Can a soul be delivered from hell through our prayers?
The short answer
No. Like heaven, hell is eternal, so prayers cannot help the souls there. Souls in heaven need no prayers either; only those in purgatory are helped by our prayers for the dead.
Hell is eternal
The Catechism affirms the existence and eternity of hell: those who die in mortal sin go immediately to hell, whose chief punishment is eternal separation from God, in whom alone we find the life and happiness we were made for (CCC 1035). Prayers cannot help souls there.
Who our prayers help
Souls in heaven have no need of our prayers. Only those in purgatory are helped by prayers for the dead.