Must one immerse disposable vessels?
Plans to discard after initial use: All disposable vessels that one plans to discard after its initial use do not need to be immersed in a Mikveh prior to that initial use, and so is the widespread custom. This applies even if the vessel is made of metal, such as a disposable aluminum pan. Thus, one may use disposable baking pans without immersing them, and is certainly not required to empty wine bottles and coffee jars from its content, and immerse them.
Plans to re-use after initial use: If one plans to re-use the disposable vessel on a permanent basis after its initial use it is disputed in Poskim as to whether it requires immersion prior to its continued use. Some Poskim rule the vessel requires immersion. Other Poskim rule it does not require immersion. This dispute applies to disposable vessels made of metal or glass; such as disposable baking pans, wine/beer bottles and coffee jars; while disposable vessels made of plastic do not require immersion.
Pouring back leftovers: Even according to the stringent opinion above, one may pour leftover food back into the disposable vessel, if it still did not complete its initial use. Thus, one may pour leftover wine back into the wine bottle, or leftover coffee back into the coffee jar, or leftover food back into the aluminum pan, even though it was not immersed. If however one plans to reuse the vessel then according to the stringent opinion it may not be replaced into it before immersion. Furthermore, some are particular not to add or return any food to the disposable bottle even if one does not plan to reuse it.
Recycled disposables: Although in today’s times majority of glass and metal bottles are recycled, and hence reused, nevertheless they do not require immersion prior to their initial use being that the bottles and cans are all destroyed and remolded as part of the recycling process and hence all bottles today, even those made of recyclable material, is considered new, and its existence is temporary.
 Maharil Diskin Kuntrus Achron 136 [regarding if food already in vessel]; Chelkas Yaakov 2/47; Minchas Yitzchak 5/32; Rav SZ”A in SSH”K 9 footnote 41
The reason: As by wine and coffee the food is already in the vessel, and the laws of immersion do not require one to remove the food. [Maharil Diskin ibid] Furthermore, only permanent vessels require immersion as according to some Poskim [Shev Yaakov 31, brought in Yad Efraim 120] the obligation of immersing vessels is dependent on if the vessel is Mikabel Tuma, and a temporary vessel that one plans to discard is not Mikabel Tuma. [Chelkas Yaakov ibid and Minchas Yitzchak ibid, based on Rambam Keilim 5/7] In addition, even according to those Poskim [Mahariy Asad 216; Gidulei Taharah 17] who rule that immersion of vessels is not dependent on their status of Kabalas Tuma, the Sages only established the Mitzvah of immersion to meal vessels, and a vessel that does not have a continued use is not considered a meal vessel. [Minchas Yitzchak ibid, based on Gidulei Taharah ibid]
 This means that one plans to use it just like any other kitchen vessel that is purchased in the store, and used for a long time and is only thrown out once it erodes or is usage is maxed out. If however one plans to only use one or two more times and then throw it out, seemingly it would still fall under the allowance brought in Minchas Yiztchak ibid. However see Rav SZ”A in SSH”K 9 footnote 41
 Clear implication of Minchas Yitzchak ibid; Rav SZ”A in SSH”K 9 footnote 41; Madrich Kashrus Eida Hachareidis
 Igros Moshe 2/40; Rav Yaakov Yosef Za”l
 The reason: As a disposable vessel is nullified to the food that is in it, and is thus not sold individually and does not raise the price of the food. Therefore, it is not considered a vessel at all until it is emptied of its content and then re-used. This can be learned from Michaber 314/8 who allows breaking a basket of dates on Shabbos, being it is not considered a vessel and rather like the shell of a nut. Accordingly, it is not obligated to be immersed, as when it was purchased from the gentile it did not have the status of a vessel, and when it did become a vessel after being emptied and reused it already began to the Jew and is as if it was created by a Jew, which exempts it from immersion. [Igros Moshe ibid]
 Madrich Kashrus Eida Hachareidis
 Conclusion of Rav SZ”A in SSH”K 9 footnote 41; So is explicitly evident from Minchas Yitzchak ibid and the Poskim he basis his ruling on that using it for more than one use does not necessarily require it to be immersed if one plans to throw it out, as it is nevertheless not a permanent vessel and is not a meal vessel.
 The Eida Hachareidis is accustomed to use new bottles for their wines and other materials. According to a representative of the Vaad Hakashrus who I spoke with, this is not done because they suspect for a need of immersion of recycled material, but simply because it is cleaner and nicer, as well as that there is no chance that the material was used for non-Kosher food. [Although even in such a case, there is no worry involved as the material is Kashered in the recycling process.]