Absorption tower anti corrosion wear abrasion resistant coating application
Wet flue gas desulfurization process is the most mature in technology and the most widely used in the world at present,wet flue gas desulfurization
contacts with the flue gas through circulating liquid to produce the chemical reaction to achieve desulfuration effect,the flue gas which produced by
burning is acidic,acidic material from flue gas dissolved in water to form weak acid.Wet sprinkling reduced the temperature of flue gas,when the flue
gas temperature is below acid dew point,it will appear the acid dew formation phenomenon,congealed acid liquor will absorbed on the absorption tower
inner wall and other parts accessories to cause the equipment corrosion,the main pipeline and equipment of desulfurization system,such as absorption
tower,mist eliminator and pumps etc all need to take measures of corrosion resistant,for the existent corrosion problem inside of absorption tower,it has
already had much more mature corrosion resistant meatures.we use the composite protective coating and pass the actual application,and achieve ideal
anti wear abrasion corrosion resistant effect.
Absorption tower is the core equipment of the wet desulfurization system(FGD),it is made from tower body,support beam,lattice beam,bracket,tray and
piperonyl cyclonene etc.Flue gas contacts with the slurry in the absorption tower and mix to complete desulfurization reaction,this area mainly has abrasion
together with corrosion,the composite protective coating choosed BD407 anti corrosion resistant coating(it is depends on the actual working condition to
choose the BD408 flakes corrosion resistant coating) and BD7053 desulfuration system special anti wear corrosion resistant coating,it will form the outer
layer abrasion resistant and inner layer corrosion resistant composite coating structure,it has wear resistant layer to protect corrosion resistant coating
from erosive wear to cause invalidation,and provide continuous protection for the workpiece,the service life for the whole coating is depends on the
thickness of surface abrasion resistant layer,according to the experience data,when BD7053 desulfurization system special anti wear abrasion resistant
used in the inner of absorption tower,every 1.3mm coating thickness can provide about circannual protection for the absorption tower.
Zhenzhou Xinli Electric Power Co. , Ltd has 5 sets 220 MW heat supply turbine units for business undertaking at present,absorption tower piperonyl
cyclonene is under the condition of serious corrosion and abrasion,use the Xiangyang Hundred Shield composite protective coating to do the protection,
this project tested run in successful on March,2016,go through testing run for 6 months,it has already finished performance tests of continuous 15 days
on Sep.2016,the various index all achieve the standard requirements,we can make sure the desulfuration efficiency be more than 95%,the desulfurization
equipment runs steadily,corrosion resistant condition is good.
1.The construction procedure as follow:
surface treatment:Do coarsening treatment on the pending-repair area, grinding with angle grinder or sand blasting and so on, the surface after coarsening
treatment should be cleaned,the surface after this treatment should be the one coarsening,dry and fresh substrates,should be no greasy dirt and dust.
2.The preparation of anti corrosion resistant protective coating:
First: The preparation of BD407 corrosion resistant repair coating is based on the mixing weight ratio A:B=4:1,then stir and mix them uniformly.
Notice:every time the largest preparation quantity can’t be more than 2Kg,and use it up within 30 min.
Second:Make the well mixed anti corrosion resistant protective coating be blade coating on the pending-construction area of absorption tower piperonyl
cyclonene uniformly,and blade coating for at least 2 times with corrosion resistant protection coating,the whole coating thickness is about 1.5mm.
Third:The curing and detection of anti corrosion protective coating:After the corrosion resistant coating curing,should do electric spark leak-checking detection,electric spark detector voltage should be setted between 1000V and 1500V,the detection area where has no electric discharge phenomena is
compliance region,if there is electric discharge part,we should line out obvious tagged,then do the repairing for this area,the part after repairing after
curing,should do the secondary detection,until that the whole anti corrosion resistant protective coating has no leakage point,we should do the next step
operation after the repairing part curing.
3.The preparation of anti wear abrasion resistant protection coating:
Before wear abrasion resistant protective coating construction,we should confirm that the previous used anti corrosion protective coating has already
been complete curing,should pay attention to doing the protection for already cured corrosion resistant protective coating during the wear resistant
