Because when water and air come into contact, a part of the gas will be dissolved into the water, which causes the boiler feedwater to dissolve a certain volume of gas. Oxygen is the main corrosive substances in the boiler feed water system, the oxygen in the feed water system should be quickly removed, otherwise it will corrode the boiler feed water system and components, corrosive substances iron oxide will enter the boiler, deposited or attached to the boiler tube wall and heating surface, line into a difficult to dissolve and poor heat transfer of iron scale, corrosive iron scale will cause the pipeline inner wall appeared point of the pits, the coefficient of resistance increases, the pipeline corrosion, and even a pipe burst accident. Pipeline corrosion is severe, and even pipeline leakage accidents.
So from the boiler feed water to remove oxygen, is to prevent boiler corrosion of effective measures, boiler feed water deoxidizing method has a variety of boiler deoxidizing method, now the boiler deoxidizing mainly by the thermal deoxidizing and chemical deoxidizing mainly.
First, thermal deoxygenation: thermal deoxygenation principle is to heat the water to the corresponding pressure under the saturation temperature (generally reach the boiling point), the partial pressure of steam close to the full pressure on the water surface, the partial pressure of oxygen dissolved in the water is close to zero, so that the oxygen precipitation, and then the water surface oxygen exclusion, so as to ensure that the oxygen content of the water supply to meet the requirements of water quality standards.
But steam consumption, generally need to consume 18-20% of the boiler steam production; temperature control range is narrow, only about 2 ℃, load adaptability is poor, in actual operation, due to frequent changes in the boiler heat load, management and operation level is not high, will lead to boiler thermal deoxidizer effective operation of the necessary conditions can not be met, deoxidizing efficiency and deoxidizing effect is not satisfactory and so on.
Second, chemical deoxygenation: chemical deoxygenation is also a commonly used deoxygenation measures, commonly used deoxygenation reactant is hydrazine, hydrazine in alkaline aqueous solution is a very strong reductant, can be the dissolved oxygen in water reduction, the reactant produces N2 and H2O on the thermal system and equipment without any harm, away from the dark deoxygenation is used as a thermal deoxidizing auxiliary measures to achieve the complete removal of residual oxygen in the water, and does not Increase the salt content of boiler water.
However, hydrazine is a toxic substance, and is suspected of carcinogenic effect, hydrazine has a strong volatile, flammable, explosive, and very easy to be inhaled by the human body, affecting the health of the operator can not be used for domestic boilers; hydrazine excess should be appropriate, too large an amount of excess ammonia may be incomplete reaction with the people to the water vapor. Many domestic power plants still use hydrazine deoxidizer, but Europe, the United States, Japan and other countries have abandoned the hydrazine, the development and application of new organic deoxidizers, and at the same time, the hydrazine as a highly toxic banned products.
Kerun new deoxidizer:
This product belongs to the latest generation of high-efficiency deoxidizers, which is mainly used for deoxidizing boiler feed water and protecting boilers and other thermal equipments when they are out of service. It can be used alone or in conjunction with other agents, and is suitable for boiler systems with operating pressure not more than 17MPa.
I. Physical and chemical properties:
▲Appearance: transparent and colorless
▲Water solubility: 100%
▲Freezing point: ≤0℃
▲Density: 1.05±0.05g/cm³(at 20℃)
▲pH value: ≥7(at 20℃)
Second, product advantages.
(1) Alternative: the preferred agent to replace hydrazine, high deoxidation efficiency and stable performance.
(2) Extend the service life of equipment: it can effectively eliminate the residual dissolved oxygen after thermal deoxidation, eliminate the risk of dissolved oxygen corrosion, strengthen the passivation effect of feed water and steam condensate system, the overall protection of the thermal system, and extend the service life of equipment.
(3) Influence: no introduction of soluble solids, does not affect the hydrogen conductivity of feed water and steam.
(4) Safety: non-toxic, non-explosive, reduce the risk of employee chemical hazards, more environmentally friendly.
(5) Applicability: Applicable whether or not condensate fine treatment device is set up in the system.