Biodegradation of tobacco waste leaves under different composting conditions

[N. Mandić]

87 str.

Tehnološko inženjerstvo - Nauka o preradi ratarskih sirovina / Technological engineering - Science of field crop processing

Cilj ove studije bio je da se ispitaju mogućnosti razvoja prihvatljive tehnike kompostiranja duvanskog otpada mešanjem sa različitim vrstama organskog otpada, za dobijanje proizvoda koji bi imao upotrebnu vrednost u biljnoj proizvodnji. Korišćeni su listovi duvana tipa Virdžinija, koji su na osnovu Merila za klasifikaciju duvana odbačeni kao otpad. Dva eksperimentalna uzorka su formirana mešanjem duvanskog otpada sa ovčijim i kokošijim stajnjakom za kompostiranje u nekontrolisanim uslovima. Četiri eksperimentalna uzorka su formirana su mešanjem duvanskom otpada sa otpadom iz domaćinstva (krompir, mrkva i crni luk) za kompostiranje u nekontrolisanim, polukontrolisanim i kontrolisanim uslovima, sa i bez dodavanja bakterija. Referentni uzorak je bio od čistog duvanskog otpada. Brevibacillus sp. kao soj koji razgrađuje nikotin, prethodno izolovan iz duvanskog otpada, prvi put je korišćen u procesu kompostiranja. Brzina razgradnje nikotina direktno je zavisila od početnog sastava mešovitih kompostnih gomila, prisustva nikotinofilnih bakterija, temperature i vlage u kompostnim gomilama, kao i temperature i vlage okoline. Sadržaj nikotina u finalnim proizvodima nastalih kompostiranjem referentnog uzorka je bio znatno veći od propisane granice (500 mg/kg), čime je onemogućeno njegovo korišćenje. U finalnim proizvodima kod svih mešovitih kompostnih gomila sadržaj nikotina bio je manji od 10 mg/kg. Sadržaj makrohraniva u svim finalnim proizvodima čini ih adekvatnim za poljoprivrednu primenu. Sadržaj toksičnih elemenata kod komposta dobijenih mešanjem duvanskog otpada i životinjskog organskog otpada je ispod referentnih granica. Finalni proizvodi dobijeni kompostiranjem čistog duvanskog otpada, kao i komposti dobijeni mešanjem duvanskog otpada sa otpadom iz domaćinstva, nisu pokazali prihvatljive rezutate u pogledu sadržaja kadmijuma (>3 mg/kg). Najbolje karakteristike imali su finalni proizvodi dobijeni kompostiranjem duvanskog otpada i ovčijeg i kokošijeg stajnjaka u nekontrolisanim uslovima, što je značajno i sa ekološkog i sa ekonomskog aspekta.

The aim of this study was to investigate the possibilities for developing an acceptable technique for composting tobacco waste by mixing it with different types of organic waste to obtain a product that has useful value for crop production. Virginia tobacco leaves that were disposed of as waste according to tobacco classification criteria were used. Two experimental samples were formed by mixing tobacco waste with sheep and chicken manure for composting under uncontrolled conditions. Four experimental samples were formed by mixing tobacco waste with household waste (potatoes, carrots and onions) for composting under uncontrolled, semi-controlled and controlled conditions with and without the addition of bacteria. The reference sample consisted of pure tobacco waste. Brevibacillus sp. as a nicotine-degrading strain, which had previously been isolated from tobacco waste, was used for the first time in the composting process. The rate of nicotine degradation directly depended on the initial composition of the mixed compost piles, the presence of nicotinophilic bacteria, the temperature and humidity in the compost piles, as well as the temperature and humidity of the environment. The nicotine content in the final products obtained by composting the reference sample was significantly higher than the prescribed limit (500 mg/kg), which made their use impossible. In the final products of all mixed compost piles, the nicotine content was less than 10 mg/kg. The content of macronutrients in all final products makes them suitable for agricultural use. The content of toxic elements in composts obtained by mixing tobacco waste and animal organic waste is below the reference limits. The final products obtained by composting pure tobacco waste, as well as compost obtained by mixing tobacco waste with household waste, did not show acceptable results in terms of cadmium content (>3 mg/kg). The best properties were shown by the final products obtained by composting tobacco waste and sheep and chicken manure under uncontrolled conditions, which is important from both an environmental and an economic point of view.

kompostiranje, duvanski otpad, otpad iz domaćinstva, ovčiji stajnjak, kokošiji stajnjak, Brevibacillus sp., nikotin, makrohraniva, toksični elementi

composting, tobacco waste, household waste, sheep manure, chicken manure, Brevibacillus sp., nicotine, macronutrients, toxic elements

663.97.051:633.71(043.3)

Tekst