Forest Sciences Commons^™

Selective Recovery Of Corrugated Clippings, Timothy J. Rourke

Paper Engineering Senior Theses

Selective recovery of waste corrugated into the kraft and NSSC fractions is gaining in popularity. This selective reuse of fibers enables the papermaker to use more recycled fiber in the linerboard portion of corrugated boxes. It is well documented that 100% recycled paper can be used in the medium while the highest percentage of secondary fibers in the linerboard is 30%. Greater than 30% recycled fiber in the linerboard results in poor runnability. Since reuse of secondary fibers in the medium is already at a maximum, this paper will place more emphasis on the reuse in the linerboard.

The Use Of Electrocoagulation As A Flocculating Aide For Deinking, James L. Schram

Paper Engineering Senior Theses

The effects of electrocoagulation as a flocculating aide for deinking was evaluated using a "homemade" electrode unit. The unit was inserted into a laboratory-size Voith-Morden forced-air flotation cell. The process of electrocoagulation involves two steps:

1. Reducing the zeta potential of the system to 0.0 mV by pH adjustment.

2. The passing of current through the stock suspension which causes the electrolysis of the water, and thus hydrogen and oxygen gas bubbles are produced. These gas bubbles collect ink particles to form solid-gas composites which can be removed more easily using flotation.

The process was evaluated on the forced-air flotation …

A Study Of The Effects Of Nip Width On Plybond Separation Of Board During Gravure Printing, Anne L. Liebeknecht

Paper Engineering Senior Theses

W. Hildenbrand, W. Brecht and H.-J. Knittweis did work in Germany in the late 1960's concerning the relationship between roll hardness, pressure and plybond degradation of paper board in a gravure printing process. They showed that softer rubber covered rolls caused a decrease in plybond strength. Increased pressure at the nip also caused a similar decrease. This study attempted to quantify these decreases, but was unable to produce acceptable data. Poor samples and inconsistencies in the BRDA plybond test machine are the probable causes of the high variation in the data.

The Effects Of Freeze-Drying On The Strength Characteristics Of Naturally Aged Book Papers, Steven D. Sarokin

Paper Engineering Senior Theses

Libraries occasionally have water main breaks, fires and floods. These disasters cause considerable water damage to thousands of books. Books that are left wet on the shelves will grow mold. Books that are quickly frozen and eventually freeze-dried can be restored to the shelf in good condition. Several libraries have used freeze-drying for this purpose and have had great success.

Freeze-drying is a process used to remove frozen liquid from a substance. The moist material is frozen and put in a vacuum. A high vacuum with some heat introduced will cause the frozen liquid to sublime. A dry-porous structure is …

The Influence Of Fines On An Alkyl Ketene Dimer Synthetic Sizing Agent, Andrea S. Coyle

Paper Engineering Senior Theses

It is the purpose of this thesis to attempt to evaluate the influence of fines on a alkyl ketene dimer (AKD) synthetic sizing agent and to study the role of fines on sizing.

It was found that the addition of fines lowered the degree of sizing in the sheet. Since there was more surface area available when fines were increased, more sizing agent was necessary in order to obtain the same level of sizing with a Hercules or Cobb Size Test. Since the amount of sizing agent was held constant, sizing decreased as a result of the addition of fines. …

Coagulation And Flocculation Of Flexographic Ink Washwaters By Various Organic And Inorganic Polymers, Jack R. Bray

Paper Engineering Senior Theses

A review of flocculation is presented. Included is a discussion concerning the factors controlling pigment and heavy metal removal via flocculation treatment. Also included is a brief background on the regulatory status concerning the heavy metals contained in flexographic inks. A detailed experimental procedure involving the use of jar tests and several industrial polymers is included along with the analyses performed.

It is found that flocculation treatment of flexographic washwaters produces excellent results with respect to clarity and heavy metals removal. In most cases flocculation at an optimum concentration followed by simple gravitational settling resulted in heavy metals removal well …

The Effect Of Hlb Factor On Surfactants Used In Flotation Deinking, Thomas H. Berger

Paper Engineering Senior Theses

The objective of this study is to determine the role of surfactants in flotation deinking through the use of their HLB factors. As an aside a comparison of surfactant and a product called Serfax NP-10 was made along with a study looking at the effect of surfactants and Serfax on a closed water system. It was found that an HLB of 13.5 worked best for flotation deinking and this points to the conclusion that the surfactant is working as a detergent. The Serfax product seemed to work as well as the best surfactant without any detrimental results in the closed …

The Effect Of Oxygen Treatment Of Thermomechanical Pulp On Strength And Hydrosulfite Bleachability, Robert L. Deamico

