbial contamination. The result of contamination can lead to significant problems, such as imperfections or loss of paper, mill downtime and equipment failure. One problem compounding microbial control issues is the use of recycled fiber, which contains a much higher microbial load. An effective biocide must have good microbial control across a range of pH and temperature conditions and exhibit functionality in applications, using both virgin and recycled fiber. Aquatreat® Biocides have proven effective in such systems and are widely used to control slime yeasts and fungi associated with paper mill applications.

Pulp and Paper Applications

Case Study 1Aquatreat DNM-30 has proven cost effective for control of microorganisms associated with fouling in pulp and paper applications. Pulp is digested at relatively high temperatures, and these temperatures are maintained throughout the papermakingprocess. Therefore, a primary group of microorganisms that must be controlled is thermophilic (grown optimally at temperatures above 45°C) bacteria. A study was conducted with samples from a paper mill that was experiencing serious microbial problems. The microbial problems included significant pH reductions in the primary buffer and in the machine stock chest. Excessive slime formation on the wet end was also observed. To solve the problem, several biocides were evaluated in both the virgin and recycled fiber at process temperature. The results are shown in Figures 17-22.

Note for Figures 17-22: Measurements taken after 8 hours of exposure to biocide. Benzalkonium chloride (Quat) was treated at 50 ppm, Aquatreat DMN-30 was treated at 50 ppm, methylene-bis-thiocyanate (MBT) was treated at 20 ppm, dibromonitrilopropionamide (DBNPA) was treated at 50 ppm and isothiazolone was treated at 25 ppm.

Figure 17: Virgin Fiber: Total Acid-Forming Anaerobic Bacteria

Figure 18: Virgin Fiber: Total Anaerobic Bacteria

0

5

10

15

20

25

30

35

40

45

50


% C

ELL

ULA

R D

AM

AG

E

0 ppm120

ppm 0 ppm


120ppm

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

CFU

/g

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04


CFU

/g



1.00E+02

1.00E+03

1.00E+04

1.00E+05

CFU

/g

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

CFU

/g

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

CFU

/g

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

CFU

/gControl DNM-30 Quat MBT DBNPA Isothiazolone



0

5

10

15

20

25

30

35

40

45

50


% C

ELL

ULA

R D

AM

AG

E

0 ppm120

ppm 0 ppm


120ppm

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

CFU

/g

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04


CFU

/g



1.00E+02

1.00E+03

1.00E+04

1.00E+05

CFU

/g

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

CFU

/g

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

CFU

/g

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

CFU

/gControl DNM-30 Quat MBT DBNPA Isothiazolone



12

The data in Figures 17-22 demonstrate that Aquatreat® DNM-30 is a cost-effective biocide in both virgin and recycled fiber. Aquatreat DNM-30 was particularly effective against thermophilic anaerobic bacteria, including those causing the pH reduction in the system.

Case History IIA 650-ton-per-day mill producing clay-coated recycled paperboard was in the process of closing its water system (increasing the use of recycled water and reducing effluent volume). Excess machine whitewater was clarified with a disc saveall. The clarified water from the saveall was used as shower water on the paper machines. The microbial load of the water system had been evaluated on a weekly basis from the start of the recycled water program. Chlorine was applied to the influent water, papermachine stock system and saveall influent. Chlorine residuals were tested on each shift. Shortly after switching to recycled water, total bacterial counts increased 1,000 times and deposit problems began to occur on the paper machine. The deposits were especially prevalent on felt transfer rolls and suction boxes. Deposits periodically broke free and caused sheet breaks. The deposits were analyzed and found to be over 90% microbiological, principally slime. Deposits were also found downstream on the showers that had been converted to recycled water. It was determined that the most cost-effective program would be to treat only the recycled shower water. A biocide evaluation was performed comparing a variety of biocides. Aquatreat DNM-30 was found to have the highest bacterial kill activity in the system and was determined to be the most cost-effective biocide.

Figure 19: Virgin Fiber: Total Aerobic Bacteria

Figure 22: Recycled Fiber: Total Anaerobic Bacteria

Figure 20: Recycled Fiber: Total Acid-Forming Anaerobic Bacteria

Figure 21: Recycled Fiber: Total Aerobic Bacteria

0

5

10

15

20

25

30

35

40

45

50


% C

ELL

ULA

R D

AM

AG

E

0 ppm120

ppm 0 ppm


120ppm

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

CFU

/g

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04


CFU

/g



1.00E+02

1.00E+03

1.00E+04

1.00E+05

CFU

/g

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

CFU

/g

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

CFU

/g

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

CFU

/g




0

5

10

15

20

25

30

35

40

45

50


% C

ELL

ULA

R D

AM

AG

E

0 ppm120

ppm 0 ppm


120ppm

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

CFU

/g

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04


CFU

/g



1.00E+02

1.00E+03

1.00E+04

1.00E+05

CFU

/g

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

CFU

/g

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

CFU

/g

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

CFU

/g




0

5

10

15

20

25

30

35

40

45

50


% C

ELL

ULA

R D

AM

AG

E

0 ppm120

ppm 0 ppm


120ppm

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

CFU

/g

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04


CFU

/g



1.00E+02

1.00E+03

1.00E+04

1.00E+05

CFU

/g

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

CFU

/g

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

CFU

/g

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

CFU

/g




0

5

10

15

20

25

30

35

40

45

50


% C

ELL

ULA

R D

AM

AG

E

0 ppm120

ppm 0 ppm


120ppm

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

CFU

/g

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04


CFU

/g



1.00E+02

1.00E+03

1.00E+04

1.00E+05

CFU

/g

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

CFU

/g

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

CFU

/g

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

CFU

/g




13

After a system boil-out and cleanup, a biological control program using Aquatreat® DNM-30 was initiated. Aquatreat DNM-30 was fed to the discharge side of the shower water supply pump at an initial rate of 80 ppm and later reduced to 50 ppm. Total bacterial counts were reduced by 100 times.

