Fast Flash Mixing of Retention Aids and Starch with Filler before Paper Machine Cuts Production Costs and Reduces Environmental Load

Paper fillers materials are less expensive than fiber, allowing reduced production costs and improvement of paper properties. A small pilot scale in-situ laboratory calcium carbonate filler precipitation unit was developed and designed with the objective to provide enough pulp fiber containing in-situ precipitated calcium carbonate for a small 12-inch (304 mm) wide laboratory paper machine. The in-situ precipitation system requires the reactants calcium hydroxide and carbon dioxide and was tested with a eucalyptus pulp fiber pulp suspension. The final precipitated in-situ filler content achieved was 38.2%, 55.5% and 66.6% based on initial eucalyptus pulp fiber content. The precipitation time from an initial pH of 12.77, 12.76 and 11.98 to an final pH of 7.29, 7.55, and 7.28 for the 3 kg, 6kg, and 9 kg of calcium hydroxide reactant addition was 45 minutes for the 3 kg and 9 kg calcium hydroxide addition and 40 min. for the 6 kg calcium hydroxide addition.

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Universal tooling cuts jig and fixture production costs

Production Engineer ◽

10.1049/tpe.1982.0220 ◽

1982 ◽

Vol 61 (12) ◽

pp. 27

Keyword(s):

Production Costs

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Establishment and Production Costs for Peach Orchards in Florida: Enterprise Budget and Profitability Analysis

EDIS ◽

10.32473/edis-fe1016-2017 ◽

2017 ◽

Vol 2017 (4) ◽

Author(s):

Ariel Singerman ◽

Marina Burani Arouca ◽

Mercy A. Olmstead

Keyword(s):

Discount Rate ◽

Production Costs ◽

Fixed Costs ◽

Average Price ◽

Land Preparation ◽

Profitability Analysis ◽

Enterprise Budget ◽

Marketable Fruit ◽

Peach Orchard

The article summarizes the establishment and production costs, as well as the potential profitability of a peach orchard in Florida. Our findings show the initial investment required for a peach operation in Florida to be $6,457 per acre; the expense in land preparation and planting alone in year 1 is $2,541 per acre. Variable and fixed costs in years 2 through 15 average $5,680 per acre. As an example of profitability, when using a 10% discount rate, an operation yielding 6,525 (7,254) pounds of marketable fruit per acre during its most productive years obtains a positive NPV when the average price is $2.38 ($2.13) per pound.

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Environmental benefits of magnesium hydroxide-based peroxide bleaching of mechanical pulp – mill results

TAPPI Journal ◽

10.32964/tj12.6.9 ◽

2013 ◽

Vol 12 (6) ◽

pp. 9-15 ◽

Cited By ~ 1

Author(s):

TOMI HIETANEN ◽

JUHA TAMPER ◽

KAJ BACKFOLK

Keyword(s):

Sodium Hydroxide ◽

Magnesium Hydroxide ◽

Oxygen Demand ◽

Pulp Mill ◽

Transition Metal Ions ◽

Environmental Benefits ◽

Raw Material ◽

Paper Machine ◽

High Brightness ◽

Peroxide Bleaching

The use of a new, technical, high-purity magnesium hydroxide-based peroxide bleaching additive was evaluated in full mill-scale trial runs on two target brightness levels. Trial runs were conducted at a Finnish paper mill using Norwegian spruce (Picea abies) as the raw material in a conventional pressurized groundwood process, which includes a high-consistency peroxide bleaching stage. On high brightness grades, the use of sodium-based additives cause high environmental load from the peroxide bleaching stage. One proposed solution to this is to replace all or part of the sodium hydroxide with a weaker alkali, such as magnesium hydroxide. The replacement of traditional bleaching additives was carried out stepwise, ranging from 0% to 100%. Sodium silicate was dosed in proportion to sodium hydroxide, but with a minimum dose of 0.5% by weight on dry pulp. The environmental effluent load from bleaching of both low and high brightness pulps was significantly reduced. We observed a 35% to 48% reduction in total organic carbon (TOC), 37% to 40% reduction in chemical oxygen demand (COD), and 34% to 60% reduction in biological oxygen demand (BOD7) in the bleaching effluent. At the same time, the target brightness was attained with all replacement ratios. No interference from transition metal ions in the process was observed. The paper quality and paper machine runnability remained good during the trial. These benefits, in addition to the possibility of increasing production capacity, encourage the implementation of the magnesium hydroxide-based bleaching concept.

