Atıksu arıtma tesislerinde, arıtma işlemleri sonucunda oluşan arıtma çamurlarının anaerobik yöntemlerle stabilizasyonu; atık bünyesindeki organik madde içeriği ve patojen mikroorganizma konsantrasyonunun azaltılması amacıyla günümüzde yaygın olarak kullanılan bir yöntemdir. Anaerobik çürüme uygulamasının derecesine bağlı olarak çok faydalı bir son ürün olan ve temiz enerji kaynağı olarak nitelenen biyogaz eldesi mümkün olmaktadır. Anaerobik çürüme prosesinin oldukça yavaş bir süreç olması ve çürüme sonrasında organik maddelerin tümüyle parçalanamaması nedeniyle tam stabilizasyonun sağlanamaması ve elde edilen biyogaz miktarının az olması araştırmacıları anaerobik çürümeyi hızlandıracak ve stabilizasyon derecesini artırmayı sağlayacak yeni yöntemler geliştirmeye yöneltmiş ve çamur ön arıtımı amacıyla kullanılan bir yöntem olarak çamur dezentegrasyonu geliştirilmiştir. Dezentegrasyon işleminde, çamura uygulanan gerilmeler sayesinde çamur flok yapısı bozulmakta, mikroorganizma hücre duvarları parçalanmakta, hücre içeriğindeki organik çamur bileşenleri sıvı faza geçmektedir. Dezentegrasyon sonucunda, çamur katılarının organik madde içeriği en aza inmekte, dolayısıyla daha düşük miktarda ve daha stabil bir çamur eldesi mümkün olmaktadır. Organik maddenin yüksek derecede parçalanması klasik anaerobik çürüme işlemine göre daha fazla biyogaz üretimine olanak sağlamaktadır. Bu çalışmada anaerobik arıtma öncesinde çamura bir ön arıtma işlemi olarak uygulanan dezentegrasyon işleminin mekanizması ve amaçları özetlendikten sonra dezentegrasyon yöntemleri hakkında bilgi verilmiştir. Anahtar Kelimeler: Çamur, anaerobik çürüme, dezentegrasyon.The main by-product of municipal wastewater treatment of waste activated sludge (WAS) has been increasing worldwide as a result of an increase in the amount of wastewater being treated. Treatment and disposal of excess sludge in a biological wastewater treatment system has enormously high cost which has been estimated to be 50?60% of the total expense of wastewater treatment plant (Egemen et. al., 2001). Anaerobic digestion is a common process for stabilization of treatment plant sludges. Compared with other processes, its advantages are less energy required, a better stabilized product, and usable gas. Anaerobic digestion process is achieved through several stages: hydrolysis, acidogenesis, methanogenesis. For waste activated sludge degradation, the rate-limiting stage is the hydrolysis. Biogas considered as the clean energy source is produced in the anaerobic digestion process depending on the stabilization degree. Anaerobic digestion is a slow process, which results in a long residence time and the requirement of a large tank volume. In order to improve hydrolysis and anaerobic digestion performance disintegration was developed as the pretreatment process of sludge to accelerate the anaerobic digestion and to increase degree of stabilization (Bougrier et. al.,2005) . Disintegration process results in an improvement of velocity and degree of degradation. To increase of stabilization degree of sludge with disintegration process provides less sludge production, more stable sludge and more biogas production comparing the classical anaerobic digestion. Sewage sludge disintegration can be defined as the destruction of sludge by external forces. The forces can be of physical, chemical or biological nature. As a result of the disintegration process is numerous changes of sludge properties (Müller et. al., 2004). Disintegration cause disruption of microbial cells in the sludge, thereby destroying the cell walls (Vranitzky et. al., 2005). The destruction of floc structure and disruption of cells results in the release of organic sludge components into the liquid phase. These components exist in a dissolved phase, e.g. components of intracellular water, or can be liquefied. Particle size or colloidal components may still be present within the solution because they cannot be separated from the liquid phase. Their minute particle size and only a slight difference in density of particle and surrounding water are the cause. But components are easily biodegradable on the other hand. Since they are already liquefied or offer a large surface in comparison their volume, the hydrolyzing process is simple. Released carbon compounds after disintegration are easily accessible and can be digested much faster in later biological process than sludge in a particular phase. The results are shorter degradation times and higher degrees of degradation during the aerobic and anaerobic stabilization. Besides, these compounds can further be used for carbon limited process steps within the wastewater treatment such as denitrification or the biologically enhanced phosphorus elimination. After disintegration, the liquid phase has to be cleaned from the released nitrogen and phosphorus compounds before leaving the treatment plant. If this happens by returning the water into the WAS-process, additional capacities have to be taken into account. Disintegration within the sludge pre-treatment has advantages in combination with selective recyling processes due to the increased nitrogen and phosphorus concentrations (Müller et. al., 2004). In recent years, for the purpose of waste activated sludge (WAS) minimization and more biogas production than classical anaerobic digestion, several disintegration methods have been investigated. The methods can be classified as following topics; - Chemical disintegration (Ozone treatment, Alkaline treatment, Fenton process etc.) - Mechanical disintegration (Stirred ball-mill, High-pressure homogenizer, Ultrasonic Homogenizers, Lysatcentrifuge, Jet Smash Technique, The High Performance Pulse Technique etc.) - Thermal disintegration - Biological disintegration (High temperature sludge stabilization with thermophilic bacteria, Enzymatic lysis). In this study, the mechanisms and objectives of disintegration process was summarized and then disintegration methods were evaluated. Keywords: Sludge, anaerobic digestion, disintegration
