The process of sewage treatment refers to a number of procedures involved in eliminating the contamination of water with solid waste. These materials are either discharged directly into the environment, or as a by-product of any pre-existing processing of this material. In most developed countries, such wastes are discharged directly into the environment without any treatment at all. Such “discharged” wastes are also known as solid waste.
Domestic household waste water is generally treated before it is discharged into the environment. For example, if a homeowner produces and uses a compost pile on their property for organic gardening, they have been doing the process of “composting” household waste water. Household waste water is usually combined with anaerobic bacteria, usually bacteria found in a home swimming pool. These bacteria kill most of the dissolved contaminants and allow water to pass through a series of filters before it is discharged into the environment.
However, there are other forms of “solid waste” which are not treated at all. These “waste” materials are referred to as ‘grey water’. Grey water contains microscopic solids such as leaves, sticks, and grass clippings that are not harmful to human health, but which are potentially harmful to wildlife. The reason that such waste is not treated before it enters into the natural flow of water is because it would become too diluted for the process of “natural” water distribution. In addition, it would contain harmful chemicals like herbicides, pesticides, and even sewage sludge. There are several types of household waste water filtration systems which are designed to remove these contaminants and make water safe for drinking or bathing.
Residential waste water treatment systems are designed to treat household waste water by first treating it with chemicals that kill bacteria, allowing the water to pass through the system and then allowing it to drain naturally. This is done by the use of a sump pump or “bucket head” pump. It is important to note, however, that these systems only treat water in the immediate area where it is being discharged into the environment and do not treat the entire amount of water which might be discharged into the environment. For this reason, they are not suitable for all types of waste water distribution systems, including those for agricultural production.
Commercial waste water treatment is commonly combined with “softening” methods to make the water more manageable. Some examples of softening methods include deionization and reverse osmosis. Deionization uses chemicals, while reverse osmosis uses activated granular carbon, or RO (ionic anhydride) to break up wastewater. Softening methods are commonly used on water which is discharged into municipal treatment facilities. Commercial treatment facilities, such as treatment plants, which provide water for industrial operations or industrial plants, generally have such processes included in their systems as part of a complete set of methods.
However, for industrial use, water from agricultural operations must be treated both in the field and onsite. Some of this water is so contaminated that it cannot be treated onsite, while the rest can be treated onsite using “hard water softeners.” Industrial water treatment includes mechanical filtration, distillation, or carbon filtration. Mechanical filtration is usually combined with other treatment techniques such as carbon or ceramic. membranes, or ion exchange in order to remove any impurities present which could cause problems for plant operations or for humans who drink the water.