php sessions generate many files for the application

[eluser]joe_h[/eluser]
A greeting my friends, I have the following problem, I have defined a controller that is responsible for the sessions but when I create the application that the user accessed from the login form, I create multiple files (as creating multiple sessions), which may be this

My controllers is:

Code:

class Login extends CI_Controller {
    var $SID;

    function __construct()
    {
        parent::__construct();
        $this->load->library('session');
        $this->SID = SID;
    }

    public function index(){
        $this->load->view('inicio');
    }

    public function createSession($user){
        if($this->SID != ''){
            $this->loadViews($user);
        }else
            redirect( '/' );    // redirect back to login page
    }

    public function loadViews($user){
        $this->load->view('evento');
        $this->load->view('municipios');
        $this->load->view('paloma');
        $this->load->view('palomero');
        $this->load->view('org_masas');
        $this->load->view('productos');
        $this->load->view('provincia');
        $this->load->view('suelta');
        $this->load->view('ventas');
        $this->load->view('palomas_eventos');

        $data["usuario"] = $user;
        $data["SID"] = $this->SID;
        $this->load->view('index_aplication',$data);
    }

    public function logout()
    {
        $this->session->destroy();
        redirect('/', 'refresh');
    }
}

as well as destroys the session, which redirected to the initial view and I click the back button of the browser, re-creates the session and goes directly?

As might fix this?