The main effect of the trash is to prevent waste, leaves and other objects falling into the sewer system below; Or flow into the house when it rains heavily and flooded. These types of garbage have the potential to cause sewer blockage and drainage systems; Flooding for roads and neighborhoods. Therefore, the trash is an indispensable item in the production and treatment system of production and daily life.

Song trash is usually made of cast iron, composite or grating steel ...

Depending on the purpose of the user, it is divided into many types such as: Song trash, but raw trash.

Song trash or garbage shields are usually installed in front of pumping tanks. They are made of small steel bars, or steel sheets are pounded; Or composite, cast iron with many spokes and gaps with a section of 5*20 mm; distance of 20-50mm. These rectangles are often rectangular to facilitate sliding up and down in the fixed slot of the reservoir door. This barrier is usually perpendicular to the water stream, or it is inclined 45 - 60 degrees compared to the vertical vertical with a wide mesh about 10-20 mm.

The amount of garbage retained in the raw barrier depends on the gap between the trash barriers; The size of these slots is based on the nature and volume of waste in wastewater. Choosing the right size will help the waste to be maintained optimally without much affecting the flow. Therefore, although the structure & the principle of operation is very simple; But the trash is an important device that must be in the wastewater treatment system.

We often encounter raw barriers installed in lakes, ditches and dams.