Paper Engineering Senior Theses

The literature review for this thesis was done on the expectation of acquiring an ozone generator for experimental work. This expectation was never realized. Consequently, a low consistency oxygen treatment under mild alkaline conditions and room temperature was done instead. The two major considerations were to determine the effect of this treatment on strength properties and development, and on hydrosulfite bleachability. It was found that the brightness of the pulp was reduced on alkaline oxygen treatment, but pretreatment increased the bursting strength development caused by hydrosulfite bleaching, at the same freeness level. A substantial reduction in freeness level was experienced …

The Role Of Cationic Polymers In Water Removal On A Paper Machine, Paul T. Miller

Paper Engineering Senior Theses

Cationic polymers have often been termed as both retention and/or drainage aids. A distinction was made between these two terms. Essentially drainage aids should be viewed as dewatering aids and retention aids should be viewed as those polymers that give superior retention. These effects may be interrelated, therefore the dominant characteristic should be used to classify these polymers. There have been many claimed benefits associated with the use of these cationic polymers in stock furnishes. The author felt that claimed dewatering benefits were mostly a matter of conjecture and contradictions existed. Therefore a pilot. paper machine study was designed to …

The Effect Of High Frequency Sinusoidal Strains On The Strength Properties Of Paper, Robert Mcqueary

Paper Engineering Senior Theses

The objective of this study was to determine the effect of various high frequency sinusoidal strains on the strength properties of a paper cone in a loud speaker. The stresses developed during sound propagation were approximated by applying viscoelastic theories to the paper cone's mode of response. This analysis indicated the stresses developed would be indirectly proportional to the square of the frequency in Hertz. Also relevent is the Boltzmann superposition principle which states that if a second strain is applied before the first strain is dissipated, the resultant strains are additive.

Sets of speakers were operated continuously for 120 …

Improving The Performance Of The Finckh Screen, Michael J. Ryan Iv

Paper Engineering Senior Theses

As dewatering of the stock occurs around the screen basket of a Finckh pressurized, inward flow pulp screen, from 0 to 360 degrees, stock mass flow through the outer screen annulus decreases. Some sections of the screen basket hence handle more stock than other sections.

Stock velocity is dependent on mass flow through an area. Stock velocity is critical to fiber orientation, which is in turn critical to screening.

A volute, much like a tapered manifold header, would decrease the area available for stock flow. This will maintain stock velocity around the full circumference of the screen basket.

A volute …

Increasing The Operating Consistency Of The Finckh Pressurized Screen, Jose Serrano

Paper Engineering Senior Theses

The purpose of this study was to increase the operating consistency of The FINCKH pressurized screen. The main objective was to obtain good, efficient pulp cleaning at consistencies greater than 0.8%, and to observe the fractionating ability of the screen.

Cleaning efficiencies based on the removal of shives present in Groundwood were obtained in the order of 45%. Control runs were made at 0.7% consistency.

Installation of a linoleum volute - shaped element on the feed side of the screening zone, increased the velocity of the stock at low consistency (0.7%) without affecting the cleaning efficiency. At high consistency (1.26%) …

The Effects Of Cationic Valence On Wash Deinking Of Newsprint, Lawrence E. Mcenroe

Paper Engineering Senior Theses

The effects of cationic valence were tested against final pulp brightness in the wash deinking process on newsprint. The electrolytes used were AlCl₃,CaCl₂ and NaCl. The concentrations were varied from 8.32 x 10^-4 M to 100 times that amount on all three electrolytes. The effects were studied on the wash water and the cooking liquor seperately, using deionized water as a control run. It was found that there was a noticeable loss of brightness even at the lowest level of electrolyte addition in both the wash water trials and the cooking liquor trials. The effect was …

Flotation As A Method Of Separating Shot Particles From Mineral Wool Fibers, Thomas C. Harrison

Paper Engineering Senior Theses

The object of this thesis is to determine whether flotation will succeed as a method of separating shot from mineral wool fibers. The methods of manufacturing mineral wool are explored in detail. Also the three types of mineral wool (dark wool, white wool and ceramic fiber) are examined for properties. Various current and possible methods of separation are explored and discussed. The fibers were floated in a Voith flotation cell, and the floated fibers, as well as some of the virgin fibers, were classified in a Clark classifier. This was done in order to attempt to determine the effect of …

Use Of Heat Pumps In Vapor Absorption Systems, Charles A. Bartocci

Paper Engineering Senior Theses

The object of this study is to compare the performance of a gas fired dryer and a dryer that utilizes a heat pump for it's source of heat. Since a heat pump was unavailable for testing, ideal models were used to simulate heat pump behavior. Two temperatures and three different humidities were tested. To simulate the different humidity conditions the solvent coater-dryer was used with a water spray device in one of the heating zones. Using a psychometric chart and wet bulb dry bulb measurements the relative humidity was determined. From the data two curves were generated. Using those curves, …