Biermann Ch. Handbook of Pulping and Papermaking

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294 11- ENVIRONMENTAL IMPACT

11.8 U.S. REGULATIONS

U.S.

government regulations for effluent

requirements can be fairly complex. The EPA

sets maximum guidelines for the states. The states

may impose stricter regulations and regulate

additional items, but they cannot be less stringent

than EPA regulations. It can be quite difficult to

obtain all of the information one needs to deter-

mine compliance, learn how to apply for permits,

find state regulations, etc. Fortunately there are

some resources available that collect this informa-

tion into sets of large volumes with loose-

leaf bindings that allow sections to be replaced as

they are updated. Each section is dated for the

time of its printing. Unfortunately, the annual

subscription rates for these resources is fairly

high, making them fairly hard to find in libraries,

but this resource provides important information.

The information from this section was ob-

tained from the BNA Reporter (Environmental

Reporter, Bureau of National Affairs, Inc., 1231

25th Street, Washington, D.C.). There are vol-

umes on Federal Regulations, State Water Laws,

and State Air Laws for many industries.

EPA regulations for pulp and paper effluents

fall into 26 categories by type of mill, such as

unbleached kraft and semi-chemical. BOD5, TSS,

and pH are covered by BPT (best practicable

control technology) regulations,

while

pentachloro-

phenol and trichlorophenol are covered by BAT

(best available technology economically achiev-

able).

The phenols occur from biocides that may

be used in the various processes and will not be

considered further. New mills must meet NSPS

(new source performance standards) regulations.

Generally speaking

day averages may not exceed

about twice the 30 day average. The pH levels

are reported as allowable ranges; no discharges

outside these ranges is ever allowed. Table 11-4

gives some example effluent regulations for sever-

al types of mills from the January 30, 1987 listing

of the BNA Reporter,

While the air quality standards (as of June

23,

1989) are not broken down into as many

subsections as the effluent standards, they are

slightly more complicated and detailed and have

Table 11-4. Thirty day average of EPA aUow-

able effluent discharges for several types of

mills.

Values are kg per 1000 kg air dry pulp

or pH range.

Type of mill

BPT Unbleached kraft

NSPS linerboard

BPT Semi-chemical

Dissolving kraft

BOD5

2.8

1.8

4.4

12.3

TSS

6.0

3.0

5.5

20.0

6-9

5-9

6-9

5-9

many exceptions. Units are reported in g/m^ or

grains/ft^; note that 1 g/m^ = 0.43700

grains/tf.

Performance standards for kraft pulp mills

include particulate matter and TRS. Particulate

matter must be below 0.10 g/dscm (0.044 gr/dscf)

corrected to 8% oxygen with less than

35%

opaci-

ty for the recovery boiler, below 0.1 g/kg black

liquor solids for the smelt dissolving tank, and

0.15 g/dscm for gaseous fossil fuel (0.30 g/dscm

for liquid fossil fuel) fired lime kilns corrected to

10%

oxygen.

Total reduced sulfur (TRS) for most sources

must be below 5 ppm by volume corrected to 10%

oxygen. However, if the overall TRS emissions

are below 5 g/MT (0.01 lb/ton) air dry pulp then

point sources are allowed to be higher than 5 ppm.

Cross recovery furnaces are to be below 25 ppm

by volume at 8% oxygen. The smelt dissolving

tank limit is 16 g/MT (0.033 lb/ton) black liquor

solids, the lime kiln limit is 8 ppm by volume at

10%

oxygen, and the recovery boiler limit is 5

ppm by volume at 8% oxygen. The air quality

standards section also includes information on

monitoring emissions and operations. To obtain

the corrected pollutant concentration at the correct-

ed oxygen concentration from the measured

oxygen concentration, use the following formula:

Qorrected ^ Qieasured ^ (^1 " ^/21 " •*)

where X is 8% or 10%

is the 12 hour average volimie O2

concentration

ANNOTATED BIBLIOGRAPHY 295

11.9 ANNOTATED BIBLIOGRAPHY

General

U.S. Environmental Protection Agency,

Environmental Pollution Control Pulp and

Paper

Industry,

Part /, Air, EPA-625/7-76-

001 (1976). This is a useful reference for

amounts and sources of various air pollutants

in the pulp and paper industry, especially

from kraft pulping. Control measures such

as partial liquor oxidation before direct con-

tact evaporation are described with emissions

levels given for operations with and without

such systems.

