PSE 322 QUIZ 1-7 QUESTIONS AND ANSWERS
What are the three major chemical components of wood (other than water)? - Answers
:Cellulose, hemicellulose, lignin
Which of the following is NOT classified as an extractive component of wood? -
Answers :Phenolpropane
Of the following items commonly present in papermaking furnish, which has the largest
(end-to-end distance)? - Answers :Fibers
What process, happening during refining, can account for increased conformability of
the fibers while they are still wet? - Answers :Internal delamination
What often becomes ribbon-like in the course of pulping, refining, and formation into
paper? - Answers :Fibers
What is the correct term used to describe the process leading to thin, hair-like strands of
cellulose extending into the water from the outside of a refined kraft pulp fiber? -
Answers :Fibrillation
Which of the following typically has the largest cell wall thickness? - Answers :Softwood
fibers (Southern US)
Which of the following is multi-cellular? - Answers :Trachied ***
libriform fiber ***
incorrect
What is typically 3 to 5 mm in size? - Answers :Length of softwood tracheids used in
papermaking
What type of fiber is most conformable? - Answers :Refined kraft fibers
Which of the following kinds of wood does not have vessels? - Answers :Softwoods
(conifers)
What is the primary purpose of a pressure screen in the approach flow to a paper
machine? - Answers :Remove larger items
What is a typical width of slots in a slotted pressure screen? - Answers :0.3 mm
What two streams are combined at the fan pulp of a typical paper machine? - Answers
:Thick stock and white water
The negative charge of typical delignified fibers can be attributed largely to the presence
of what? - Answers :Carboxylic acid
,Before bleaching, kraft-pulped fibers have what color? - Answers :Brown
Which of the following fibers is typically the thinnest (smallest diameter)? - Answers
:Eucalyptus
Which type of fibers has many broken ends, kinks in the fibers, and miscellaneous
debris? - Answers :Recycled
What are the raised portions called on a typical refiner plate? - Answers :Bars
What helps to prevent formation of a fiber mat within the pressure screen system? -
Answers :Action of the rotor
Which of the following is NOT a typical component added to the pulp mixture in a chest
located somewhere before the stuff box of a paper machine? - Answers :thin stock
Which two unit operations in the paper machine system typically involve the highest
level of hydrodynamic shear stress? - Answers :Fan pulp and pressure screen
Formation of paper occurs on what part of the paper machine? - Answers :Wire section
What two items often pass more than one time through the primary circuit of flow in a
paper machine system? - Answers :Water and some of the fines
What type of costs related to the manufacture of paper does not change when the
amount of product being made per unit time in a paper mill changes? - Answers :Fixed
Costs
What type of chemical group, and how many, is present on each anhydroglucose
repeating unit of cellulose? - Answers :Hydroxyl (-OH), 3 of them
What polymeric component of wood is comprised of various phenol-propane subunits? -
Answers :lignin
Excess white water beyond what is needed at the fan pump to dilute the thick stock
goes from the paper machine primary circuit to what unit operation? - Answers :Save-all
system
Fibers from juvenile wood (formed when the tree was very young) typically have what
attribute? - Answers :Thinner cell walls than mature wood
As a consequence of typical kraft pulping and bleaching processes, what happens to
the proportion of cellulose in a fiber? - Answers :It increases due to the breakdown and
dissolution of lignin and some hemicellulose.
, How does the shape of a typical kraft fiber change as it is being refined under ordinary
conditions? - Answers :The lumen collapses, making the fiber more ribbon-like.
What is the name of the hollow space in the middle of a hardwood fiber or in a softwood
tracheid? - Answers :Lumen
Which of the following generally cannot pass through the slots of a typical slotted
pressure screen system? - Answers :Shives
What item is moving in a hydrocyclone cleaner device? - Answers :thin stock
Which of the following is true regarding the S2 sublayer within wood fibers often used
for paper pulp? - Answers :The most important layer, by mass
Xylem is the Latin name for what? - Answers :wood
Paper made from what kind of fibers tends to be thinner and denser after typical
processing conditions? - Answers :Juvenile wood fibers
According to the illustrations by Goring (1975), where is much of the lignin located in the
cellulose fiber? - Answers :In domains within the cell wall
Accepts from which bank of hydrocyclones goes forward to the next unit operation
(pressure screen)? - Answers :primary
What's the name of a popular injection system traditionally used for chemical addition
after the pressure screen and before the headbox? - Answers :ring header
Excess pulp slurry (thick stock), beyond what is needed by the paper machine to give
the desired basis weight, overflows from the stuff box and goes where? - Answers
:Machine chest
What type of fiber is obtained from the processing of sugar cane? - Answers :Bagasse
What unit operation involves repeated shearing and compression of papermaking fibers
between a rotor and a stator? - Answers :refining
A typical branched polymer has what kind of structure? - Answers :Chains of polymer
starting in the middle of other chains
Viscosity measurement of polymer solutions can be used to estimate what kind of
average molecular mass? - Answers :Weight average
Suppose that you have a polyelectrolyte that contains quaternary ammonium groups
and no other ionizable groups. What will happen to the charge of the polymer if the pH
is raised from 4.5 (acidic papermaking) to 8 (alkaline papermaking)? - Answers :Nothing
