Properties of wood chips for thermomechanical pulp (TMP) production as a function of spout angle

Holzforschung ◽  
2011 ◽  
Vol 65 (6) ◽  
pp. 805-809 ◽  
Author(s):  
Lisbeth M. Hellström ◽  
Per A. Gradin ◽  
Per Engstrand ◽  
Øyvind Gregersen
Keyword(s):  
Energy Consumption ◽  
Patent Application ◽  
Specific Energy Consumption ◽  
Electrical Energy ◽  
Wood Chips ◽  
Thermomechanical Pulp ◽  
Spruce Wood ◽  
Cutting Rate ◽  
Pulp Properties ◽  
The Impact

Abstract Spruce wood chips were produced under well-controlled conditions in a laboratory wood chipper at spout angles of 30°, 40°, and 50° at a cutting rate of 20 m s-1 and with a nominal chip length of 25 mm. The chips were then refined under thermomechanical pulp (TMP) conditions in a pilot refiner plant. The pulp properties such as freeness, average fiber length, and shives content were determined and evaluated as a function of specific energy consumption. For a first stage refining and for a freeness value of 350 ml, a decrease in specific electrical energy consumption could be achieved by performing the wood chipping at a spout angle of 50° as compared to 30° which is the spout angle commonly used. A patent application regarding this method has been filed and is pending. It is realized that a freeness value is not directly indicative of any quality measure, such as, for example tensile index and light scattering coefficient but the obtained results can be interpreted to be promising. Further studies are needed regarding the impact of the modified chipping process.

Spruce fiber properties after high-temperature thermomechanical pulping (HT-TMP)

Holzforschung ◽  
2014 ◽  
Vol 68 (2) ◽  
pp. 195-201 ◽  
Author(s):  
Iina Solala ◽  
Toni Antikainen ◽  
Mehedi Reza ◽  
Leena-Sisko Johansson ◽  
Mark Hughes ◽  
...  
Keyword(s):  
Energy Consumption ◽  
High Temperature ◽  
Matrix Material ◽  
Specific Energy Consumption ◽  
Electrical Energy ◽  
Strength Properties ◽  
Thermomechanical Pulp ◽  
Wall Region ◽  
Fiber Properties ◽  
Thermomechanical Pulping

Abstract Spruce was submitted to high-temperature (150°C–170°C) refining for 2 or 5 min to produce thermomechanical pulp (TMP) fibers with decreased electrical energy consumption. The pulp was characterized in terms of specific energy consumption as well as tensile and surface properties. The fibers from high-temperature TMP contained more surface lignin even if all sample types usually broke at the S1–S2 cell wall region. They also produced significantly weaker paper sheets, whereas their dry zero-span strength did not suffer substantial losses, indicating decreased fiber-fiber bonding. Tensile strength properties were also determined of a bisphenol-A-epichlorohydrin-based epoxy resin mixed with 5% fiber as a test for fiber-matrix compatibility in composite applications. Based on these preliminary results, high-temperature TMP shows potential for composite reinforcement due to its lower tendency to aggregate and its better compatibility with the tested matrix material.

scholarly journals The Analysis of Electrical Energy Consumption of the Impact Screwdriver During Assembly of Fixed Threaded Joints

2017 ◽  
Vol 54 (3) ◽  
pp. 50-57 ◽  
Author(s):  
I. Grinevich ◽  
Vl. Nikishin ◽  
N. Mozga ◽  
M. Laitans
Keyword(s):  
Energy Consumption ◽  
Operating Time ◽  
Electrical Energy ◽  
Operating Mode ◽  
Electrical Energy Consumption ◽  
Impact Mechanism ◽  
Threaded Joints ◽  
Rotor Head ◽  
Product Costs ◽  
The Impact

Abstract The paper deals with the possibilities of reducing the consumption of electrical energy of the impact screwdriver during the assembly of fixed threaded joints. The recommendations related to a decrease in electrical energy consumption would allow reducing product costs but so far there have been no such recommendations from the producers of the tool as to the effective operating regimes of the impact screwdrivers in relation to electrical energy consumption and necessary tightening moment of the nut. The aim of the study is to find out the economical operating mode of the electrical impact screwdriver when assembling fixed threaded joints. By varying the set speed of the rotor head and working time of the impact mechanism, there is an opportunity to determine electrical energy consumption of the tool for the given tightening moment. The results of the experiment show that at the same tightening moment obtained the electrical energy consumption of the impact screwdriver is less at a higher starting set speed of the rotor head but shorter operating time of the impact mechanism than at a lower speed of the rotor head and longer operating time of the impact mechanism.

