Methods for defoaming in hydrocarbon processes include the steps of providing a defoaming agent, and introducing the agent into a hydrocarbon process to inhibit or control foaming in the hydrocarbon process. These methods may be particularly useful in coking processes, especially as to foaming in coke drums. In certain embodiments, defoaming agents may comprise a plurality of carbon nanoparticles. In some embodiments, drag reducing agents may comprise high-molecular weight alkanes. Advantages include, but are not limited to, more efficient and effective foam inhibition, reduced or eliminated product contamination, reduced or eliminated catalyst poisoning, increased refinery production rate, debottlenecking the coker, and reduced cost and consequences of applying too much antifoam.