The non-invasive and visual characteristics of electrical resistance tomography （ERT） technology have unique advantages in pipe slurry concentration detection. As the core of ERT technology，the choice of imaging algorithm has a great impact on the detection level. LBP algorithm，Newton-Raphson iterative algorithm，and Landweber iterative algorithm are used to inversely image the three pipe slurry flow regimes，and the applicability of the three algorithms is quantitatively evaluated from three indicators including the imaging accuracy，imaging speed and anti-noise ability. The calculation results show that the LBP algorithm has the fastest imaging speed and the strongest anti-noise ability；the Newton-Raphson algorithm has the highest imaging accuracy. The real-time imaging requirements determine which algorithm shall be chosen.