scholarly journals Review: Reduction of energy consumption in TMP refining through mechanical pre-treatment of wood chips

2010 ◽  
Vol 25 (2) ◽  
pp. 156-161 ◽  
Author(s):  
Dmitri Gorski ◽  
Jan Hill ◽  
Per Engstrand ◽  
Lars Johansson
Keyword(s):  
Energy Consumption ◽  
Pilot Scale ◽  
High Ratio ◽  
Wood Chips ◽  
Chip Size ◽  
Weak Points ◽  
Pulp Properties ◽  
Pre Treatment ◽  
Reduction Of Energy Consumption

Abstract This review covers the effect of mechanical pre-treatment of wood chips on the energy consumption in refining and the quality of pulp. To understand the mechanisms of mechanical pre-treatment, a short description of relevant refining theory and reported effects of pre-treatment on wood morphology is given. Mechanical pre-treatment offers a chance to utilize the energy needed to defibrate chips in a more efficient way, minimizing the cyclic elastic deformations which are the main defibration mechanism in refining. Studies of fibre morphology indicate that compressive pretreatment mechanically introduces favorable weak points in the S1 and S2 fibre walls where defibration proceeds easier upon subsequent refining. Published results which cover the effect of the pretreatment on energy consumption and pulp properties are reviewed. Energy reduction of between 10% and 30% is reported in the literature. High ratio of volumetric compression is necessary. Pressurized conditions are required to ensure that the fibres are not damaged during the pre-treatment. Other effects of compressive pretreatment include a more uniform chip size and moisture content, better penetration of chemicals and removal of extractives from the chips. A list of equipment used for chip pre-compression is provided together with published results of pilot-scale and mill-scale operation.

scholarly journals Intelligent Energy Management Strategy for Automated Office Buildings

Energies ◽  
2019 ◽  
Vol 12 (22) ◽  
pp. 4326 ◽  
Author(s):  
Simplice Igor Noubissie Tientcheu ◽  
Shyama P. Chowdhury ◽  
Thomas O. Olwal
Keyword(s):  
Energy Consumption ◽  
Intelligent System ◽  
Weather Condition ◽  
Electrical Energy ◽  
Integrated System ◽  
Office Buildings ◽  
Photovoltaic System ◽  
Energy Management Strategy ◽  
Significant Saving ◽  
The Impact

The increasing demand to reduce the high consumption of end-use energy in office buildings framed the objective of this work, which was to design an intelligent system management that could be utilized to minimize office buildings’ energy consumption from the national electricity grid. Heating, Ventilation and Air Conditioning (HVAC) and lighting are the two main consumers of electricity in office buildings. Advanced automation and control systems for buildings and their components have been developed by researchers to achieve low energy consumption in office buildings without considering integrating the load consumed and the Photovoltaic system (PV) input to the controller. This study investigated the use of PV to power the HVAC and lighting equipped with a suitable control strategy to improve energy saving within a building, especially in office buildings where there are reports of high misuse of electricity. The intelligent system was modelled using occupant activities, weather condition changes, load consumed and PV energy changes, as input to the control system of lighting and HVAC. The model was verified and tested using specialized simulation tools (Simulink®) and was subsequently used to investigate the impact of an integrated system on energy consumption, based on three scenarios. In addition, the direct impact on reduced energy cost was also analysed. The first scenario was tested in simulation of four offices building in a civil building in South Africa of a single occupant’s activities, weather conditions, temperature and the simulation resulted in savings of HVAC energy and lighting energy of 13% and 29%, respectively. In the second scenario, the four offices were tested in simulation due to the loads’ management plus temperature and occupancy and it resulted in a saving of 20% of HVAC energy and 29% of lighting electrical energy. The third scenario, which tested integrating PV energy (thus, the approach utilized) with the above-mentioned scenarios, resulted in, respectively, 64% and 73% of HVAC energy and lighting electrical energy saved. This saving was greater than that of the first two scenarios. The results of the system developed demonstrated that the loads’ control and the PV integration combined with the occupancy, weather and temperature control, could lead to a significant saving of energy within office buildings.

scholarly journals Experimental and Numerical Investigation of Hard Rock Breakage by Indenter Impact

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Hongxiang Jiang ◽  
Zhiyuan Cai ◽  
Ouguo Wang ◽  
Deguang Meng
Keyword(s):  
Energy Consumption ◽  
Impact Velocity ◽  
Impact Energy ◽  
Specific Energy ◽  
Specific Energy Consumption ◽  
Decisive Role ◽  
Rock Breakage ◽  
Radial Cracks ◽  
The Impact ◽  
Indenter Shape