Another significant problem in pulp and paper systems is the growth of yeast and mold. Dithiocarbamates are well known as highly effective fungicides. In Figures 23 and 24, Aquatreat DNM-30 is compared to DBNPA and isothiazolone against mold and yeast. Similar results against fungi have been observed in other applications.

Summary of Pulp and Paper DataAquatreat Biocides should be fed as early as possible into the system at such points as the hydropulper, furnish chest or broke system. Aquatreat Biocides can be used to control slime on machines that make paper and paperboard for use in food packaging regulated under 21 CFR 176.300. Aquatreat Biocides offer the additional advantages of being non-foaming and non-corrosive to equipment. Special feed pumps, gaskets, line feeds and supply systems are not required. Aquatreat Biocides are supplied as aqueous solutions containing no organic solvents. Aquatreat Biocides are safe for systems supplying water to paper machine showers and are not irritating to mill personnel.

Benefits of Aquatreat Biocides in Pulp and Paper Applications

• Effective over a wide pH range

• Effective on slime-forming bacteria, fungi and yeasts

• Meet FDA criteria for use on machines making paper or board for use in food packaging (21 CFR 176.300)

• Non-irritating to personnel

Figure 23: Aquatreat DNM–30 Antifungal Activity

Figure 24: Aquatreat DNM–30 Antifungal Activity Control

DBNPA (25 ppm)

Isothiazolone (25 ppm)

DNM-30 (60 ppm)

Yeast (Candida spp. )

Time (H)

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

0 5 10 15 20 25 30

CFU

/mL

Time (H)

1.00E+04

1.00E+05

1.00E+06

0 5 10 15 20 25 30

CFU

/mL

Control

DBNPA (25 ppm)


DNM-30 (60 ppm)

Mold ( Aspergillus niger )

40

80

120

160

200

CompetitiveProduct A*

Hours0 20 40 60

(g/L

)

DNM-30 (20 ppm)

Control

*DISODIUM CYANODITHIOIMIDOCARBONATE + POTASSIUM N-METHYLDITHIOCARBAMATE

3

4

5

6

7

pH


DNM-30 (20 ppm)

Control

0.0

0.1

0.2

0.3

0.4

0.5

Co

ncen

trat

ion

(g/L

)


DNM-30 (20 ppm)

Control

Hours0 20 40 60


Hours0 20 40 60


Control

DBNPA (25 ppm)


DNM-30 (60 ppm)


Time (H)

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

0 5 10 15 20 25 30

CFU

/mL

Time (H)

1.00E+04

1.00E+05

1.00E+06

0 5 10 15 20 25 30

CFU

/mL

Control

DBNPA (25 ppm)


DNM-30 (60 ppm)


40

80

120

160

200


Hours0 20 40 60

(g/L

)

DNM-30 (20 ppm)

Control


3

4

5

6

7

pH


DNM-30 (20 ppm)

Control

0.0

0.1

0.2

0.3

0.4

0.5

Co

ncen

trat

ion

(g/L

)


DNM-30 (20 ppm)

Control

Hours0 20 40 60


Hours0 20 40 60


14

Sugar ApplicationsBeet and Cane SugarDithiocarbamate biocides such as Aquatreat® DNM-30 are among the few products approved by both EPA and FDA for sugar production. Microorganisms account for significant product loss, prolific formation of biofilms, organic acid formation, pH drops and equipment corrosion. These problems are caused by both mesophillic (optimal growth between 22° and 44°C) and thermophilic bacteria that enter with the beet or cane stock and proliferate throughout the system. These bacteria are largely comprised of spore-forming organisms such as Bacillus and Clostridium spp. and a number of lactic acid bacteria (i.e., Leuconostoc and Lactobacillus). Aquatreat® Biocides have a long history of demonstrated efficacy in both cane and beet sugar mills.

Laboratory StudiesLaboratory studies demonstrate the functionality of Aquatreat DNM-30 for use in the treatment of a beet sugar system. In these studies, fresh samples of raw recirculating juice were incubated across time at 55°C. During incubation, aliquots were taken and analyzed for total sugar, total lactic acid and pH. Figures 26-28 show a comparison of Aquatreat DNM-30 with a competitive biocide for their relative ability to maintain total sugar content in circulating raw juice, limit pH reduction and suppress lactic acid formation. Aquatreat DNM-30 shows superior efficacy relative to the competitive material.

Control

DBNPA (25 ppm)


DNM-30 (60 ppm)


Time (H)

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

0 5 10 15 20 25 30

CFU

/mL

Time (H)

1.00E+04

1.00E+05

1.00E+06

0 5 10 15 20 25 30

CFU

/mL

Control

DBNPA (25 ppm)


DNM-30 (60 ppm)


40

80

120

160

200


Hours0 20 40 60

(g/L

)

DNM-30 (20 ppm)

Control


3

4

5

6

7

pH


DNM-30 (20 ppm)

Control

0.0

0.1

0.2

0.3

0.4

0.5

Co

ncen

trat

ion

(g/L

)


DNM-30 (20 ppm)

Control

Hours0 20 40 60


Hours0 20 40 60


Control

DBNPA (25 ppm)


DNM-30 (60 ppm)


Time (H)

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

0 5 10 15 20 25 30

CFU

/mL

Time (H)

1.00E+04

1.00E+05

1.00E+06

0 5 10 15 20 25 30

CFU

/mL

Control

DBNPA (25 ppm)