What are the three major chemical components of wood (other than water)? - Answers
:Cellulose, hemicellulose, lignin
Which of the following is NOT classified as an extractive component of wood? -
Answers :Phenolpropane
Of the following items commonly present in papermaking furnish, which has the largest
(end-to-end distance)? - Answers :Fibers
What process, happening during refining, can account for increased conformability of
the fibers while they are still wet? - Answers :Internal delamination
What often becomes ribbon-like in the course of pulping, refining, and formation into
paper? - Answers :Fibers
What is the correct term used to describe the process leading to thin, hair-like strands of
cellulose extending into the water from the outside of a refined kraft pulp fiber? -
Answers :Fibrillation
Which of the following typically has the largest cell wall thickness? - Answers :Softwood
fibers (Southern US)
Which of the following is multi-cellular? - Answers :Trachied ***
libriform fiber ***
incorrect
What is typically 3 to 5 mm in size? - Answers :Length of softwood tracheids used in
papermaking
What type of fiber is most conformable? - Answers :Refined kraft fibers
Which of the following kinds of wood does not have vessels? - Answers :Softwoods
(conifers)
What is the primary purpose of a pressure screen in the approach flow to a paper
machine? - Answers :Remove larger items
What is a typical width of slots in a slotted pressure screen? - Answers :0.3 mm
What two streams are combined at the fan pulp of a typical paper machine? - Answers
:Thick stock and white water
The negative charge of typical delignified fibers can be attributed largely to the presence
of what? - Answers :Carboxylic acid
,Before bleaching, kraft-pulped fibers have what color? - Answers :Brown
Which of the following fibers is typically the thinnest (smallest diameter)? - Answers
:Eucalyptus
Which type of fibers has many broken ends, kinks in the fibers, and miscellaneous
debris? - Answers :Recycled
What are the raised portions called on a typical refiner plate? - Answers :Bars
What helps to prevent formation of a fiber mat within the pressure screen system? -
Answers :Action of the rotor
Which of the following is NOT a typical component added to the pulp mixture in a chest
located somewhere before the stuff box of a paper machine? - Answers :thin stock
Which two unit operations in the paper machine system typically involve the highest
level of hydrodynamic shear stress? - Answers :Fan pulp and pressure screen
Formation of paper occurs on what part of the paper machine? - Answers :Wire section
What two items often pass more than one time through the primary circuit of flow in a
paper machine system? - Answers :Water and some of the fines
What type of costs related to the manufacture of paper does not change when the
amount of product being made per unit time in a paper mill changes? - Answers :Fixed
Costs
What type of chemical group, and how many, is present on each anhydroglucose
repeating unit of cellulose? - Answers :Hydroxyl (-OH), 3 of them
What polymeric component of wood is comprised of various phenol-propane subunits? -
Answers :lignin
Excess white water beyond what is needed at the fan pump to dilute the thick stock
goes from the paper machine primary circuit to what unit operation? - Answers :Save-all
system
Fibers from juvenile wood (formed when the tree was very young) typically have what
attribute? - Answers :Thinner cell walls than mature wood
As a consequence of typical kraft pulping and bleaching processes, what happens to
the proportion of cellulose in a fiber? - Answers :It increases due to the breakdown and
dissolution of lignin and some hemicellulose.
, How does the shape of a typical kraft fiber change as it is being refined under ordinary
conditions? - Answers :The lumen collapses, making the fiber more ribbon-like.
What is the name of the hollow space in the middle of a hardwood fiber or in a softwood
tracheid? - Answers :Lumen
Which of the following generally cannot pass through the slots of a typical slotted
pressure screen system? - Answers :Shives
What item is moving in a hydrocyclone cleaner device? - Answers :thin stock
Which of the following is true regarding the S2 sublayer within wood fibers often used
for paper pulp? - Answers :The most important layer, by mass
Xylem is the Latin name for what? - Answers :wood
Paper made from what kind of fibers tends to be thinner and denser after typical
processing conditions? - Answers :Juvenile wood fibers
According to the illustrations by Goring (1975), where is much of the lignin located in the
cellulose fiber? - Answers :In domains within the cell wall
Accepts from which bank of hydrocyclones goes forward to the next unit operation
(pressure screen)? - Answers :primary
What's the name of a popular injection system traditionally used for chemical addition
after the pressure screen and before the headbox? - Answers :ring header
Excess pulp slurry (thick stock), beyond what is needed by the paper machine to give
the desired basis weight, overflows from the stuff box and goes where? - Answers
:Machine chest
What type of fiber is obtained from the processing of sugar cane? - Answers :Bagasse
What unit operation involves repeated shearing and compression of papermaking fibers
between a rotor and a stator? - Answers :refining
A typical branched polymer has what kind of structure? - Answers :Chains of polymer
starting in the middle of other chains
Viscosity measurement of polymer solutions can be used to estimate what kind of
average molecular mass? - Answers :Weight average
Suppose that you have a polyelectrolyte that contains quaternary ammonium groups
and no other ionizable groups. What will happen to the charge of the polymer if the pH
is raised from 4.5 (acidic papermaking) to 8 (alkaline papermaking)? - Answers :Nothing
