PHP Excel使用zend框架生成

When I am going to generate an EXCEL file using PHPExcel class in zend framework I will get an error when data is more than 20 days ERROR IS

File not found

Firefox can't find the file at http://eyeq.local/eyeq/reports/reading-speed-analysis-report/op/export/organization_id/1/department_id//from_date/03-12-2013/to_date/04-01-2013/userType/1/user_id//reportSize/full.

Check the file name for capitalization or other typing errors. Check to see if the file was moved, renamed or deleted.

I have already increased execution time to 18000 and memory limit to 256m

The department_id is empty in the url

i.e. URL*...../department_id/[THIS SHOULD BE AN INT]/from_date......*