A reservoir for one or more chemical reactants has means for heating the reactants and optional means for stirring the reactants. A pumped reactant feed line and a return line provide fluid communication between the reservoir and a 4-way valve system. The 4-way valve system is also in fluid communication with a reactor vessel and a source of inert gas for purging the system. In a first state, the 4-way valve provides fluid communication between the reservoir and the reactor. In a second state, the 4-way valve provides a continuous circulation path for the heated reactants from the reservoir, to the valve system, and back to the reservoir via the return line. In a third state, the 4-way valve provides a fluid pathway for purging the reactor with inert gas. In a fourth state, the 4-way valve provides a fluid pathway for purging the reservoir with inert gas.

The present invention relates to a method for producing liquid or solid hydrocarbons from a synthesis gas via Fischer-Tropsch synthesis which does not carry out a separate reduction pre-treatment for catalyst activation. The method for producing liquid or solid hydrocarbons from a synthesis gas using Fischer-Tropsch synthesis according to the present invention comprises: a first step of applying an iron-based catalyst for the Fischer-Tropsch synthesis in which the number of iron atoms in the ferrihydrite phase fraction equals 10 to 100% and the number of iron atoms in the hematite phase fraction equals 0 to 90%, with respect to 100% of the number of the number of iron atoms, to a Fischer-Tropsch synthesis reactor; and a second step of activating the catalyst for the Fischer-Tropsch synthesis by a synthesis gas which is a reactant under the conditions of the Fischer-Tropsch synthesis and carrying out the Fischer-Tropsch synthesis by means of the activated catalyst for the Fischer-Tropsch synthesis. As such, the present invention is capable of efficiently producing liquid or solid hydrocarbons from a synthesis gas via Fischer-Tropsch synthesis, even without a separate reduction pre-treatment.

The invention relates to a process for the preparation of a polyolefin in a reaction system from one or more -olefin monomers of which at least one is ethylene or propylene, 5 wherein the reaction system comprises a reactor, a product purge bin, a granular feed bin, wherein the granular feed bin is located downstream of the product purge bin, a recovery unit and an extrusion unit directly coupled to the granular fed bin, wherein the reactor comprises a fluidized bed, an expanded section located at or near the top of the reactor, a distribution plate located at the lower part of the reactor and an 10 inlet for a recycle stream located under the distribution plate, wherein the process comprises a) feeding a polymerization catalyst to the fluidized bed in the area above the distribution plate, b) feeding the one or more -olefin monomers to the reactor, 15 c) circulating fluids from the top of the reactor to the bottom of the reactor, wherein the circulating fluids are cooled using a heat exchanger, resulting in a cooled recycle stream comprising liquid, and wherein the cooled recycle stream is introduced into the reactor using the inlet for the recycle stream, d) withdrawing a stream comprising the polyolefin and fluids from the reactor and 20 passing said stream into the product purge bin, e) purging the product purge bin with a purge stream comprising a first inert gas, preferably nitrogen and steam such that a stream comprising a purged polyolefin and a stream comprising fluids, wherein the stream comprising the fluids is substantially free of steam, is obtained, 25 f) introducing at least part of the stream comprising the fluids back into the reactor via the recovery unit, g) introducing the stream comprising the purged polyolefin into the granular feed bin and h) contacting a deactivating stream comprising steam with the purged polyolefin in the 30 granular feed bin to obtain a polyolefin that is substantially free of active polymerization catalyst.

A reservoir for one or more chemical reactants has means for heating the reactants and optional means for stirring the reactants. A pumped reactant feed line and a return line provide fluid communication between the reservoir and a 4-way valve system. The 4-way valve system is also in fluid communication with a reactor vessel and a source of inert gas for purging the system. In a first state, the 4-way valve provides fluid communication between the reservoir and the reactor. In a second state, the 4-way valve provides a continuous circulation path for the heated reactants from the reservoir, to the valve system, and back to the reservoir via the return line. In a third state, the 4-way valve provides a fluid pathway for purging the reactor with inert gas. In a fourth state, the 4-way valve provides a fluid pathway for purging the reservoir with inert gas.

Slurry flow valves may be used to control flow in a gas-phase polymerization reactor. For example, a system may include at least three injection nozzles fluidly connected to a gas-phase polymerization reactor, wherein the at least three injection nozzles are configured to carry' a modified catalyst slurry; at least three lines connected to the at least three injection nozzles, wherein the at least-three lines comprise a first line connected to a first injection nozzle, a second line connected to a second injection nozzle, and a third line connected to a third injection nozzle; and at least three slurry? flow valves in contact with the at least three lines, wherein the at least three slurry flow valves comprise a first slurry flow valve, a second slurry flow valve, and a third slurry' flow valve. Preferably, the valves can each be independently controlled to regulate flow therethrough.