Evaluation of gamma irradiation for bio-solid waste management

Abstract

Gamma irradiation is a form of pure energy which is currently used most widely for food and waste irradiation. To evaluate the potential of gamma irradiated sludge for its suitability as a soil amendment in agriculture, field experiments were carried out in a root crop, carrot (Daucus carota). Treatments consisting of three sources of manure (Farmyard Manure (FYM), gamma-irradiated sewage sludge and non-irradiated sewage sludge), each at three different levels (5, 10 and 15 t ha-1), were compared. The growth parameters and yield of carrot was not significantly influenced by the three sources of manure or their different levels. Values for EC, pH, organic carbon, total N, available P and K, metallic micronutrients (Zn, Mn, Fe, Cu) and heavy metals (Ni, Cd, Pb, Co) indicate no adverse effect on soil properties.

Potential of Gamma Irradiated Sewage Sludge as Fertilizer in Radish: Evaluating Heavy-Metal Accumulation in Sandy Loam Soil

“…As a result of large-scale urbanization and industrial development, the generation of sewage sludge has increased rapidly during the past few decades (Rathod et al 2008;WWAP 2003). Governments throughout the world are facing a problem of management and disposal of a large quantity of sewage sludge (Mor et al 2006a;USEPA 1993).…”

“…Governments throughout the world are facing a problem of management and disposal of a large quantity of sewage sludge (Mor et al 2006a;USEPA 1993). High cost of land filling of sewage sludge and a ban on ocean dumping in a few countries are some factors that contribute to recycling of sewage sludge (Harrison, McBride, and Bouldin 1999;Rathod et al 2008). Sewage sludge is a cheap source of appreciable amounts of plant nutrients and organic matter (Gautam et al 2005).…”

“…On an average, sewage sludge contains about 3.2% nitrogen (N), 2.3% phosphorus (P), and 0.3% potassium (K); and therefore during the past two decades, the use of sewage sludge as fertilizer increased in many countries (Hornick et al 1984;Krogman et al 1997). However, the direct use of sewage sludge has a few environmental and public health concerns (Dewil, Baeyens, and Neyens 2006) because of the presence of heavy metals, pathogenic bacteria, and other toxic substances that may limit its application as soil fertilizer (Wen et al 1995;Rathod et al 2008). Another concern is groundwater contamination because of heavy-metal infiltration by precipitation from soil-applied sewage sludge (Mor et al 2006b).…”

“…The rationale for utilizing radiation in treatment of sewage sludge rests on a number of documented facts. Many practical advantages of gamma-irradiated sewage sludge (GISS) have been documented (Rathod et al 2008). On the other hand, if municipal sewage sludge is disposed of untreated, it may result in public health hazards as it contains a high load of heavy metals, pathogenic bacteria, and viruses (Pike 1986;Ahmed and Sorensen 1997), in addition to useful major and micronutrients (Jung, Thornton, and Chon 2002).…”