A multimodal tomography system based on the electrical capacitance and electrostatic sensor arrays is proposed to investigate the effects of particle charging in the pipe on electrical capacitance tomography (ECT). The effect of the charge in the pipe on the detection circuit of ECT is firstly analyzed. Then the simulations are performed to make further investigation on the effect of the charge distribution on ECT. The simulation results indicate that the electrostatic effects on ECT vary with the spatial distribution of the charge in the pipe. The charges near the pipe wall have greater effect on ECT than those in the center of the pipe. The capacitance electrode-pairs near the charge distribution are greatly affected. Experiments are also performed on a pulley rig, which verify the simulation results.