The Recoll KIO slave allows performing a Recoll search by entering an appropriate URL in a KDE open dialog, or with an HTML-based interface displayed in Konqueror.
The HTML-based interface is similar to the Qt-based interface, but slightly less powerful for now. Its advantage is that you can perform your search while staying fully within the KDE framework: drag and drop from the result list works normally and you have your normal choice of applications for opening files.
The alternative interface uses a directory view of search results. Due to limitations in the current KIO slave interface, it is currently not obviously useful (to me).
The interface is described in more detail inside a help file which you can access by entering recoll:/ inside the konqueror URL line (this works only if the recoll KIO slave has been previously installed).
The instructions for building this module are located in the source tree. See: kde/kio/recoll/00README.txt. Some Linux distributions do package the kio-recoll module, so check before diving into the build process, maybe it's already out there ready for one-click installation.
As a sample application, the Recoll KIO slave could allow preparing a set of HTML documents (for example a manual) so that they become their own search interface inside konqueror.