Application of wood flour spacers for increasing OCC solid content in wet pressing process (II)

The combined PU spray and wet pressing process allows the manufacture of parts with high lightweight potential. The process can be used for the production of sandwich parts with compact continuous fiber reinforced PU outer layers and a process integrated formation of the foam core. Compared with established production processes for structural sandwich parts, the integration of the foam core formation in a wet pressing process is highly efficient and economical especially for complex structural parts.

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Interpreting process data of wet pressing process. Part 1: Theoretical approach

Journal of Composite Materials ◽

10.1177/0021998315604728 ◽

2015 ◽

Vol 50 (17) ◽

pp. 2399-2407 ◽

Cited By ~ 9

Author(s):

Jana Bergmann ◽

Hans Dörmann ◽

Rüdiger Lange

Keyword(s):

Theoretical Approach ◽

Process Data ◽

Pressing Process ◽

Wet Pressing

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The Influence of Different Wood Aggregates on the Properties of Geopolymer Composites

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.723.74 ◽

2016 ◽

Vol 723 ◽

pp. 74-79 ◽

Cited By ~ 3

Author(s):

Siti Noorbaini Sarmin

Keyword(s):

Fly Ash ◽

Wood Flour ◽

Wood Fiber ◽

Solid Content ◽

Solid Ratio ◽

Wood Particles ◽

Different Types ◽

Alkaline Activator ◽

Class F Fly Ash ◽

Geopolymer Composites

This paper aims to study the effect of different types of wood aggregates on properties of geopolymer composites. Class F fly ash with 30% substitution of metakaolin was used as an alumino-silicates source for the production of geopolymer composites. Wood particles, wood flour, and wood fiber were added to fly ash and metakaolin-based geopolymers at 10% solid content as reinforced materials. 14M NaOH in combination with Na2SiO3 was used as the alkaline activator with a liquid-to-solid ratio of 1.33:2.00. The specimen without wood aggregates was also prepared as a reference for comparison with specimens containing wood aggregates. All specimens were cured at 20°C for 28 days until the day of characterization. It was observed that the incorporation of different types of wood aggregates has influenced their properties. The highest compressive strength of about 38.4 MPa was achieved for the sample containing wood flour. Besides, the density and water absorption of geopolymer composites reacted differently by using different types of wood aggregates. It is demonstrated that size and shape of wood aggregates influence the properties of geopolymer composites.

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Energy saving in papermaking by application of hybrid calcium carbonate

BioResources ◽

10.15376/biores.16.3.5011-5023 ◽

2021 ◽

Vol 16 (3) ◽

pp. 5011-5023

Author(s):

Min Woo Lee ◽

Sun Young Jung ◽

Yung Bum Seo

Keyword(s):

Tensile Strength ◽

Calcium Carbonate ◽

Energy Savings ◽

Solid Content ◽

Pressing Pressure ◽

Ionic Polymers ◽

Paper Properties ◽

Paper Drying ◽

Ghg Reduction ◽

Wet Pressing

Hybrid calcium carbonate (HCC) is prepared by pre-flocculating calcium oxide and ground calcium carbonate (GCC) with ionic polymers, and by injecting carbon dioxide to the pre-flocculated flocs until termination of the reaction at neutral pH. When used in papermaking, HCC gave higher bulk, higher stiffness, and higher tensile strength than GCC did. Furthermore, when higher wet pressing pressure was applied to the paper containing HCC, higher solid content was achieved with still better stiffness, smoothness, and tensile strength in comparison with the paper containing GCC. Actually, very high bulk of the HCC containing paper was compromisingly reduced to obtain high solid content by applying higher wet pressing pressure. Higher solid content achieved by combination of HCC technology and higher wet pressing pressure resulted in paper drying energy savings of more than 10%, while a high quality of all the essential printing paper properties was maintained. Drying energy savings may contribute to greenhouse gas (GHG) reduction and lowering of the paper production cost.