Weak

black liquor

oxidation

Galeano, S.F. and CD. Amsden, Oxidation

of weak black liquor with molecular oxygen,

TappiJ.

53(11):2142-2146(1970).

Nitrogen oxide formation

Ermenc, E.D., Controlling nitric oxide emis-

sions,

Chem. Eng.

77(12):

103-05(Jun 1,

1970).

Kraft recovery boiler operation

Van Heiningen, A.R.P., Chemical recovery

conference highlights CFD modelling and

black liquor gasification, Pulp Paper Can.

93(8):9-16(1992). The highlights of the

Seattle, Washington conference of 67 techni-

cal presentations.

Electrostatic precipitators

5. White, H.,

Industrial Electrostatic

Precipita-

tion,

Addison-Wesley, 1963. The author

describes the industrial operation and theory

of electrostatic precipitators.

Bleaching

6. Neilson, A.H., et al., The environmental fate

of chlorophenolic constituents of bleachery

effluents, Tappi J. 73(3):239-247(1990), 43

references.

Dioxin

Harris, F.E., Dioxins~an overview,

Tappi

73(4):267-269(1990). This is a nontechnical

overview about dioxins, their sources, the

history of their measurement, and why we

can never reach "zero concentration" of

dioxins.

8. Fingerhut, M.A., Cancer mortality in work-

ers exposed to 2,3,7,8-tetrachlorodibenzo-p-

dioxin, K Engl /. Med, 324:212-218(1991).

The results of a retrospective cohort study of

5172 workers at 12 plants in the U.S. that

produced chemicals contaminated with

TCDD does not confirm the high relative

risks reported for many cancers in previous

studies.

9. Bailer, in, J.C, How dangerous is dioxin?,

N. Engl J, Med, 324:260-262(1991). This

is an editorial on the toxicity of dioxin with

9 references.

10.

Luthe, C.E., P.E. Wrist, and R.M. Berry,

An evaluation of the effectiveness of dioxins

control strategies on organochlorine effluent

discharge from the Canadian bleached chem-

ical pulp industry. Pulp & Paper Can,

93(9):T239-T248(1992). This paper is an

excellent introduction to dioxins in chemical

pulp mills. It is a "must have in your li-

brary" article due to its very direct, practical

approach.

Anaerobic treatment

of mill wastewaters

11.

Lee, Jr., J.W., D.L. Peterson, and A.R.

Stickney, Anaerobic treatment of pulp and

paper mill wastewaters, Tappi Proceedings,

19S9

Environmental

Conference,

473-496.

An extensive article on this subject was given

by CH2M Hill personnel. About 37 paper

mills around the world were either using or

were installing the process as of the article's

printing.

296 11- ENVIRONMENTAL IMPACT

EXERCISES

Water pollution

What makes water look cloudy?

What are four undesirable aspects of pulp

and paper mill aqueous effluents?

Which of the following is the most difficult

to remove from the water effluent of a

bleached kraft pulp mill?

a) fibers b) BOD

c) color

A closed can of a carbonated beverage with

contents at 25 °C is much more apt to bubble

out the top than one with contents at 5°C.

Why is this so, and what does this have to do

with water pollution?

Why does the determination of BOD levels

take several days?

8. If a mill discharges dioxin at 10 parts per

quadrillion in 20 million gallons of effluent

every day, what is the mass of dioxin dis-

charged in one year?