DNM-30 (60 ppm)


40

80

120

160

200


Hours0 20 40 60

(g/L

)

DNM-30 (20 ppm)

Control


3

4

5

6

7

pH


DNM-30 (20 ppm)

Control

0.0

0.1

0.2

0.3

0.4

0.5

Co

ncen

trat

ion

(g/L

)


DNM-30 (20 ppm)

Control

Hours0 20 40 60


Hours0 20 40 60


Control

DBNPA (25 ppm)


DNM-30 (60 ppm)


Time (H)

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

0 5 10 15 20 25 30

CFU

/mL

Time (H)

1.00E+04

1.00E+05

1.00E+06

0 5 10 15 20 25 30

CFU

/mL

Control

DBNPA (25 ppm)


DNM-30 (60 ppm)


40

80

120

160

200


Hours0 20 40 60

(g/L

)

DNM-30 (20 ppm)

Control


3

4

5

6

7

pH


DNM-30 (20 ppm)

Control

0.0

0.1

0.2

0.3

0.4

0.5

Co

ncen

trat

ion

(g/L

)


DNM-30 (20 ppm)

Control

Hours0 20 40 60


Hours0 20 40 60


Figure 26: Total Sugar Concentration

Figure 27: System pH

Figure 28: Lactic Acid

15

Field StudiesBeet Sugar Field Study I

A beet sugar production factory in California employs a 5,000-ton tower diffuser system. The normal chemical treatment before this trial was a shock dose of formaldehyde. No formaldehyde was added in the seven days prior to this trial. Six samples were selected for monitoring. These samples included:

• Raw juice leaving cossette mixer• Circulation juice before heaters• Bottom of diffuser• Middle of diffuser• Top of diffuser• Pulp press water at the screens

Initial sampling was conducted prior to the addition of Aquatreat® DNM-30 at a rate of 10 ppm/kg beets. In addition, the spray water at the separator rolls also received 8 pounds of Aquatreat DNM-30 per 1,000 tons of beets. Samples were collected at the indicated process points across a 72-hour period. The results of the testing are shown in Figures 29-32. At all sample points, a clear reduction in total thermophilic bacteria was observed. Across the 72 hours of the trial, a significant reduction in lacticacid formation was also observed.

Figure 29: Thermophilic Bacteria Counts

Figure 30: Lactic Acid Concentration in Diffuser Samples

Figure 32: Lactic Acid Concentration in Juice and Water Samples

Figure 31: Thermophilic Bacteria Counts in Juice and Water Samples

Hours0 20 40 60

Top

65° C

66° C

70° CMiddle

Bottom

100

101

102

103

104

80

CFU

/mL

0

50

100

150

200

250

300

Co

ncen

trat

ion

(mg

/L)

Press Water

Circulating Juice

Raw Juice

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04

Co

ncen

trat

ion

(CFU

/mL)

Press Water

Circulating Juice

Raw Juice45° C

72° C

66° C

Co

ncen

trat

ion

(mg

/L)

Top

Middle

Bottom

0

50

100

150

200

250

Hours0 20 40 60 80

Hours

0 20 40 60 80

Hours

0 20 40 60 80

Days0

Co

ncen

trat

ion

CFU

/g

Mesophiles

pHThermophiles

1.00E+08

8

1.00E+07

1.00E+05

1.00E+04

1.00E+03

1.00E+02

1.00E+06

8

4

6

5.5

6.5

5

7

4.5

7.5ClO2 DNM-30

(20 ppm)

ClO2

Hours0

Co

ncen

trat

ion

(CFU

/mL

x 10

6 )

% S

ugar

2 4 6 8 102

3

4

5

6

7

8

9

76

78

80

82

84

12

Total Bacteria

Leuconostoc

Percent Sugar

Time (h)0

CP

U/m

L o

r M

PN

SR

B/m

L

20 40 60 80 100 120 140 160 1801.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

Controls

SRB (60 ppm) DNM-30

Injection Water (pH = 6.3)+200 ppm Fe

Heterotrophs120 ppm DNM-30

60 ppm DNM-30{

Hours0 20 40 60

Top

65° C

66° C

70° CMiddle

Bottom

100

101

102

103

104

80

CFU

/mL

0

50

100

150

200

250

300

Co

ncen

trat

ion

(mg

/L)

Press Water

Circulating Juice

Raw Juice

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04

Co

ncen

trat

ion

(CFU

/mL)

Press Water

Circulating Juice

Raw Juice45° C

72° C

66° C

Co

ncen

trat

ion

(mg

/L)

Top

Middle

Bottom

0

50

100

150

200

250

Hours0 20 40 60 80

Hours

0 20 40 60 80

Hours

0 20 40 60 80

Days0

Co

ncen

trat

ion

CFU

/g

Mesophiles

pHThermophiles

1.00E+08

8

1.00E+07

1.00E+05

1.00E+04

1.00E+03

1.00E+02

1.00E+06

8

4

6

5.5

6.5

5

7

4.5

7.5ClO2 DNM-30

(20 ppm)

ClO2

Hours0

Co

ncen

trat

ion

(CFU

/mL

x 10

6 )

% S

ugar

2 4 6 8 102

3

4

5

6

7

8

9

76

78

80

82

84

12

Total Bacteria

Leuconostoc

Percent Sugar

Time (h)0

CP

U/m

L o

r M

PN

SR

B/m

L

20 40 60 80 100 120 140 160 1801.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

Controls

SRB (60 ppm) DNM-30



60 ppm DNM-30{

Hours0 20 40 60

Top

65° C

66° C

70° CMiddle

Bottom

100

101

102

103

104

80

CFU

/mL

0

50

100

150

200

250

300

Co

ncen

trat

ion

(mg

/L)

