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Anonymous users2024-02-07Pickling to remove scale: A cleaning solution composed of inorganic acids or organic acids and appropriate corrosion inhibitors is used to dissolve scale. The pickling method is suitable for the cleaning of strong alkali and weak acid scales, such as carbonate, phosphate, silicate scale, etc. However, for phosphate, because the solubility of calcium sulfate is very small, it is not advisable to clean phosphate scale with sulfuric acid solution, and hydrochloric acid or nitric acid should be used.
When pickling silicate scale, hydrofluoric acid solution or hydrochloric acid solution containing sodium fluoride should be used.
b Alkaline cleaning to remove scale At a certain temperature, use alkaline cleaning solution to clean scale. For example, with sodium hydroxide.
Aqueous solution dissolves calcium sulfate scale:
CAS04+2NaOH Ca(OH)2+Na2S04 Because calcium sulfate is a strong salt, it cannot be dissolved in acid.
For calcium sulfate and calcium carbonate.
The mixed scale should be cleaned alternately with acid and alkali to achieve a good effect.
Caustic washing is also suitable for cleaning silica scale, because the concentrated strong alkaline solution can dissolve silica.
SI02+2NAOH NA2SI03+H20C uses mechanical methods to remove limescale.
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Anonymous users2024-02-06Installation of water treatment equipment to prevent limescale 1361700660** Boiler water treatment equipment.
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Anonymous users2024-02-05There are special descalers for sale, and it is better to buy ready-made ones if you can't grasp the liquid yourself.
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Anonymous users2024-02-04Utilize neutralization reactions.
Go and buy pickling paste yourself, it's very useful.
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Anonymous users2024-02-03For CaSO4 contained in boiler scale, it can be removed by first treating it with NaHCO3 container and then using acid. Here's the full analysis:
1. NaHCO3 liquid treatment.
CaSO4 is one of the main components in hard water, and it is prone to crystallization and scale formation. The NaHCO3 container can reduce CaSO4 to produce soluble Ca(HCO3)2. This more soluble compound can protect boiler equipment by reducing or preventing the formation of scale.
2. Select the appropriate acid for removal.
When using acid to remove scale from a boiler, it is necessary to select the appropriate acid for the ashwager. Because CaSO4 is a relatively difficult compound to dissolve, it is generally possible to react with CaSO4 to form soluble compounds using strong acids such as hydrochloric acid (HCl) or nitric acid (HNO3). Since acids are corrosive, safety should be taken when operating.
3. Pay attention to the neutralization reaction between acid and alkali.
In the process of boiler scale removal with acid, it is necessary to pay attention to the neutralization reaction of acid and alkali. Since the NaHCO3 container is alkaline, it may be removed with acids, resulting in an acid-base reaction that produces carbon dioxide gas and salts. Such a reaction will increase the generation of scale and changes in water quality, so it is necessary to carry out appropriate acid-base neutralization and discharge treatment after treatment.
4. Ensure the safety of operation.
Dealing with boiler scale requires attention to operational safety. Pay attention to personal protection when using acid to avoid acid splashing ** or getting into your eyes. At the same time, the relevant operating procedures and safety operation requirements should be strictly adhered to during the operation.
To sum up, for CaSO4 contained in boiler scale, it can be treated with NaHCO3 container solution to reduce the formation of scale, and then removed with appropriate acid. This treatment method can reduce the scale accumulation of boiler equipment and improve the heat transfer efficiency and working life of the boiler. In the treatment process, it is necessary to pay attention to the safety of operation, reasonably control the amount of acid and alkali, and make appropriate adjustments and discharge treatment of the treated water quality.
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Anonymous users2024-02-021.Calcium sulfate is a slightly soluble substance, whereas calcium carbonate.
It is a refractory substance, solubility.
It is relatively small, so according to the theory of the age or radical ion reaction it is possible to generate more insoluble masses of substances that are more insoluble.
co3 2- =caco3
caco3 + 2h+ =h2o + ca2+ +co2
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Anonymous users2024-02-01A. According to the precipitation transformation, it can be seen that calcium sulfate can be converted into calcium carbonate precipitation, indicating that the solubility of CaCO3 is less than that of CaSO4, so A is correct;
b. The essence of precipitation transformation is the movement of precipitation-dissolution equilibrium to the transformation of more insoluble substances, so B is correct;
c. The essence of precipitation transformation is to realize precipitation transformation according to the solubility of the substance, which is related to the solubility of the substance, so C is wrong;
D. In the precipitation conversion from CaSO4 to CaCO3, both calcium sulfate and calcium carbonate precipitates have precipitation-dissolution equilibrium in solution, and there are two precipitate-dissolution equilibriums, so D is correct;
Therefore, C
Boiler shutdown maintenance method.
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The dosing treatment in the pot is used as a supplementary treatment for boiler make-up water, condensate, and generated return water treatment. Its function is to make the scaling substances brought into the boiler with the feed water react with the added agent to generate suspended particles, which are in a dispersed state, and are added to the boiler blowdown and discharged into the pot through the dosing device, or make it exist in the boiler water in a dissolved state, and will not be deposited on the boiler tube wall, so as to achieve the purpose of scale prevention. >>>More
It is recommended to use a bag filter, the working mechanism is that the dusty flue gas passes through the filter material, and the dust particles are filtered down, and the filter material mainly relies on inertial collision to capture coarse-grained dust, and the fine-grained dust is mainly collected by diffusion and screening. The dust layer of the filter material also has a certain filtering effect. >>>More
According to the long-term practice of Wenzhou Nanxing Environmental Protection Company, which specializes in boiler maintenance, it has been proved that during the operation of the heat transfer oil boiler, carbon deposits and scaling will be generated due to: >>>More