What are the advantages and disadvantages of anode acid coolers and acid coolers (plate heat exchangers) respectively?

At present, anodic protection technology in China is becoming increasingly mature, and its use is recommended. 5 years ago, domestic anodic protection technology was not mature, so plate coolers were recommended. Anodic protection requires more space, has a slightly lower heat transfer coefficient, and necessitates a larger heat transfer area ； Plate heat exchangers occupy less space and have high heat transfer efficiency, but they have high operating costs, and the gaskets used are expensive. The initial investment costs for the two are similar, but anodic protection has an advantage in terms of subsequent investments. In terms of performance, anodic protection virtually requires no maintenance and is less prone to acid leakage.

I work with high-heat-exchange equipment, and I think plate exchangers are better. If the rubber pad is of good quality, it does not need to be replaced frequently. Plate heat exchangers require higher initial investment, but they offer much higher thermal efficiency.

Each has its advantages, but Yang Bao is still the preferred option – in the event of acid leakage, treatment with Yang Bao is faster; whereas replacing the plate requires time-consuming disassembly and reinstallation

Especially in areas with concentrated acid, if one gasket leaks acid, and it has to be removed and reinstalled once, basically the entire set of rubber gaskets becomes unusable. How much does a set of gaskets cost? The imported ones cost over 200,000, and the more advanced ones cost over 500,000 – and that’s just for the gaskets! If a part of the heat exchange plate corrodes, spare parts have to be purchased, and they cost tens of thousands of dollars each. The quality of domestically produced plate heat exchangers for concentrated acids is even worse; the gaskets used in such exchangers made in China are completely unsuitable for use – they become unusable in less than half a year, resulting in costs of over 100,000 yuan. Fortunately, the anodic protection performed well, holding its ground for 5 months; the acid temperature during operation increased by nearly 10 degrees. I swear not to use domestic concentrated acid rubber gaskets anymore; if the opportunity arises, I will replace the plates with anodic protection.

In my opinion, the biggest difference is that plate heat exchangers save space by more than one-third! The cost of dealing with clogged circulating water in Yangbao is almost zero, whereas each time a plate heat exchanger is removed, it’s generally necessary to replace the gaskets, at a cost of tens of thousands or even hundreds of thousands of yuan; if it’s not installed properly the first time, more problems will arise... In my opinion: 1. If the acid temperature is high, such as 100 degrees, then Yangbao is the only option. 2. If there are no restrictions regarding space requirements, it’s better to choose Yangbao. 3. If the circulating water quality is poor or scaling often occurs, Yangbao is still the better choice.

Plate heat exchangers have high heat exchange efficiency and occupy a small area, but their equipment maintenance is complicated and the repair costs are high. The heat exchange efficiency is lower during the relative anodic protection period, and it requires more space for the same heat exchange area. However, its advantages lie in the simplicity of cleaning and maintenance; moreover, the corrosion caused by changes in acid temperature and concentration can be measured and controlled (thanks to instruments), allowing for the prevention of production safety hazards such as acid leaks. Currently, the cost for anodically protected heat exchangers is around 1,000 RMB per square meter of heat dissipation area. In terms of cost, the difference between the two is not significant. However, from a maintenance perspective, anodic protection has significant advantages; under normal conditions and considering actual usage, the electrodes need to be replaced only after a long time, which results in much lower maintenance costs compared to gaskets and heat exchange plates. All the absorption units in the three sulfuric acid plants at our facility use anodic protection heat exchangers, which have proven to be very effective.

Although anodic protection acid coolers are excellent, poor control of their parameters can **shorten their service life.