Everything About Wood

Tuesday, 17 May 2016

Chemical Pretreatments of Wood Chips Prior to Alkaline Pulping - A Review of Pretreatment Alternatives, Chemical Aspects of the Resulting Liquors, and Pulping Outcomes

BioResourcers

Chemical Pretreatments of Wood Chips Prior to Alkaline Pulping - A Review of Pretreatment Alternatives, Chemical Aspects of the Resulting Liquors, and Pulping Outcomes

Joni Tapani Lehto, Raimo Juhani Alén

Abstract

The chemical industry is being forced to evaluate new strategies for more effective utilization of renewable feedstocks to diminish the use of fossil resources. In this literature review, the integration of both acidic and alkaline pretreatment phases of hardwood and softwood chips with chemical pulping is discussed. Depending on the pretreatment conditions, high-volume sulfur-free fractions with varying chemical compositions can be produced. In case of acidic pretreatments, the major products include carbohydrates (mono-, oligo-, and polysaccharides), whereas under alkaline (i.e., aqueous NaOH) pretreatment conditions, the sulfur-free fractions of aliphatic carboxylic acids, lignin, and extractives are primarily obtained. All these fractions are potentially interesting groups of compounds and can be used in a number of applications. Finally, the effects of pretreatments on pulping are also considered. Although it is believed that there are important advantages to be gained by integrating this type of renewable raw material-based production, in particular, with kraft pulping, sulfur-free pulping methods such as soda-AQ and oxygen/alkali delignification processes are also briefly discussed.

Keywords

Autohydrolysis; Biorefining; Biochemicals; By-products; Carbohydrates; Delignification; Extractives; Hydrolysis; Lignin; Organic acids; Pretreatment; Pulping

Full Text: PDF

Welcome to BioResources! This online, peer-reviewed journal is devoted to the science and engineering of biomaterials and chemicals from lignocellulosic sources for new end uses and new capabilities. The editors of BioResources would be very happy to assist you during the process of submitting or reviewing articles. Please note that logging in is required in order to submit or review articles. Martin A. Hubbe, (919) 513-3022, hubbe@ncsu.edu; Lucian A. Lucia, (919) 515-7707, lucian.lucia@gmail.com URLs: bioresourcesjournal.com; http://ncsu.edu/bioresources ISSN: 1930-2126

For further details log on website :

http://ojs.cnr.ncsu.edu/index.php/BioRes/article/view/BioRes_10_4_Review_Lehto_Chemical_Pretreatments_Wood_Chips

Paper or Plastic? Yes, but Not as a Mixture

BioResourcers

Paper or Plastic? Yes, but Not as a Mixture

Martin A. Hubbe

Abstract

As expressed by the chorus lyrics of a song by Dan Einbender, “it really isn’t garbage ‘til you mix it all together. It really isn’t garbage ‘til you throw it away. Separate your paper, plastic, compost, glass and metal. Then you get to use it all another day.” It’s worth paying attention to these lyrics once again in the face of yet another type of product that is starting to show up in stores. Extruded sheets of polyethylene (no. 2 plastic) with as much as 80% ground calcium carbonate content are being sold as “paper”. Calcium carbonate is widely used as a component of real paper. However, it rubs me the wrong way when the word “paper” is being used to refer to something that has no fibers in it and is not formed on a screen and dried. My more serious concern is that such materials, if they become widely used, have the potential to contaminate paper recycling operations.

Keywords

Paper recycling; Plastic contamination; Stone paper; Extrusion; Recyclability

Effect of Surface Treatment on the Physical, Chemical, and Mechanical Properties of Palm Tree Leaf Stalk Fibers

BioResourcers

Effect of Surface Treatment on the Physical, Chemical, and Mechanical Properties of Palm Tree Leaf Stalk Fibers

Arun Kumar Rout, Jnanaranjan Kar, Dipak Kumar Jesti, Alekh Kumar Sutar

Abstract

A new class of leaf stalk fibers of the palm tree were extracted and treated with a 5% NaOH solution for 1 h, 2 h, 6 h, and 12 h. The treated fibers were then characterized by tensile strength testing, chemical analysis, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and solid state NMR. The tensile strength of the fibers was improved with an alkali treatment, and the 6 h treatment resulted in the maximum fiber strength. The maximum cellulose content was present in the 6 h-treated fibers; cellulose content was reduced with a longer treatment (12 h). Similarly, SEM, FTIR, XRD, and NMR confirmed the removal of hemicelluloses from the raw fiber surface and the formation of new hydrogen bonds between the cellulose fibril chains with respect to the duration of the treatment. The 5% alkali treatment also improved the fiber density from 0.85 gm/cc (raw fiber) to 1.05 gm/cc, 1.13 gm/cc, 1.17 gm/cc, and 1.25 gm/cc after the 1 h, 2 h, 6 h, and 12 h treatments, respectively.