Air pollution

9. Which of

the

following are removed by alkali

scrubbing of gases and why? HjS, CH3SH,

(CH3)2S, and CH3SSCH3? What effect does

mild oxidation of black liquor prior to con-

centration have on this problem?

10.

Where is methyl sulfide produced during

chemical pulping? Is it a desirable product?

11.

Where do nitrogen oxides originate?

Why are permissible levels of BOD emission 12. What are ambient and point sampling?

often lower during hot months of the year?

13.

Describe the tradeoffs involved in controlling

6. How is color removed from mill effluent? air pollutants from the kraft recovery boiler.

METRIC AND ENGLISH UNITS AND UNIT ANALYSIS

12.1 METRIC UNITS

12.2 ENGLISH AND METRIC UNITS

The metric system (called SI from the French

for systeme internationale) is the common system

used in the scientific literature to describe mea-

surements . All measurements can be derived from

the seven base units and two supplementary units

shown in Table 12-1. Since the U.S. pulp and

paper industry (unfortunately!) uses English mea-

surements extensively, some of the base SI units

are given in terms of their approximate English

system equivalents. Because only seven funda-

mental units are used in the metric system, it is

extremely easy to use in problem-solving. Even

when going from English to English units, it is

sometimes helpful to use metric units as interme-

diates.

The multipliers that are used as prefixes

before the units are given in Table 12-2. Here the

English equivalents of the multipliers greater than

one are given.

Complex measurements are combinations of

the base units. For example, area is derived from

length and is actually length^ such as m^; volume

is also derived from length and is length^ such as

m^; density is derived from mass and volume with

units such as kg/w? or g/cw?. Table 12-3 gives

the list of derived SI units which have special

names.

Table 12-4 gives some values of

the

universal

constants that are used in various aspects of engi-

neering and science. Table 12-5 gives some

additional metric based units with special names

that have traditional use.

In the following section, the numerous Eng-

lish

units

will be presented with conversion factors

to metric units. Also, the relationships between

many of the English units are presented.

Tables 12-6 and 12-7 are designed to define

most commonly encountered English units in pulp

and paper without having unnecessary conver-

sion factors for all of the possible derived units.

For example, if one knows the conversion factor

for cm to in. then cm^ can be converted to in.^ and

cm^ to in.^ Similarly, gal/min can easily be

converted to ml/s if one has a conversion factor

for gallons to milliliters (or liters) and knows there

are 60 seconds in a minute. The technique for this

is shown in Section 12.3. Table 12-8 gives units

for paper analysis. Table 12-9 gives DIN format

sizes of paper.

Tables in this chapter include:

12-1.

Base units of the metric system.

12-2.

Prefix units with corresponding multipli-

ers for SI units.

12-3.

Derived SI units with special symbols

and names.

12-4.

Table of universal constants.

12-5.

Other metric units with special names.

12-6.

Fundamental and derived English units

with special names and their conversion

factors.

12-7.

Common compound units with conver-

sion factors.

12-8.

Paper analysis conversion factors.

12-9.

DIN format sizes of paper.

297

298 12. METRIC AND ENGLISH UNITS AND UNIT ANALYSIS

Table 12-1 Base units of the metric system.

Base Quantity

length

mass

time

temperature

amount by number

electric current

luminous intensity

SI Unit

meter

kilogram

second

kelvin

mole

ampere

candela

Symbol

mol

Equivalent English units

39.3701 inches

2.2046

pounds (g = 1.00)

second

K=(5/9)-(°F-32) + 273.15

6.022010^^

6.2422-10^«electrons/s

Supplementary Units

plane angle

solid angle

radian

steradian

rad

360^/27r = 57.296° of a circle

360°/27r = 57.296° of

sphere

Table 12-2. Prefix units with corresponding multipliers for SI units.