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The Influence of Freezing and Thawing on the Yield and Energy Consumption of the Celeriac Juice Pressing Process

Processes ◽

10.3390/pr8030378 ◽

2020 ◽

Vol 8 (3) ◽

pp. 378 ◽

Cited By ~ 1

Author(s):

Rafał Nadulski ◽

Zbigniew Kobus ◽

Tomasz Guz

Keyword(s):

Solid Content ◽

Raw Material ◽

Process Efficiency ◽

Apium Graveolens ◽

Soluble Solid Content ◽

Juice Quality ◽

Freezing And Thawing ◽

Optimal Method ◽

Pressing Process ◽

Soluble Solid

The aim of this study is to indicate the influence of pretreatment, consisting of grinding vegetables and then freezing and thawing the raw material before pressing on the process efficiency and quality of obtained juice. The subject of the research was celeriac root (Apium graveolens L) of the Edward variety. Juice pressing was carried out in a laboratory basket press. The pressing yield and specific energy were values characterizing the pressing process, while pH and the extracted content in the juice were used to assess the juice quality. The experiment was performed according to three procedures. In each of them, the ground celeriac root (pulp or chips) was initially pretreated through freezing and thawing and then pressed twice. Among the examined methods of obtaining juice, the most beneficial method was pressing juice from the pulp, then freezing and thawing the pomace obtained in the first cycle, and finally, pressing the pomace. It is an energy-optimal method and guarantees a high pressing yield as well as obtaining juice with a higher soluble solid content than during the process of pressing chips.

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Upscaling of foam forming technology for pilot scale

TAPPI Journal ◽

10.32964/tj18.8.461 ◽

2019 ◽

Vol 18 (8) ◽

Cited By ~ 1

Author(s):

JANI LEHMONEN ◽

TIMO RANTANEN ◽

KARITA KINNUNEN-RAUDASKOSKI

Keyword(s):

Production Efficiency ◽

Strength Loss ◽

Pilot Scale ◽

Foam Density ◽

Forming Process ◽

Production Scale ◽

Forming Technology ◽

Wet Pressing ◽

Foam Forming ◽

Board Industry

The need for production cost savings and changes in the global paper and board industry during recent years have been constants. Changes in the global paper and board industry during past years have increased the need for more cost-efficient processes and production technologies. It is known that in paper and board production, foam typically leads to problems in the process rather than improvements in production efficiency. Foam forming technology, where foam is used as a carrier phase and a flowing medium, exploits the properties of dispersive foam. In this study, the possibility of applying foam forming technology to paper applications was investigated using a pilot scale paper forming environment modified for foam forming from conventional water forming. According to the results, the shape of jet-to-wire ratios was the same in both forming methods, but in the case of foam forming, the achieved scale of jet-to-wire ratio and MD/CD-ratio were wider and not behaving sensitively to shear changes in the forming section as a water forming process would. This kind of behavior would be beneficial when upscaling foam technology to the production scale. The dryness results after the forming section indicated the improvement in dewatering, especially when foam density was at the lowest level (i.e., air content was at the highest level). In addition, the dryness results after the pressing section indicated a faster increase in the dryness level as a function of foam density, with all density levels compared to the corresponding water formed sheets. According to the study, the bonding level of water- and foam-laid structures were at the same level when the highest wet pressing value was applied. The results of the study show that the strength loss often associated with foam forming can be compensated for successfully through wet pressing.

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Increased dryness after pressing and wet web strength by utilizing foam application technology

TAPPI Journal ◽

10.32964/tj15.11.731 ◽

2016 ◽

Vol 15 (11) ◽

pp. 731-738 ◽

Cited By ~ 1

Author(s):

KARITA KINNUNEN-RAUDASKOSKI ◽

KRISTIAN SALMINEN ◽

JANI LEHMONEN ◽

TUOMO HJELT

Keyword(s):

Tensile Strength ◽

Guar Gum ◽

Paper Industry ◽

Reference Sample ◽

Strength Properties ◽

Cellulose Microfibrils ◽

Application Technology ◽

Ethylene Vinyl Alcohol ◽

Wet Pressing ◽

Web Strength

Production cost savings by lowering basis weight has been a trend in papermaking. The strategy has been to decrease the amount of softwood kraft pulp and increase use of fillers and recycled fibers. These changes have a tendency to lower strength properties of both the wet and dry web. To compensate for the strength loss in the paper, a greater quantity of strength additives is often required, either dosed at the wet end or applied to the wet web by spray. In this pilot-scale study, it was shown how strength additives can be effectively applied with foam-based application technology. The technology can simultaneously increase dryness after wet pressing and enhance dry and wet web strength properties. Foam application of polyvinyl alcohol (PVA), ethylene vinyl alcohol (EVOH), carboxymethyl cellulose (CMC), guar gum, starch, and cellulose microfibrils (CMF) increased web dryness after wet pressing up to 5.2%-units compared to the reference sample. The enhanced dewatering with starch, guar gum, and CMF was detected with a bulk increase. Additionally, a significant increase in z-directional tensile strength of dry web and and in-plane tensile strength properties of wet web was obtained. Based on the results, foam application technology can be a very useful technology for several applications in the paper industry.