Keywords

Palm fiber; Alkali treatment; Tensile strength; XRD; FTIR; SEM; NMR

For further details log on website :

http://ojs.cnr.ncsu.edu/index.php/BioRes/article/view/BioRes_11_2_4432_Rout_Surface_Treatment_Palm_Tree_Leaf_Stalk

The Effect of Wood Alignment on Wood Grinding – Part 1: Properties of Pulp and Fines Revealed in the Grinding Mechanism

BioResourcers

The Effect of Wood Alignment on Wood Grinding – Part 1: Properties of Pulp and Fines Revealed in the Grinding Mechanism

Erkki Tapani Saharinen, Airi Särkilahti, Lauri Ilmari Salminen, Sabine Heinemann

Abstract

In industrial wood grinding, logs are pressed against a rotating stone, with the logs and fiber axis parallel to the axis of the stone. The objective of this study is to clarify how the wood alignment affects the process and pulp properties. In this research, wood blocks were fed into a laboratory grinder with various alignments in relation to the surface of the grinding stone. The effects of the alignment on the properties of the pulp and the amount and quality of fines were measured. A grinding mechanism was proposed. The results show that the pulp quality is very sensitive to the angle between the stone surface and the log. In gentle refining, the fiber structure is loosened by fatigue before it is bent on the surface; pressure pulses produce fibrillar material, and fibers develop toward having good bonding ability. In forced grinding, the process is “violent”, and the fiber wears and becomes crushed immediately on the surface into small particles with low bonding ability.

Keywords

Groundwood; Grinding angle; Wood alignment; Fiber properties; Norway spruce

Which Gets Rid of More Belly Fat: Running or Cycling?

Whether you're looking to fit into an old pair of skinny jeans or to improve your health, cardiovascular exercises like running and cycling are proven fat-loss methods. When trying to lose belly fat, however, the exercise you choose is less important than the health benefits that it provides. While both running and cycling are effective at decreasing your waist size, losing weight is the only sure method of losing belly fat.

man and woman running on paved street Photo Credit Maridav/iStock/Getty Images.

Belly fat isn't the obvious layer of fat that lies just under your skin on your abdomen. Belly fat is the layer of fat between your abdominal muscles, surrounding your internal organs. Because you can't spot reduce to remove either the outer layer or deep internal layer of fat, you must lose weight to lose belly fat. A combination of a healthy diet and an exercise program, which includes aerobic exercises such as running and cycling, is the only effective method of reducing your belly fat.

Although running is effective method for reducing your overall body fat, including belly fat, it is a high-impact activity and may lead to foot, leg and hip injuries. If you have a history of knee or ankle problems, you might find yourself unable to train for long periods. While you may not burn as many calories in a single session, riding a bicycle or stationary bicycle is low-impact and easy on the joints. If you experience knee pain while running or are recovering from an injury, your doctor may recommend cycling to build up the muscles around your knees and maintain your exercise routine.

Depending on the intensity level of your exercise routine, running and cycling are nearly neck and neck when burning calories. A 155-pound person may burn as many as 614 calories in one-half hour when running at 10 mph or cycling at more than 20 mph. However, when running or jogging at a moderate 5 mph, you'd burn 298 calories, while taking a moderate pace on a stationary bicycle only burns 260 calories for the same one-half hour workout.

Running requires more stamina than cycling. If you have trouble keeping the same pace for more than 10 minutes while running, you might have more success with cycling. Maintaining a raised heart rate for at least 30 minutes while cycling will lead to more calories burned and increased overall fat loss. Because you can only lose belly fat by losing fat over your entire body, it's important to participate in physical activities for a minimum of 150 minutes per week, or 300 minutes weekly if you're trying to lose weight, according to the Centers for Disease Control and Prevention.

