Learn how wastewater treatment works in Brazil | Sciences

In 1892, . was released health service, of the Minister of State for Internal Affairs. The agency’s mission was to promote, at the federal level, the study of public health issues, and Sewage From localities and residences and adopting means against them Infectious diseases.

In 1934, during Getúlio Vargas . government, the decree establishing the Water Law was approved, valid until today. Makes law official, among the various uses of Water Resources National authorities, recommending the avoidance of water pollution – consider it the basis of public sanitation management.

From the 1940s onwards, the first autonomous systems and financing mechanisms for water supply appeared, and later state water and wastewater companies appeared.

Here is how the sewage treatment process works in the country today:

Primary treatment Corresponds to the removal of suspended solids, floating solids and portions of matter organic.

1. rough grating Upon reaching the wastewater treatment plant (ETE), the collected waste passes the first step of the network. In a duct or duct located in the basement of the station, the liquid passes through networks that act like sieves, holding solids such as bottles, pieces of wood and plastic.

two. Raw sewage pumping station After the first network, the sewage is pumped to the top of the station. In this section, within the channels, a fine secondary grating occurs, where solids Palace like leaves, cartoon and fabrics.

3. desander / sand The sewage flows slowly through sandbox. It resembles a large, rectangular, open pool, in which denser grains of sand sink to the bottom and are pumped out.

secondary treatment It removes a large part of the organic matter and some parts of the nutrients such as nitrogen and phosphorous.

4. Anaerobic Decomposition Reactors The wastewater then goes to the reactor tanks, which are closed like big boxes. Water. At this time, decomposing anaerobic bacteria enter the scene, which digest between 60% and 75% of the solid organic matter. From this decomposition, part of the material accumulates at the bottom as primary sludge, which is treated in the solid phase. Another part is converted to Carbon Dioxide and methane gas burned in a particular plant.

5. aeration basins After anaerobic decomposition, the effluent effluent moves to new tanks, this time open, where the aerobic bacteria. For this, it is necessary to pump air inside liquid. This further decomposition results in the formation of secondary sludge.

6. Secondary beaker After decomposition two before MicroorganismsThe waste water goes to another beaker, which precipitates the sludge at the bottom of the container and sucks it up by pumps. It is an open tank with a rotating screen, which helps filter the sludge. After this step, the liquid part of the sewage is 90% free. solid impurities.

The third treatment Removes organic matter, nutrients and pollutants, and completes wastewater disinfection.

7. Purification After a lot of organic matter has been removed, it’s time to disinfect the wastewater, eliminating it Disease-causing microorganisms. In the tank, the liquid is exposed to ultraviolet rays that kill germs such as bacteria, viruses, and primitive beings Pathogenic, or chemical agents which have the same purpose. After disinfection, the sewage is considered clean to be finally released into rivers and streams.

1. Dry house All the sludge collected in the ETE is transported to the dehydration house, where it undergoes for the first time a new process MoldingTo remove the water and then the drying process. This makes it easier to transport them to landfills.

two. Resubmit The part of the sludge that has not been digested in the whole process is re-entered into the ETE of the pumping station, and goes through the whole process again