As it is mentioned in the Koranic verses, Hell as well as the Heaven has an eternal aspect, meaning those who deserve severe torments will live in Hell for ever as their punishment:
1- Who do not appeal to any other deity God [Alone], nor kill any soul whom God has forbidden [them to] except through [due process of] law, nor misbehave sexually. Anyone who does so will incur a penalty.
Torment will be doubled for him on Resurrection Day and he will remain disgraced forever in it , except for someone who repents and believes and acts in an honorable manner . God will replace their evil deeds with fine ones, since Gods is forgiving, Merciful.
Anyone who repents and acts hanrbly should turn to God in re repentance. (25:68-71)
2- Anyone who kills a believer deliberately will receive as his reward [a sentence] to live in Hell forever.(4:93)
3- So I have warned you (all) about a raging fire. Only the most wretched will roast in it, the one who rejects [the Message] and turns away.( 92: 14-16)
4- Those who disbelieve and reject our signs will become inhabitants of the Fire, to remain there. What an awful goal it is! (64:10)
5-Yet criminals will remain in Hell torment. (43:74)
The following verses also present the reasons leading to staying in Hell forever:
1- While those who disbelieve and reject our signs will become inmates of the fire , they shall remain in it! (2:39)
2-While those who reject My signs and act too haughty towards them will become inmates of the fire , they will remain there forever.(7:36)
3-Heavens gates will nor swing open for those who reject Our signs and feel too proud for them, nor will they enter the Garden until a camel can be led through the eye of a needled . Thus we reward criminals. (7:40)
4-Those who reject our signs and [the idea of] a meeting in the hereafter will [see] their works collapse. Will they not be rewarded for just what they have doing?( 7: 147)
5- We shall gradually bring those who reject our signs from a place they do not recognize. (7:182)
6- Those who deny [they will have] any meeting with God have already lost-out, so that when the How comes suddenly upon them , they will say: “ Have pity on us haw we neglected it!” “they will carry their burdens on their own backs. Is not whatever they bear something?” (6:31)