The concept of redox electrolyte and contained in everyday life and industry. Combustion reaction and metal perkaratan merupakn example redox reactions that occur in our daily lives. In our bodies contained various kinds of electrolytes, in which redox reactions take place therein, namely in the metabolism and conductivity signals by nerve cells. Aki and various types of batteries using redox reactions as a source of electricity. The battery consists of an oxidizing and a reducing agent and an electrolyte. Aki, for example consist of metal lead (Pb) as the anode, the oxidation of lead (Pbo2) as cathode, and sulfuric acid as the electrolyte. Dissociation reaction by microorganisms is also a redox reaction. Well, on this occasion we discuss the use of the concept of redox and electrolytes in wastewater treatment is activated sludge method.
Have you ever watched the river water in the village or in the forest? Generally there river water can be used for domestic purposes - such a day to wash, to bathe, even for drinking water. Not so with urban or regional area industri.Air river was often dirty and smells. It happened karenabanyaknya garbage or waste discharged into waterways and eventually into the rivers. In developed countries, water must be treated before it flowed into the river, so the river stays clean and can be used for recreation.
One kind of dirty waste water is organic waste, ie waste which is the remains of living beings. Such waste can come from household and industry. Organic waste can be processed by utilizing the degrading action of bacteria, called aerobic bacteria. Dirty water (Sewage) contain various kinds of wastes, such as organic materials, sludge, oil, oil, pathogenic bacteria, viruses, salts, pesticides, detergents, heavy metals, and a variety of plastic waste. Therefore, the dirty water must be processed to reduce as much as possible these wastes.
Various parameters used to describe the state of waste water. For example, turbidity, suspended solids, dissolved solids content, similarity (pH),
the amount of dissolved oxygen (DO = Dissolved oxygen), and biochemical oxygen demand (BOD = biochemical oxygen demand).
Do is a measure of the amount of dissolved oxygen. Dissolved oxygen can be started from the air or the water plant photosynthesis hasi. This dissolved oxygen needed by animals - animals water for breathing. Animals - animals could survive if water dissolved oxygen (DO) not less than 5 ppm. Dissolved oxygen is also used by aerobic bacteria in deciphering organic waste (oxygen-demanding materialist) contained in the water. Many of oxygen required by aerobic bacteria to decompose waste water in a hypothetical organi-called BOD. The more organic waste in water, the greater the BOD value. In contrast, dissolved oxygen (DO) will be smaller.
Wastewater treatment can be divided into three stages, namely primary stage, secondary stage, and tertiary stages. Treatment of primary stage intended to separate the garbage that is not soluble in water so as not to experience deposition (sedimentation). Secondary stage is intended to remove BOD, by the way mengoksidasinya. Furthermore, the tertiary stage is intended to eliminate the waste that still exist, such as toxic organic waste, heavy metals, and bacteria. Tertiary stage processing performed for the water treatment industry. In the next section will discuss one way of processing waste water in the secondary phase, namely how to activated sludge (actived sluge prosess).
Activated sludge is a mud-rich with aerobic bacteria, the bacteria which can outline of organic waste biodegradation by experiencing (oxygen-demanding materials).
Of aerobic bacteria convert organic waste into biomass in water of CO2 gas, while organic nitrogen is converted into ammonium and nitrate, organic phosphorus is converted into phosphate.
Biomass degradation products remain in the aeration tank to the bacteria through a period of rapid growth (long phase). After that will experience the flocculation forming an easier mengendap.Dari solids settling tank, some mud thrown, others circulated into the aeration tank. Combination of bacteria in high concentrations and hunger (in the mud which is circulated) by the amount of nutrients that many (in dirty water), allowing the decomposition to take place quickly. Decomposition by activated sludge method requires only a few hours, far faster than lenih similar decomposition occurs naturally in a ditch or river water.
