World Applied Sciences Journal 30 (11): 1689-1693, 2014 ISSN 1818-4952 © IDOSI Publications, 2014 DOI: 10.5829/idosi.wasj.2014.30.11.14234 Corresponding Author: Polina Yurjevna Galitskaya, Kazan Federal University, Kremlevskaya Str, 18, 420008, Kazan, Russia . 1689 The Effectiveness of Co-Digestion of Sewage Sludge and Phytogenic Waste Polina Yurjevna Galitskaya, Polina Alexandrovna Zvereva and Svetlana Yurjevna Selivanovskaya Kazan Federal University, Kremlevskaya Str, 18, 420008, Kazan, Russia Submitted: Dec 5, 2013; Accepted: Feb 7, 2014; Published: Feb 28, 2014 Abstract: The authors explore the effect of the composition of mixtures of sewage sludge and phytogenic waste, their preliminary inoculation with a methanogenic community and the length of the process on biogas release in anaerobic co-digestion in thermophilic conditions. The study determines the effect of co-digestion products on the soil microbial community, as well as biometric parameters of the oat plants (Avena sativa L.). The authors demonstrate the principal possibility of co-digestion of the wastes. In terms of biogas release, the most preferable is the mixture of sewage sludge and maize silage. This mixture’s co-digestion products possess fertilizing qualities. Key words: Anaerobic co-digestion Organic waste Biogas Non-traditional fertilizers INTRODUCTION sewage sludge, while in the Russian Federation sludge is The buildup of household and industrial waste is a sewage waters, which leads to the buildup of toxicants in topical ecological issue [1, 2]. Much of the waste that them [14]. The effectiveness of co-digestion of such forms is organic [3]. Development of ways of waste sludge and its mixtures with phytogenic waste has been treatment is among the promising dimensions allowing explored insufficiently. us to achieve both the ecological and economic effect. The purpose of this work is to provide an analysis of One of the ways of organic waste utilization is anaerobic the efficacy of co-digestion of the anaerobic processing co-digestion [4]. This type of processing has a number of of sewage sludge and phytogenic waste. advantages: formation of less secondary waste compared with aerobic utilization; effective processing of moist MATERIALS AND METHODS (60% and more) waste; elimination of pathogenic organisms, especially using multistage reactors or using The object of the study is sewage sludge (SS), the intermediary stage (pasteurization); the possibility of mixtures of SS and maize silage that has lost its using fermentation products as fertilizers; formation of consumptive qualities and sunflower husks (Table 1). ecologically clean fuel – biogas [5, 6, 7, 8]. The samples were co-digested adding a 10% (mass-wise) The characteristics of waste have a substantial inoculate (a fermentative mass after a previous co- effect on both the co-digestion process and biogas digestion). One of the variants of the experiment release. These characteristics include: the content and envisaged the co-digestion of SS with no inoculates. composition of the organic substance, the size of the Anaerobic co-digestion was performed in particles, moisture, pH, the presence of toxic and hermetically sealed vessels under 55.5°C. Every 12 hours, decomposition-resistant substances, etc. [2, 9, 10]. the vessels were stirred for 30 seconds. Fermentation was Negative factors can be overcome through the performed for 14 and 21 full days. Prior to incubation, the co-digestion of waste that possesses various pH of the mixtures was adjusted to 7.5 with milk of lime. characteristics [10]. The increase in biogas release The moisture content of the initial mixtures was 92-96%. through the co-digestion of household sewage sludge In assessing the fertilizing qualities of fermentation and agricultural production waste has been demonstrated products, they were introduced into urban soil (in a dose by a number of authors [11, 12, 13]. Having said that, most of 30 t/ha), which was first moistened to 60% of overall major publications are dedicated to the digestion of moisture-holding capacity and incubated under room formed in cleansing mixed (industrial and household)