Wastepaper

In the paper industry ether carboxylates are used in formulations of ink removers for wastepaper recycling [209] and quaternary softener formulations [210]. 

Pulp mills. These separate the fibers of wood or other materials, such as rags, Enters, waste-paper, and straw, in order to create pulp. Mills may use chemical, semichemical, or mechanical processes, and may create coproducts such as turpentine and tall oil. Most pulp mills bleach the pulp they produce, and, when wastepaper is converted into secondary fiber, it is deinked. The output of some pulp mills is not used to make paper, but to produce cellulose acetate or to be dissolved and regenerated in the form of viscose fibers or cellophane. 

McKinney, R. W. J., Wastepaper Preparation and Contamination Removal, Technol. of Paper Recycling, (R. W. J. McKinney, ed.), p. 48, Blackie Academic Professional, London (1995)... 

Polymers are all around us. They serve as the very basis of both plant and animal life as proteins, nucleic acids, and polysaccharides. In construction they serve as the concrete, insulation, and wooden and composite beams. At home they are found as the materials for our rugs, pillows, curtains, coatings, wastepaper baskets, water pipes, window glass, and ice cube trays. In transportation they are present in ever-increasing amounts in our aircraft, automobiles, ships, and trucks. In communication they form critical components in our... 

The performance of cellulase and amylase immobilized on siliceous supports was investigated. Enzyme uptake onto the support depended on the enzyme source and immobilization conditions. For amylase, the uptake ranged between 20 and 60%, and for cellulase, 7-10%. Immobilized amylase performance was assessed by batch kinetics in 100-300 g/L of com flour at 65°C. Depending on the substrate and enzyme loading, between 40 and 60% starch conversion was obtained. Immobilized amylase was more stable than soluble amylase. Enzyme samples were preincubated in a water bath at various temperatures, then tested for activity. At 105°C, soluble amylase lost -55% of its activity, compared with -30% loss for immobilized amylase. The performance of immobilized cellulase was evaluated from batch kinetics in 10 g/L of substrate (shredded wastepaper) at 55°C. Significant hydrolysis of the wastepaper was also observed, indicating that immobilization does not preclude access to and hydrolysis of insoluble cellulose. 

Kinetics studies were conducted at 55°C in a jacketed batch reactor. Shredded wastepaper (10 g / L) was added to 500 mL or 1L of citrate buffer, pH 4.8, and heated to the assay temperature. A specified quantity of either soluble or immobilized cellulase was added to the reactor to initiate hydrolysis. Samples were collected at regular intervals over 30-60 min, and centrifuged to separate solids. The DNS assay (4) was used to detect sugars formed during hydrolysis experiments. The supernatant from the centrifuge tube and the DNS solution were mixed and cooked for exactly 5 min in boiling water. Finally, the sample was transferred to a methacrylate cuvet, and its absorbance was measured at 540 nm. 

The widespread use of papers has created an enormous amount of wastepaper however, it is not easy to recycle this resource because of the high cost of its utilization process. In the past, recycled wastepaper was used only two to three times before the fibers became unacceptably short (1). This wastepaper can be used in the bioethanol process as inexpensive... 

Ethanol (ethyl alcohol) can be produced from a wide variety of feedstocks, including wood, wastepaper, and crop residues. Ethanol produced from plant biomass is also known as bioethanol. The production of bioethanol from plant biomass involves the fermentation of pulped, mashed, or juiced plant material by yeasts and bacteria (Wiselogel et al., 1996). 

De-inking of wastepaper Fatty alcohol ethoxylates Wetting/flotation... 

Worldwide, approximately 38 percent of wastepaper is recycled however, the rate of recycling varies between countries with the United States at a 45 percent recycle rate. The United States is a major exporter of wastepaper, with the majority going to fiber-poor countries such as Korea and Japan that have much less virgin fiber. 

There are a wide range of different grades of wastepaper available, depending on the source and the extent of separation. As the name implies, wastepaper designated as direct pulp substitutes is utilized with little treatment before reslushing in a hydrapulper. The direct pulp substitutes are the highest grade of wastepaper. 

For us, the most exciting part of the early stages of the work was the continual flow of ideas (usually written in indecipherable handwriting on the back of torn-off scraps of old manuscripts ), which regularly arrived on our desks. Most of these, it has to be said, were stillborn, and for all kinds of reasons ended up in the wastepaper bin. However, within such a multitude were ideas destined to become seminal. Look-... 

Keywords Concrete form, dry process defibrator, lignin, ozone treatment, tropical rainforest, wastepaper. 

Newsprints were first cut to the size 12x3 mm by the use of a commercial shredder and then subjected to FS mill (Fibsonic mill) which was developed by Kobe steel Co., Ltd. and VMC Co., Ltd.. Going through this procedure, newsprints wastepapers were well defibrated to single fibers. In the pulp and paper industry, wastepapers are usually defibrated by the wet process. But, in this study the dry defibrating process was applied so as not to produce any polluted effluents. 

Enzymatic hydrolysis of cellulose appears to be more economically attractive than chemical hydrolysis. [59]. Regardless of hydrolysis method, cellulose opens up the possibility to use of all kinds of farm wastes, straw, sawdust, wastepaper, etc., to produce sugars for fermentation ethanol. 

U.S. Pat. No. 4,339,363 (July 13, 1982). Y. Nakagima. Composite material compositions using wastepaper and method of producing same. 

TABLE 10.9 The linear coefficient of thermal expansion-contraction for LDPE and HDPE filled with cellulose fiber (wastepaper). The published article [2] indicated only the absolute expansion values (in mm) per 1°C, without providing the size (length) of the samples. It was assumed that all the samples were of 60 mm in length, and the data were recalculated to CTE (1/°F)... 

Printed with a renewable-source ink on paper containing at least 50% wastepaper, including 20% postconsumer waste... 

Fukazawa, H., Hoshino, K., Shiozawa, T., Matsushita, H., and Terao, Y., Identification and quantification of chlorinated bisphenol A in wastewater from wastepaper recycling plants, Chemosphere, 44, 973-979, 2001. 

---