What does the character “ and” mean here?
Thread Content
Why is it called the Second Middle School and Re-refining Oil Pump? What does the character “ and” here mean? I can’t figure it out; experts, please give some advice~
This is the pump used for catalytic cracking distillation; indeed, as mentioned above, it has dual purposes. The process of returning to the tower is called the second intermediate stage, while the process of going to the reaction section is called re-refining. ;P