The garbage produced in cities, whose collection is managed by the local administration, is classified as Urban Solid Waste (USW). Brazil produces, per day, close to 150,000 tons of garbage (77% of residential origin). According to ABREPE (Brazilian Association of Public Cleaning and Special Waste Companies), 60.5% of Brazilian municipalities are inappropriately accumulating their solid waste.
In most of the country, garbage is sent to dumps, which are areas where garbage is simply piled up, without care for the separation of organic and inorganic products, or with the recycling and treatment of waste that can contaminate soils, rivers and aquifers. The places where the garbage is covered with earth are called controlled landfills, a technique that does not ends with contamination, only inhibits the bad smell and the proliferation of insects and animals vectors of illnesses.
The most suitable systems for the disposal of waste are landfills. Landfills are built in locations far from springs and residential areas. Its base structure is made up of waterproofing materials, such as PVC, so that the slurry - liquid formed by the decomposition of garbage - do not infiltrate underground, and can even be reused through the composting system for the production of fertilizers and fertilizers natural.
Another advantage of landfills is the use of gases from the decomposition of organic waste, the main one being methane, classified as one of the largest greenhouse gases. Biogas is a renewable energy source and is part of the clean development mechanisms provided for in the Kyoto Protocol. The pioneer project in Brazil to use biogas as a carbon credit is the Nova Iguaçu Waste Treatment Center, in the state of Rio de Janeiro.
Sanitary landfills have a high cost and a specific period for their use, on average between 20 and 30 years. The logistics involved in transporting garbage to areas far from urban centers is one of the more complex components to be solved, especially in the congested traffic of large cities. Another costly option from a financial point of view is the incineration of waste, an option widely used in countries like Japan and Australia. Modern waste combustion facilities are designed to destroy waste and recover energy, which is used to produce steam and electricity.
In 2010, the Brazilian government instituted the National Solid Waste Law, which stipulated, in 2014, the deadline for all municipalities in the country have a correct destination for their waste, replacing all dumps with landfills Sanitary. City halls need to present their projects so that the Federal Government can offer part of the resources necessary for their implementation. Unfortunately, Brazil does not have greater institutional support for selective garbage collection, which represents the of materials that can be reused, recycled or recovered, such as paper, plastics, metals, glass, among others.
It is up to independent cooperatives, or those linked to the government, to carry out this separation of waste before it is sent to landfills, or to the common sense of the population in carrying out this separation. Not to mention the thousands of people who, in conditions of underemployment, carry out the arduous task of separating waste that can be resold, such as cardboard and aluminum. Recycling and reusing materials removes waste that could accumulate in dumps, rivers and streams, also helping to save energy used for the transformation of raw material.
Julio César Lázaro da Silva
Brazil School Collaborator
Graduated in Geography from Universidade Estadual Paulista - UNESP
Master in Human Geography from Universidade Estadual Paulista - UNESP
Source: Brazil School - https://brasilescola.uol.com.br/geografia/saneamento-basico-questao-lixo.htm
