In this work, we present the application of solar photocatalysis for air purification including toxic substances such as ammonia and methane normally related to emissions from agriculture (e.g., ...poultry and cattle farms), landfills, etc. The study was done in three different laboratory and semi-pilot scale reactors: annular reactor (AR), mini-photocatalytic wind tunnel (MPWT), and photocatalytic wind tunnel (PWT). Reactors present a physical model for estimation of air-borne pollutant degradation over TiO
2
-based photocatalytic layer in respect to optimal operating conditions (relative humidity, air/gas flow, and feed concentration). All studies were performed under artificial solar irradiation with different portions of UVB and UVA light. The application of solar photocatalysis for air purification was evaluated based on thorough monitoring of pollutants in inlet and outlet streams. The kinetic study resulted with intrinsic reaction rate constants:
k
p,int,NH3
= (3.05 ± 0.04) × 10
−3
cm
4.5
mW
−0.5
g
−1
min
−1
and
k
p,int,CH4
= (1.81 ± 0.02) × 10
−2
cm
4.5
mW
−0.5
g
−1
min
−1
, calculated using axial dispersion model including mass transfer considerations and first-order reaction rate kinetics with photon absorption effects. The results of photocatalytic oxidation of NH
3
and CH
4
confirmed continuous reduction of pollutant content in the air stream due to the oxidation of NH
3
to N
2
and CH
4
to CO and CO
2
, respectively. The application of solar photocatalysis in outdoor air protection is still a pioneering work in the field, and the results obtained in this work represent a good basis for sizing large-scale devices and applying them to prevent further environmental pollution. In the current study, a TiO
2
P25 supported on a glass fiber mesh was prepared from commercially available materials. The system designed in this way is easy to perform, operate, and relatively inexpensive.
In this paper are presented challenges that countries of European Union face when recycling ships and composite boats. European ship owners control over 40 % of the world’s merchant ship fleet, with ...Greece as the top ship-owning country
globally. Nowadays, ship recycling is being regulated and positive progression
was made towards it since steel industry belongs in world’s top five and stable
market and makes recycling of scrap metals from ships attractive. On the other
hand, yachts, sailing boats and small boats are mainly made from composite
materials because of their favourable properties, making them great investment,
but end-of-life management is more complicated and not quite regulated by the
law yet. Unlike commercially oriented ships, which are constantly in move and
disposed when the maintenance costs of the vessel start to exceed possible
revenue, old boats for recreational and tourism-oriented purposes most rarely
move. Hundreds of thousands lie in marinas and are abandoned due to the
maintenance costs thus discouraging the owners from keeping it. Hence, a
growing number of marinas worldwide will have the problem of boat disposal in a
sustainable way in the future. In this paper is given short summary on waste
ships and boats management issues. The emphasis is on waste management of small composite boats
In this work, we present the application of solar photocatalysis for air purification including toxic substances such as ammonia and methane normally related to emissions from agriculture (e.g., ...poultry and cattle farms), landfills, etc. The study was done in three different laboratory and semi-pilot scale reactors: annular reactor (AR), mini-photocatalytic wind tunnel (MPWT), and photocatalytic wind tunnel (PWT). Reactors present a physical model for estimation of air-borne pollutant degradation over TiO
-based photocatalytic layer in respect to optimal operating conditions (relative humidity, air/gas flow, and feed concentration). All studies were performed under artificial solar irradiation with different portions of UVB and UVA light. The application of solar photocatalysis for air purification was evaluated based on thorough monitoring of pollutants in inlet and outlet streams. The kinetic study resulted with intrinsic reaction rate constants: k
= (3.05 ± 0.04) × 10
cm
mW
g
min
and k
= (1.81 ± 0.02) × 10
cm
mW
g
min
, calculated using axial dispersion model including mass transfer considerations and first-order reaction rate kinetics with photon absorption effects. The results of photocatalytic oxidation of NH
and CH
confirmed continuous reduction of pollutant content in the air stream due to the oxidation of NH
to N
and CH
to CO and CO
, respectively. The application of solar photocatalysis in outdoor air protection is still a pioneering work in the field, and the results obtained in this work represent a good basis for sizing large-scale devices and applying them to prevent further environmental pollution. In the current study, a TiO
P25 supported on a glass fiber mesh was prepared from commercially available materials. The system designed in this way is easy to perform, operate, and relatively inexpensive.
The usage of old equipment (over 10-year-old diesel-fuelled waste collection vehicles, WCVs) for municipal solid waste (MSW) collection in Ludbreg for longer than a decade has had a negative ...environmental impact, which has been reduced by replacing an old diesel WCV with a new diesel WCV. This study aims to assess the share of air emissions of two old WCVs (FAP 1990 and MAN 2003) and one new (MAN 2015), expressed in CO2 emissions. In addition, these vehicles have been found easily to reach the limit of 100 dB, which can cause hearing damage in their surroundings. Furthermore, their average fuel consumption is more than 80 l per 100 km, which makes them ineffective in terms of fuel consumption. Generally, higher fuel consumption results in more emissions and for a more eco-friendly operation, the MAN 2003 from Ludbreg WCV fleet should be technically amended and adjusted, and the FAP 1990 should be retired. Although the MAN 2015 is diesel fuelled, the best solution for replacement, according to Maimoun et al. (Waste Management 33: 1079–1089, 2016), would be the use of hydraulic-hybrid vehicles, which provide the best environmental benefits over other alternatives. According to Maimoun et al., hybrid is better environmentally, diesel is the best environmental–economical option and landfill gas-sourced natural gas is the best alternative when accessible because it significantly (up to 80%) reduces emissions of hazardous gases as well as noise levels (50–98%).