To lose belly fat, you must burn more calories than you consume. Adding a healthy, low-calorie eating plan to your goal of losing belly fat helps you lose weight faster than exercise alone. While running and cycling are both viable fat-loss methods, they work only if you commit to a regular exercise routine. Choose the one that you enjoy the most, or alternate running and cycling to keep yourself from becoming bored with the same daily routine.

www.livestrong.com

Low Carb Vegan Breakfast Ideas

Typical breakfasts on a low-carbohydrate diet can rely heavily on eggs, meat and cheese, but a vegan diet includes only plant-based foods. You can still make a healthy, low-carbohydrate breakfast without using eggs, milk products or meat. To help you meet your daily nutrient requirements, focus on nutrient-dense options, such as vegetables, nuts and soy products, for your low-carbohydrate vegan breakfast.

A tofu scramble is a vegan alternative to scrambled eggs and omelets for breakfast. A half-cup of firm tofu contains 5 grams of carbohydrates, and each half-cup of cooked vegetables adds another 5 grams. Choose fortified tofu to get the calcium you need to support strong bones. Tofu scrambles have many possible variations to help you prevent boredom. Try combinations such as eggplant and green onions, tomatoes and zucchini or spinach and mushroom. Flavor the scramble with low-sodium soy sauce or salsa, and add sesame seeds for protein and healthy fats.

A smoothie can be a portable breakfast option on a low-carbohydrate vegan diet. Make it with ice and unsweetened soy milk or plain soy yogurt. A cup of soy milk contains 4 grams of carbohydrates. To flavor and sweeten your smoothie naturally, add fresh or frozen fruit, such as strawberries, with 15 grams of carbohydrates in 1.25 cups, or a peach, which has 15 grams of carbohydrates. Use a tablespoon of peanut butter or almond butter to thicken the smoothie, and add protein and unsaturated fats.

Stuffed tomatoes can be a high-protein, low-carbohydrate vegan breakfast option if you use a soy-based substitute for ground beef. A cup of meatless substitute contains 7 grams of carbohydrates and provides 15 grams of protein, or 30 percent of the daily value for protein based on a 2,000-calorie diet. A meatless ground beef substitute is also high in iron, an essential mineral for preventing anemia. It provides 4.3 milligrams per cup, or 24 percent of the daily value based on a 2,000-calorie diet. Cook the soy crumbles with chopped onion, garlic and Italian seasoning, place the mixture on tomato halves and bake the tomatoes.

Fortified dairy products, such as milk, cheese and yogurt, are important sources of calcium and vitamin D for most Americans. The publication "Dietary Guidelines for Americans, 2010" suggests that those who do not consume dairy products focus on alternative sources, such as soy milk, to meet their calcium needs. Try melting a soy-based cheese substitute on black or pinto beans, or have soy yogurt with walnuts and a small apple.

Soy products are sources of high-quality protein, and they can be meat substitutes on a low-carbohydrate vegan diet. The University of Michigan explains that fortified soy products also provide calcium, dietary fiber, iron, potassium and zinc. For breakfast, stir-fry soybeans or tofu with vegetables, such as bell peppers, broccoli and onions. Serve this dish on its own, or make a low-carbohydrate breakfast wrap using large leaves of lettuce or cooked cabbage instead of a tortilla. You can also pile the dish onto grilled eggplant slices to make open-faced sandwiches.

www.livestrong.com

Greene & Greene Furniture eBook Poems of Wood & Light

THE WOODWORKING DESIGN COLLECTION - ONLY 69 LEFT !

By David Mathias

Format: eBook

Greene & Greene Furniture blends Asian influences with Arts & Crafts concepts to produce truly unique pieces of functioning art. This book looks closely at the details and influences in the work of Greene & Greene as well as their design philosophy in houses, furniture and decorative arts. The author pulls together disparate influences including the Arts & Crafts movement, Japanese architecture and philosophy, Chinese furniture and an overlooked but crucial element in their work; the environment and topography of California. Included are many new photographs and historical photos to provide context and perspective.

About the Author:

David Mathias is an author and photographer with a background in computer science. He was educated at the University of Delaware (B.S.) and Washington University in St. Louis (M.S., D.Sc.). He was a college instructor for fourteen years before abandoning computer science, academia and a paycheck for the full-time pursuit of writing. David has published articles in Popular Woodworking, Woodwork, Style 1900 and American Bungalow. He currently lives near Vevey, Switzerland with his wife Patty and sons Dylan and Zachary.

