Reading guidance：With the continuous development of sewage treatment plants, a large number of sludge followed, can find cheap is a research hot spot and focus. 1.Key index of sludge (1) moisture content: wet sludge re

    With the continuous development of sewage treatment plants, a large number of sludge followed, can find cheap is a research hot spot and focus.
1. Key index of sludge
  (1) moisture content: wet sludge reduction key. (2) bacteria and virus inactivation rate, poisonous and harmful substance content: harmless important symbol, is to determine whether the agricultural conditions, and is suitable for building applications. (3) heavy metal content of heavy metals and existing state of the agricultural risk and whether it is suitable for the garden with earth. (4) shear stress index: decide whether as garbage soil, building soil, and the restoration of mud. (5) organic matter, nutrient content: the decision is used as fertilizer and fuel accessories. The index is the sludge treatment can be safe reuse of nature.
 2. The application of calcium oxide in the process of sludge dehydration
   Sludge and calcium oxide dehydration process simple, low energy consumption. Specific application is adding calcium oxide by pH and temperature increased to achieve sludge sterilization; or by the addition of calcium oxide and other substances (such as fly ash, cement, calcium carbonate, such as) the sludge curing effect to meet the requirements of the process of sludge landfill. In addition, the processing in the process of choosing suitable mixed conditions can effectively change the sludge properties, is composed of dense, thick became loose, good fluidity, easy to storage and transportation of materials.
   3. The dehydration and disinfect mechanism of calcium oxide in the process of sludge disposal
 The sludge and calcium oxide can be mixed evenly, and the content of calcium oxide and sludge can be as follows:
  1 kgcao 0.32 kgH2O, 1.32 kgca (OH) 2 1 177 kJ according to this reaction, each adding 1 kg of calcium oxide 0.32 kg of water is combined with a calcium hydroxide, the generated heat can be evaporated to about 0.5 kg of water. So a portion of the water treatment sludge are combined into solid calcium hydroxide and a part of evaporated.
   In the subsequent reaction is to calcium hydroxide as subject and sludge in the complex components occur a series of reaction, and generate ammonia (ammonium hydroxide). The above process, calcium oxide of sludge dehydration effect is not very significant and due to calcium hydroxide generated will lead to solid volume fraction increases. Usually alkali stabilization technique is to rely on calcium oxide reacts with water to evaporation of water, and disinfection, however, in calcium oxide processing sludge system in calcium oxide's role here is just beginning. That is, calcium oxide dehydration is mainly manifested in the disinfection mechanism of calcium hydroxide and of cell wall and a gelatinous layer crack.
  4. The crack of the calcium oxide in the lock control water of the flocculant
  Flocculant water lock function: flocculant with positive (negative) groups and some of the water with a negative (positive) and difficult to separate particles or particles, reducing its potential, to make it in steady state. The polymerization properties make these particles, called "and" theory of coalescence of the nature of the polymer and the interior moisture lock control. At present domestic sewage treatment factory is the most common type is positively charged, cationic flocculant. At this time due to the addition of calcium oxide, calcium hydroxide forms caused by pH value increased, cationic flocculant will be rapid hydrolysis, the polymer water into free space water.
   5. The crack of calcium oxide on the control of water in the glial cells and cells.
   So far, almost all the research that calcium hydroxide as an antimicrobial agent theory and pH value has a direct relationship, and the calcium hydroxide can steadily and slowly release, pH value also plays an important role can damage the bacterial cell membrane enzyme, changes its chemical structure, resulting in the killing effect on bacteria.
  6. Calcium hydroxide, ammonium hydroxide solution mechanism of cell injury
   Alkali saponification reaction with lipids in the nucleus, and with tissue protein form soluble in aqueous alkaline protein, compound formation has a dual phase solubility, both water-soluble and fat soluble, thus damaging the cell membrane on the skin barrier, and quickly penetrate nuclei and glial structure of each layer organization. Alkali into cells, pH value increased rapidly, so that the formation of alkaline substances with components of the cell of the compound is dissolved more easily. And in alkaline environment conducive to cell membrane lipid emulsion, which led to the destruction of the cell membrane.
    Calcium oxide is added in the sludge treatment can achieve semi dry with low cost and simple process, curing and sterilization, and at the same time improve sludge characteristics so as to be convenient for storage and transportation. Low cost become calcium oxide to be popularized in the very important factors.
  
 
 
 
 
 

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