Using files session handler, getting error for memcache

Just switched to php 7.1 and started getting an error:
   Message: session_start(): Cannot find save handler 'memcache' - session startup failed
   Filename: Session/Session.php 
   Line Number: 143

This happens when running the second line in the following, in _construct() of the controller:
        $this->load->database();
        $this->load->library(array('session','user_agent','form_validation'));

This is what I have in application/config/config.php:
    $config['sess_driver'] = 'database';

    $config['sess_save_path'] = 'ci_sessions';

    $config['sess_cookie_name'] = 'ih_sss';

    $config['sess_expiration'] = 1800;

    $config['sess_match_ip'] = FALSE;

    $config['sess_time_to_update'] = 300;
   $config['sess_regenerate_destroy'] = FALSE; 

Any help to try to sort this out would be much appreciated. 
Thanks.

Er, you say you are using *files* sessions, but your config says *database* sessions, and you are getting a *memcache* error? Something doesn't make sense here

Sorry for the mistake: it is database!
Any suggestions?

Just found that this is what there is in the / directory, in php.ini:

extension=memcached.so
extension=memcache.so 
...
session.save_handler = memcache
session.save_path = "tcp://10.168.1.55:11211?persistent=0&weight=1&timeo

The date on php.ini is 25/7/2017, a year before I changed to php 7.1, and it did not have any effect when running php 5.6.

Could this be it? Php overriding the setting in CI config.sys?

YES, that was it.
When removing php.ini, everything works ok.