To investigate the effect of indenter shape, impact energy, and impact velocity on the rock breakage performance, a test device for rock fragmentation by indenter impact was developed to obtain the rock breakage volume, depth, and area under different impact conditions. By comparing the rock breakage volume, depth, area, and specific energy consumption, the results show that indenter shape has a greater influence on the rock breakage performance than that of the impact velocity with the same impact energy, and impact energy plays a decisive role in rock breakage performance with an identical indenter shape and impact velocity. For the lowest to highest specific energy consumption, the order of indenter shape is cusp-conical, warhead, hemispherical, spherical-arc, and flat-top under the same impact energy and velocity, but the cusp-conical indenter is damaged after several impacts. The rock breakage volume, depth, and area all increase with the increase in impact energy, but the effect of the impact velocity could be ignored under the same impact energy. In addition, the rock breakage features of the numerical simulation and experiments are similar, which show that the crushing zone close to the indenter impact point is mainly caused by the high compressive stress, and then radial cracks are caused by the accumulative energy release. The findings of this study will contribute to progress in the performance and efficiency for percussive rock drilling.

scholarly journals TMP properties and refining conditions in a CD82 chip refiner. Part I: Step changes of process variables, description of the tests

2018 ◽  
Vol 33 (1) ◽  
pp. 69-81
Author(s):  
Rita Ferritsius ◽  
Olof Ferritsius ◽  
Jan Hill ◽  
Anders Karlström ◽  
Karin Eriksson
Keyword(s):  
Specific Energy Consumption ◽  
Fibre Length ◽  
Thermomechanical Pulp ◽  
Process Variables ◽  
Negative Effects ◽  
Entropy Model ◽  
Tensile Index ◽  
Pulp Consistency ◽  
Pulp Properties ◽  
Flat Zone

Abstract The study explores how changes in process variables, residence time and pulp consistency in refining influence the pulp properties. The equipment utilized in this study was a conical disc chip refiner (RGP82CD) producing thermomechanical pulp (TMP). The focus was on the ratio between tensile index and specific energy consumption. Pulp properties were measured for composite pulp samples taken from the refiner blow line. Residence times and pulp consistencies were estimated by use of the extended entropy model. This showed that the CD-refiner, with the flat and conical refining zone, has a process performance similar to that of a two-stage refiner set-up, and that the consistency in both refining zones is of high importance. Comparing different periods revealed that even if the values of measured blow line consistency are similar, significant differences in the estimated consistency in the flat zone can prevail. Therefore, only monitoring blow line consistency is not enough. Specifically, it was found that the pulp consistency after the flat zone could be very high, considerably higher than in the blow line, and this could have negative effects on tensile index and fibre length.

scholarly journals Performance analyses on fluidized bed dryer integrated biomass furnace with and without air preheater for paddy drying

2019 ◽  
Vol 10 (3) ◽  
pp. 1555
Author(s):  
M Yahya ◽  
Hendriwan Fahmi ◽  
Syafrul Hadi ◽  
Edison Edison
Keyword(s):  
Energy Consumption ◽  
Fluidized Bed ◽  
Evaporation Rate ◽  
Specific Energy Consumption ◽  
Electrical Energy ◽  
Electrical Energy Consumption ◽  
Moisture Evaporation ◽  
Air Preheater ◽  
Fluidized Bed Dryer ◽  
Average Value

The performance of a fluidized bed dryer integrated biomass furnace with air preheater (FBD with APH) and a fluidized bed dryer integrated biomass furnace without air preheater (FBD without APH) for drying of paddy  have been evaluated. The  FBD with APH and FBD without APH decreased the moisture of paddy from 24% (wet basis) to 14% (wet basis) within 43 and 47 minutes with average temperatures and relative humidities of 59.58 <sup>o</sup>C and 59.14<sup>o</sup>C, and 18.81% and 18.68%, respectively. The drying rate of paddy varied in the range of 0.11 kg/min-0.32 kg/min and 0.10 kg/min- 0.30 kg/min for FBD with APH and FBD without APH, with average values of 0.18kg/min and 0.17kg/min, respectively. The minimum, maximum, and average value specific moisture evaporation rate (SMER) was  0.20 kg/kWh, 0.57 kg/kWh, and 0.31 kg/kWh, respectively for FBD with APH, as well as 0.149 kg/kWh, 0.448 kg/kWh, and 0.252  kg/kWh, respectively, for FBD without APH.  The specific energy consumption (SEC), the specific electrical energy consumption (SEEC), and the specific thermal energy consumption (STEC) were varied from 1.749 kWh/kg to 5.076 kWh/kg, 0.090 kWh/kg to 2.872 kWh/kg, and 0.760 kWh/kg to 2.204 kWh/kg, with average values of 3.528 kWh/kg, 1.96 kWh/kg, and 1.532 kWh/kg, respectively for FBD with APH, as well as from 2.234 kWh/kg to 6.702 kWh/kg, 1.056 kWh/kg to 3.167 kWh/kg, and 1.179 kWh/kg to 3.536 kWh/kg, with average values of 4.391 kWh/kg, 2.075 kWh/kg, and 2.316 kWh/kg, respectively, for FBD without APH. The thermal efficiencies of the FBD with APH and  FBD without APH were varied between 12.4% and 37.93%, and 9.78% and 29.82%, resvectively, with average values of 20.78% and 16.61%. The thermal efficiency of FBD with APH was higher compared to FBD without APH.

