"He will also drink of the wine of the anger of God that is poured out undiluted into the cup of his wrath, and he shall be tormented with fire and sulphur in the sight of the holy angels and in the sight of the Lamb. And the smoke of their torment ascends forever and ever, and day and night they have no rest, those who worship the wild beast and its image, and whoever receives the mark of its name." - NWT
But is Rev. 14:10, 11 really proof of the existence of a fiery Hell?
First, it is clear that the book of Revelation is a book full of symbols and of figurative (not literal) language. So when the rest of the Bible clearly shows how when someone dies, they are not conscious of anything (Ps. 146:4; Ecclesiastes 9:5) and that the condition of the dead is one of inactivity - likened to a deep sleep (Ps. 13:3; John 11:11-14; Acts 7:60; 1 Cor. 7:39; 15:51; 1 Thess. 4:13), it would seem reasonable to conclude that what was written at Rev. 14:10, 11 is indeed phrased in figurative or symbolic terms. (Also see: A Closer Look at Some Myths About Death w02 p. 5-86/1 p; Watchtower Online Library)
(Also, it is important to note that it is the SMOKE that ascends forever...NOT the "torment".)
Below is a small excerpt from the WBTS publication Revelation - It's Grand Climax at Hand. It provides an excellent examination of the use of the words "fire and brimstone" and how some can be "tormented with fire and sulphur":
Some have viewed the mention here (Rev. 14:10b, 11) of fire and sulfur ("fire and brimstone," King James Version) as a proof of the existence of a hellfire. But a brief look at a similar prophecy shows the real import of these words in this context. Back in the days of Isaiah, Jehovah warned the nation of Edom that they would be punished because of their enmity toward Israel. He said: "Her torrents must be changed into pitch, and her dust into sulphur, and her land must become as burning pitch. By night or by day it will not be extinguished; to time indefinite its smoke will keep ascending. From generation to generation she will be parched; forever and ever no one will be passing across her."—Isaiah 34:9, 10.
Was Edom hurled into some mythical hellfire to burn forever? Of course not. Rather, the nation completely disappeared from the world scene as if she had been totally consumed with fire and sulfur. The final result of the punishment was not everlasting torment but "emptiness . . . wasteness . . . nothing." (Isaiah 34:11, 12) The smoke `ascending to time indefinite' vividly illustrates this. When a house burns down, smoke keeps coming from the ashes for some time after the flames have died down, providing onlookers with evidence that there has been a destructive conflagration. Even today God's people remember the lesson to be learned from the destruction of Edom. In this way `the smoke of her burning' is still ascending in a symbolic way.
Those who have the mark of the wild beast will also be destroyed completely, as if by fire. As the prophecy later reveals, their dead bodies will be left unburied for animals and birds to eat. (Revelation 19:17, 18) So, clearly, they are not being literally tortured forever! How are they "tormented with fire and sulphur"? In that the proclamation of truth exposes them and warns them of God's coming judgment. Therefore they vilify God's people and, where possible, slyly persuade the political wild beast to persecute and even kill Jehovah's Witnesses. As a climax, these opposers will be destroyed as with fire and brimstone. Then "the smoke of their torment ascends forever and ever" in that God's judgment of them will serve as a touchstone if ever again Jehovah's rightful sovereignty is challenged. That issue will have been settled for all eternity. - Revelation - It's Grand Climax at Hand, Chapter 30 "Babylon the Great Has Fallen!", par. 14-17
The Biblical Hell (Jehovah's Witnesses United)
What Really Is Hell? (w02 7/15 pp. 5-7; Watchtower Online Library)
Hell - Links to Information (Search For Bible Truths)