Press Water

Circulating Juice

Raw Juice

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04

Co

ncen

trat

ion

(CFU

/mL)

Press Water

Circulating Juice

Raw Juice45° C

72° C

66° C

Co

ncen

trat

ion

(mg

/L)

Top

Middle

Bottom

0

50

100

150

200

250

Hours0 20 40 60 80

Hours

0 20 40 60 80

Hours

0 20 40 60 80

Days0

Co

ncen

trat

ion

CFU

/g

Mesophiles

pHThermophiles

1.00E+08

8

1.00E+07

1.00E+05

1.00E+04

1.00E+03

1.00E+02

1.00E+06

8

4

6

5.5

6.5

5

7

4.5

7.5ClO2 DNM-30

(20 ppm)

ClO2

Hours0

Co

ncen

trat

ion

(CFU

/mL

x 10

6 )

% S

ugar

2 4 6 8 102

3

4

5

6

7

8

9

76

78

80

82

84

12

Total Bacteria

Leuconostoc

Percent Sugar

Time (h)0

CP

U/m

L o

r M

PN

SR

B/m

L

20 40 60 80 100 120 140 160 1801.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

Controls

SRB (60 ppm) DNM-30



60 ppm DNM-30{

Hours0 20 40 60

Top

65° C

66° C

70° CMiddle

Bottom

100

101

102

103

104

80

CFU

/mL

0

50

100

150

200

250

300

Co

ncen

trat

ion

(mg

/L)

Press Water

Circulating Juice

Raw Juice

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04

Co

ncen

trat

ion

(CFU

/mL)

Press Water

Circulating Juice

Raw Juice45° C

72° C

66° C

Co

ncen

trat

ion

(mg

/L)

Top

Middle

Bottom

0

50

100

150

200

250

Hours0 20 40 60 80

Hours

0 20 40 60 80

Hours

0 20 40 60 80

Days0

Co

ncen

trat

ion

CFU

/g

Mesophiles

pHThermophiles

1.00E+08

8

1.00E+07

1.00E+05

1.00E+04

1.00E+03

1.00E+02

1.00E+06

8

4

6

5.5

6.5

5

7

4.5

7.5ClO2 DNM-30

(20 ppm)

ClO2

Hours0

Co

ncen

trat

ion

(CFU

/mL

x 10

6 )

% S

ugar

2 4 6 8 102

3

4

5

6

7

8

9

76

78

80

82

84

12

Total Bacteria

Leuconostoc

Percent Sugar

Time (h)0

CP

U/m

L o

r M

PN

SR

B/m

L

20 40 60 80 100 120 140 160 1801.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

Controls

SRB (60 ppm) DNM-30



60 ppm DNM-30{

16

Hours0 20 40 60

Top

65° C

66° C

70° CMiddle

Bottom

100

101

102

103

104

80

CFU

/mL

0

50

100

150

200

250

300

Co

ncen

trat

ion

(mg

/L)

Press Water

Circulating Juice

Raw Juice

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04

Co

ncen

trat

ion

(CFU

/mL)

Press Water

Circulating Juice

Raw Juice45° C

72° C

66° C

Co

ncen

trat

ion

(mg

/L)

Top

Middle

Bottom

0

50

100

150

200

250

Hours0 20 40 60 80

Hours

0 20 40 60 80

Hours

0 20 40 60 80

Days0

Co

ncen

trat

ion

CFU

/g

Mesophiles

pHThermophiles

1.00E+08

8

1.00E+07

1.00E+05

1.00E+04

1.00E+03

1.00E+02

1.00E+06

8

4

6

5.5

6.5

5

7

4.5

7.5ClO2 DNM-30

(20 ppm)

ClO2

Hours0

Co

ncen

trat

ion

(CFU

/mL

x 10

6 )

% S

ugar

2 4 6 8 102

3

4

5

6

7

8

9

76

78

80

82

84

12

Total Bacteria

Leuconostoc

Percent Sugar

Time (h)0

CP

U/m

L o

r M

PN

SR

B/m

L

20 40 60 80 100 120 140 160 1801.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

Controls

SRB (60 ppm) DNM-30



60 ppm DNM-30{

Cane Sugar Study IThis factory processes 3,000 tons of beets per day and alternates biocide use between chlorine dioxide and Aquatreat® DNM-30. Both biocides were added alternately to the press pulp water prior to entering the diffuser. The biocides were applied at a concentration of 20 mg/kg beet. Over an eight-day period, the diffuser juice was monitored for totalmesophilic and thermophilic bacteria. The results are presented in Figure 33. The data show that Aquatreat DNM-30 provided an equal level of control of total thermophiles and significantly better control of total mesophiles throughout the duration of the trial.

Cane Sugar Mill Study IIThis cane sugar mill processed 3,000 tons per day of sugar cane using mill tandems. Raw cane was washed to remove solids prior to crushing in the first two crushers. The extracted juice, known as “crusher juice,” contains upwards of 80% sucrose. Cane continues through the tandem mills where more sugar is extracted. The juice from each mill is recirculated to an earlier mill. All the juices were then combined to form the “dilute juice.” The troublesome organism in this system was Leuconostoc mesenteroides, which is responsible for significant sugar inversion and aggressive slime formation.

Aquatreat DNM-30 was applied to this system at a rate of 20 ppm or about 34 mL/min based on 3,000 tons/day. The effectiveness of control was determined by measuring Leuconostoc counts in sucrose gelatin agar and by analysis of sucrose levels. The results presented in Figure 34 indicate that (at the concentration used) the Aquatreat DNM-30 at 20 ppm acts primarily as a bacteriostat preventing multiplication of the bacteria.

