Projekt J1-4413

Partnerji projekta in njihovi logotipi

Vodja projekta:
Vesna Zalar Serjun

Vodja projekta na ZAG:
Vesna Zalar Serjun

Link na projektno skupino

Link na SICRIS

Trajanje projekta: 01. 10. 2022 – 30. 09. 2025

Višina financiranja:
ARRS: 2667 letnih ur cenovnega razreda B

Povzetek projekta SI:

Elektrofiltrski pepeli, pepeli z rešetk in ciklonski prahovi predstavljajo ostanke čiščenja plinov v visokotemperaturnih procesih v industriji in energetiki. S postopnim zmanjševanjem rabe fosilnih goriv (strategija Celovitega nacionalnega energetskega in podnebnega načrta) se količina nastalega pepela pri kurjenju premoga sicer zmanjšuje, povečuje pa se količina mešanih pepelov in pepelov iz sežiga biomase. Gradbeništvo predstavlja potencialno pomemben segment na področju recikliranja pepelov z vidika njihovih lastnosti in porabe velikih količin materiala, še posebno na področju zemeljskih del. Med drugim se tako določeni tipi pepelov reciklirajo kot učinkovito sredstvo za imobilizacijo težkih kovin, ki istočasno tudi izboljšajo geotehnične lastnosti remediiranih materialov, saj imajo funkcijo alternativnega veziva.

Ker imajo številni pepeli visoko uporabno vrednost, po drugi strani pa pepeli predstavljajo ene od bolj kompleksnih antropogenih materialov, je potreba po detajlni karakterizaciji vsakega posameznega pepela pred uporabo nujna. Za oceno potenciala recikliranja pepelov je potrebno poleg mikrostrukture, mineraloške in kemijske sestave ter vpliva na okolje, natančno opredeliti tudi njihovo hidravlično reaktivnost. Pomembna karakteristika večine pepelov je, da predstavljajo (latentno) hidravlični material, ki ga v glavnem predstavlja steklasta faza v njihovi kompleksni sestavi. Dokazano je, da reaktivnosti pepelov ni možno določiti samo na podlagi njihove celokupne kemijske in fazne sestave. Analize pepelov z zelo podobno kemijsko in mineralno sestavo so namreč pokazale velike razlike v lastnostih/obnašanju kompozitov, v katerih so bili vgrajeni. Reaktivnost pepelov je odvisna predvsem od karakteristik steklaste faze.

Cilj predlaganega projekta je detajlno okarakterizirati pepele iz različnih termičnih procesov. Enega izmed ključnih sklopov tega projekta predstavlja detajlna karakterizacija steklaste faze pepelov, ki predstavlja glavno komponento večine pepelov. Dejstvo je, da za korelacijo med hidravlično aktivnostjo pepelov, njihovo celokupno sestavo in fizikalnimi lastnostmi ter tipom steklaste faze primanjkuje eksperimentalnih dokazov. Na podlagi detajlne analize pepelov bomo raziskali potenciale za zvišanje stopnje reaktivnosti (aktivacija) tistih pepelov z nižjo stopnjo reaktivnost (in tistih ki so tretirani kot nereaktivni) v dvokomponentnem sistemu z uporabo dodatnega recikliranega materiala. Na fenomenološki ravni bi z izvedbo projekta definirali potek hidratacije raziskovanih pepelov z dvema različnima količinama vode in poiskali korelacije s stopnjo hidratacije, vrstami hidratacijskih produktov, tipom steklaste faze in mehansko‐ fizikalnimi lastnostmi kompozitov iz pepelov.

Predlagane metode dela zajemajo širok nabor naprednih komplementarnih analitskih metod, hkrati pa vključujejo raziskave predpisane s standardi. Z izvedbo projekta bi povečali stopnjo recikliranja in uporabno vrednost pepelom in pomembno prispevali k trajnostni rabi naravnih virov in razvojem nizkoogljične in krožne ekonomije. Pridobljeno znanje bi omogočilo izdelavo gradbenih kompozitov, narejenih ciljno (in ne zgolj na podlagi empiričnih podatkov) po meri predvidene uporabe v zemeljskih delih.

Povzetek projekta EN:

Fly ashes, bottom ashes, cyclone, and bag filter ashes represent the by‐products generated by the air pollution control equipment in high‐temperature processes in industry and energetics. With the gradual reduction of the use of fossil fuels (Integrated National Energy and Climate Plan paradigm), the quantities of ash generated during coal combustion decreases, while the quantities of ashes from co‐combustion and ashes from biomass combustion increases. The ideal sector for the recycling of the ash is the construction industry. In the construction sector two synergetic effects are achievable: large amounts of material can be consumed and, at the same time, in the case of earthworks (bonded composites) the harmful elements can be permanently immobilized through the immobilization process. Specific types of ashes can be successfully recycled by their usage as an efficient immobilization additive of potentially toxic elements which parallel also enhance the geotechnical characteristics of remediated materials to be used for earthworks.

Since different ashes possess a high usable value, and on the other hand, ashes represent one of the more complex anthropogenic materials, the need for a detailed characterization of each individual ash before use is essential. To assess the recycling potential of ash, in addition to microstructure, mineral and chemical composition, and environmental impact, it is necessary to precisely define their hydraulic reactivity An important characteristic of most of the ashes is that they possess (latent) hydraulic characteristics, which mainly accounts for the glassy phase in their complex composition. It has been shown that the reactivity of ashes cannot be determined solely on the basis of their overall chemical and phase composition. Analyses of ashes with a very similar chemical and mineral composition showed large differences in the properties/behaviour of the composites in which they were incorporated. The reactivity of the ashes depends mainly on the characteristics of the glassy phase.

The aim of the proposed project is to characterize in detail the ashes from various thermal processes. One of the key parts of this project is the detailed characterization of the glassy phase of the ashes which represent the major component of the ashes. However, there is a lack of experimental evidence, which could directly link the hydraulic activity of ashes, their bulk composition and physical properties to the characteristics (type) of amorphous phase. On the basis of detailed characterization of ashes, the potential for increasing the reactivity (activation) of ashes with lower reactivity (and those identified as non‐reactive) in a two‐component system, using an additional recycled material will be investigated.

The realization of the proposed research work would enable to define the fundamentals based on which the hydration process of the investigated ashes at two different amounts of water addition would be defined and correlations between the level of hydration, types of hydration products, type of amorphous phase and mechanical and physical properties of ashes composites would be explained on the phenomenological level.

The methodology will be based on broad range of advanced complementary methods, including the analysis prescribed in relevant standards. Research work described in the project would promote the recycling rate and the added value of ashes, which would have a significantly positive impact on the sustainable use of natural resources, the reduction of the carbon footprint and the development of circular economy. Gained knowledge would enable the prediction of (long‐term) characteristics of ash composites, which would not be based solely on the use of empirically determined amounts of ash needed on a case‐by‐case basis but on the carefully tailored mixing of various residues.

Faze projekta in opis realizacije (delovni sklopi)

Podrobno je definiranih 6 opisov tveganj, vključno s predlaganimi ukrepi za njihovo blažitev.

Bibliografske reference:

Link na Bibliografsko referenco