Atık su arıtma çamurlarının susuzlaştırılması ve stabilizasyonunda kapalı kurutma yataklarının kullanımı
Date
2007
Authors
Salihoğlu, Nezih Kamil
Journal Title
Journal ISSN
Volume Title
Publisher
Uludağ Üniversitesi
Abstract
Ülkemizde atıksu arıtma çamurlarının en yaygın bertaraf yöntemi depolamadır. Mekanik susuzlaştırma ekipmanlarıyla %20–30 Katı Madde (KM) içeriğine ulaştırılan atık çamurlar doğrudan veya kireç ilavesinden sonra düzensiz/düzenli depolama sahalarına depolanmaktadır. Yüksek patojen içeriğine rağmen önemli bir toprak zenginleştirici kaynak olarak düşünülen atıksu arıtma çamurlarının bertaraf maliyetlerini düşürmek amacıyla farklı teknolojiler uygulanmaktadır. Bu çalışmada kapalı kurutma yataklarında güneşle çamur kurutma incelenmiştir. Çalışmanın temelini, ülkemizin güneş enerjisi potansiyelinden yararlanmak ve yenilenebilir enerji kaynaklarının kullanımını artırmak oluşturmuştur. Sistemin kullanımıyla daha az kimyasal sarfiyatı ve düşük maliyetle patojen mikroorganizma giderimi sağlanmıştır. Deneysel süreçte uzun havalandırmalı kentsel atıksu arıtma tesisi çamuru, açık ve kapalı sistemde beton zemin üzerine 25 cm. yüksekliğinde serilmiştir. Çamur kurutma süreci, kontrollü şartlarda incelenmiştir. Haziran –Ağustos döneminde 26 günde %23 Katı Madde (KM) içerikli çamur, açık ve kapalı tesislerde sırasıyla %79 KM ve %91 KM değerlerine ulaşmıştır. Kasım-Aralık döneminde aynı sürede açık tesiste hava şartları sebebiyle %17 KM’ye inilirken, kapalı tesiste %37 KM değerine ulaşılmıştır. KM ile eklenik güneş radyasyonu arasında (R2 >0,9) lineer bir ilişki bulunmuştur. Yaz döneminde kapalı sistemde başlangıçta %20 KM içerikli çamurdaki 107 Koloni Oluşturan Birim (CFU) / g. KM olan fekal koliform konsantrasyonu, Amerikan Çevre Ajansı (USEPA) tarafından belirlenen B sınıfı çamur sınırı olan 2.106 CFU / g. KM değerine 45 günde inmiştir. Sınırlı sönmemiş kireç ( 0,15 kg sönmemiş kireç / kg KM ) ilavesiyle aynı dönemde aynı tip çamurdaki fekal koliform konsantrasyonu 5 günde USEPA tarafından belirlenen A sınıfı çamur sınırı olan 103 CFU / g. KM değerine inmiştir. Depolama kriteri olan %35 KM değerine yaz döneminde kireç ilave edilmeden 10 günde ulaşılmıştır. Çalışma sonuçları, sınırlı kireçlemeyle birlikte gerçekleştirilen kapalı yatakta çamur kurutma sürecinin nihai çamur bertarafından önce ilave çamur susuzlaştırma ve kurutma amacıyla kullanılabileceğini göstermektedir.
Currently, landfilling is the most common method in sludge management in our country. Wastewater treatment sludge (WTS) that have been dewatered up to 20-30% dry solids (DS) content with mechanical dewatering equipment are disposed of at dumpsites or municipal landfills directly or after lime addition. Different technologies to decrease disposal costs can be applied to the WTS that can be considered as an important source with its soil enrichment capacity despite its high pathogen content. Solar sludge drying was examined in this study. The basis for the study was to benefit from the solar energy potential of our country and increase the use of renewable energy sources. Pathogen microorganism concentration and the need for chemical material use were decreased when the system was used. Sludge was obtained from a municipal Wastewater Treatment Plant (WWTP) with extended aeration and spread over the concrete floor in covered and open system with a 25 cm. height. The drying process of the sludge was examined in controlled conditions. In 26 days in June-August period, the DS content of the sludge, which was 23% initially, increased up to 79%DS and 91%DS at open and covered plants, respectively. In November-December period initial 23%DS content of the sludge was decreased down to 17%DS in the open system, and increased up to 37%DS in the covered system, because of the weather conditions. A linear correlation (R2 >0.9) was found between the DS and cumulative solar radiation. Initial fecal coliform value of 107 Colony Forming Unit (CFU)/g.DS of the sludge with 20%DS content decreased down to U.S.Environmental Protection Agency(USEPA) Class B sludge limit, which is 2.106 CFU/g.DS in 45 days in summer period in covered system. By adding quicklime of 0.15kg/kg.DS to the sludge, the EPA Class A sludge limit target of 103 CFU/g.DS was reached in 5 days. 35% DS content target of landfilling was achieved without lime addition at the end of 10 days period of time in summer. The results of the study showed that solar drying in covered sludge drying bed with limited liming would be used for further dewatering and drying purposes before the final disposal of the sludge.
Currently, landfilling is the most common method in sludge management in our country. Wastewater treatment sludge (WTS) that have been dewatered up to 20-30% dry solids (DS) content with mechanical dewatering equipment are disposed of at dumpsites or municipal landfills directly or after lime addition. Different technologies to decrease disposal costs can be applied to the WTS that can be considered as an important source with its soil enrichment capacity despite its high pathogen content. Solar sludge drying was examined in this study. The basis for the study was to benefit from the solar energy potential of our country and increase the use of renewable energy sources. Pathogen microorganism concentration and the need for chemical material use were decreased when the system was used. Sludge was obtained from a municipal Wastewater Treatment Plant (WWTP) with extended aeration and spread over the concrete floor in covered and open system with a 25 cm. height. The drying process of the sludge was examined in controlled conditions. In 26 days in June-August period, the DS content of the sludge, which was 23% initially, increased up to 79%DS and 91%DS at open and covered plants, respectively. In November-December period initial 23%DS content of the sludge was decreased down to 17%DS in the open system, and increased up to 37%DS in the covered system, because of the weather conditions. A linear correlation (R2 >0.9) was found between the DS and cumulative solar radiation. Initial fecal coliform value of 107 Colony Forming Unit (CFU)/g.DS of the sludge with 20%DS content decreased down to U.S.Environmental Protection Agency(USEPA) Class B sludge limit, which is 2.106 CFU/g.DS in 45 days in summer period in covered system. By adding quicklime of 0.15kg/kg.DS to the sludge, the EPA Class A sludge limit target of 103 CFU/g.DS was reached in 5 days. 35% DS content target of landfilling was achieved without lime addition at the end of 10 days period of time in summer. The results of the study showed that solar drying in covered sludge drying bed with limited liming would be used for further dewatering and drying purposes before the final disposal of the sludge.
Description
Keywords
Atıksu arıtma çamuru, Güneşle kurutma, Katı madde, Fekal koliform, Wastewater treatment sludge, Solar drying, Dry solids, Fecal coliform
Citation
Salihoğlu, N. K. (2007). Atık su arıtma çamurlarının susuzlaştırılması ve stabilizasyonunda kapalı kurutma yataklarının kullanımı. Yayınlanmamış doktora tezi. Uludağ Üniversitesi Fen Bilimleri Enstitüsü.