Basic municipal wastewater characteristics can be difficult to understand. Do you truly understand what occurs to your municipal wastewater after you flush the toilet, shower, or wash dishes? Where does it go? What is inside it? How does it affect the natural environment and why should you even care?
These and many more questions should be answered by a knowledgeable professional who deals with municipal wastewater treatment systems. They should explain to you all the necessary characteristics of municipal wastewater treatment plants. You need to be aware of the basic facts. They also need to explain how these characteristics are important to us humans. This is so we can understand why we need to care about them.
One of the most important municipal wastewater characteristics is that it contains both dissolved and insoluble waste particles. Some people may immediately think that solids mean bad things but you would be surprised at how many good things in municipal wastewater can be found in it. Certain characteristics such as the presence of regulated sulfates can help to reduce bacterial growth in wastewater, while the presence of iron and copper can contribute to increasing the pH level and decreasing the acidity level of municipal wastewater.
Another important characteristic is that it contains methane. Yes, methane! However, when it comes to methane it is not a great thing, as this gas acts like a very strong catalyst for biological growth. Although most people will immediately think that we need to burn this gas off and prevent its spread into our groundwater, what they don’t realize is that methane can be combusted in wastewater treatment systems. So, although it is a powerful fuel for oxidation it is not good for combustion.
Finally, one of the most important characteristics of municipal wastewater is that it contains both dissolved and insoluble organic pollutants. These two groups of pollutants generally interact with one another during the transportation of the wastewater through the pipes of the sewage treatment plants. During the discharge of the treated wastewater into the environment, these two groups combine to form different kinds of pollutants, some soluble and some insoluble. So, in addition to providing a valuable service by treating our wastewater, these pollutants play a role in keeping our lakes and streams clean and protected from pollution.
These two groups of inorganic materials tend to combine chemically to form different kinds of organic pollutants, which are then released into the atmosphere. These chemicals have to be removed by either the natural bioporation methods used by plants or the more recently developed biological treatment technologies. Although both of these processes are costly and potentially harmful to the environment, biopurification is becoming a popular choice. By removing these inorganic materials from the wastewater, it allows for the increased utilization of nutrients that are already in the environment.
Many gases, including those produced by the combustion of fossil fuels, are released into the air during the municipal wastewater treatment process. These organic compounds are removed by aerobic (oxygen-requiring) bacteria that are found in the water. But, because these oxygen-requiring bacteria are unable to survive in oxygen-free water, they are effectively killed during the process by anaerobic (oxygen-unfriendly) microbes. The presence of these anaerobic microbes in wastewater has been associated with the increased presence of certain types of cancer in the environment. Other organic compounds that are removed include nitrates, creatine, nitrites and by products of biodegradation of Nitrogenous compounds such as nitrogen, sulphur compounds and ammonia.
Because aerobic (oxygen-requiring) microorganisms are unable to utilize the available oxygen in treated wastewaters, large concentrations of these aerobic organisms are usually necessary to keep the water flowing freely enough to meet the needs of its inhabitants. The presence of these types of organisms also means that they are constantly being exposed to the synthetic organic chemicals and gases that are commonly released into the atmosphere from municipal wastewater treatment plants. These artificial organic materials, often referred to as VOCs, are a considerable cause of damage to the ecosystem. Studies indicate that many VOCs are now present in most major cities throughout the US. Therefore, even if you do not use tap water for your drinking water, it is likely that you are still breathing in some VOC-like molecules.