TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Installation Details: The entry point (D) is between the stop valve and the separation section. The flushing fluid may be a liquid or gas under pressure. The mechanism for stopping circulation in the external circuit and for flushing out the slurry comprise a sectioning valve, means for connecting the point (D) with a fluid source under pressure and a free volume in the upper part of the reactor which is greater than the volume of the liquid/solid suspension in the circuit and in the separation section. The installation comprises a control center with communication to the valve system in the external circuit. The reactor section comprises a system for injection of the reactive gas at a number of points and means for stirring so proportioned that deposition of solids above the injection points is avoided. The pumping system in the external circuit is such as to maintain the Reynolds number of the slurry between 2500 and 500000 at any point in the circuit. The installation also comprises a condensing system for part of the effluent gases with a storage vessel which is connected to the means for introduction of flushing fluid. The suspended solid is catalyst for the Fischer-Tropsch reaction and the pressurized fluid is chemically compatible with the catalyst.Preferred Process Details: The flushing fluid comprises a part of the effluent of the Fischer-Tropsch reaction. The flushing fluid may be a gas such as N2, H2, CO or hydrocarbons (liquid or vaporized) with less than 20C, or mixtures of these. The flushing fluid has a solidification point less than that of the liquid phase of the slurry and preferably less than ambient temperature. EXAMPLE - The liquid under pressure contained in the lower part of the condensation receiver is obtained by condensation of the gases from the reactor after passing through an exchanger. The gases contain mainly light hydrocarbons, and are condensed at 50 degrees C then pumped, reheated and partially vaporized to produce a gas and liquid at a pressure higher than in the slurry circulation circuit. The fluid sources are chemically compatible with the iron or cobalt catalyst.