Validation of plant dynamic model by online and laboratory measurements – a tool to predict online COD loads out of production of mechanical printing papers

COD discharges out of processes have increased in line with elevating brightness demands for mechanical pulp and papers. The share of lignin-like substances in COD discharges is on average 75%. In this thesis, a plant dynamic model was created and validated as a means to predict COD loading and discharges out of a mill. The assays were carried out in one paper mill integrate producing mechanical printing papers. The objective in the modeling of plant dynamics was to predict day averages of COD load and discharges out of mills. This means that online data, like 1) the level of large storage towers of pulp and white water 2) pulp dosages, 3) production rates and 4) internal white water flows and discharges were used to create transients into the balances of solids and white water, referred to as “plant dynamics”. A conversion coefficient was verified between TOC and COD. The conversion coefficient was used for predicting the flows from TOC to COD to the waste water treatment plant. The COD load was modeled with similar uncertainty as in reference TOC sampling. The water balance of waste water treatment was validated by the reference concentration of COD. The difference of COD predictions against references was within the same deviation of TOC-predictions. The modeled yield losses and retention values of TOC in pulping and bleaching processes and the modeled fixing of colloidal TOC to solids between the pulping plant and the aeration basin in the waste water treatment plant were similar to references presented in literature. The valid water balances of the waste water treatment plant and the reduction model of lignin-like substances produced a valid prediction of COD discharges out of the mill. A 30% increase in the release of lignin-like substances in the form of production problems was observed in pulping and bleaching processes. The same increase was observed in COD discharges out of waste water treatment. In the prediction of annual COD discharge, it was noticed that the reduction of lignin has a wide deviation from year to year and from one mill to another. This made it difficult to compare the parameters of COD discharges validated in plant dynamic simulation with another mill producing mechanical printing papers. However, a trend of moving from unbleached towards high-brightness TMP in COD discharges was valid.

Kumpulan tiedekirjaston maantieteen monografiat

Maantieteen lainattavien monografioiden kokoelma sisältää 7288 (7.8.2007) nidettä. Kokoelma on luokiteltu UDK-luokituksen mukaisesti. Asiasanoituksessa on käytetty YSA:n asiasanoja sekä tarpeen vaatiessa vapaita asiasanoja. Kopioinnissa tulleita asiasanoja ei ole poistettu, vaan ne ovat käytössä (esim. Kongressin asiasanat). Monografiat ovat pääosin englannin-, suomen, saksan- ja ruotsinkielisiä. Kirjat ovat vapaasti käytettävissä ja lainattavissa. Laina-aika on 28 vuorokautta. Kokoelman kehittäjien tavoitteena on aina ollut korkeatasoinen maantieteen tieteellinen kokoelma, joka vastaa ainelaitoksen tutkijoiden, opettajien ja opiskelijoiden tarpeita. Laitoksen johto on pitänyt tärkeänä riittävää budjetointia hankinnan tarpeisiin. Hankintapäätökset on tehnyt tieteenalan asiantuntija, yleensä laitoksen johtaja yhteistyössä kirjaston kanssa. Käyttäjät ovat pääsääntöisesti olleet omalta ainelaitokselta, mutta tieteenalan luonteen vuoksi kokoelman käyttäjiä ovat myös lukuisten lähitieteiden tutkijat ja muut yksityishenkilöt. Maantieteen kokoelma sisältää myös laajan aluesuunnittelun kokoelman.

De lingvis igneis, qvam Christi redemtoris auxilio nixus

Invocatio: [Alpha et Omega].

De vestalibvs Romanorvm

Invocatio: Divina adfulgente gratia.

De gemino Messia

Invocatio: [hepreaa].

De caussis ventorum

Invocatio: D.D.

Schedion zoologicum de ira

Invocatio: Divina adfulgente gratia. Ded.: Gustavus Adolphus Humble, Olavus Osander, Andreas Eckerstedt, Peturs Kexerus, Andreas Ståhl, Sveno Fovelin, Samuel Lyseen, Henricus Bereen, Zacharias Tobiis, Lars Eckman [ruots. runo].

De responso Elisaei, 2. Regum VIII: v. 10

Invocatio: Q.F.F.Q.S.

Vaticinium Nahumi latine et fennice

Arkit: E4 F2.

De natura salium simplicium

Dedicatio: Daniel Lithander.

An vitiosae rei detur praescriptio?

Invocatio: I.N.J.C.

De Holmgardia

Invocatio: D.D.

[Melakhim Jehuda]

Invocatio: [hepreaa].