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Pulp properties are key factors to assessing the performance of a refining process, evaluating operational conditions, and optimizing the process of stock preparation. This paper presents a data-driven approach to estimate the beating degree and wet weight of pulp after refining using case-based reasoning (CBR). Historical data generated in a refining process at a paper mill was used to evaluate the proposed model. The root mean square error (RMSE) and coefficient of variance of the root mean square error (CVRMSE) of the beating degree estimation results in CBR were 1.30 and 4.32%, respectively, and the RMSE and CV-RMSE of the wet weight were 0.50 and 19.09%, respectively. The results of beating degree prediction were satisfactory, and the results of wet weight were also acceptable. To test the performance of CBR model, support vector machine algorithm (SVM) were employed to verify the effectiveness and accuracy. The RMSE and CV-RMSE of the beating degree estimation results in SVM were 1.20 and 4.02%, respectively, and the RMSE and CV-RMSE of the wet weight were 0.44 and 16.73%, respectively. As a result, the proposed model was as accurate as the SVM method. [ABSTRACT FROM AUTHOR]

A short overview of the most prospective applications of industrial lignosulfonates in various industries, such as newsprint paper production, is presented. Lignosulfonates can be utilized in technological processes in various forms, including (1) forms immobilized by paper components and (2) chemically modified forms used as functional additives to the composition of paper-making stock. [ABSTRACT FROM AUTHOR]

The increasing demand for paper has raised the need for low-cost raw materials and also for the development of new process in order to boost production. Non-wood fibers, for example agricultural residues and annual plants, are considered an effective alternative source of cellulose for producing pulp and paper sheets with acceptable properties. This paper reviews some physical and chemical properties of non-wood pulps which have effects on the making of paper. The less polluting pulping processes that use organic solvents are of interest for pulp production. The delignification of the Organosolv pulping process depends on the type of Organosolv methods and cellulosic sources used. The chemicals and cooking conditions, such as the catalysts, solvent concentration, cooking temperature, cooking time, and liquor to raw material ratio, all influence the properties of the pulp and paper. [ABSTRACT FROM AUTHOR]

The article presents research concerning the nature of web seams, their characteristics, bibliographic significance, and application to the analysis of books printed with machine-made paper made during the early nineteenth century. The collection of observations are meant to contribute further to comments presented in a paper by Catherine M. Rodriguez titled "The Use of Web Seam Evidence to Determine Format." The basic terms used in the making of paper by machine, such as wire, seam and web, are defined. Suggested systems for recording the incidence of seam marks and the possible application of seam marks to bibliographical analysis are discussed.

The article discusses an integrated approach for full stickies characterization throughout the papermaking process. It has been observed that stickies removal is needed during stock preparation of recycled pulp, however, removal efficiency along the process is not easy to assess because different types of stickies should be quantified in a newsprint mill stickies audit. In addition, macro-stickies enable one to monitor the removal efficiency while micro-stickies and secondary stickies predict the deposition potential of the pulp.

The article presents a study which aims to evaluate the efficiency of a starch-fatty complex modified filler as an alternative method for papermaking. These starch-filler composites are known to improve the filler-fiber bonding in paper including its physical property, filler retention and the sizing effect. Results show that the starch-fatty acid complexes have low solubility, making it easy to be coated on clay surface to modify clay-fiber bonding ability. Researchers also noted that paper strength could increase up to more than 100 to 200 percent by using this method. Furthermore, it has been found that the presence of fatty acids in the complex increases the water-repellant property of the handsheet which can be used to facilitate sizing during papermaking.

The article provides information on a study conducted to determine the applicability of natural colorant extracts from norbixin, curcumin and copper chlorophyll in papermaking. Upon evaluation of the saturation of the color, higher consistencies in stock preparation and higher levels of refining were found to favor the retention of these natural colorants. The color saturation of norbixin and curcumin was higher in the acidic range of pH compared with the alkaline range. Copper chlorophyllin demonstrated a higher color saturation at pH 6.0, falling below pH 5.0 and above pH 7.0. It was found that natural colorants interact well with the others additives and can be ecologically advantageous for dyeing paper products.

