Projekt J1-3029

Naslov in šifra projekta / GA no.

Raziskava medsebojno povezanih procesov za trajnostno ravnanje s komunalnim blatom z namenom njegove snovne predelave in recikliranja / L7-3185

Investigation of interconnected processes for sustainable management of sewage sludge for the purpose of its material recovery and recycling / L7-3185

Partnerji projekta in njihovi logotipi

Vodja projekta: dr. Primož Oprčkal, univ. dipl. inž. geol.

Vodja projekta na ZAG: dr. Primož Oprčkal, univ. dipl. inž. geol.

Trajanje projekta: tri leta (1. 10. 2021 – 30. 9. 2024)

Višina financiranja:

ARRS: 300.000,00 € (75 % delež)

2344 ur cenovne kategorije C letno

Sofinancer: Stonex, geotehnologija, d.o.o. 100.000,00 €, brez DDV (25 % delež)

Povzetek projekta SI:

Čiščenje odpadne vode temelji na uporabi čistilnih naprav (ČN), kjer pri tem nastajajo velike količine komunalnega blata. Na posamezno populacijsko enoto ČN nastane od 15 do 60 g suhe snovi blata dnevno. V Sloveniji letno nastane približno 38 000 ton suhe snovi blata v celotni EU pa kar 10 milijonov ton suhe snovi blata, kar predstavlja velik okoljski in družbeno-ekonomski problem. Zaradi nestabilne sestave, saj ne zagotavlja mehanske trdnosti, mikrobiološke razgradnje in tvorbe metana, blata ni dovoljeno odlagati na odlagališčih odpadkov. Zaradi prevelike vsebnosti potencialno nevarnih snovi (kovin, organskih spojin, mikroplastike, etc.) ga brez obdelave ni mogoče vnašati na kmetijske površine. Zaradi visoke vsebnosti vlage in mineralnih snovi ima skoraj ničelno kurilno vrednost, zato je sežig ali kurjenje blata tehnološko, finančno in izvedbeno zahtevno, hkrati pa povzroča emisije toplogrednih plinov in potencialno nevarnih snovi. Na drugi strani pa se v EU, s sežigom približno 1 milijona ton ali odlaganjem 0,5 milijona ton blata letno, izgubljajo kritične surovine, na primer fosfor ali organska hranila, ki bi jih potrebovali za bogatenje osiromašenih tal. Situacija glede ravnanja z blatom v Sloveniji se je v zadnjih letih zaostrila zaradi prepovedi uvoza s strani Madžarske in zaradi prenehanja sprejemanja s strani sežigalnic, ki so postale prepolne kvalitetnega trdega goriva iz plastike (po prevodi uvoza plastike s strani Kitajske). Zato je strošek ravnanja narasel za več kot trikrat. Za reševanje problematike komunalnega blata je potreben razvoj novih trajnostnih rešitev znotraj okvirov snovnega recikliranja, selektivnega izločanja in izrabe posameznih zanimivih sestavin tega odpadka, v skladu s smernicami Akcijskega načrta EU za krožno ekonomijo kot tudi novega Zelenega dogovora. Postopki recikliranja blata morajo zato v prvi vrsti omogočati predelavo čim večjih količin na ekonomsko sprejemljiv in trajnosten način s čim manjšimi emisijami nevarnih snovi in toplogrednih plinov, pridobljeni proizvodi pa morajo biti okoljsko sprejemljivi in ustrezati tehničnim standardom in smernicam določenega načina rabe. Gradbeništvo predstavlja pomemben segment na področju recikliranja blata z vidika porabe velikih količin materiala, še posebno na področju zemeljskih del. Zato bo v okviru projekta v najširši obliki preučena prav možnost predelava blata v po meri načrtovane in izdelane gradbene kompozite, predvidene za uporabo v zemeljskih delih.
Glavni cilj projekta je razvoj medsebojno povezanih procesov, ki omogočajo celostno obravnavo in trajnostno ravnanje z blatom iz čiščenja komunalne odpadne vode, z namenom njegove snovne predelave in recikliranja v materiale, ki se uporabljajo v gradbeništvu.
Posebni cilji projekta pa so naslednji:

  • Ugotoviti razlike in trende v sezonskih variacijah v sestavi in lastnostih blata iz različnih ČN.
  • Proučiti učinkovitost procesa biomineralizacije blata za pridobivanja humusnega materiala za uporabo v gradbeništvu.
  • Preučiti postopek ekstrakcije hranil (N-P-K) in potencialno nevarnih snovi z mikrobiološkim izluževanjem.
  • Preučiti postopek pirolize blata z namenom pridobivanja energije in biooglja.
  • Razviti recepture in postopke za predelavo blata za proizvodnjo okoljsko sprejemljivih gradbenih kompozitih.
  • Proučiti in določiti možnosti uporabe, določiti smernice za preverjanje lastnosti in kvalitete, in določiti okoljske lastnosti gradbenih kompozitov iz blata.
  • Določiti okoljske vplive preučevanih tehnologij preko analize življenjskega cikla in stroškovnega cikla materialov v okviru primerjalne LCA in LCCA analize.

