1.Preface

Air and water, are the main elements consisting life from long time ago to the present time and they have played their vital role in human life continuation and organisms’ life.

Now for continuation of life, we have to think about environment pollutant like industrial and human swage which are the main contaminants of current and underground water and do all requirements in treating them.

The daily used water which will be returned to the environment by human is called human wastewater and if this water is from industrial activities then it is called industrial wastewater.

Sanitary swage is commonly formed from sanitary like Toilets, wash basins, bathrooms, kitchen wastewater and wastewater collector from different cleaning areas.

Properties of these swages are usually the same and it depends on amount or produced swage per head.

Given the existence of pathogenic microbes and infecting natural resources and also possibility of reusing and recycling of treated sewage in agriculture, usually they treat this swage which will be done in two stages:

-          Initial stage contains physical treatment (like: removal of junk granulation, sedimentation and…….)

-          Final stage contains Bio or Biologically (Anaerobic, Aerobic and………).

In sewage treatment, there are different methods which can be used best with putting into consideration the economic factors and climatic condition of that area.

Also, in industrial sewage treatment plants, different methods can be used depending on wastewater qualitative parameters and quantitative quantities and also depending on disposing method.