What are solid waste?
The solid waste is the material that does not represent a utility or an economic amount for the owner. Solid waste is one of the most prominent social problems today due to the poor disposal or location of waste or debris that causes commercial and industrial activity and the daily life of the population, forming what is called garbage.
Sources and types of solid waste
- Domestic: they are located in single-family and multi-family dwellings, buildings, among others; in these we find food waste, paper, cardboard, plastic, textiles, leather, garden waste, wood, glass, items such as furniture, lamps, televisions, etc., batteries, batteries, used oils and hazardous household waste.
- Commercial: they are located in stores, restaurants, markets, office buildings, hotels, printers, etc; in these are residues such as cardboard, plastic, glass, metals, special waste such as cabinets, lamps, washing machines, dryers, batteries, tires, etc.
- Institutional: are located in government agencies such as schools, hospitals, military areas, prisons, etc .; we find waste such as paper, cardboard, wood, food waste, glass, metals, special and bulky waste and hazardous waste.
- Constructions: new places of construction of buildings, places of demolition of structures such as buildings, houses, streets, bridges, etc .; you can find waste such as stones, concrete, bricks, wood, gravel, heating and electricity parts, broken glass, plastics, steel parts, etc.
- Municipal Services: cleaning streets, avenues, parks, beaches, etc; this waste is mostly cuttings from trees and other vegetables, scrap, waste from water collectors, general waste from cleaning parks, avenues, streets, beaches, etc.
- Treatment Plants: they are observed in places of treatment plants of white, black and industrial waters, and municipal incinerators; in this we find waste from treatment plants such as sludge, ash and rejects, coal slag, remains of partially incinerated materials, etc.
- Industrial: they are located in constructions and demolitions, manufacture of light and heavy items, refineries, chemical plants, thermal power plants, etc; these generate waste from industrial processes such as scrap materials, non-industrial waste such as food, cardboard, plastic, ash, construction and demolition waste, special waste, hazardous waste, etc.
- Agricultural: They are located in crops and crops mainly producing waste resulting from agricultural processes, as well as remains of manure, pesticides, fertilizers, etc.
Classification by type of management
• Hazardous waste: are those that by their nature can not be handled easily because they can cause illness or even death if they are mishandled.
• Pathogen Solid Residue: those that due to their characteristics can be reserves of diseases for humans.
• Toxic Solid Residue: Due to their physical and chemical characteristics they can cause damage to the environment and even the death of human beings.
• Inert waste: it is stable over time which will not produce appreciable environmental effects when interacting in the environment.
• Non-hazardous waste: A solid "non-hazardous" waste is considered to be those coming from dwellings, private and public service sites, demolitions and constructions, commercial establishments and services that do not have harmful effects on human health.
Waste management
Waste management, referred to household waste, aims to achieve the maximum practical benefit of the products and generate the minimum possible amount of waste, we can classify it in the so-called The 3Rs: Reduce, Reuse, Recycle or in the control of the generation, storage, collection, transfer and transport, processing and dumping of solid waste.
According to the named classification we have:
- Manipulation at the source: (Separation, storage and processing) Activities associated with the handling of this waste until storage, in this the waste is kept in suitable containers until collection. The processing is done in order to reduce the volume of waste, altering its physical form for the storage of them and recover materials such as (compaction, crushing and separation). The separation is used to transform homogeneous mixtures into more homogeneous fractions.
- Collection: Understands the process of collecting the waste already stored, transferring it to the collection vehicle and finally unloading it at a transfer station or at the final disposal site.
- Transfer and transport: comprises in two stages:
- The transfer of waste from collection compactor vehicles to larger vehicles at a transfer station.
- Transportation of waste: from the transfer station to the processing centers or to the final discharge site.
It is an effort to reduce harmful effects on human health and the aesthetics of the environment, although at present work is being done to reduce the harmful effects caused to the Environment and to recover its resources.
Waste management can involve solid, liquid or gaseous substances with different methods for each one. The waste can be classified as: domiciliary, industrial, agricultural and hospital, each of these waste is managed differently.
Waste management also covers Hazardous Waste Management.
Waste management differs for developed and developing countries, for urban and rural, residential, industrial and commercial producers. The management of non-hazardous waste for residential areas or in metropolitan areas is generally the responsibility of the local government, while non-hazardous waste from the industry is the responsibility of the waste generator itself.
Hazardous Waste Management
It is the set of processes applied to develop an adequate management of chemical and physical residues capable of potentially causing damage to human health and the environment. One of the causes of waste growth is the creation and evolution of the industry that has been expanding over the years.
According to this management, waste has been classified as:
• Toxic waste: causes harm to human health and the environment.
• Chronic waste: causes permanent effect for human health and the environment.
• Flammable waste: it is a waste that can generate fires or accidents.
• Corrosive waste: it is a residue whose physical contact causes burns or erosions.
• Reactive waste: this waste has a chemical characteristic that makes it unstable to changes in its environment.
• Radioactive waste: is a special class of waste product of nuclear generation plants, devices used in hospitals, or specific measurement, using radioisotopes or product of a process of manufacturing nuclear weapons or nuclear power plants
Sanitary landfills
They are works developed with the purpose of depositing the urban solid waste and thus avoiding the massive contamination of the environment, the latter being the main factor of the construction. Landfills comply with special measures for their construction, such as a detailed study of environmental, economic and social impact from planning and choosing the place to the monitoring and study of the place throughout the life of the landfill.
