VERY large steam system

JimGPE_3

This is a very large building, 35 storys.

There is 175 psi steam and 15 psi steam.

The picture shows the building condensate receiver. I am at a loss as to why it is piped as it is, and I need to tie into this tank with new condensate.

I am bringing intermediate pressure (75 psi) condensate from a drip from the middle of a two-stage pressure reducing station, and I am bringing low pressure condensate from end of main drips and from a condensate return pump. These two condensate streams will be piped separately from the trap to the tank.

Two questions: Why the inverted trap loop, and do I need such a construction to tie my medium and low pressure condensate into this tank?

Thanks.