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Radziszewski P.,Metso | Moore A.,Metso
Minerals Engineering | Year: 2017

Since about the late-1970s, stirred mills have entered into use in the mineral processing industry. Much work has focused on model developed for power, grinding and performance prediction. However, little effort is cited in the literature related to wear and particularly impeller wear. In this paper, the focus will be on examining how two pressure profile models might affect stirred mill impeller wear profiles specifically in the gravity induced stirred mill case. The investigation will start with a re-visit of a mechanistic impeller wear model for stirred mills which includes some indications on how impeller wear affects mill power. Subsequently a review of a few pressure profile models analysis will lead to exploring the effect of the pressure profile on impeller wear. The paper will close with a discussion on how the model could be used to illustrate the effect of wear on any impellor design. © 2016

Arpomaa and Metso | Date: 2014-06-18

An apparatus and method for adjusting air pressure of a room. The apparatus comprises an air receive duct (4) arranged to receive air from the room (2), an air distribution casing (5) connected to the receive duct (4), first and second air vents (6, 7) connected to the air distribution casing (5) and arranged to convey air coming from the receive duct (4) out of the apparatus (1), and a control means (8) arranged to adjust the flow resistance of the second air vent (7) in relation to that of the first air vent (6).

Goldman J.,Metso
2013 PEERS Conference, Co-located with the 2013 International Bioenergy and Bioproducts Conference | Year: 2013

Moisture is one of the most measured characteristics in the raw materials used across our industry. Many different technologies have been utilized for measuring moisture content of many of these materials. Conventional oven drying has been the standard for many of these materials. However, this method requires resources and significant time to provide results. There is now a fast and efficient measurement available for moisture content of almost any material containing water. The newly available magnetic resonance moisture measurement method is different than any of the existing methods that are already in use. This new measurement technology actually measures water content by measuring the hydrogen atoms from the free water molecules present in the batch sample. The technology used is based on the same scientific phenomenon as Magnetic Resonance Imaging (MRI) commonly used in the medical field. The MRI method has been simplified from the MRI devices for efficient use in industrial applications. The water content is analyzed through the magnetic resonance (MR) signal induced by hydrogen atoms in water molecules placed in magnetic fields. This paper seeks to explain how this measurement works and show where it can be applied in today's woodyard, pulp mill, or biofuel boiler. This new measurement can be used to measure the moisture level of virtually any sample containing water from wood chips down to mineral slurries. Although this technology was developed mainly for the rapidly growing biofuel industry, it is also capable of measuring almost any bulky material that does not contain ferromagnetic ingredients. Feasible industry applications are pulping and some specific minerals. Suitable materials include wood based samples such as wood chips, forest residue chips, and peat. This method can also be used to measure the moisture content of annual fibers such as straw, grains, or willow grass. In addition to these applications the measurement can also be applied to minerals, foodstuffs, and sludges. This method has been shown to challenge the accuracy level of the conventional oven drying method. Also, the analysis is much faster than the oven drying method. This analysis takes somewhere between 30 seconds to 2 minutes, depending on the moisture content and the makeup of the sample. The accuracy has been proven to be +/- 1% on samples with moisture levels anywhere from 10% to 90%. Copyright © 2013 by the TAPPI Press. All rights reserved.

Lampela K.,Metso
2013 PEERS Conference, Co-located with the 2013 International Bioenergy and Bioproducts Conference | Year: 2013

In modern pulp mills, the automation has an essential role in ensuring economical production and, at the same time, high quality and uninterrupted production. This paper discusses optimizing a batch and continuous cooking process based on alkali measurements and controls as well as Kappa and residual alkali measurement-based feedback controls. New developments in pulp cooking - such as several alkali addition points and circulations - complicate process control and they also mean new challenges for the measurement of pulp properties. The goal is to find and maintain optimum cooking conditions throughout the digester to ensure selective delignification and to simultaneously optimize pulp quality and production costs. To achieve this, we need reliable pulp quality measurements that provide accurate real-time information. In fact, without proper automation and measurements, it will become impossible to achieve payback for these quite high capital investments. Cooking is a highly interactive process and practically all of the major control loops are coupled. At the same time, there are a lot of different disturbances present - wood age, density, chip size, white liquor concentration, etc (Figure 1). The new development in the digester area together with measurements and controls makes it possible to control and optimize the temperature and alkali profile. In this paper, we introduce a technology that goes even further. By measuring the alkali profile in cooking and comparing the actual measured profile to a 'reference' profile, we can make conclusions about what is the original disturbance source (wood age, chip size, etc.) and make the right corrective actions based on that. This paper will reviews multiple mill case studies about cooking automation projects with documented results. Copyright © 2013 by the TAPPI Press. All rights reserved.

