Integrate YII2 orm to my project code

I have a project which created before I heard yii2.

If I use yii2 to re-implement this project, there is a huge work to do.

are there some possible that I use yii2 orm only? It means I will use AR, QueryBuilder and DAO on my own project

You can read this guide.

See section "Using Yii in Third-Party Systems".

thank you very much.

I found that after I post this.