Summary of Sugar DataLaboratory and field studies have demonstrated that Aquatreat DNM-30 is effective in controlling bacteria associated with both cane and beetsugar manufacturing. In addition, the low relative cost of Aquatreat DNM-30 and its ability to reduce sugar loss and control organic acid production and pH make it an excellent biocide for such applications.

Figure 34: Cane Sugar “Crusher Juice” DNM-30 (20 ppm)

Figure 33: Diffuser Samples

17

Benefits of Aquatreat® Biocidesin Sugar Applications

• EPA registered

• Meet FDA criteria under 176.320

• Effective against difficult-to-treat thermophilic, spore-forming bacteria

• Reduces sugar loss and organic acid formation

• Cost effective at typical use levels

18

Oil Field ApplicationsSecondary and Tertiary Oil RecoveryIn some oil recovery operations, water is injected into the ground under high pressure to force residual crude oil toward a producing well. The water is forced through the very small pores of the core rock formation. Any bacterial growth in this water will tend to block pores in the formation, rendering the process far less efficient. Additionally, bacteria, such as SRB, produce by-products that cause significant corrosion of pipe and equipment.

In these injection systems, Aquatreat® Biocides are highly effective for enhanced oil recovery (EOR) and water floods. They are used in both secondary and tertiary recovery because of their stability in the presence of oxygen scavengers and their non-corrosive characteristics. Aquatreat Biocides are nonaldehyde products with broad activity against both aerobes and anaerobes yet have a low order of toxicity to humans. They are very cost effective when compared with isothiazolone compounds because they are more active, cost less per pound, are saferand exhibit control over a longer period.

The activity of Aquatreat DNM-30 has been demonstrated using the American Petroleum Institute (API) RP-39 MIC test. The test was amended to include a broad spectrum of SRB, including both cataloged strains and oil field injection water isolates. Table 6 shows that Aquatreat DNM-30 is very effective against many types of SRB at use concentrations.

Aquatreat DNM-30 has been evaluated in a number of oil field injection waters. In Figure 35, a sample from a Wyoming secondary flood projectwith a significantly high iron content was treated with Aquatreat DNM-30, and the total heterotrophic and SRB were followed across time. The data show good control over total heterotrophic bacteria and excellent activity against SRB.

Hours0 20 40 60

Top

65° C

66° C

70° CMiddle

Bottom

100

101

102

103

104

80

CFU

/mL

0

50

100

150

200

250

300

Co

ncen

trat

ion

(mg

/L)

Press Water

Circulating Juice

Raw Juice

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04

Co

ncen

trat

ion

(CFU

/mL)

Press Water

Circulating Juice

Raw Juice45° C

72° C

66° C

Co

ncen

trat

ion

(mg

/L)

Top

Middle

Bottom

0

50

100

150

200

250

Hours0 20 40 60 80

Hours

0 20 40 60 80

Hours

0 20 40 60 80

Days0

Co

ncen

trat

ion

CFU

/g

Mesophiles

pHThermophiles

1.00E+08

8

1.00E+07

1.00E+05

1.00E+04

1.00E+03

1.00E+02

1.00E+06

8

4

6

5.5

6.5

5

7

4.5

7.5ClO2 DNM-30

(20 ppm)

ClO2

Hours0

Co

ncen

trat

ion

(CFU

/mL

x 10

6 )

% S

ugar

2 4 6 8 102

3

4

5

6

7

8

9

76

78

80

82

84

12

Total Bacteria

Leuconostoc

Percent Sugar

Time (h)0

CP

U/m

L o

r M

PN

SR

B/m

L

20 40 60 80 100 120 140 160 1801.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

Controls

SRB (60 ppm) DNM-30



60 ppm DNM-30{

Figure 35: Aquatreat DNM-30 in Injection Water

Table 6: Sulfur-Reducing Bacteria—Laboratory Pure Cultures and Enrichments

Sulfate-reducer Source Enrichment System MIC (ppm)

Desulfovibrio spp. ATCC 7757 Med-42 20-25

Desulfovibrio spp. Oil field Injection Water (New Mexico) Postgate E 65-70

Desulfovibrio spp. Oil field Injection Water (New Mexico) API-sulfate 15-20

Desulfovibrio spp. Oil field Injection Water (SW Texas) API-sulfate 55-60

Desulfobacter spp. ATCC 43913 Med 1648 45-50

Desulfomonile spp. ATCC 49306 Med 1690 20-25

Desulfococcus spp. ATCC 33890 Med 1250 120-130

19

In Figures 36 and 37, the activity of Aquatreat® DNM-30 is compared with a cocodiamine product in two additional injection waters. The control of aerobic heterotrophic bacteria was monitored across time. The data again show excellent activity of Aquatreat DNM-30 relative to the competitive biocide.

Figure 37: Injection Water Samples: Sample 2

Time (h)0

CFU

/mL

10 20 30 40 50 80701.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

60

Control

CDA (30)

DNM-30 (120)

Time in Hours

To

tal S

RB

Co

unts

/mL

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

20 4 6 8 12 24

No Sulfite

100 ppm Sulfite

Time (h)0

CFU

/mL

5 10 15 20 251.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08Control 3.4%

Control 6.8%

DNM-30 in 3.4%

DNM-30 in 6.8%

Time (h)0

SR

B/m

L

2 4 8 121.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

Control in 3.4%

Control in 6.8%

DNM-30 in 3.4%

24

DNM-30 in 6.8%

Time (h)0

CFU

/mL

10 20 30 40 50 80701.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

60

Control

CDA (30)

DNM-30 (120)

