Menachot 22b מנחות כ״ב ב

From here it is learned that with regard to a mixture of items that ascend to the altar, e.g., the blood of the bull and the goat, the different components of the mixture do not nullify one another. And Rabbi Yehuda holds: From here it is learned that any substance in contact with the same type of substance is not nullified.

The Gemara examines Rabbi Yoḥanan’s explanation of the dispute between the Rabbis and Rabbi Yehuda. With regard to the first part of his explanation, that the Rabbis hold: From here it is learned that with regard to a mixture of items that ascend to the altar the different components of the mixture do not nullify one another, the Gemara suggests: But perhaps the blood of the goat is not nullified when mixed with the blood of the bull due to the fact that it is a substance in contact with the same type of substance.

The Gemara answers: Had the verse taught us this halakha by using an example of a substance in contact with the same type of substance, and not taught us a case of a mixture of items that ascend to the altar, the verse would be interpreted as you said. But now that the verse taught us this halakha through a case of a mixture of items that ascend to the altar, it is understood that the reason it is not nullified is due to the fact that it is part of a mixture of items that ascend to the altar, not because the substances are of the same type.

The Gemara suggests: But perhaps it is not nullified until both criteria are met, and unless the mixture is both a substance in contact with the same type of substance and a mixture of items that ascend to the altar, one nullifies the other. The Gemara concedes: This is difficult.

With regard to the second part of Rabbi Yoḥanan’s explanation: And Rabbi Yehuda holds: From here it is learned that any substance in contact with the same type of substance is not nullified, the Gemara suggests: But perhaps the blood of the goat is not nullified when mixed with the blood of the bull due to the fact that it is a mixture of items that ascend to the altar.

The Gemara answers: Had the verse taught us this halakha by using an example of a mixture of items that ascend to the altar where the substance is in contact with a different type of substance, the verse would be interpreted as you say. But now that the verse taught us this halakha in a case of a substance in contact with the same type of substance, it is understood that the reason it is not nullified is due to the fact that it is a substance in contact with the same type of substance.

The Gemara suggests: But perhaps it is not nullified until both criteria are met, and unless the mixture is both a substance in contact with the same type of substance and a mixture of items that ascend to the altar, one nullifies the other. The Gemara concedes: This is difficult.

The Gemara raises another objection to the explanation of Rabbi Yoḥanan: We learned in the mishna here that Rabbi Yehuda says: If the handful was intermingled with the meal offering of priests, with the meal offering of the anointed priest, or with the meal offering of libations, the mixture is unfit because with regard to this, the handful from the standard meal offering, its mixture is thick, and with regard to that, the meal offering of the anointed priest and the meal offering of libations, its mixture is loose. And the mixtures, which are not identical, absorb from each other, invalidating both. The Gemara asks: But when the mixtures absorb from each other, what of it? This is a case of a substance in contact with the same type of substance, and therefore neither oil nullifies the other and both should be sacrificed on the altar.