Estudo do comportamento de aterros de RSU em um biorreator em escala experimental na cidade de Campina Grande-PB.

Abstract

Municipal Solid Waste (MSW) has caused serious social and environmental problems in the cities of Brazil and the world. The absence of a policy on management of solid waste has deepened this issue. It is known that the characteristics of solid waste change from town to town depending on the economic, cultural and social situation, the study of the area and the influence of seasonality and climate of the region. Information found in the waste biodegradation in a given location can’t be generalized to any region, requiring a development of a specific study for each place. Experimental cells (lysimeters) enable the understanding of the behavior of MSW landfills, and represent a very interesting technique to obtain parameters for a project, dimensions and construction of dumps. They can also offer contribution in the sanitation field through the monitoring of processes. The objective of this survey is to examine the behavior of main MSW landfills, studying a lysimeter in experimental scale. The lysimeter was built in the city of Campina Grande-PB. The geotechnical aspects and evolutionary process of degradation were evaluated in the deposited waste. For this reason a cylindrical lysimeter was constructed. It has an internal volume of approximately 1.7 m3 and was built in the EXTRABES experimental field sited in the city of Campina Grande. The lysimeter was filled with previously characterized solid waste from different areas of the city. The data was obtained through installed instrumentation and collection of solid samples analyzed in laboratory. The lysimeter was equipped with liquid and gas drainage systems, a liquid level measuring system, structures that measure the settlement of the soil, systems that measure temperature along the depth with the assistance of thermocouples and a gas drain. The monitoring of the experimental cell involved measurements in the lysimeter and periodic collection of solid samples for laboratory testing. The parameters analyzed were: humidity rate, volatile solids, pH, volatile fatty acids, total alkalinity, chloride, COD, BOD, phosphorus, nitrite, ammonia nitrogen, concentrations of microorganisms (fungi and totals aerobic), tests of phytotoxicity, macronutrients, micronutrients, metals, organic substance and carbon. The results showed that the deployment of the instrumentation was essential for the monitoring of the lysimeter, enabling the improvement, adaptation and development of methodologies, equipment and tools. There was a correlation between certain parameters, in particular climatic conditions, concentrations of microorganisms and magnitude of soil settlement. It was observed that the behavior of the majority of the examined parameters, despite fluctuations and particularities, was consistent with the results obtained in the technical literature. These results may help with data for the installation of a landfill in the city of Campina Grande. The city doesn’t have a landfill to dispose the waste generated, in order to satisfy the environmental standards and guidelines. The waste is deposited in open lands.