The sanitary landfill is used to compress the garbage as much as possible and covering it with a layer of earth or other materials of 40 cm thick, thus placing other layers of garbage consecutively until the landfill. Landfills can be classified as:
• With or without crushing.
• With or without leachate compaction.
• With or without prior selection.
• With or without gas recovery
Advantages of sanitary landfills:
• Low initial cost, operation and maintenance.
• Use of land that has been considered unproductive or marginal.
• Solve the problem, complete and definitive, to numerous important municipalities that are still overwhelmed by numerous costs; fumes, smells, plagues, public nuisances that are generated with other methods of garbage disposal.
• A sanitary landfill can begin to work in a short time as a disposal method.
• It is considered flexible, since it does not require permanent and fixed installations.
Disadvantages of landfills:
• It must have a good planning and above all at the citizens' awareness level.
• Potential contamination of nearby ground and surface water can occur if proper precautions are not taken.
• Obstructions in population growth trends.
• Settlements of unstable villages occupied by cracks that subsist on the materials they select from the waste.
Environmental impacts and mitigation
An environmental impact can be defined as the effect that produces some human action on the environment, whose action is harmful in the short or long term. Environmental impact assessments are a set of techniques that seek to manage human affairs in a way that creates a balance or harmony with nature.
Within these environmental assessments are developed two techniques that are environmental impact assessment (EIA) which is the analysis of the predictable consequences of the action and the declaration of environmental impact (EIS) which is prior communication, which environmental laws require under certain assumptions, of the environmental consequences predicted by the evaluation.
The management of the environment implies a relationship with various scientific activities in turn this management has two specific application areas:
• A preventive area: in this the environmental impact study is an effective tool.
• A corrective area: in this the environmental audits make up the methodology of analysis and action to correct the existing problems.
Mitigation
Through mitigation, the aim is to reduce the loss of lives and property through the analysis of risks and disasters that are the result of information that provide a basis to ensure economic investments.
The FEMA mitigation division manages the National Flood Insurance Program (NFIP) and implements a variety of programs authorized by Congress to reduce the losses that could result from natural disasters. Effective mitigation efforts can break the cycle of disaster damage, reconstruction and repeated damage.
Shocking news on solid waste
In May 1990, 400 homes next to the toxic waste dump of Love Canal, in Niagara Falls, New York State, had to be evacuated forever, and the entire neighborhood was isolated due to the heavy contamination of the toxic chemicals. The city itself, which is a center of chemical industries, and yet received contamination of substances from other landfills of toxic waste.
Summer of 1987, a garbage barge from the Long Island Sound (New York City) tried to unload its 10,000 tons of waste in six US states and in five different countries. After traveling almost 10,000 kilometers was forced to return to New York because nobody wanted to keep their merchandise.
Venezuela will improve the integral management of municipal solid waste at the national level with a partially funded program, it is anticipated that with the implementation of the project, in five years some 1100 tons per day that are now disposed in open dumps, will have a final disposition in environmentally regulated sanitary landfills that will be built with program funds. It is estimated that the level of separation for recycling, in these tons, will be raised by at least 20% at the conclusion of the project.
In Venezuela Less than 10 percent of solid waste is recovered, which gives an idea of how much garbage goes to landfills. In Venezuela there are more than 300 official dumps and more than a thousand clandestine dumps.
One of the most emblematic landfills in the Carabobo State is La Guásima, in Libertador, where the waste of four large municipalities, including the one that administers it, goes to waste. There the open-air sanitation began, whose project is executed in a first phase.
Venezuela requires around 150 landfills to meet the current need for final disposal of solid waste. Of those that exist, only one complies with environmental and health regulations.
Proposal to create a sanitary landfill in any city
The basic principle of the functioning of a sanitary landfill is the application of engineering principles to confine the garbage, reducing its volume (to the minimum practicable) and covering the garbage with a layer of earth at the end of each day. This must have:
A biogas drainage system that aims to evacuate methane gas and other fermentation (mainly anaerobic) that are formed inside the mass accumulated over time. This would prevent the spontaneous combustion that occurs in the garbage, which causes air pollution.
A leachate collection design, because if the thickness of the soil between the base of the landfill and the groundwater fails to mitigate the high polluting power of the leachate, it will contaminate the groundwater, thus altering its physical, chemical and biological characteristics.
A water drainage system designed to reduce as much as possible the amount of water that reaches the different parts of the area of the landfill area, either by direct precipitation, by water runoff from adjacent land, by floods of rivers or streams and by filtering the sub-soil of the filling.
Currently the correction to the lack of sanitary landfills must be made through the development and implementation of a proper Comprehensive Urban Solid Waste Treatment Plan, which includes among other things the training of the population in techniques of recycling, sorting and separation of waste, correct disposal, analysis of the type of waste generated and formulation of preliminary projects for final disposal sites for solid urban waste, with all the basic technical studies and evaluation of environmental impacts.
It should be noted that there are some developed countries in North America, Europe and Japan that have developed techniques to improve the operation of landfills. However, the markets of developing countries, Asia and Latin America, are growing rapidly as the environmental issue becomes a priority. Developing countries with growing populations and rapid advances need environmental goods and services. In addition, international aid agencies are placing emphasis on sustainable development and environmental performance in their financial support programs.
Source
- A world in balance. The pollution of our planet. Jon Erickson
Mc Graw series - hill. - Basic foundations of environmental processes for engineers. Jose Andres Roa Marquez.