"Every day I am in the laboratory at least for ten hours."
Translation:Her gün en az on saat laboratuvardayım.
There are two issues.
1) Your word order is off. It could possible be said like this in spoken Turkish, but written Turkish is a bit more stringent in its word order. Verbs (or nouns/adjectives with the personal suffix) should come at the end of the sentence. " laboratuvardayım" needs to be at the end.
2). "saattır" cannot be used here. You can only use the -DIr suffix on time expressions from ongoing action. This is talking about a general habit and is not current ongoing action. It would be used in a situation like "I have been living here for two years" (it is still happening) or "I have been reading for an hour" (it is still happening). :)