Time (h)0

CFU

/mL

10 20 30 40 50 80701.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

60

Control

CDA (30)

DNM-30 (120)

Time in Hours

To

tal S

RB

Co

unts

/mL

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

20 4 6 8 12 24

No Sulfite

100 ppm Sulfite

Time (h)0

CFU

/mL

5 10 15 20 251.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07


Control 6.8%

DNM-30 in 3.4%

DNM-30 in 6.8%

Time (h)0

SR

B/m

L

2 4 8 121.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

Control in 3.4%

Control in 6.8%

DNM-30 in 3.4%

24

DNM-30 in 6.8%

Time (h)0

CFU

/mL

10 20 30 40 50 80701.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

60

Control

CDA (30)

DNM-30 (120)

Figure 36: Injection Water Samples: Sample 1

Time (h)0

CFU

/mL

10 20 30 40 50 80701.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

60

Control

CDA (30)

DNM-30 (120)

Time in Hours

To

tal S

RB

Co

unts

/mL

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

20 4 6 8 12 24

No Sulfite

100 ppm Sulfite

Time (h)0

CFU

/mL

5 10 15 20 251.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07


Control 6.8%

DNM-30 in 3.4%

DNM-30 in 6.8%

Time (h)0

SR

B/m

L

2 4 8 121.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

Control in 3.4%

Control in 6.8%

DNM-30 in 3.4%

24

DNM-30 in 6.8%

Time (h)0

CFU

/mL

10 20 30 40 50 80701.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

60

Control

CDA (30)

DNM-30 (120)

Figure 38: Aquatreat DMN-30 in the Presence of Sulfite

Aquatreat DNM-30 can be used in injection water systems where only short contact time is possible and where more rapid control must be established with slug doses, as opposed to continuous feed. In a study to demonstrate this effect, SRB levels were reduced significantly in the presence of a sulfite oxygen scavenger. Figure 38 shows the effect using 300 ppm of Aquatreat DNM-30. For such systems, Aquatreat DNM-30 should be added after sulfite addition.

20

Time (h)0

CFU

/mL

10 20 30 40 50 80701.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

60

Control

CDA (30)

DNM-30 (120)

Time in Hours

To

tal S

RB

Co

unts

/mL

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

20 4 6 8 12 24

No Sulfite

100 ppm Sulfite

Time (h)0

CFU

/mL

5 10 15 20 251.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07


Control 6.8%

DNM-30 in 3.4%

DNM-30 in 6.8%

Time (h)0

SR

B/m

L

2 4 8 121.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

Control in 3.4%

Control in 6.8%

DNM-30 in 3.4%

24

DNM-30 in 6.8%

Time (h)0

CFU

/mL

10 20 30 40 50 80701.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

60

Control

CDA (30)

DNM-30 (120)

Figure 39: Aquatreat DMN-30 Efficacy in Brines: Heterotrophs

Figure 40: Aquatreat DMN-30 Efficacy in Brines: Sulfate-Reducing Bacteria

Time (h)0

CFU

/mL

10 20 30 40 50 80701.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

60

Control

CDA (30)

DNM-30 (120)

Time in Hours

To

tal S

RB

Co

unts

/mL

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

20 4 6 8 12 24

No Sulfite

100 ppm Sulfite

Time (h)0

CFU

/mL

5 10 15 20 251.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07


Control 6.8%

DNM-30 in 3.4%

DNM-30 in 6.8%

Time (h)0

SR

B/m

L

2 4 8 121.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

Control in 3.4%

Control in 6.8%

DNM-30 in 3.4%

24

DNM-30 in 6.8%

Time (h)0

CFU

/mL

10 20 30 40 50 80701.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

60

Control

CDA (30)

DNM-30 (120)

Benefits of Aquatreat Biocidesin Oil Applications

• Effective against anaerobic bacteria such as SRBs

• Stable and effective in the presence of oxygen scavengers

• Non-corrosive

• Low order of toxicity to humans

• Cost effective at typical use levels

• Exhibits effective control over a long use period

Efficacy in BrinesBiocides are frequently used in oil field systems that contain brines and must maintain their activity under these conditions. As can be seen in Figures 39 and 40, Aquatreat® DNM-30 maintains its efficacy for both heterotrophic bacteria and SRB in seawater brine solutions.

Drilling and Well Completion FluidsWater-based drilling fluids are complex aqueous mixtures of specialty clays, starches, water retention agents, thinners and other ingredients. These fluids are subjected to extremes in pressure, shear and temperature as they are recirculated between the drill bit and surface.

Water-based completion fluids are highly sophisticated systems based on organic polymers, sand and suspending and crosslinking agents. Like drilling fluids, they are subjected to extremes in pressure, shear and temperature.

Recirculation and exposure of drilling and well completion fluids to subsurface conditions can promote bacterial growth. Unchecked, bacteria will degrade the fluids and generate corrosive agents and odors. To inhibit growth, a variety of biocides have been used. Aquatreat Biocides offer a safe and cost-effective choice for use in drilling and well completion fluids.

21

Comparative Fluid Loss TestOne of the most important functions of a drilling mud is to maintain fluid control. Aquatreat® DNM-30 and Aquatreat KM were compared with two different aldehyde-based biocides for API fluid loss control. A base mud was prepared by adding to tap water 7.5 pounds per barrel ofbentonite clay while stirring, followed by 3.5 pounds per barrel of attapulgite clay. After the clays were hydrated, 4.0 pounds per barrel of starch were added to the slurry. The base mud was then divided into 350 cc aliquots, and biocide was added as indicated. The base muds were subjected to conditions that would simulate field conditions. The results in Table 7 show that both Aquatreat Biocides were effective throughout the 14-day test period.

