haku: @keyword siistaus / yhteensä: 5
viite: 4 / 5
| Tekijä: | Ghiasvand Mohamadkhani, Mohammad |
| Työn nimi: | Application of Electroflotation for Deinking Process |
| Julkaisutyyppi: | Diplomityö |
| Julkaisuvuosi: | 2007 |
| Sivut: | v + 52 s. + liitt. 9 Kieli: eng |
| Koulu/Laitos/Osasto: | Puunjalostustekniikan osasto |
| Oppiaine: | Puunjalostuksen kemia (Puu-19) |
| Valvoja: | Laine, Janne |
| Ohjaaja: | Pirttinen, Esa |
| OEVS: | Sähköinen arkistokappale on luettavissa Aalto Thesis Databasen kautta.
Ohje Digitaalisten opinnäytteiden lukeminen Aalto-yliopiston Harald Herlin -oppimiskeskuksen suljetussa verkossaOppimiskeskuksen suljetussa verkossa voi lukea sellaisia digitaalisia ja digitoituja opinnäytteitä, joille ei ole saatu julkaisulupaa avoimessa verkossa. Oppimiskeskuksen yhteystiedot ja aukioloajat: https://learningcentre.aalto.fi/fi/harald-herlin-oppimiskeskus/ Opinnäytteitä voi lukea Oppimiskeskuksen asiakaskoneilla, joita löytyy kaikista kerroksista.
Kirjautuminen asiakaskoneille
Opinnäytteen avaaminen
Opinnäytteen lukeminen
Opinnäytteen tulostus
|
| Sijainti: | P1 Ark TKK 460 | Arkisto |
| Avainsanat: | deinking electroflotation electrocoagulation brightness ash and mass yields siistaus electroflotaatio electrokoagulaatio vaaleus tuhkan ja massan saanto |
| Tiivistelmä (eng): | Application of electricity for flotation in the water purification processes has been common practice for many years. This master's thesis examines a novel procedure to investigate the application of electroflotation in deinking. To undertake this work, a Voith laboratory flotation cell, combined with various electrocells, was used. The electrocells were Inlet, Al Bottom, Inert and Al Inlet Cells. The electrodes were designed and manufactured by Savcor Group Ltd Oy. Electrocells are able to liberate micro-bubbles from the cathode electrode and dissolve Al ions from the anode electrode. Electrocells were run in two different modes: potentiostate mode (Inlet Cell) and galvanostatic mode (Inert, Al Bottom and Al Inlet Cells). Trials were done in a laboratory and a mill (Stora Enso Sachsen Papir GmbH in Germany based on 100% recycled paper). In the laboratory tests, the same chemicals were applied for all experiments to observe the impact of electrocells, using NaOH 1%, fatty acid soap 1%, sodium silicate, Na2SiO3 (water glass) 2% and calcium chloride, CaCl2 2%. Two sampling points were used for the mill experiments: Inlet Primary Preflotation with 44-48% brightness and Outlet Secondary Postflotation with 60-60.5% brightness. For all trials, handsheets were made. In order to evaluate the results, brightness and yield were measured for the laboratory experiments. For mill experiments, brightness, ash content and yield were measured. The results showed that the brightness increase is strongly affected by the use of electricity in the cells. The brightness gain ranged between 2-4% in some cases. The galvanostatic mode gave better results than the potentiostate mode. It was possible to reach the desired brightness within a short flotation time compared to that in a conventional cell. It seems that dissolved Al ions increased the selectivity of electrocells, removing more ash than fibers. In some cases, final mass was higher than with a conventional cell. This could be explained by less entrapment of fibers by micro-bubbles and high selectivity of the electrocells. It is necessary to find an optimum level for the electricity input. Moreover, in order to evaluate precisely the electroflotation process and to optimize the charge dose related to the operating charge values/flotation time, some supplementary measurements are needed, such as measuring the Al ion concentration and evaluating the number of specks on the handsheets. Generally, application of electroflotation would seem to offer a huge potential for improving the deinking process. More studies, including pilot and mill-scale scales are needed to explore this potential. |
| ED: | 2007-03-13 |
INSSI tietueen numero: 33240
+ lisää koriin
INSSI