You MAY be able to find some local OTC traders that are capable of handling that much liquidity of a daily basis. You can find them through an OTC broker, or even localbitcoins (click on their ad, if they offer OTC f2f trading they'll usually list as so).

But the rates you get may be slightly worse than on exchange. Depends on where you're located, there is a bunch of international exchanges not located in the USA such as Kraken and Bitstamp that may be able to assist you.

Though if you are using an exchange you need to consider the fact that the orderbook may not have sufficient liquidity, and you may end up getting worse rates for the last few sell orders you place.