API FLUID LOSS (mL) Days

Treatment Compound Amount Pounds/bbl 1 3 5 7 9 14

Blank Mud0

6.1 8.3 13.7 28.0 37.0 45.0

pH 8.3 10.1 8.2 8.1 8.0 7.9

Aquatreat DNM-30.25 as is

6.8 7.3 7.9 9.8 12.0 17.1

pH 8.2 10.4 8.5 8.3 8.2 8.2

Aquatreat KM.25 as is

6.9 7.5 7.9 10.1 13.1 19.2

pH 8.3 10.3 8.4 8.4 8.3 8.2

Paraformaldehyde (dry).25 as is

5.0 6.2 8.7 9.1 10.1 14.0

pH 8.3 10.1 8.2 8.1 8.0 8.0

Aldehyde-type (25%)1.0 as is

6.4 7.4 10.5 11.5 12.9 21.0

pH 8.3 10.1 8.1 8.0 8.0 8.0

Table 7: Fluid Loss vs. Time

Mud Rheology CharacteristicsMud rheology is a critical property that must be maintained throughout the drilling process. Unchecked bacterial growth will significantly alter these properties and reduce mud effectiveness. Aquatreat DNM-30 has been demonstrated to effectively control bacteria that may impact rheological properties. This is demonstrated in Tables 8, 9 and 10 and compared with paraformaldehyde.

22

Days Int. 1 2 4 6 7 8 12 15 19

Fann Data

600 rpm 12 10 11 10 11 12 13 12 11 9

300 rpm 8 7 7 8 8 9 9 8 8 5

AV. cps 6 4 5.5 5 5.5 6 6.5 6 5.5 4.5

PV. cps 4 3 4 2 3 3 4 4 3 4

YP. #/100 ft2 4 4 3 6 5 6 5 4 5 1

10 Sec. Gel 2 2 3 3 5 5 5 3 4 1

10 Min. Gel 4 3 4 5 5 5 4 4 4 2

pH 8.5 8.5 8.2 7.7 7.6 7.0 6.6 6.5 6.3 5.7

API F.L. 10.5 10.5 13.0 44.0 55.0 55.0 56.5 58.5 59.1 60.0

Days Int. 1 2 3 6 7 8 9 13

Fann Data

600 rpm 12 12 12 11 11 10 11 10 11

300 rpm 8 9 9 8 8 7 8 8 8

AV. cps 6 6 6 5.5 5.5 5 5.5 5 5.5

PV. cps 4 3 3 3 3 3 3 2 3

YP. #/100 ft2 4 6 6 5 5 4 5 6 5

10 Sec. Gel 2 2 3 2 2 2 3 3 4

10 Min. Gel 5 4 3 4 4 4 4 4 4

pH 8.5 8.5 8.5 8.6 8.5 8.6 8.5 8.2 8.1

API F.L. 9.0 9.0 9.0 9.0 9.0 9.4 9.6 9.8 15.2

Days Int. 1 2 3 6 7 8 9 13 16

Fann Data

600 rpm 13 12 11 11 10 10 10 10 10 10

300 rpm 9 8 8 8 8 7 7 7 7 7

AV. cps 6.5 6 5.5 5.5 5 5 5 5 5 5

PV. cps 4 4 3 3 2 3 3 3 3 3

YP. #/100 ft2 5 4 5 5 6 4 4 4 4 4

10 Sec. Gel 4 3 4 3 2 3 2 2 3 3

10 Min. Gel 5 5 3 3 3 4 4 3 4 4

pH 8.5 8.5 8.6 8.7 8.5 8.6 8.5 8.5 8.2 8.3

API F.L. 9.5 10.0 10.0 10.5 11.0 10.8 11.0 12.0 14.0 16.0

Table 8: Base Mud* — No Biocide

Table 9: Aquatreat DNM-30 — .25#/bbl — 30% Solids

* Base mud was prepared by adding to tap water 7.5 pounds per barrel of bentonite clay while stirring, followed by 3.5 pounds per barrel of attapulgite clay. After the clays were hydrated, 3.0 pounds per barrel of cornstarch were added. Two pounds per barrel of topsoil were added to each mud.

Table 10: Paraformaldehyde — .25#/bbl

23

Storage and HandlingAquatreat® products are available in bulk, intermediate bulk and 55-gal-lon drums. The standard drum is fiber with 525 pounds net. Plastic drums are also available. Aquatreat polymers have very low toxicity. Consult product MSDS for further information. Contact with the skin or eyes should be avoided. If an Aquatreat product contacts the eyes, flush with water. If redness or sensitivity occurs and persists, consult a physician. Aquatreat polymers should be shipped and stored in 304 stainless steel or better, fiberglass or plastic tanks. Certain phenolic linings are acceptable for use in drums and storage tanks. Mild steel, copper, brass and aluminum should not be used. The above materials of construction also apply to all pipes, valves and pumps used in the application or transport of Aquatreat polymers.

Environmental HazardsThis pesticide is toxic to fish. Do not apply (or use) in estuarine oil fields where drilling fluids (muds) are discharged in the surface water. Do not contaminate water by cleaning of equipment or disposal of wastes. Do not discharge effluent containing this product into lakes, streams, ponds, estuaries, oceans or other waters unless in accordance with the requirements of a National Pollutant Discharge Elimination System (NPDES) permit and the permitting authority has been notified in writing prior to discharge. Do not discharge effluent containing this product to sewer systems without previously notifying the local sewage treatment plant authority. For guidance, contact your State Water Board or Regional Office of the EPA.

Storage and Disposal1. PROHIBITIONS: Do not contaminate water, food or feed by storage

or disposal. Open dumping prohibited.