Povzetek projekta EN:

Povzetek projekta EN: Wastewater treatment is based on the use of treatment plants (WWTPs), where large amounts of sewage sludge are generated. 15 to 60 g of dry matter of sludge per day is produced per individual population unit of WWTP. In Slovenia, approximately 38,000 tons of sludge dry matter is generated annually, and in the entire EU as much as 10 million tons of sludge dry matter, which is a large environmental and socio-economic problem. Due to the unstable composition, as it does not provide mechanical strength, microbiological degradation and methane formation, sludge is not allowed to be landfilled. Due to the excessive content of potentially dangerous substances (metals, organic compounds, microplastics, etc.), it cannot be applied in agriculture without treatment. Due to high content of moisture and minerals, it has almost zero calorific value, so incineration of sludge is technologically, financially and operationally demanding, while causing emissions of greenhouse gases and potentially dangerous substances. On the other hand, in EU, by burning around 1 million tonnes or disposing of 0.5 million tonnes of sludge per year, critical raw materials, such as P or organic nutrients, that would be needed to enrich depleted soils, are lost. Situation regarding sludge management in Slovenia has worsened in recent years due to the import ban from Hungary and the cessation of acceptance by incinerators, which have become overflowing with quality solid fuel (after China plastic imports ban). As a result, cost of handling has more than tripled. To solve the problem of municipal sludge, it is necessary to develop new sustainable solutions within the framework of material recovery, selective extraction and utilization of individual interesting components of this waste, in accordance with guidelines of the EU Action Plan for Circular Economy and the new Green Deal. Sludge recycling processes must primarily enable processing of as many quantities as possible in an economically acceptable and sustainable way with lowest possible emissions of hazardous substances and greenhouse gases, and the products obtained must be environmentally friendly and comply with technical standards. Construction sector represents an important segment in the field of sludge recycling in terms of consumption of large quantities of material, especially in the field of earthworks. Therefore, the project will study in the broadest form the possibility of processing sludge into custom-designed and manufactured building composites intended for use in earthworks.
The main goal of the project is to develop interconnected processes that enable sustainable management of sludge from WWTPs, with the aim of its material processing and recycling into materials used in construction.
The specific objectives of the project are the following:

  • Identify differences and trends in seasonal variations in the composition and properties of sludge from different WWTPs.
  • To study the efficiency of the sludge bio-mineralization process for the production of humus material for use in construction.
  • Examine the process of extraction of nutrients (N-P-K) and potentially hazardous substances by microbiological leaching.
  • To study the process of pyrolysis of sludge in order to obtain energy and biochar.
  • Develop recipes and procedures for sludge processing for the production of environmentally friendly composite construction.
  • To study and determine the possibilities of use, to determine the guidelines for checking the properties and quality, and to determine the environmental properties of mud construction composites.
  • To determine the environmental impacts of the studied technologies through the analysis of the life cycle and cost cycle of materials in the framework of comparative LCA and LCCA analysis.

Faze projekta in opis realizacije (delovni sklopi) (SI in EN)

