You can send your mining payouts directly to a Kraken deposit address, however there are some things that you should be aware of:
1) Deposit minimums
Payouts from mining pools are not always predictable and may fall below our deposit minimums.
If you receive funds in an amount lower than the minimum deposit value, the funds may not be able to be credited to your Kraken account.
2) Deposit addresses can expire
Typically, addresses will only expire once you generate more than 5 deposit addresses. The oldest address will expire until you are left with a maximum of 5 addresses.
However, there may be some circumstance, such as a change or update to our deposit processing systems, in which your addresses will expire prematurely.
It is best practice to always check if your deposit address is still listed on your deposit page before sending funds.