chemical impact corrosion abrasion wear resistant repairing and protecting
Wet flue gas desulfurization environmental protection technology (FGD),because of its features of high desulfurization rate,
wide coal quality application scope,mature technology,long stable operation cycle,small load change influence,large flue gas treatment ability,
is widely used in each large,medium-sized coal-fired power plants,become the dominant technology of flue gas desulfurization in the thermal
power plants at home and abroad,But this technology also has the features of strong medium corrosivity,high flue gas temperature,big SO2
absorption liquid solid content,strong wear resistance,large equipment corrosion resistant area,high quality requirement of the construction
technology,difficult maintenance of corrosion resistant failure.So the equipment corrosion control is one of the key problems of affecting
device for long-term safe operation.
Wet flue gas desulfurization absorption tower,chimney inner barrel anti corrosion material selection must consider
the following aspects:
1. meet the anti corrosion requirements under the conditions of complex chemical environment: the chemical environment is complex in the chimney,
flue gas acid content is very high,formative congelation on the lining surface has very strong corrodibility for most of building materials,
so requires the lining material to have strong acid corrosion resistance;
2.temperature resistance requirements: The temperature difference of flue gas is big,the temperature of flue gas is between 40- 80 degree after
wet desulfurization,under the working condition of the desulfurization system maintenance or not run but the unit operation,
the flue gas temperature inside the chimney is between 130-150 degree,so requires the lining to have the ability of resisting temperature
difference, in the environment of frequent change in temperature is not cracking and durable.
3. the wear resistant performance is good: the flue gas contains a large number of dust,while under the effect of corrosive medium,
the actual situation of wear may be more obvious,so request anti corrosive material with good abrasion resistance.
4.has certain flexural resistance performance: due to the high altitude characteristics of some chimneys,including the movement of the earth itself,
earthquake and wind action etc conditions,the chimney especially high altitude part may happen to rocking etc.angle deflection or deviation,
and the chimney might happen to some uncontrollable mechanics function etc.in the process of installation and transportation,
so request anti corrosive material with certain flexural resistance performance.
5.has a good bonding strength: corrosion resistant material must have a strong bonding strength, not only refers to the bonding strength of material
itself is higher,but also the bonding strength between material and substrates is high, and required that the material is not easy to produce cracks,
delamination or stripping,with better adhesion and impact strength,to ensure the better corrosion resistance.Usually we require the adhesive strength
of the undercoat material and the steel structure foundation can reach to at least more than 10 mpa.
Construcation application case photo shows:
