This code snippet doesn’t disable Divi’s own custom post type called Projects, but rather just removes it from view in the admin area. For numerous reasons you don’t want to remove the Projects custom post type (screwed up templates, time outs, etc.)

<?php //* Mind this opening php tag

add_filter( 'et_project_posttype_args', 'mytheme_et_project_posttype_args', 10, 1 );
function mytheme_et_project_posttype_args( $args ) {
	return array_merge( $args, array(
		'public'              =&gt; false,
		'exclude_from_search' =&gt; false,
		'publicly_queryable'  =&gt; false,
		'show_in_nav_menus'   =&gt; false,
		'show_ui'             =&gt; false

Credit and thanks goes to georgiee on Github. Snippet found in this thread.