FACTORS AFFECTING THE BIODEGRADATION EFFICIENCY OF SOLID WASTES: “COMPACTION AND SHREDDING OF SOLID WASTES”

Öz

In this study, the effects of shredding and waste compaction on the anaerobic treatment of domestic solid waste and leachate characteristics was investigated in three simulated landfill anaerobic bioreactors. All of the reactors were operated with leachate recirculation. One of them was loaded with raw waste (control reactor); the second reactor was loaded with shredded waste having a diameter of 0.5-1cm (shredded reactor); the third reactor was loaded with compacted waste (compacted reactor). The leachate recirculation rate was 300 ml/day in all of the reactors. pH, chemical oxygen demand (COD), volatile fatty acids (VFA), ammonium nitrogen (NH4-N) concentrations; total and methane gas productions in the leachate samples were regularly monitored. After 57 days of anaerobic incubation, it was observed that the pH, COD, VFA concentrations, and BOD5 /COD ratio in the leachate of shredded reactor were better than the control and compacted reactor. The COD values were measured as 6400, 7700 and 2300 mg/l while the VFA concentrations were 2750, 3000 and 354 mg/l, respectively, in the leachate samples of the control, compacted and shredded reactor after 57 days of anaerobic incubation. The values of pH were 6.88, 6.76 and 7.25, respectively, after anaerobic incubation, respectively in the aforementioned reactors. It was observed that the waste shredding increased the methane percentage in the anaerobic simulated reactor. Methane percentage of the control, compaction and shredded reactors were 36 %, 46 % and 60 %, respectively, after 57 days of incubation. A BOI5/COD ratio of 0.44 was achieved in the shredded reactor indicated the better MSW stabilization resulting in a high rate than that of compacted and control reactors. It was observed that waste shredding reduced the waste quantity, the organic content of the solid waste and the biodegradation time

Anahtar Kelimeler

• Municipal solid waste, Simulated anaerobic bioreactor, Leachate recirculation, Waste shredding, Waste compaction

KATI ATIKLARIN SİMÜLE BİYOREAKTÖRLERDE AYRIŞMASINI ETKİLEYEN FAKTÖRLER: "KATI ATIKLARIN SIKIŞTIRILMASI VE PARÇALANMASI"

Öz

Bu çalışmada anaerobik simüle biyoreaktörlerde katı atıkların sıkıştırılması ve parçalanmasının katı atık arıtımına ve sızıntı suyu özelliklerine etkileri üç adet biyoreaktörde incelenmiştir. Tüm reaktörler sızıntı suyu geri devirli çalıştırılmıştır. Reaktörlerden birine ham atık (kontrol reaktör), ikincisine 0.5-1cm boyutlarında parçalanmış atık (parçalamalı reaktör), üçüncüsüne ise sıkıştırılmış katı atık (sıkıştırılmış reaktör) yüklenmiştir. Tüm reaktörlerde sızıntı suyu geri devir oranı 300 ml/gün’dür. pH, kimyasal oksijen ihtiyacı (KOİ), uçucu yağ asidi (UYA), amonyum azotu (NH4-N), toplam ve metan gazı üretimleri düzenli olarak izlenmiştir. 57 günlük inkübasyon süresi sonunda pH, KOİ, UYA, BOİ5/KOİ oranları açısından parçalamalı reaktörün diğer reaktörlerden daha iyi olduğu gözlenmiştir. Kontrol, sıkıştırmalı ve parçalamalı reaktörlerden elde edilen sızıntı sularında 57 günlük anaerobik inkübasyon sonucu gözlenen KOİ değerleri sırası ile 6400 mg/l, 7700 mg/l ve 2300 mg/l, UYA değerleri ise 2750 mg/l, 3000 mg/l ve 354 mg/l’dir. pH değerleri sırası ise sırası ile 6.88, 6.76, 7.25 tir. 57 günlük inkübasyon süresi sonunda kontrol, sıkıştırmalı ve parçalamalı reaktördeki metan yüzdeleri, % 36, % 46 ve % 60’tır. BOİ5/KOİ oranı 0.44 olan parçalamalı reaktör diğer iki reaktörden daha yüksek ayrışma hızına sahiptir. Yapılan deneyler parçalamalı reaktörlerin atık miktarı, organik madde azalması ile atık ayrışma zamanı açısından diğer iki reaktöre kıyasla daha iyi olduğu gözlenmiştir

Anahtar Kelimeler

• Kentsel katı atık, Simule anaerobik biyoreaktör, Sızıntı suyu resirkülasyonu, Atık parçalanması ve sıkıştırılması

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