Features Germany-based Papierfabrik Palm GmbH & Co. KG's corrugating medium and testliner paper machine PM6. Operating experience; Pulp quality results from the stock preparation system; Details from each section of the stock preparation system; Wire width; Design speed; Pulping process; Annual production capacity.

Abstract Waste paper could potentially be used as raw material for fiber- or particle-based composites without resorting, deinking and decontamination required for paper manufacturing. The objective of this study was the evaluation of one-layer boards made of various ratios (0:100,15:85, 25:75, 50:50, 75:25 and 100:0) of waste paper flakes to wood particles mixtures (wt:wt). Three types of waste paper (newspaper, office paper and magazine paper) in pure form or mixed all together were used for board manufacture. PMDI resin at three different levels of 5, 8 and 10% without or with the addition of various amounts of wax (0.7, 1.0, 1.5 and 2.0%) were applied. The participation of waste paper flakes in boards made their appearance more attractive than ordinary particleboards and fiberboards made of wood. In contrast to internal bond, screw-holding strength and thickness swelling, properties that deteriorated substantially as the waste paper percentage increased, the bending strength was only slightly affected. By increasing the resin content all properties of boards and particularly internal bond and thickness swelling were improved. The addition of wax reduced considerably the thickness swelling of boards containing waste paper; however, even at a 2.0% level, it remained greater than the maximum permitted value specified by the relevant standard. Among the three types of waste paper tested, newspaper proved to be the most appropriate for board manufacture, and magazine paper the least appropriate. With the exception of screw-holding strength, the substitution of wood particles by mixed waste paper flakes in amounts up to 50% resulted in acceptable mechanical properties for specific applications in interior uses. [ABSTRACT FROM AUTHOR]

Abstract: The total effluent load of a paper mill can be significantly decreased by recycling of purified clear filtrate (CF) back to paper-making process. The CF treated with membranes can be reused, for instance, as wire section shower water and in the dilution of chemicals. The main requirements for a membrane in CF treatment are high filtration capacity, high retention of turbidity and low fouling tendency. Previous studies have shown that the regenerated cellulose (RC) ultrafiltration (UF) membrane C30F (current trade name UC030T) is especially suitable for the treatment of paper mill process waters. Every paper-making process is, however, different. Thus, filtration experiments are required in order to find the most optimal membrane for the treatment of a certain process water. In this study the best membrane for the treatment of acidic clear filtrate (ACF) was searched. The performance of the C30F membrane was compared with five UF and three microfiltration (MF) membranes. The results revealed that in addition to the C30F membrane, also some other membranes produced high filtration capacity with ACF (approximately 200L/(m2h bar)). All the tested membranes also retained over 90% of turbidity. The extremely hydrophilic C30F membrane had, however, lower fouling tendency compared to the other tested membranes. Therefore, it was concluded that the C30F membranes were the best possible membrane for the ACF treatment. [Copyright &y& Elsevier]

The article discusses the greener copy of the journal "Science," which has switched to recycled paper for its pages. It was said that the new paper stock is made from 30% post-consumer materials. James Landry, Science's production director, said that the journal is a bit slimmer, wherein the most significant change that readers might notice that the paper doesn't have a coating. Monica M. Bradford, Science Executive Editor, explains that the move is an indication that the Brown Printing Company is practicing what it preaches. In this regard, Brown was awarded the Forest Stewardship Council (FSC) chain-of-custody certification.

Reports that the Heidenheim, Germany-based Voith Paper has received a contract from millboard maker Kartonagen Schwarzenberg GmbH for the modernization of its stock preparation processes. Production of millboard from recovered paper.

Reports on the study for the supply of a new complete tissue line for Hayat Kimya Sanayii A.S. by PMT Italia in Rome, Italy. Production capacity of 240 metric tons per day using virgin fibers of pure pulp; Assessment of detail engineering, stock preparation lines, the tissue machine and a winder.

Explores the importance of high velocity ratio in producing a uniform mixture in concentric thick stock dilution before the fan pump. Effects of proper concentric mixing on spatial and temporal efficiency; Velocity ratio during concentric mixing experiments; Observation on stock consistency during fiber stock mixing.