Name

deca

hecto

kilo

mega

giga

tera

peta

exa

Symbol

Multiplier

100

1000

10*

10^

10'2

10'^

lO'*

English

Equivalent

thousand

million

billion^

trillion^

quadrillion

quintillion

Name

deci

centi

milli

micro

nano

pico

femto

atto

Symbol

Multiplier

O.I

0.01

0.001

io-«

10-'

10-12

io-'5

lQ-18

^British define

billion

as a

million millions

10^^

^British defme

trillion

as a

million billions

10^*

ENGLISH AND METRIC UNITS 299

Table 12-3. Derived SI units with special symbols and names.

Quantity

SI units with special symbols

frequency

force

pressure; stress

energy; work; heat

power, radiant flux

electric charge

electric potential

electric capacitance

electric resistance

electric conductance

magnetic flux

magnetic flux density

inductance

luminous flux

luminous flux density

radionuclide activity

absorbed dose of

ionizing radiation

Other derived SI units

area

volume

speed, velocity

acceleration

wavenumber

concentration

density of mass

moment of force

surface tension

specific heat capacity

Name

hertz

newton

pascal

joule

watt

coulomb

volt

farad

ohm

Siemens

weber

telsa

henry

lumen

lux

becquer

gray

square meter

cubic meter

Symbol

meter per second

meter per second squared

per meter

molarity

kilogram per cubic meter

newton meter

newton per meter

joule per kilogram kelvin

Base Units

(cycle)-s"^

mkg-s"^

m"^-kg-s'^

m^kg-s"^

m^kgs"^

A-s

m^-kg-s'^-A'^

jl^-2.j^g-l.g4.^2

m^-kg-s'^-A"^

m"^-kg'^-s^-A^

m^-kg-s'^-A'^

kg-s-^-A-^

m^-kgs"^A'^

cd-sr

m"^'cd-sr

s-i

-2

m/s

m/s^

m-'

mol/w?

kg/m'

N-m

N/m

J/(kg-K)

Other Units

N/m2

J/s

W/A

C/V

V/A

A/V

V-s

Wb/m^

Wb/A

Im/m^

J/kg

mol/L

g/L

300 12. METRIC AND ENGLISH UNITS AND UNIT ANALYSIS

Table 12-4. Table of universal constants.

Constant

Avogadro constant

Gas constant

Faraday constant

Planck constant

Speed of light (vacuum)

Acceleration, gravity

Symbol

•K

Value

6.0220-lO^^mol-'

8.314

J-moH-K'

0.08206

Latm K^ moli

62.37 LTorrK-'mol-i

96485 Cmol-'

6.6262-10-^^ Js

2.99792-10«m-s-i

9.80665

m-s-2 (by definition)

3.141592654

2.718281828

Table 12-5. Other metric units with special names (not SI).

Quantity

CGS

System

derived

units

force

energy

viscosity

kinematic viscosity

acceleration, gravity

Miscellaneous

distance (obsolete)

area

volume

mass,

metric ton

radionuclide decay

absorbed dose

exposure

Name

Symbol

Base Units

(using

base units of

cm,

g and s)

dyne

erg

poise

stokes

gal

micron

millimicron

angstrom

hectare

liter^

tonne

Curie

rad

roentgen

dyn

erg

Gal

m/x

A or A

1,L

torMT

cm-g-s'^

cm^-g-s"^

cm'^-g-s"^

cm-s"^

cms"^

jLcm

10-^^

10,000 m^

0.001 m^

10^

3.710i^Bq

0.01 Gy

2.58 X 10-^

Other Units

10-^

0.1 nm

0.01 km^

1000cm^

1000 kg

C/kg

^One liter of water weighs exactly 1 kg at 25°C; 1 ml is then 1 g.

ENGLISH

AND

METRIC UNITS

301

Table

12-6.

Fundamental

and

derived English units with special names

and

their

conversion factors

other units.

The

reciprocal

listed

for

reverse conversions.

