The continuum self-consistent-field theory (SCFT) is employed to study the adsorption of bi-disperse flexible polyelectrolytes (PEs) on two charged parallel columns. The effects of the bi-dispersity in terms of the average volume fractions and chain lengths of two kinds of chemically identical charged homo-polymers on the total amount of absorbed PE chains, the degree of charge compensation, and the total amount of the bridging chain conformation are investigated by numerically solving the SCF equations. The numerical study reveals that the longer PE chains are more effective than the shorter ones in charge compensating the opposite surface charges. The larger the relative chain length difference is, the more effective the longer PE chains in charge compensating the surface charges will be. The numerical results show different degrees of sensitivity of PE-adsorption to the screening-reduced salt effect for the constituents of the bi-disperse PE system. Moreover, how the dielectric contrast of the non-polar PE chains, the charged objects with respect to the polar solvent molecules impact the adsorption behaviors of mono-disperse PE chains is also examined. (C) 2013 Elsevier Ltd. All rights reserved.