The invention concerns a process and apparatus for cracking ammonia in which heated ammonia gas at super-atmospheric pressure is partially cracked in at least two adiabatic reactors in series with interstage heating in which the feed temperature to a first reactor is higher than the feed temperature to a further reactor to produce a partially cracked ammonia gas which is then fed to catalyst-containing reactor tubes in a furnace to produce a cracked gas comprising hydrogen gas, nitrogen gas and residual ammonia gas. The use of the adiabatic reactors enables more efficient heat integration within the process and the higher temperature in the first reactor enables the use of a nickel-based catalyst in that reactor as an alternative solution to the potential problem of the presence of oil in the ammonia.

A method for enabling gas exchange and chemical reactions with one or more liquid streams contained in a reactive process vessel are provided. One or more exchange layers within the process vessel can be composed of both collector media and releaser media. The exchange layers allow elements to facilitate increased performance of vessel operations by promoting gas component mixing and diffusion. Improved rates of gas component exchange mean less coking and more gas components available for reaction.

Methods and apparatus for upgrading renewable oils stream are described. The method involves using a cooling stream surrounding the tip of the renewable feed line to prevent polymerization/coking. The cooling stream, which comprises gases or liquids that can be converted to valuable products such as olefins, flows into the FCC reaction zone where it mixes with the FCC feed stream and the renewable oil. The renewable oil can be atomized with an atomizing gas.

A fluidized-bed reactor for the gas-phase polymerization of olefins includes (a) an inner chamber with lower and upper portions, (b) a gas distribution grid that partially separates these portions, (c) a recycle line to feed a fluidizing gas to the lower portion, and (d) a polymer discharge channel for downward discharge. A divider wall surrounds part of the discharge channel, creating a first area in the inner chamber that blocks fluidizing gas from entering the lower portion of the inner chamber and reaching the first area.