SKU	Y3144
Author/Speaker/Editor	David Mathias
File Type	PDF
Format	eBook
ISBN 13	9781440311130

For further information log on website :

http://www.shopwoodworking.com/popular-woodworking-1995-1999-cd?source=igodigital

Effects of hardener type, urea usage and conditioning period on the quality properties of particleboard

Materials & Design

April 2014, Vol.56:91–96, doi:10.1016/j.matdes.2013.10.078

İlkay Atar^a

Gökay Nemli^a

Nadir Ayrilmis^b,^,

Mehmet Baharoğlu^c

Bünyamin Sarı^a

Selahattin Bardak^d

aKaradeniz Technical University, Faculty of Forestry, Trabzon, Turkey
bIstanbul University, Faculty of Forestry, Istanbul, Turkey
cRecep Tayyip Erdoğan University, Vocational School of Technical Sciences, Rize, Turkey
dArtvin Çoruh University, Faculty of Forestry, Artvin, Turkey

Received 31 August 2013. Accepted 27 October 2013. Available online 7 November 2013.

Highlights

•
Hardner type, urea usage, and conditioning period of particleboard were investigated.
•
Best properties were obtained from panels manufactured with ammonium chloride.
•
The urea usage positively affected the formaldehyde emission.
•
Increasing conditioning period of panels resulted in better quality properties

Abstract

The effects of hardener type (ammonium chloride, ammonium sulphate and aluminium sulphate), urea usage (with urea and without urea), and conditioning period (one day and one month) of the particleboard on the physical (thickness swelling), mechanical (modulus of rupture, modulus of elasticity and internal bond strength), surface properties, and formaldehyde emission of particleboard and acidity of the wood particles were investigated. The hardener type was found to be effective all of the properties of particleboard. The pH of the wood particle with the urea was slightly higher than that of particles without urea.

The lowest pH value for the resinated wood particles was obtained from ammonium chloride, followed by ammonium sulphate and aluminium sulphate, respectively. The best quality properties were obtained from the particleboards manufactured with ammonium chloride, followed by particleboard made with the ammonium sulphate and aluminium sulphate, respectively. The urea usage significantly decreased the formaldehyde emission of the particleboards while it slightly decreased the mechanical properties and increased thickness swelling. Increasing conditioning period of the particleboards from one day to one month improved the quality properties.

Keywords

Particleboard

Hardener type

Urea usage

Conditioning period

Formaldehyde emission

Surface roughness

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Corresponding author. Address: Department of Wood Mechanics and Technology, Forestry Faculty, Istanbul University Bahcekoy, 34473 Istanbul, Turkey. Tel.: +90 (212) 226 1100x25083; fax: +90 (212) 226 1113.

For further details log on website :

http://www.sciencedirect.com/science/article/pii/S0261306913010212

Original Articles A Model of Drying Kinetics of Acacia mangium Wood at Different Temperatures

DOI:: 10.1080/07373937.2013.829855

Wan Noor Aidawati Wan Nadhari^a, Rokiah Hashim^a^*, Mohammed Danish^a, Othman Sulaiman^a & Salim Hiziroglu^b

pages 361-370

Publishing models and article dates explained

Published online: 24 Jan 2014

Drying Technology: An International Journal

Volume 32, Issue 3, 2014

Abstract

The objective of this study was to determine the isothermal drying kinetics of Acacia mangium wood blocks by employing a relative humidity-controlled drying chamber. A model was developed based on solution of Fick's second law and evaluated through the coefficient of determination (R²), sum of square error (SSE), root mean square error (RMSE), and reduced chi-square (χ ²). This model was compared to semi-theoretical models which are commonly used to describe the drying behavior of biomass in previous studies. The porosity and shrinkage characteristics of dried specimens were also evaluated. Based on the findings in this work, it was determined that the proposed model resulted in an excellent fit with experimental data for all four drying temperature levels of 30, 35, 40, and 45^∘C to describe the isothermal drying kinetics of Acacia mangium . It appears that volumetric shrinkage of the samples decreased quadratically with decreasing moisture ratio. The activation energy of the drying process was determined to be 41.07 kJ/mol.

