Nov 25 (Reuters) - Natural gas producer EQT said

on Monday Blackstone would buy non-controlling equity

interests in some of its pipelines for $3.5 billion in cash.

The sale could help the natgas producer reduce the debt pile

it accumulated after the $14 billion purchase of pipeline

operator Equitrans Midstream in July.

The Mountain Valley Pipeline, a 300-mile natural gas line

running from West Virginia to Virginia, entered service in June

after a years-long legal battle over its construction.

EQT's stake in the entity that owns the pipeline is one of

the prized assets within the portfolio being sold.

With the deal, Blackstone would own stakes in Mountain

Valley Pipeline, EQT's transmission and storage assets and the

Hammerhead pipeline.

The transaction is expected to close in the current

quarter.