Hlapivi organski spojevi (eng. Volatile Organic Compounds, dalje: VOC)i aerosoli postali su jedni od glavnih onečišćivala zraka, u zatvorenim i otvorenim prostorima. Izvor VOC-eva u zraku je i česta ...upotreba herbicida i pesticida općenito zbog visoke hlapivosti takvih organskih molekula, dok se dio pesticida veže na krute čestice i prenosi se zrakom u obliku aerosola. Široka upotreba pesticida na poljoprivrednim površinama doprinosi povećanoj koncentraciji VOC- eva u zraku obzirom da su poljoprivredne površine prepoznate kao kolektivni izvori emisija. Trenutno ne postoji zakonodavna osnova za praćenje emisija s poljoprivrednih površina. Sukladno Objedinjenim uvjetima zaštite okoliša, odnosno IPPC direktivi, fotokatalitička oksidacija uz TiO2navodi se kao alternativna najbolja raspoloživa tehnika (NRT), učinkovita za uklanjanje VOC-eva iz zraka. To je proces koja koristi sinergijsku interakciju svjetlosnog zračenja, katalizatora - poluvodiča i oksidacijskih spojeva kako bi razgradila onečišćivala u fluidima (vodi i zraku) do H2O i CO2 te ostalih inertnih produkata ovisno o kemijskom sastavu onečišćivala.
Kako bi se potvrdila mogućnost primjene fotokatalitičke oksidacije za uklanjanje tragova herbicida iz zraka, proveden je niz eksperimenata u anularnom fotoreaktoru pod utjecajem simuliranog sunčevog zračenja. Rezultati su pokazali da je primjenom navedene tehnologije solarne fotokatalize pri optimalnim uvjetima relativne vlažnosti zraka moguće ukloniti/razgraditi promatrano onečišćivalo i smanjiti udio VOC-eva u struji zraka.
Prema postojećim važećim propisima za eksploataciju mineralnih sirovina potrebna je provedba procjene utjecaja zahvata na okoliš. Pri otvaranju eksploatacijskog polja projektna dokumentacija prema ...važećim propisima mora sadržavati i način sanacije prilikom zatvaranja. Međutim, dosadašnja praksa pokazuje da se sanaciji eksploatacijskih polja pristupa isključivo s tehničke strane koja podrazumijeva rudarske radove radi provedbe mjera osiguranja otkopanih prostora, kojima se isključuje mogućnost nastanka opasnosti za ljude i imovinu, kao i za prirodu i okoliš. Nerijetko se događa da se napuštena eksploatacijska polja ne saniraju, a prenamjena prostora se u sklopu tehničke sanacije niti ne uzima u obzir. Sa stajališta zaštite okoliša, iskorištavanje mineralnih sirovina ima daleko najveći negativni utjecaj, kako na krajobraznu tako i biološku raznolikost, najviše zbog devastiranog prostora koji ostaje nakon zatvaranja eksploatacijskog polja. U ovom radu prikazat će se mogućnosti provedbe prenamjene napuštenih eksploatacijskih polje te prepreke na koje se nailazi u pripremi projektne dokumentacije uključujući i postupak procjene utjecaja zahvata na okoliš na nekoliko konkretnih primjera.
Tiskane pločice (TP) predstavljaju 3 do 5% mase EE otpada, ali su ujedno njegov najsloženiji dio, s najvrijednijim ali i najopasnijim komponentama. Tehnologija recikliranja TP-a s ciljem ...iskorištavanja vrijednih metala je usvojena, no zbog složenosti procesa, ograničeno se primjenjuje. Približno 70% mase TP-a predstavlja nemetalna komponenta (NMF) odnosno plastika, keramika, staklo i slično bez tržišne vrijednosti. Procjenjuje se da u RH godišnje nastane između 350 i 600 t NMF-e. Zbog sastava i sadržaja štetnih spojeva i elemenata opasni je otpad, koji se u nerazvijenim zemljama uglavnom odlaže, dok ga razvijene spaljuju uz znatne troškove.
Rad se bavi ispitivanjem postupka, koji koriste NMF kao sirovinu u proizvodnji betona. Uz kratki pregled zbrinjavanja TP-a i NMF-e, u radu se daje i pregled dosadašnjih svjetskih iskustva u zbrinjavanju NMF inkapsuliranjem u beton ili cement. U radu su prikazani i dobiveni rezultati istraživanja - laboratorijska ispitivanja čvrstoće betona s NMF-om kao punilom. U ispitivanjima se 5% mineralnog agregata supstituiralo NMF-om različite granulacije te se ispitala tlačna čvrstoća kocki starih 7 odnosno 28 dana. Temeljem dobivenih rezultata dane su smjernice za nastavak ispitivanja s ciljem korištenja NMF-a kao repromaterijala.
Učinkovitost inkapsuliranja štetnih tvari određena je ispitivanjem eluata u standardnim uvjetima.
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