What are the main factors affecting the operation of the heat exchanger?
Whatare the main factors affecting the operation of the heat exchanger?
Since the emergence of heat exchangers inthe 20th century, heat exchangers have a history of nearly
100 years. The formsof heat exchangers are becoming more and more abundant. Heat exchangers are
used in factories, hotels, restaurants, officebuildings, and entertainment venues. The entertainment venues
have been widelyused.
Figure 1 Chiller
Heat exchangers are used in the industrialfield. In the industrial water consumption, cooling water
accounts for morethan 60% of the total water. However, the cooling water in the circulatingsystem, due to
the increase in water temperature, the change of water flowspeed, and the evaporation of water, Concen-
tration of inorganic ions andorganic substances, cooling towers and pools exposed to sunlight, wind and
rain, dust and debris, as well as equipment structure and materials, etc., areprone to a large number of
microorganisms. Equipment corrosion and deposits, aswell as the resulting slime, dirt and other problems
that block pipelines, evenshut down equipment and cause economic losses.
Figure 2 Blocked pipe
Figure 3 Scaling on theinner wall of the pipe
Figure 4 Scaling on theouter wall of the pipeline
According to observation and research, morethan 90% of ordinary shell and tube heat exchangers have
varying degrees ofscaling problems. From the heat transfer rate equation Q=KS△tm, it can be seen that the
main factors that affect the heattransfer effect of the heat exchanger are: heat transfer coefficient K, heat
transfer area S and average temperature difference △t.The heat transfer area S decreases, which causes the
heat transfer performanceto deteriorate, and the heat transfer efficiency decreases. The averagedecrease
rate can reach more than 30%. In addition to directly causing energyloss, it will also lead to a reduction in
the operating load of productionequipment and affect production capacity. In addition, equipment foul-
ing willalso increase fluid flow resistance, which will increase equipment powerconsumption and periodic
cleaning, which also increases equipment operatingcosts.
After the heat exchanger is fouled, itsthermal resistance increases significantly. At this time, the flow of
therefrigerant (or heating medium) remains unchanged, and the fluid is not easy totransfer the cold (or
heat) to the working fluid side to be exchanged, and itsheat exchange efficiency will be Significantly wor-
se. In this situation, if theprocess still requires the original exchange efficiency to be maintained, it is neces-
sary to increase the inlet water pressure while increasing the flow rateinto the heat exchanger, which
results in a double increase in energyconsumption.
Obviously, this requires very highdescaling ability of the heat exchanger equipment itself. Take the new
hot and cold water units, modular units andother units; 7mm heat transfer tube upgrade, spiral baffle
optimization, andmultiple Shenshi's patented distributors are used in combination, It can effectively
improve the descaling ability of theheat exchanger itself, thereby improving the heat exchange efficiency
of theheat exchanger.
Figure 5 Shen's 130KW shell and tubeheat exchanger
Figure 6 Inner tube wall
Figure 7 Shenshi'spatented design-distributor
Hangzhou Shenshi's newgeneration of shell and tube heat exchangers have good performance, safe
use,long service life, small size and high cost performance. They are widely usedin micro-channel heat