DSSudokuSolver - A JavaScript Sudoku solving algorithm

I wrote DSSudokuSolver - a sudoku solving algorithm a while back. Is there any possibility that this algorithm can be improved?

Original Algorithm:

CleanElements = function(comp_ary, Qsudoku){
    for(i=0; i<9; i++){
        for(j=0; j<9; j++){
            /*if(Qsudoku[i][j] != ""){
              comp_ary[i][j]=[];
              }*/
            for(k=0; k<9; k++){
                i_index = comp_ary[i][k].indexOf(Qsudoku[i][j]);
                if(i_index != -1){
                    comp_ary[i][k].splice(i_index, 1);
                }
                j_index = comp_ary[k][j].indexOf(Qsudoku[i][j]);
                if(j_index != -1){
                    comp_ary[k][j].splice(j_index, 1);
                }
            }
            if(i < 3){
                i_min = 0;
                i_max = 2;
            }
            else if(i < 6){
                i_min = 3;
                i_max = 5;
            }
            else{
                i_min = 6;
                i_max = 8;
            }

            if(j < 3){
                j_min = 0;
                j_max = 2;
            }
            else if(j < 6){
                j_min = 3;
                j_max = 5;
            }
            else{
                j_min = 6;
                j_max = 8;
            }

            for(i_box=i_min; i_box<=i_max; i_box++){
                for(j_box=j_min; j_box<=j_max; j_box++){
                    index = comp_ary[i_box][j_box].indexOf(Qsudoku[i][j]);
                    if(index != -1){
                        comp_ary[i_box][j_box].splice(index, 1);
                    }
                }
            }
        }
    }
    return comp_ary;
}

FindElements = function(comp_ary, Qsudoku){
    for(i=0; i<9; i++){
        for(j=0; j<9; j++){
            if(comp_ary[i][j].length == 1){
                if (Qsudoku[i][j] == ""){
                    Qsudoku[i][j] = comp_ary[i][j][0];
                    comp_ary[i][j] = [];
                }
            }
        }
    }
    return Qsudoku;
}

IsThereNullElement = function(Qsudoku){
    for(i=0; i<9; i++){
        for(j=0; j<9; j++){
            if(Qsudoku[i][j] == ""){
                return false;
            }
        }
    }
    return true;
}

InitEmptyArray = function(){
    empty_ary = Array();
    for(i=0; i<9; i++){
        empty_ary[i] = Array();
        for(j=0; j<9; j++){
            empty_ary[i][j] = Array();
            for(k=0; k<9; k++){
                empty_ary[i][j][k] = (k+1).toString();
            }
        }
    }
    return empty_ary;
}

DSSolve = function(Qsudoku){
    comp_ary = InitEmptyArray(); //Complementary Array
    window.comp_ary_old = comp_ary;
    IterationMax = 5000;

    while(true){
        IterationMax -= 1;
        comp_ary = CleanElements(comp_ary, Qsudoku);
        console.log(comp_ary);

        if(window.comp_ary_old == comp_ary){
            //implement this.
        }
        else{
            window.comp_ary_old = comp_ary;
        }

        Qsudoku = FindElements(comp_ary, Qsudoku);
        //console.log(Qsudoku);

        if(IsThereNullElement(Qsudoku)){
            return Qsudoku;
        }

        if(IterationMax == 0){
            return null;
        }
    }
}