From the above screenshot it seems that your CATALINA_HOME's PATH is configured to another tomcat directory. So Start Kaldin.sh is processing tomcat from another location instead of inbuilt tomcat.
You need to correct your CATALINA HOME by using below command.
$export CATALINA HOME=KALDIN-2.2DIR/kaldin
*replace KALDIN-2.2DIR with path where you unzipped kaldin folder.
Then start kaldin again.
In the other hand If you want to run tomcat with your existing tomcat. Please follow below instructions.
Copy kaldin directory from KALDIN-2.2_DIR/kaldin/webapps/ into your existing tomcat webapps.
Copy mysql-connector-java-x.x.x.jar & mail .jar from KALDIN-2.2_DIR/kaldin/lib/ into your existing tomcat's lib directory.
Then restart your tomcat.