scholarly journals Energy Evaluation of the Mechanical Drying of the Grain of Coffea arabica from Honduras

2021 ◽  
pp. 8-14
Author(s):  
Fredy Torres Mejía ◽  
Jhunior Marcía Fuentes ◽  
Juan Torres Mejía ◽  
Flavio Hernández Bonilla ◽  
Ricardo Santos Alemán ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Co2 Emissions ◽  
Coffea Arabica ◽  
Research Work ◽  
Electrical Energy ◽  
Biomass Energy ◽  
Energy Evaluation ◽  
Rotary Dryer ◽  
Reduction Of Co2 ◽  
The Impact

The aim of this research work was to evaluate the methods of mechanical drying of coffee beans (Coffea arabica) from energy evaluations. The control variables were the drying of the grain and energy was used as the response variable, measured in Tonnes of Oil Equivalent (TEP), Barrels of Oil Equivalent (BEP), and Tonnes of Carbon Dioxide Equivalent (Ton CO2eq). The evaluations on the three methods of mechanical coffee drying indicate that the rotary dryer requires 1.0 TEP equivalent to 1.017 kg CO2eqkg-1 in dry parchment coffee (CPS), however, the vertical drying method requires 1.12 TEP (0.616 kg CO2eqkg-1 in CPS) and the static dryer requires 0.5 TEP (0.33 Kg CO2eqkg-1 in CPS). Furthermore, the biomass energy consumption in the rotary dryer is 12.60 MJkg-1, in the vertical dryer it is 7.46 MJkg-1, and the static dryer is 3.91 MJkg-1. These results indicate that the rotary dryer uses 91.95% of the biomass energy, the vertical dryer uses 90.31%, and the static dryer 90.68%. Concluding that rotary drying has a higher biomass energy consumption and reduces CO2 emissions kg-1 in dry parchment coffee, this method is also preferred by cuppers, as it preserves the sensory qualities of the coffee and contributes to reducing the impact. the environment in the consumption of electrical energy and the reduction of CO2 emissions. However, these predictors need more work to validate reliability.

scholarly journals Influence of sensor and communication setup on electric cam phaser control quality

2018 ◽  
Vol 233 (3) ◽  
pp. 687-696
Author(s):  
Jakob Andert ◽  
Christian Sohn ◽  
Serge Klein ◽  
Andres Tönnesmann ◽  
Jens Oesterdiekhoff ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Control Plant ◽  
Electrical Energy ◽  
Valve Train ◽  
Mechanical Transmission ◽  
Strong Impact ◽  
Control Quality ◽  
Control Units ◽  
The Time Domain ◽  
The Impact

This study investigates the control quality of an electric cam phaser system. The impact of different sensor concepts, synchronization algorithms, controller and hardware topologies on the control quality is examined by using a transient simulation covering the electric cam phaser, valve train, mechanical transmission and a wide variety of cam- and crankshaft trigger wheels. Limited angular accuracy effects are simulated by realistic sensor models and the processing of sensor signals by a real-time capable synchronization algorithm. Nonlinear friction in transmission and valve train are considered by the simulation accordingly. Furthermore, the effects of distributed controller algorithms based on conventional electronic control units are evaluated. Communication latencies have a strong impact on the control plant and are taken into account during controller definition. The effects of different layouts are compared in the time domain, and a sensitivity analysis is carried out to evaluate the effects of different parameters on the cam phasing control quality. The control quality is measured in terms of overshoot, phasing duration and energy consumption of a phasing event. Using a sensor fusion for the current cam phasing angle and an integrated controller layout – that is, an architecture without any communication delay – improves the controllability and reduces overshooting, phasing duration and electrical energy consumption under transient conditions.

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