NOVELTY - An alkylation process comprises at least partially condensing at least a portion of a compressed stream to form a condensed stream comprising an alkylation substrate; indirectly exchanging heat in the refrigerant heat exchanger (22) from at least a portion of the condensed stream to at least a portion of the refrigerant exchanger feed; and recycling at least a portion of the chilled recycle stream to the reactor (10).    USE - For alkylation process.    ADVANTAGE - The process helps to recycle light components, such as hydrogen chloride, and to cut hydrogen chloride losses, without excessive compression costs.    DETAILED DESCRIPTION - An alkylation process comprises alkylating an alkylation substrate with an alkylating agent to form alkylate in a reactor; recovering from the reactor a reactor effluent comprising the alkylate and the alkylation substrate; flashing at least a portion of the reactor effluent to form a refrigerant exchanger feed comprising the alkylate and the alkylation substrate, where refrigerant exchanger feed has the same composition as the at least a portion of the reactor effluent; heating at least a portion of the refrigerant exchanger feed in a refrigerant heat exchanger, and recovering from the refrigerant heat exchanger a refrigerant exchanger effluent comprising the alkylate and the alkylation substrate; passing at least a portion of the refrigerant exchanger effluent to an effluent vapor-liquid separator (26), and recovering from the effluent vapor-liquid separator a vapor phase comprising the alkylation substrate and a liquid phase comprising the alkylate; compressing the vapor phase to form a compressed stream comprising the alkylation substrate; at least partially condensing at least a portion of the compressed stream to form a condensed stream comprising the alkylation substrate; indirectly exchanging heat in the refrigerant heat exchanger from at least a portion of the condensed stream to the at least a portion of the refrigerant exchanger feed, to form a chilled recycle stream comprising the alkylation substrate; recycling at least a portion of the chilled recycle stream to the reactor; and recovering the alkylate from the liquid phase.    DESCRIPTION OF DRAWING(S) - The figure shows alkylation process.    Reactor (10)    Refrigerant heat exchanger (22)    Effluent vapor-liquid separator (26)    Water-cooled condenser (36)    Product recovery section (88)