Author affiliations

^a Division of Bioresource, Paper and Coatings Technology, School of Industrial Technology , Universiti Sains Malaysia , Penang , Malaysia
^b Department of Natural Resource Ecology and Management , Oklahoma State University , Stillwater , Oklahoma , USA

For further details log on website :

http://www.tandfonline.com/doi/full/10.1080/07373937.2013.829855#abstract

Improved performance of compressed oil palm trunk prepared from modified pre-steaming technique

SPRINGERLINK

Original Article

Journal of the Indian Academy of Wood Science

pp 1-7

First online: 28 November 2015

Journal of the Indian Academy of Wood Science

Nurjannah Salim

, Rokiah Hashim

, Othman Sulaiman

, Mazlan Ibrahim

, Mohammed Nasir

, Masatoshi Sato

, Tomoko Sugimoto

, Salim Hiziroglu

Abstract

Malaysia is one of the biggest producers of palm oil in the world but the oil palm wood is considered as waste after final harvesting. A huge and inexpensive availability of oil palm trunk (OPT) can be a sustainable source of alternative wood for various structural applications, if it can be utilized. The objective of this work was to prepare a steamed treated compressed OPT lumber and evaluate the physical, chemical and biological properties of modified wood. In this technique OPT samples were steamed at temperature 130 °C for 2 h before being compressed at high temperature. Wettability of the steam compressed OPT was analysed by contact angle method and observed it was reduced as compared to simply compressed OPT. Samples were exposed to outdoor conditions to evaluate their resistance against biological deterioration. Microscope and X-ray diffraction analyses of the samples were also carried out. Steamed compressed OPTs exhibited improved resistance against biodegradation probably due to the increase of extractives in it, as compared to simply compressed OPTs. It seems that steaming in combination of compressing at high temperature would enhance the properties of OPTs.

Keywords

Biodegradability Contact angle Soil burial test Crystallinity

Title

Improved performance of compressed oil palm trunk prepared from modified pre-steaming technique

Journal

Journal of the Indian Academy of Wood Science

DOI

10.1007/s13196-015-0155-1

Print ISSN

0972-172X

Online ISSN

0976-8432

Publisher

Springer India

Additional Links

Topics

Keywords

Biodegradability
Contact angle
Soil burial test
Crystallinity

Authors

Author Affiliations

1. Faculty of Industrial Sciences and Technology, Universiti Malaysia Pahang, Lebuhraya Tun Razak, 26300, Gambang, Kuantan, Pahang, Malaysia
2. Division of Bioresource, Paper and Coatings Technology, School of Industrial Technology, Universiti Sains Malaysia, 11800, Minden, Penang, Malaysia
3. Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1, Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
4. Japan International Research Center for Agricultural Sciences, 1-1, Ohwashi, Tsukuba, Ibaraki, 305-8686, Japan
5. Forestry and Forest Products Research Institute, 1 Matsunosato, Tsukuba, Ibaraki, 305-8687, Japan
6. Department of Natural Resource Ecology and Management, Oklahoma State University, Stillwater, OK, 74078-6013, USA

For further details log on website :

http://link.springer.com/article/10.1007%2Fs13196-015-0155-1

Blog List

Tuesday, 17 May 2016

Chemical Pretreatments of Wood Chips Prior to Alkaline Pulping - A Review of Pretreatment Alternatives, Chemical Aspects of the Resulting Liquors, and Pulping Outcomes

Abstract

Keywords

Paper or Plastic? Yes, but Not as a Mixture

Abstract

Keywords

Effect of Surface Treatment on the Physical, Chemical, and Mechanical Properties of Palm Tree Leaf Stalk Fibers

Abstract

Keywords

The Effect of Wood Alignment on Wood Grinding – Part 1: Properties of Pulp and Fines Revealed in the Grinding Mechanism

Abstract

Keywords

What Belly Fat Is and Isn't

High-Impact vs. Low-Impact Aerobics

Intensity of Exercise

Minimum Exercise Standards

Add a Healthy Diet

Tofu Scramble

Soy Smoothie

Stuffed Tomatoes

Soy-Based Dairy Substitutes

Make a Low-Carbohydrate Breakfast Wrap

By David Mathias

Highlights

Drying Technology: An International Journal

Volume 32, Issue 3, 2014

Author affiliations

Abstract

Keywords