How to load excel file from hosting storage

I'm using https://github.com/Maatwebsite/Laravel-Excel to analyse Excel file.

I stored excel file in storage folder and store its info in database, the model is called FileUpload, it looks like this:

namespace App;

use Illuminate\Database\Eloquent\Model;

class FileUpload extends Model
{
    protected $fillable = ['file_name',  'file_url',  'file_type'];
}

When I retrieve file data it looks like this

$file->file_url     ==>         "/storage/2/2017_09_25/10__Book2.xlsx"

when I use $file->file_url in view (like download link) it downloads properly, but when I use it in Maatwebsite Excel Facade, I use it like the following

$data = Excel::load( $file->file_url , function($reader) {})->get();

it throws exception like this

(1/1) PHPExcel_Reader_Exception
Could not open E:\Laravel Projects\portal\/storage/2/2017_09_25/44__Book2.xlsx for reading! File does not exist.

Which means it appends (E:\Laravel Projects\portal\) before my storage path, what should I do to read Excel file from internal storage??

If you have any other ideas I'll be much appreciated.