Jaatinen E.,Metso
Paper Conference and Trade Show 2011, PaperCon 2011 | Year: 2011

The capabilities of an on-line condition monitoring system have been embedded in a distributed control system (DCS) which uses common I/O hardware, signal processing hardware and software, engineering configuration tools, information trending and alarming. Machine operators and a maintenance staff are now able to see quickly developing vibration and process pulsation problems and determine their causes, using a unified user interface which is combined with process control functions of the DCS. With this facility, operators are alerted quickly to developing problems so effective corrective action can be initiated. This operator-initiated maintenance combined with regular monitoring of machinery condition by maintenance staff promotes a cooperative effort which improves machinery uptime and leads to cost-effective maintenance planning.

Postnikov V.,METSO
17th ITS World Congress | Year: 2010

The presented concept of Global Intelligent Transportation System (GITS) consists of two subsystems: Ground and Sea. An element of both subsystems is an unmanned Automated Vehicle (AV) that may be considered as a hybrid of conventional motor vehicle and rail electric vehicle. It is possible to say that it is a high speed truck or trolleybus. GITS is not a breakthrough but it is an evolutionary step relating to Railroad systems that are nearly 200 years old and to Motor Vehicle systems that are nearly 100 years old. Using the achievements of contemporary control and communication systems there is a good chance to make an automatic transportation system today that may be economically effective, environmentally friendly and safe. It is possible to say that GITS is a concept of Transport Internet.

Nuyan S.,Metso
Paper Conference and Trade Show, PaperCon 2014 | Year: 2014

The replacement of a twenty-year-old quality control system (QCS) on an off-machine coater has solved a mill's servicing problems and improved the coating application control performance considerably, meeting the customer's performance guarantees and providing an expected return on investment. New, variable-speed adaptive scanning features have reduced startup waste considerably and have improved the CD profiles. The online diagnostic tools of the new system are valuable operator aids that are used to detect and correct quality variation problems and coating flaws. The fixed point trending feature of the system is used regularly. The system's high-resolution measurement capabilities have been used by the operators to detect and solve coating streaks on the jet coating stations.

Klerelid I.,Metso
Paper Technology | Year: 2013

The Advantage™ NTT™ is a machine concept and process that combines low energy cost and premium tissue quality. The NTT machine is flexible in respect of tissue products, as it can operate in two modes and it only requires a belt change to switch properties between textured and plain. The press section consists of two fabric loops, such as the felt loop and the NTT belt loop. The felt loop is very similar to a DCT machine with the exception of a vacuum dewatering roll before the NTT shoe press nip. Dewatering of the felt and web over the vacuum turning roll is important for the dryness achieved in the press section. A curved is located over the vacuum roll steam box, which heats the web and improves press performance. Showering and conditioning of the felt is the same as in a DCT machine, while the two UhIe boxes are conveniently placed on the floor.

Swietlik F.,Metso
Paper Conference and Trade Show 2010, PaperCon 2010 | Year: 2010

• Modern closed draw press section offers • reliable configurations for a wide speed range • effective dewatering at desired quality level • good, stable runnability • potential for speeds well above 2000 m/min • New solutions for building a press section • no cantilevering beams or anchoring • modularity for faster installation • easier operation and maintenance.

Fu C.,Metso | Nuyan S.,Metso
Paper Conference and Trade Show, PaperCon 2014 | Year: 2014

A new modeling method is developed to estimate an accurate CD fiber orientation response to slice position changes. The adaptive response model is the key factor in the optimization of CD fiber orientation angle and along with a feed-forward compensation technique enables robust control of fiber orientation profile. The adaptation takes into account several key process operating conditions such as the speed of the paper machine, jet-to-wire ratio and headbox slice opening. It uses an optimization algorithm to first fit an "STFI weight response" model to bump-test data and then calculates a parameterized family of fiber orientation responses which can be adapted for different operating points. The use of feed-forward compensation increases the agility of the system in the presence of head-box side flow disturbances. An additional feature implemented in a CD controller for the first time is the ability to "de-convolute" a CD response from the bump test results of multiple actuator moves. This technique is quite useful and sometime essential when it is difficult to deduce the CD response from a single-actuator move or when a better CD response model is desired. The paper describes the new modeling features and presents experiences and results from two different board machines.

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