| | SLO | ENG | Cookies and privacy

Bigger font | Smaller font

Show document Help

Title:OPTIMIZACIJA IN MODELIRANJE ODSTRANJEVANJA ŽIVEGA SREBRA IZ DIMNIH PLINOV
Authors:ID Hosnar, Jernej (Author)
ID Novak-Pintarič, Zorka (Mentor) More about this mentor... New window
ID Goršek, Andreja (Comentor)
ID Horvat, Milena (Comentor)
Files:.pdf UNI_Hosnar_Jernej_2011.pdf (2,98 MB)
MD5: 7945DAE765BCE4EE3F6B56A52570F96E
PID: 20.500.12556/dkum/0d729f83-7b7c-474e-84d8-b83b27cdc29c
 
Language:Slovenian
Work type:Undergraduate thesis
Organization:FKKT - Faculty of Chemistry and Chemical Engineering
Abstract:Približno 46 % vseh svetovnih emisij Hg je posledica izgorevanja fosilnih goriv v namene pridobivanja električne in toplotne energije. Zaradi visokih koncentracij onesnaževala v dimnih plinih si strokovnjaki prizadevajo razviti ustrezno tehnologijo, ki bi omejila izpuste Hg že na viru. Tako bi se izognili problematiki povečanega biogeokemijskega kroženja Hg, ki predstavlja prehod iz fosilnih goriv v zrak, vodo, tla in se akumulira v živih organizmih. Na podlagi podatkov o kemijskem ravnotežju in kinetiki smo razvili enostaven matematično-kemijski model, kot začetno stopnjo, za preverjanje realnega obnašanja prisotnih ionov v raztopini pri razžveplanju dimnih plinov (RDP). Z demonstracijo uporabe modela smo ocenili stopnjo odstranitve Hg iz naprave ter dimenzionirali velikost potrebne opreme pri razvoju sodobne tehnologije. Čiščenje emisij sicer poteka po dveh principih, ki smo jih preučili v laboratoriju ter s pomočjo literature. Prva rešitev je temeljila na odstranitvi elementarnega Hg iz dimnih plinov v mokrem postopku RDP sistema z oksidacijo, kjer se konstantno ruši ravnotežje, ki ga opisuje Henry-ev zakon. Oksidacijo smo izvedli z vrsto oksidantov - tudi s kisikom, ki se uvaja v vodno fazo z dispergiranjem zraka. Na spontanost reakcij oksidacije so kazale negativne Gibbs-ove entalpije. Druga možnost je temeljila na odstranitvi večjega števila onesnaževal v postopku RDP, ki je ekonomsko in tehnološko primerljiv ali boljši od postopkov, ki so komercialno že uveljavljeni ali v fazi razvoja. Preučili smo objavljene tehnologije na principu: homogene oksidacije s halogenidi (Br2, Cl2) pred razžveplanjem dimnih plinov, adsorpcije na aktivnem oglju ter dodajanja kemijskih oksidantov, kot sta NaClO2 in H2O2, v mešalni pretočni reaktor za pospešitev katalizirane reakcije. Alternativne tehnologije smo ocenili na podlagi porabe materialov, energentov, dela ter obratovalnih stroškov. Ekonomske parametre smo uporabili v ekonomskem kriteriju, ki omogoča izbiro tržno najustreznejše tehnologije ter pregledom okoljskih kriterijev, ki podajajo sugestijo za izbiro okoljsko najustreznejšega načina odstranjevanja Hg.
Keywords:elementarno živo srebro, homogena oksidacija živega srebra, proces razžveplanja dimnih plinov, adsorpcija Hg na aktivnem oglju, optimizacija in matematično modeliranje kemijskega sistema
Place of publishing:Maribor
Publisher:[J. Hosnar]
Year of publishing:2011
PID:20.500.12556/DKUM-18392 New window
UDC:669.791.33(043.2)
COBISS.SI-ID:15156758 New window
NUK URN:URN:SI:UM:DK:Y54WUIVV
Publication date in DKUM:18.05.2011
Views:2896
Downloads:219
Metadata:XML DC-XML DC-RDF
Categories:KTFMB - FKKT
:
Copy citation
  
Average score:(0 votes)
Your score:Voting is allowed only for logged in users.
Share:Bookmark and Share



Hover the mouse pointer over a document title to show the abstract or click on the title to get all document metadata.

Secondary language

Language:English
Title:OPTIMIZATION AND MODELING OF MERCURY REMOVAL FROM FLUE GASES
Abstract:Approximately 46 % of all global emissions of Hg result from the combustion of fossil fuels for the purposes of acquiring electricity and heat. Due to high concentrations of pollutants in the flue gases, professionals are striving to develop appropriate technology that would limit the emissions of mercury already in the source. This would avoid the problem of increased biogeochemical cycling of Hg, which represents the transition from fossil fuels into air, water, soil, and accumulates in living organisms. Based on the chemical equilibrium and kinetics, we developed a simple mathematical-chemical model, as an initial step for verifying the real behavior of ions present in solution at flue gas desulphurization (FGD). With the demonstration of the usage of the model we estimated the level of mercury removal from the device and dimensioned the size of the equipment, necessary in the development of modern technology. Cleaning of the emissions is guided by two principles that we have studied in the laboratory and through literature. The first solution is based on the removal of elemental mercury from flue gases in the wet procedure of the FGD system with oxidation, where the equilibrium, described by the Henry’s law, is constantly destroyed. Oxidation was performed by a series of oxidizing agents - even with oxygen, which is being introduced in the aqueous phase by air dispersion. Negative Gibbs's enthalpies, indicated the spontaneity of oxidation reactions. Another possibility is based on the removal of a large number of pollutants in the FGD process, which is economically and technologically comparable to or better than the procedures that are commercially already established or under development. Published technologies have been examined on the principle of: the homogeneous oxidation with halides (Br2, Cl2) before the flue gas desulphurization, the adsorption on activated carbon, and the addition of chemical oxidants such as NaClO2 and H2O2, in the mixing flow reactor to accelerate the catalyzed reaction. Alternative technologies were evaluated on the basis of material consumption, energents, labor and operating costs. Economic parameters were used in the economic criterion, which allows the selection of the market’s most appropriate technology and the review of environmental criteria, which give a suggestion for selecting the environmentally most appropriate method of the disposal of Hg.
Keywords:elemental mercury, homogeneous oxidation of mercury, flue gas desulphurization process, adsorption of Hg on activated carbon, optimization and mathematical modeling of chemical system


Comments

Leave comment

You must log in to leave a comment.

Comments (0)
0 - 0 / 0
 
There are no comments!

Back
Logos of partners University of Maribor University of Ljubljana University of Primorska University of Nova Gorica