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Microstructure simulation of early paper forming using immersed boundary methods

TAPPI Journal ◽

10.32964/10.32964/tj10.11.23 ◽

2011 ◽

Vol 11 (11) ◽

pp. 23-30 ◽

Cited By ~ 5

Author(s):

ANDREAS MARK ◽

ERIK SVENNING ◽

ROBERT RUNDQVIST ◽

FREDRIK EDELVIK ◽

ERIK GLATT ◽

...

Keyword(s):

Early Paper ◽

Contact Model ◽

Fiber Suspension ◽

Beam Equation ◽

Immersed Boundary ◽

Paper Machine ◽

Immersed Boundary Methods ◽

Element Discretization ◽

Microstructure Simulation ◽

Boundary Methods

Paper forming is the first step in the paper machine where a fiber suspension leaves the headbox and flows through a forming fabric. Complex physical phenomena occur as the paper forms, during which fibers, fillers, fines, and chemicals added to the suspension interact. Understanding this process is important for the development of improved paper products because the configuration of the fibers during this step greatly influences the final paper quality. Because the effective paper properties depend on the microstructure of the fiber web, a continuum model is inadequate to explain the process and the properties of each fiber need to be accounted for in simulations. This study describes a new framework for microstructure simulation of early paper forming. The simulation framework includes a Navier-Stokes solver and immersed boundary methods to resolve the flow around the fibers. The fibers were modeled with a finite element discretization of the Euler-Bernoulli beam equation in a co-rotational formulation. The contact model is based on a penalty method and includes friction and elastic and inelastic collisions. We validated the fiber model and the contact model against demanding test cases from the literature, with excellent results. The fluid-structure interaction in the model was examined by simulating an elastic beam oscillating in a cross flow. We also simulated early paper formation to demonstrate the potential of the proposed framework.

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Optical analysis of ink and other contaminants in process waters

TAPPI Journal ◽

10.32964/tj11.8.51 ◽

2012 ◽

Vol 11 (8) ◽

pp. 51-58

Author(s):

ANTTI HAAPALA ◽

MIKA KÖRKKÖ ◽

ELISA KOIVURANTA ◽

JOUKO NIINIMÄKI

Keyword(s):

Optically Active ◽

Process Water ◽

Paper Machine ◽

Optical Analysis ◽

Direct Process ◽

Active Components ◽

Water Contaminants ◽

Dependent Measurement ◽

Measurement Methodology

Analysis methods developed specifically to determine the presence of ink and other optically active components in paper machine white waters or other process effluents are not available. It is generally more interest¬ing to quantify the effect of circulation water contaminants on end products. This study compares optical techniques to quantify the dirt in process water by two methods for test media preparation and measurement: direct process water filtration on a membrane foil and low-grammage sheet formation. The results show that ink content values obtained from various analyses cannot be directly compared because of fundamental issues involving test media preparation and the varied methodologies used to formulate the results, which may be based on different sets of assumptions. The use of brightness, luminosity, and reflectance and the role of scattering measurements as a part of ink content analysis are discussed, along with fine materials retention and measurement media selection. The study concludes with practical tips for case-dependent measurement methodology selection.

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Impact of fiber structure on edge-wicking of highly-sized paperboard

TAPPI Journal ◽

10.32964/tj17.08.437 ◽

2018 ◽

Vol 17 (08) ◽

pp. 437-443

Author(s):

Lebo Xu ◽

Jeremy Meyers ◽

Peter Hart

Keyword(s):

Fiber Surface ◽

Manufacturing Processes ◽

Paper Machine ◽

Liquid Penetration ◽

Fiber Structure ◽

Cut Edge ◽

Local Fiber

Coffee edge-wicking testing was conducted on two groups of highly-sized paperboard manufactured at two mills with similar manufacturing processes, but with vastly different local fiber sources. Although the Hercules size test (HST) indicated similar internal size levels between the two types of board, the edge-wicking behavior was noticeably different. Analysis of fiber structure revealed that the board with more edge-wicking had fibers with thicker fiber walls, which kept the fiber lumen more open after pressing and drying on a paper machine. It was demonstrated that liquid penetration through voids between fibers in highly-sized paperboard was limited, because the fiber surface was well protected by the presence of sufficient sizing agent. Nevertheless, freshly exposed fiber walls and lumens at the cut edge of the sheet were not protected by sizing material, which facilitated edge-wicking. The correlation between fiber structure and edge-wicking behavior was highlighted in this work to inspire development of novel sizing strategies that protect the freshly cut edge of the sheet from edge-wicking.