Delo v okviru projekta bo potekalo v okviru devetih delovnih sklopov (DS), ki so podrobneje opisani v nadaljevanju.
Glavni cilj DS 1 je usklajevanje dela partnerjev in upravljanje raziskovalnega projekta katerega cilj je uspešna in pravočasna izvedba projekta.
V drugem delovnem sklopu (DS 2), ki bo potekal v prvem letu izvajanja projekta, bo izvedeno zbiranje arhivskih podatkov preteklih kemijskih analiz, vzorčenje in detajlna karakterizacija vzorcev blata, ki bodo predstavljali osnovo za nadaljnje eksperimentalno delo. Določitev osnovne sestave blata bo namreč ključna za nadaljnje na optimizaciji procesov predelave, ki morajo zagotavljati učinkovitost recikliranja tudi v primeru najvišjih koncentracij onesnažil. Na podlagi rezultatov raziskav iz tega DS bodo izbrani vzorci blata za nadaljnje raziskave po projektu.
V DS 3 bo delo potekalo na nivoju raziskav z uporabo manjše pilotne simulacije izboljšanega procesa biomineralizacije na trstični gredi, ki bo potekal v kombinaciji s procesom bioizluževanja potencialno nevarnih snovi z uporabo avtotrofnih bakterij.
V okviru tega DS 4 bodo izveden raziskave za laboratorijski razvoj in optimizacijo procesa bioizluževanja N-P-K in organskih snovi iz blata in potencialno nevarnih snovi iz oglja iz pirolize blata z uporabo avtotrofnih in heterotrofnih bakterij.
Raziskave sušenja in pirolize komunalnega blata bodo izveden v okviru DS 5. Z optimizacijo procesa pirolize bo mogoče izdelati pirolitsko oglje z izboljšanimi adsorpcijskimi lastnostmi za predvidene namene rabe v projektu (dodatek biomineraliziranemu blatu), adsorbent za čiščenje blatnenice iz biomineralizacije, dodatek za pripravo gradbenih kompozitov.
V okviru DS 6 bodo potekale raziskave procesov predelave blata v gradbene materiale – geotehnične kompozite. V prvi fazi raziskovalnega dela bodo izbrani primerni aditivi, ki so po svojem izvoru reciklirani industrijski odpadki: kalcijski leteči pepeli (iz sežiga premoga, biomase, ostankov papirniške industrije), odpadna celuloza papirniške industrije, oglje iz pirolize, etc. V drugi fazi bodo pripravljene poskusne recepture za pripravo gradbenih kompozitov z uporabo vzorcev blata iz izbranih. V tretji fazi bodo izvedene raziskave na vzorcih kompozitov iz poskusnih receptur za namen določitve mehanske stabilnosti, okoljske sprejemljivosti in študija imobilizacijskih mehanizmov.
V DS 7 bodo na podlagi rezultatov predhodnega delovnega sklopa izveden podrobnejše geomehanske preiskave, ki bodo potekale v več fazah od začetka pa vse do konca projekta, pri čemer bodo kot osnova za raziskave izbrane recepture kompozitov, ki se bodo v DS 6 izkazale za najbolj perspektivne. Ovrednotena bo tudi veljavnost in zanesljivost postopkov standardnih geomehanskih preiskav, razvitih za zemljine, za preiskovanje novega kompozita iz blata. Proučene bodo morebitne omejitve uveljavljenih postopkov preiskav in podani bodo predlogi prilagoditev. Na podlagi rezultatov analiz in pridobljenih znanj bodo predlagane možnosti rabe kompozitov iz blata.
Ovrednotenje in kvantifikacija okoljskega vpliva procesov bioizluževanja, biomineralizacije, pirolize in pridobivanja kompozitov iz blata bo v okviru DS 8 izvedeno s pomočjo modeliranja ocene življenjskega cikla (LCA) kot je navedeno v direktivi Ecodesign (2009/125/EC).
Zadnji delovni sklop (DS 9) je namenjen diseminaciji in gospodarskemu izkoriščanju rezultatov projekta.

The work of the project will be performed within the scope of nine work packages (WPs), which are described in more detail below.
The main goal of WP 1 is to coordinate the work of partners and manage a research project whose goal is the successful and timely implementation of the project.
The second work package (WP 2), which will take place in the first year of the project, will collect archival data from past chemical analyses, sampling and detailed characterization of sludge samples, which will form the basis for further experimental work. The determination of the basic composition of sludge will be crucial for further optimization of processing processes, which must ensure the efficiency of recycling even in the case of the highest concentrations of pollutants. Based on the research results from this WP, sludge samples will be selected for further research after the project.
In WP 3, the work will be carried out at the research level using a small pilot simulation of an improved reed beds biomineralization process, which will be carried out in combination with the process of bioextraction of potentially hazardous substances using autotrophic bacteria.
Under the WP 4, research will be carried out for laboratory development and optimization of the process of bioextraction of N-P-K and organic substances from sludge and potentially dangerous substances from coal from sludge pyrolysis using autotrophic and heterotrophic bacteria.
Research on drying and pyrolysis of sewage sludge will be carried out under WP 5. By optimizing the pyrolysis process, it will be possible to produce pyrolytic charcoal with improved adsorption properties for the intended uses in the project (addition to biomineralized sludge).
Within WP 6, research will be carried out on the processes of sludge processing into building materials – geotechnical composites. In the first phase of the research work, suitable additives will be selected, which are recycled industrial waste by their origin: calcareous ash (from coal incineration, biomass, waste paper residues), waste pulp from the paper industry, pyrolysis coal, etc. In the second phase, experimental recipes for the preparation of building composites will be prepared using mud samples from the selected ones. In the third phase, research will be carried out on samples of composites from experimental recipes for the purpose of determining mechanical stability, environmental acceptability and the study of immobilization mechanisms.
Based on the results of the previous work package, more detailed geotechnical investigations will be carried out in WP 7, which will take place in several phases from the beginning to the end of the project. The validity and reliability of standard geomechanical testing procedures developed for soils for testing a new sludge composite will also be evaluated. Possible limitations to established investigation procedures will be examined and proposals for adjustments will be made. Based on the results of analyses and acquired knowledge, the possibilities of using sludge composites will be proposed.
Evaluation and quantification of the environmental impact of bioleaching, biomineralization, pyrolysis and sludge extraction processes under WP 8 will be carried out using life cycle assessment (LCA) modelling as specified in the Ecodesign Directive (2009/125 / EC).
The last work package (WP 9) is dedicated to the dissemination and economic exploitation of project results.

Logotip financerja

STONEX, geotehnologija, d.o.o.