Sewage is mainly liquid waste.

Sewage refers to the wastewater that is produced from various sources such as households, industries, and commercial establishments. It primarily consists of water and various types of waste materials. Here is a detailed explanation of why sewage is mainly liquid waste:

1. Composition:
Sewage is predominantly composed of water, which makes up a significant portion of its content. This water comes from various domestic activities like bathing, washing dishes, and flushing toilets, as well as industrial and commercial processes.

2. Liquid waste:
The majority of the waste materials in sewage are in liquid form. These include dissolved and suspended organic and inorganic substances, such as food waste, detergents, oils, chemicals, and urine. These liquid waste materials are carried along with the water in sewage pipes and drains.

3. Solids in sewage:
While sewage is mainly liquid waste, it also contains a certain amount of solid waste. This solid waste consists of materials that are not easily dissolved or broken down in water. Common examples of solid waste found in sewage include toilet paper, feces, and other human waste, as well as non-biodegradable items that are flushed down toilets or washed down drains.

4. Gaseous waste:
Sewage does contain some gaseous waste, but it is not the main component. Gases such as methane, carbon dioxide, and hydrogen sulfide can be present in sewage due to the decomposition of organic matter. However, these gases are typically produced in smaller quantities compared to the liquid and solid waste components.

5. Mixture of solid and gas:
Although sewage primarily consists of liquid waste, it can also be considered a mixture of solid and gas waste. The solid waste particles are suspended in the liquid component, while the gas waste is present in the form of bubbles or dissolved gases within the liquid.

In conclusion, sewage is mainly composed of liquid waste due to the high water content and the presence of dissolved and suspended waste materials. While it does contain some solid waste and gaseous waste, these components are not as significant as the liquid waste in sewage.