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How to use alum with cationic dispersed rosin size

TAPPI Journal ◽

10.32964/tj15.5.331 ◽

2016 ◽

Vol 15 (5) ◽

pp. 331-335 ◽

Cited By ~ 3

Author(s):

LEBO XU ◽

JEREMY MYERS ◽

PETER HART

Keyword(s):

Zeta Potential ◽

Colloidal Particles ◽

Streaming Potential ◽

Excessive Amount ◽

Paper Machine ◽

Optimum Amount ◽

Potential Measurement ◽

Streaming Current ◽

Wide Range ◽

Laboratory Results

Retention of cationic dispersed rosin size was studied via turbidity measurements on stock filtrate with different alum and dispersed rosin size dosages. Stock charge characteristics were analyzed using both an analysis of charge demand determined via a streaming current detector and an evaluation of zeta potential of the fibers by streaming potential measurement. The results indicated that an optimum amount of alum existed such that good sizing retention was maintained throughout a wide range of dispersed rosin size dosages. However, when an excessive amount of alum was used and fines and colloidal particles were transitioned from anionic to cationic, the cationic size retention was reduced. Laboratory results were confirmed with a paper machine trial. All data suggested that a stock charge study was necessary to identify optimal alum dosage for a cationic dispersed rosin sizing program.

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Peeping at nature with the Reverend Charles A. Hall FRMS (1872–1965)

Archives of Natural History ◽

10.3366/anh.2015.0275 ◽

2015 ◽

Vol 42 (1) ◽

pp. 10-22 ◽

Cited By ~ 3

Author(s):

P. G. Moore

Keyword(s):

Nineteenth Century ◽

Natural History ◽

Production Costs ◽

Visual Appeal ◽

Young Readers ◽

Simple Language ◽

Quality Production

Attention is drawn to the contents, pedagogic style and visual appeal of the 17-volume “Peeps at nature” series published by A. & C. Black between 1911 and 1935. Edited by the Reverend Charles Albert Hall (a Swedenborgian minister), who also contributed most of the titles, this series was a quality production but one that was cheap enough to be readily accessible to young readers. Its volumes were written in simple language and included colour pictures. With time, the flamboyant artistry of the covers that so characterized the earlier volumes was replaced by more muted designs, possibly to reduce production costs. Later contributors abandoned anthropomorphism and the moralizing tone of many nineteenth-century popularizers of natural history, although styles of writing varied between the early and later contributors to the series, becoming less technical with time.

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CONVEYOR MODEL AND IMPLEMENTATION OF THE REAL NUMBERS ADDER ON FPGA

ELECTRICAL AND COMPUTER SYSTEMS ◽

10.15276/eltecs.33.109.2020.3 ◽

2020 ◽

Vol 33 (109) ◽

pp. 21-31

Author(s):

І. Ya. Zeleneva ◽

Т. V. Golub ◽

T. S. Diachuk ◽

А. Ye. Didenko

Keyword(s):

Performance Improvement ◽

Experimental Studies ◽

Production Costs ◽

Floating Point ◽

Computing Device ◽

Quartus Ii ◽

Functional Blocks ◽

Mental Testing ◽

Processor Cores ◽

Floating Point Numbers

The purpose of these studies is to develop an effective structure and internal functional blocks of a digital computing device – an adder, that performs addition and subtraction operations on floating- point numbers presented in IEEE Std 754TM-2008 format. To improve the characteristics of the adder, the circuit uses conveying, that is, division into levels, each of which performs a specific action on numbers. This allows you to perform addition / subtraction operations on several numbers at the same time, which increas- es the performance of calculations, and also makes the adder suitable for use in modern synchronous cir- cuits. Each block of the conveyor structure of the adder on FPGA is synthesized as a separate project of a digital functional unit, and thus, the overall task is divided into separate subtasks, which facilitates experi- mental testing and phased debugging of the entire device. Experimental studies were performed using EDA Quartus II. The developed circuit was modeled on FPGAs of the Stratix III and Cyclone III family. An ana- logue of the developed circuit was a functionally similar device from Altera. A comparative analysis is made and reasoned conclusions are drawn that the performance improvement is achieved due to the conveyor structure of the adder. Implementation of arithmetic over the floating-point numbers on programmable logic integrated cir- cuits, in particular on FPGA, has such advantages as flexibility of use and low production costs, and also provides the opportunity to solve problems for which there are no ready-made solutions in the form of stand- ard devices presented on the market. The developed adder has a wide scope, since most modern computing devices need to process floating-point numbers. The proposed conveyor model of the adder is quite simple to implement on the FPGA and can be an alternative to using built-in multipliers and processor cores in cases where the complex functionality of these devices is redundant for a specific task.

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