ZGB200 Desulfurization Pump Ceramic Coating Upgrade: Anticorrosion Solution for Higher Chloride Concentration

In wet flue gas desulfurization (FGD) systems, the ZGB200 desulfurization pump acts as a core circulating pump for gypsum slurry. With increasingly strict environmental policies and unstable coal quality, the chloride ion content in desulfurization slurry keeps rising. Many thermal power plants face chloride concentrations exceeding 20,000 ppm, and some extreme working conditions even reach 60,000 ppm. Traditional high-chromium alloy wet parts suffer from pitting corrosion, erosion damage, and rapid performance degradation. Therefore, ceramic coating upgrade has become the most reliable anti-corrosion solution for ZGB200 desulfurization pumps.

1. Corrosion Pain Points of ZGB200 Pump Under High Chloride Conditions

The ZGB series is a heavy-duty double-casing desulfurization pump. Its original high-chromium cast iron materials cannot adapt to continuously increasing chloride concentration. Three typical failure problems often occur:

• Chloride pitting corrosion: Chloride ions penetrate the metal passivation film to form localized corrosion pits, accelerating electrochemical corrosion at an exponential rate.

• Erosion-corrosion coupling damage: The solid content of gypsum slurry ranges from 15% to 30%. Solid particles continuously scour the inner wall, destroying the corrosion protective layer and aggravating material loss.

• Material limitation: Ordinary high-chromium alloys can only resist chloride ions below 15,000 ppm. Once exceeded, leakage and efficiency decline will occur within 3 to 6 months.

2. Silicon Carbide Ceramic Coating Upgrade Technology

To adapt to future high-chloride working conditions, XO Slurry Pump upgrades the ZGB200 desulfurization pump with silicon carbide ceramic coating. This modified composite ceramic material effectively solves corrosion and abrasion problems without changing the original pump hydraulic structure.

2.1 Core Coating Material Properties

2.2 Professional Construction Process

The ceramic coating construction is specially optimized for ZGB200 pump casing and impeller:

1. Surface blasting treatment up to Sa2.5 grade to completely remove oxide layers;

2. Anti-corrosion primer coating to enhance adhesion between metal and ceramic layer;

3. Thickened silicon carbide surface coating (3-5 mm); key scouring parts are increased to 6 mm;

4. High-temperature curing to eliminate internal stress and improve coating compactness.

3. Advantages of Ceramic Coating Upgrade for Future Working Conditions

1. Long service life: The service cycle of ZGB200 wet parts is extended to 3-4 years, reducing 80% of replacement frequency.

2. Ultra-high chloride resistance: Stably withstand 60,000 ppm chloride concentration, fully adapting to increasingly harsh coal quality.

3. Low operation cost: Reduce unplanned downtime; annual maintenance cost is decreased by 40% to 50%.

4. No performance loss: The original hydraulic flow channel remains unchanged; flow rate and head will not decay after coating upgrading.

4. Conclusion

With the continuous increase of chloride content in thermal power desulfurization slurry, traditional alloy materials can no longer meet long-term operation requirements. The ZGB200 desulfurization pump ceramic coating upgrade provides an efficient and economical anti-corrosion solution for high-chloride working conditions. By adopting silicon carbide composite ceramic technology, the pump achieves excellent anti-corrosion and anti-abrasion performance, realizing stable and low-cost operation in the long term.

As a professional industrial pump manufacturer, XO Slurry Pump（www.xoslurrypump.com） provides customized ceramic coating upgrade services for the full ZGB pump series. If you need technical support for high-chloride desulfurization pumps, please contact our engineering team for a complete solution.