(Less than five significant figures indicates exact

to at

least

six

significant figures.)

Unit

Abbrev.

Dimensionless

values

dozen

score

gross

thousand

Units

length

mil

caliber

inch

foot

yard

fathom

rod

chain

(Gunter's)

(Ramsden's)

furlong

mile

(statute)

(nautical)

league

doz

mil

m.,

ft,'

fath

rod

fur.

mile,

(statute

nautical)

Multiplier

144

1000

0.001

0.01

2.54

30.48

0.3048

0.91440

16.5

100

660

1.6093

5280

1.852

6076.1

Other Unit

inch

meter

foot

inch

foot

mile

Reciprocal

0.083333

0.05

0.0069444

0.001

1000

100

0.39370

0.032808

3.2808

0.083333

1.0936

0.33333

0.027778

0.16667

0.060606

0.015152

0.01

0.0015152

0.62137

0.00018939

0.53996

0.00016458

0.33333

302 12. METRIC AND ENGLISH UNITS AND UNIT ANALYSIS

Table 12-6. Fundamental and derived English units with special names and their

conversion factors. Cont'd.

Unit

Force

kip

poundals

Units

of area

acre

Units

volume

teaspoon, U.S.

tablespoon

ounce

U.S. fluid oz

pint*

quart

(U.S.

liquid)

(U.S.

dry)

(British)

gallon'

peck'

bushel'

barrel

Wood,

volumetric

board foot

cord, stacked wood

unit, usu. chips

cunit, solid wood

stere

Abbrev.

acre

tsp

Tbs

gal

bbl

fbm

Multiplier

4448.2

0.13826

0.0015625

0.40469

4.93

14.79

0.029574

0.5

0.94635

1.1012

1.1365

42 (petrol.)

0.083333

128

2400

100

Other Unit

mi^

hectare

gallon (U.S. liquid)

ft3

ft^

lb,

dry

ft^

Reciprocal

0.00022481

7.2327

640

2.4711

0.20284

0.067613

33.814

1.0567

0.98794

0.87988

0.25

0.125

0.03125

0.023810

0.0078125

0.00041667

0.01

^ The British pint, gallon, peck, and bushel are made up of 0.5, 4, 8, and 32 British

quarts, respectively, while the U.S. pint, gallon, peck, and bushel have the same number

of U.S. dry quarts. One U.S. liquid gallon of water has a weight of

8.349

lb. There

are

7.4805

gallons per ft^ and 1

ft^

of water weights 62.45 lb.

ENGLISH AND METRIC UNITS 303

Table 12-6. Fundamental and derived English units with special names and their

conversion factors. ContM.

Unit

Units

mass^

grain

carat, metric

ounce

avoirdupois

troy (for gold)

pound

avoirdupois

ton (short ton)

ton (long ton)

metric ton, tonne

Units

of pressure

atmosphere

psi (Ib/sq in)

Units

of time

minute

hour

day

week

year (solar)

Abbrev.

lb,

t, MT

atm

psi

min

hr,

Multiplier

64.799

0.2

28.350

31.103

453.59

2000

2240

2204.6

1000

1.013310^

760

14.696

33.899

29.921

1.0332

6894.8

3600

168

365.25

3.1558-10'

Other Unit

pound

pascal

mmof Hg

psi

feet water

in.

technical atm

pascal

min

hour

day

hour

day

Reciprocal

0.015432

0.035274

0.032151

0.0022046

0.0005

0.00044643

0.00045359

0.001

9.8692-10-^

0.0013157

0.068046

0.029450

0.033421

0.96787

0.0001450

0.016667

0.00027778

0.041667

0.14286

0.59524

0.0027379

3.168810-*

Most English units of "mass" such as the pound (except the slug which really is mass)

are really measures of weight at the earth's surface. The mass of an object is constant;

the weight depends on the acceleration of gravity. The English units are commonly set

equal to SI mass units, although this is not strictly correct.