Grid approximations of the Dirichlet problem are considered in a vertical strip for the semilinear elliptic convection-diffusion equation; for this problem, the nonlinear difference scheme based on the classic approximation of the problem on a piecewise-uniform grid refined in a layer converges ε-uniformly in the uniform norm with the convergence rate order not higher than one.Using the Richardson technique, we construct a nonlinear scheme (the Richardson scheme on nested piecewise-uniform grids) convergent ε-uniformly with the improved convergence rate O(N −2 1 ln 2 N 1 + N −2 2 ), where N 1 + 1 and N 2 + 1 are the numbers of nodes on the axis x 1 and on the unit segment of the axis x 2 , respectively. In order to solve this scheme, we construct iterative schemes of higher accuracy, which are the linearized scheme (the nonlinear term is calculated based on the desired function taken from the previous iteration) and the scheme of the Newton method, as well as truncated variants of iterative schemes convergent at the rate O(N −2 1 ln 2 N 1 + N −2 2 ). The number T of iterations required in the truncated schemes for the solution of the problem does not depend on the parameter ε, here T = O(ln (min[N 1 , N 2 ])) and T = O(ln ln (min[N 1 , N 2 ])) in the case of the truncated linearized scheme and the truncated Newton scheme, respectively.