Some of the inorganic substances commonly found in wastewater are Sulfur, Nitrogen, Phosphorous, and Hydrogen Ions – that have the potential to change the pH of water, compounds that can increase the alkalinity of the wastewater and Chloride.

Phosphorous and Nitrogen are useful to plants as nutrients. But if treated wastewater containing high amounts of these two elements, is discharged into water bodies, then these will feed the growth of alga in those water bodies.

Apart from removing inorganic substances, while design your effluent treatment plant, you also have to consider the dangers posed by toxic compounds. The treatment plant should also be able to handle the heavy metals contained in the influent.

The design of the treatment plant has to incorporate pretreatment stairs satisfying strict pretreatment criteria so as to protect the downstream treatment process from toxic shock.

The biologic treatment process utilizes microorganisms to treat the wastewater. This step of treatment generates a large measure of gases like Carbon Dioxide, Methane, Ammonia, Hydrogen Sulfide and Nitrogen.

To identify whether an aerophilic treatment process is underway or if anaerobiotic microorganisms ar active, the treated wastewater flowing out can be analyzed as to the nature of dissolved gases.

Biological treatment processes normally involve the action of aerophilic microorganisms. For an aerophilous process to run smoothly, wastewater should have sufficient measure of dissolved oxygen. Hence the design of the plant should also incorporate wastewater aeration.