2. PESTICIDE DISPOSAL: Pesticide wastes are toxic. Improper disposal of excess pesticide, spray mixture or rinsate is a violation of federal law. If these wastes cannot be disposed of by use according to label instructions, contact your state pesticide or environmental control agency, or the hazardous waste representative at the nearest EPA regional office for guidance.

3. CONTAINER DISPOSAL:(a) Reseal container and offer for reconditioning, or(b) Metal Containers: Triple rinse (or equivalent). Then offer for recycling

or reconditioning, or puncture and dispose of in a sanitary landfill or by other approved state and local procedures.

(c) Plastic containers: Triple rinse (or equivalent). Then offer for recycling or reconditioning, or puncture and dispose of in a sanitary landfill, or incineration, or if allowed by state and local authorities, by burning. If burned, stay out of smoke.

4. GENERAL: Consult federal, state or local disposal authorities for approved alternative procedures.

Statement of Practical TreatmentKEEP OUT OF REACH OF CHILDREN

First AidIF IN EYES- Hold eye open and rinse slowly and gently with water for 15–20 minutes.- Remove contact lenses, if present, after the first 5 minutes, then

continue rinsing eye.- Call a poison control center or doctor for treatment advice.

IF ON SKIN OR CLOTHING- Take off contaminated clothing.- Rinse skin immediately with plenty of water for 15–20 minutes.- Call a poison control center or doctor for treatment advice.

IF SWALLOWED- Call a poison control center or doctor immediately for treatment advice.- Have person sip a glass of water if able to swallow.- Do not induce vomiting unless told to do so by the poison control center

or doctor.- Do not give anything by mouth to an unconscious person.

IF INHALED- Move person to fresh air.- If person is not breathing, call 911 or an ambulance, then give artificial

respiration, preferably by mouth-to-mouth, if possible.- Call a poison control center or doctor for further treatment advice.

HOT LINE NUMBERHave the product container or label with you when calling a poison control center or doctor, or going for treatment.

You may also call 1-888-456-6218 day or night for emergency medical treatment information.

Brazil and South AmericaAkzo Nobel Ltda Divisão QuímicaRodovia AkzoNobel 707Bairro São Roque da ChaveZip Code: 13.295-000Itupeva, São PauloBrazilTel: +55 11 4591 8939Fax: +55 11 4591 1744Email: [email protected]

US, Canada and MexicoAkzo Nobel Surface Chemistry LLC525 West Van Buren StreetChicago, IL 60607-3823United States of AmericaTel: 312 544 7000Fax: 312 544 7410Email: [email protected]

Europe, Africa and Middle EastAkzo Nobel Surface Chemistry ABStenunge Allé 3SE-444 85 StenungsundSwedenTel: +46 303 85000Fax: +46 303 84659Email: [email protected]

Asia-PacificAkzoNobel Surface Chemistry22F, Eco City, No. 1788 West Nan Jing Road, Shanghai, 200040 ChinaTel: +86 21 2220 5000Fax: +86 21 2220 5558

AkzoNobel Surface Chemistry3 Changi Business Park Vista, #05-01Singapore 486051Tel: +65 66355183Fax: +65 66355327

A L L I N F O R M AT I O N C O N C E R N I N G T H E S E P R O D U C T S A N D / O R A L L S U G G E S T I O N S F O R H A N D L I N G A N D U S E C O N TA I N E D H E R E I N A R E O F F E R E D I N G O O D FA I T H A N D B E L I E v E D T O B E R E L I A B L E . A K z O N O B E L S U R FA C E C H E M I S T RY L L C A N D I T S A F F I L I AT E S , H O W E v E R , M A K E N O WA R R A N T Y A S T O T H E A C C U R A C Y A N D /O R S U F F I C I E N C Y O F S U C H I N F O R M AT I O N A N D / O R S U G G E S T I O N S , A S T O T H E P R O D U C T S ’ M E R C H A N TA B I L I T Y O R F I T N E S S F O R A N Y PA RT I C U L A R P U R P O S E , O R T H AT A N Y S U G G E S T E D U S E W I L L N O T I N F R I N G E A N Y PAT E N T. N O T H I N G C O N TA I N E D H E R E I N S H A L L B E C O N S T R U E D A S G R A N T I N G O R E x T E N D I N G A N Y L I C E N S E U N D E R A N Y PAT E N T. B U Y E R M U S T D E T E R M I N E F O R H I M S E L F, B Y P R E L I M I N A RY T E S T S O R O T H E RW I S E , T H E S U I TA B I L I T Y O F T H E S E P R O D U C T S F O R H I S P U R P O S E S . T H E I N F O R M AT I O N C O N TA I N E D H E R E I N S U P E R S E D E S A L L P R E v I O U S LY I S S U E D B U L L E T I N S O N T H E S U B j E C T M AT T E R C O v E R E D . T H E U S E R M AY F O RWA R D , D I S T R I B U T E A N D / O R P H O T O C O P Y T H I S D O C U M E N T O N LY I F U N A LT E R E D A N D C O M P L E T E , I N C L U D I N G A L L O F I T S H E A D E R S A N D F O O T E R S , A N D S H O U L D R E F R A I N F R O M A N Y U N A U T H O R I z E D U S E . Y O U M AY N O T C O P Y T H I S D O C U M E N T T O A W E B S I T E .

© 2 0 1 0 A K z O N O B E L S U R FA C E C H E M I S T RY L L C 5 3 0 1 - 0 1 - 0 8 0 7 - 1 0 M

For more information on our portfolio of technologies for industrial water treatment applications, visit our website at http://www.akzonobel.com/surface/markets/water_treatment/

Documents

AkzoNobel Tb Aquatreat Biocides-1