Spiral Plate Heat Exchanger

Spiral plate heat exchangers are highly efficient heat exchange equipment suitable for heat transfer between steam-gas, steam-liquid, and liquid-liquid. They are applicable in industries such as chemicals, petrochemicals, solvents, food processing, light industry, textiles, metallurgy, rolling steel, and coking. They can be classified into non-detachable (Type I) spiral plate heat exchangers and detachable (Type II, III) spiral plate heat exchangers based on their structural forms.

The spiral plate heat exchanger, proven by years of practical use, is indeed an efficient stainless steel heat exchanger. It is suitable for applications in various industries such as chemicals, petrochemicals, solvents, food, light industry, textiles, metallurgy, rolling steel, and coking. This heat exchanger, incorporating contemporary technology, is a liquid-liquid and vapor-water heat exchanger manufactured through unique optimized design. The product's structure and process adhere to the standards of Sweden's "Alfa Laval" company, with the spiral plate end face using folded edge argon arc welding, and the "top distance column" special process for capacitive storage contactors, enhancing both intrinsic and external quality, earning recognition from "Baosteel."

The non-separable spiral plate heat exchanger is designed according to the form of non-separable spiral plate heat exchangers as specified in the JB/TQ724-89 standard. It features simple manufacturing, low cost, compact size, and good heat transfer performance. However, it also has its drawbacks, such as the inability to be mechanically cleaned and difficulty in maintenance when damaged. The selector should choose the specific equipment based on the actual situation of the project for effective operation.

Spiral plate heat exchanger structure and performance:

1. This equipment is suitable for liquid-liquid, gas-gas, and gas-liquid heat transfer, applicable to steam condensation and liquid evaporation heat transfer in industries such as chemicals, petroleum, machinery, electricity, light industry, and textiles.

2. This equipment is formed from two steel plates rolled into two even spiral channels. The two heat transfer cutoffs allow for full countercurrent flow, suitable for heat transfer with small temperature differences. It facilitates the recovery of low-temperature heat sources and enables accurate control of the outlet temperature.

3. The outlet on the housing is a tangential design, featuring low local resistance. The helical channel has a uniform curvature, resulting in minimal flow redirection within the equipment, which in turn leads to reduced overall resistance. Consequently, the design flow rate can be increased, endowing it with superior heat transfer capabilities.

4. The ends of the helical channel are welded and sealed, offering excellent sealing performance and a reliable structure.

5. Difficult to repair, especially when issues arise with internal plates, which can be extremely challenging to fix. Some manufacturers remove all the welds at both ends of the equipment, flatten the plates for re-welding, and then roll them back. However, this process consumes an excessive amount of labor. It is crucial to select spiral plate heat exchangers with effective corrosion resistance.

6. Not suitable for mechanical cleaning; production practice has proven that spiral plate heat exchangers are less prone to clogging compared to conventional tube bundle heat exchangers. Particularly, suspended particles like silt and small shells are not easily deposited within the spiral channels. The reasons for this include: one, the single-channel design of the exchanger ensures that as soon as a sediment forms, the circulating flow elevates to flush it away; two, the spiral channels have no dead corners, making it easy for impurities to be flushed out.

7. Due to the presence of fixed-distance columns supporting the spiral channels, there must be no fibrous impurities (cotton yarn, straw sticks, leaves, etc.) entering the heat exchanger.

Maintain strict control of the cooling water outlet temperature below the scaling temperature.

9. The common cleaning methods include steam blowing and alkaline washing. The steam should be blown into the inlet, expelling impurities from the equipment. Many users believe this to be an effective approach.

Detachable Spiral Plate Heat Exchangers (Type II, Type III)

The structural principle is essentially the same as that of a non-detachable heat exchanger, but the channels can be opened for cleaning, with both ends sealed with flanged heads. Particularly suitable for liquid-liquid exchanges involving sticky or sedimentary liquids, as well as gas-liquid and steam condensation. Due to the need for additional components like flanged heads and gaskets, the equipment cost is slightly higher than that of a non-detachable heat exchanger.