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APLIKASI PROSES DIGESTASI ANAEROBIK LUMPUR BIOLOGI INSTALASI PENGOLAHAN AIR LIMBAH INDUSTRI KERTAS

JURNAL SELULOSA ◽

10.25269/jsel.v4i02.64 ◽

2014 ◽

Vol 4 (02) ◽

Author(s):

Rina S. Soetopo ◽

Sri Purwati ◽

Henggar Hardiani ◽

Mukharomah Nur Aini ◽

Krisna Adhitya Wardhana

Keyword(s):

Oxygen Demand ◽

Total Solid ◽

Pilot Scale ◽

Organic Content ◽

Solid Content ◽

Uasb Reactor ◽

Anaerobic Sludge ◽

Organic Loading ◽

Total Solid Content ◽

Average Value

A continuous pilot scale study has been conducted to investigate the effectiveness of anaerobic digestion of biological sludge. The sludge has a total solid content of 0.53% - 1.1%, pH of 7.20 to 7.32. Its organic content is about 97 %, The research were conducted in two stages, which are acidification (performed in 3 m3 the Continously Stirred Tank Reactor/CSTR at pH of 5.5 to 6.0) and methanation (performed in 5 m3 the Up Flow Anaerobic Sludge Blanket/UASB reactor at pH 6.5 to 7.0). The retention time (RT) was gradually shortened from 6 days to 1 day for acidification and from 8 days to 2 days for methanation. The results showed that operating the CSTR at the RT of 1 day and the organic loading of 8.23 g Volatile Solid (VS)/m3.day could produce Volatile Fatty Acid (VFA) at an average value of 17.3 g/kg VS.day. Operating the UASB reactor at the RT of 2 days and the organic loading (Chemical Oxygen Demand/COD) of 2.4 kg COD/m3.day could produce biogas at an average value of 66.3 L/day, with an average methane content of 69.9%, methane rate of 0.17 L CH4/g COD reduction or 19.06 L CH4/kg VS. Furthermore, methanation could reduce COD at an average value of 51.2 %, resulting in the effluent average value of COD filtrate and COD total of 210.1 mg/L and 375.2 mg /L, respectively.Keywords: acidification, methanation, CSTR, UASB, biogas ABSTRAKPercobaan digestasi anaerobik lumpur IPAL biologi industri kertas secara kontinyu skala pilot telah dilakukan di industri kertas dengan tujuan mengkaji efektivitas proses digestasi anaerobik dalam mengolah lumpur tersebut. Lumpur yang digunakan memiliki total solids sekitar 0,53% – 1,1%, pH netral (7,20 – 7,32) dengan komponen utama senyawa organik sekitar 97%. Percobaan dilakukan dalam dua tahap yaitu asidifikasi dalam reaktor CSTR berkapasitas 3 m3 pada pH 5,5 – 6,0 dan metanasi dalam reaktor UASB berkapasitas 5 m3 pada pH 6,5 – 7,0. Percobaan dilakukan dengan waktu retensi yang dipersingkat secara bertahap dari 6 hari ke 1 hari untuk proses asidifikasi dan dari 8 hari ke 2 hari untuk proses metanasi. Hasil percobaan menunjukkan bahwa pengoperasian reaktor CSTR dengan waktu retensi 1 hari dan beban organik 8,3 g VS/m3.hari dapat menghasilkan VFA rata-rata 17,3 g/kg VS.hari dengan kisaran 8,36 – 30,59 g/kg VS.hari, sedangkan pengoperasian reaktor UASB pada waktu retensi 2 hari dan beban organik 2,4 kg COD/m3.hari dapat menghasilkan biogas rata-rata 66,3 L/hari dengan kadar metana rata-rata 69,9% atau 0,17 L CH4/g COD reduksi atau 19,06 L CH4/kg VS. Selain itu proses metanasi dapat menurunkan COD terlarut rata-rata 51,2%, dengan konsentrasi efluen COD terlarut rata-rata 210,1 mg/L dan COD total rata-rata 375,2 mg/L.Kata kunci: asidifikasi, metanasi, CSTR, UASB, biogas

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