现代电厂大多脱硫装置为石灰石/石膏湿法烟气脱硫装置，脱硫循环泵被称为“脱硫装置运转的心脏”，保送介质为石膏固相物以及硫酸、盐酸等酸性物质，会构成脱硫循环泵泵壳、叶轮等部位呈现严重的气蚀、磨损和腐蚀等现象，影响循环泵的运用寿命及运转效率，要挟机组的安全运转。同时，浆液循环泵又是脱硫系统的耗能大户，一台全年不连续运转的400KW浆液泵每年耗电量高达二百多万度，所以对循环泵正确的中止维护和维修，为企业的增收节支奠定了基础。

1、叶轮、泵壳等部位表面的凹坑、粗糙增大了过流时的阻力。    2、叶片缺口会产生了大量的涡流，流量降落，消耗了能量。    3、叶轮和泵壳磨损构成泵口环间隙变大，泵的损失变大。   以上缘由招致的能量多消耗高达6-7%,以400KW的浆液泵为例，每年每台循环泵将多消耗电约18万度。由于浆液泵所处的工况极端恶劣，普通运转一到两年叶轮就需求改换。直径700mm的叶轮、耐磨环、侧板等易磨损件进口费用为70万元左右，国产备件也需求30万元左右，维护费用相当高。所以进步循环泵效率，改进维修技术关于电厂降低用电，节约维修本钱有很大的意义。

In most modern power plants, the desulfurization installation is limestone / gypsum wet flue gas desulfurization installation. The desulfurization circulating pump is called "the heart of desulfurization installation and operation". The guarantee medium is gypsum solid phase, sulfuric acid, hydrochloric acid and other acidic substances, which will cause serious cavitation, wear and corrosion in the pump shell, impeller and other parts of the desulfurization circulating pump, affecting the service life and operation efficiency of the circulating pump , threatening the safe operation of the unit. At the same time, the slurry circulating pump is also a major energy consumer of the desulfurization system. The annual power consumption of a 400KW slurry pump that is not continuously operated throughout the year is up to more than 2 million degrees. Therefore, the correct stop of maintenance and repair of the circulating pump has laid the foundation for the increase of revenue and saving of the enterprise.

1. The surface pits and roughness of impellers and pump casings increase the flow resistance.

2. There will be a lot of eddy current in the blade gap, the flow will fall, and the energy will be consumed.

3. The wear of impeller and pump shell results in the increase of the gap between pump port ring and the loss of pump.

The energy consumption caused by the above reasons is as high as 6-7%. Taking the 400KW slurry pump as an example, each circulating pump will consume about 180000 degrees more power every year. Because the working condition of the slurry pump is extremely bad, the impeller needs to be changed after one to two years of normal operation. The import cost of 700 mm diameter impeller, wear-resistant ring, side plate and other easily worn parts is about 700000 yuan, and the domestic spare parts are also required about 300000 yuan, so the maintenance cost is quite high. Therefore, it is of great significance to improve the efficiency of circulating pump and improve maintenance technology for reducing power consumption and saving maintenance cost.