Activating and starting method of fischer-tropsch synthetic catalyst

Abstract

An activating and starting method of a fischer-tropsch synthetic catalyst comprises the following steps of (1) adding the catalyst in an activation reactor to activate partial needed fischer-tropsch synthetic wax and preheating to 100-180 DEG C; (2) injecting mixed slurry of the pre-mixed fischer-tropsch synthetic wax and the catalyst in the activation reactor, supplementing the fischer-tropsch synthetic wax to enable the formed mixed slurry to achieve a preset liquid level in the activation reactor, and evenly mixing the fischer-tropsch synthetic wax and the catalyst to be activated; (3) conducting catalyst activation at needed activation conditions; and (4) transporting activated catalyst slurry to a fischer-tropsch synthetic reactor to be used for conducting a fischer-tropsch synthetic reaction. By means of the method, starting cost can be obviously reduced, and buying of a large quantity of paraffin wax and liquid wax is avoided.

Description

technical field [0001] The invention relates to a Fischer-Tropsch synthesis process, more specifically, a method for activating and starting a Fischer-Tropsch synthesis catalyst. Background technique [0002] In the Fischer-Tropsch synthesis reaction process using the slurry bed as the synthesis reactor, since the Fischer-Tropsch synthesis catalyst produced is in an oxidized state, the active phase of the Fischer-Tropsch synthesis reaction is Fe x C. The catalyst needs to be activated before the reaction, so that the catalyst can obtain a stable active phase for the Fischer-Tropsch synthesis reaction. Before the operation of the device, a certain amount of liquid phase medium (slurry bed is three phases) needs to be pre-added in the activation reactor and the synthesis reactor, so that the catalyst is activated in the activation reactor and then transferred to the synthesis reactor. react. [0003] This field usually adopts paraffin wax or liquid wax as the liquid phase me...

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Problems solved by technology

[0003] This field usually adopts paraffin wax or liquid wax as the liquid phase medium used in the Fischer-Tropsch synthesis catalyst activation and start-up process, but finds that adopting paraffin wax or liquid wax as the liquid phase medium of catalyst activation has the following problems in many aspects through device operation experiments: The initial boiling point of paraffin or liquid wax is low. During the catalyst activation process, part of the liquid wax or paraffin is evaporated out of the activation reactor, resulting in a drop in the slurry level during the catalyst activation process. Paraffin or liquid wax needs to be supplemented to maintain the reactor liquid level; Since the temperature of external paraffin or liquid wax is lower than the activation temperature of the catalyst, it has a great influence on keeping the temperature of the reactor constant and affects the effect of catalyst activation; Fischer-Tropsch synthesis catalysts are very sensitive to sulfur, and the sulfur content of paraffin or liquid wax is required to be low If it is less than 0.5ppm, it is necessary to purchase specially processed paraffin or liquid wax. A large amount of liquid wax or paraffin is used during the start-up of the device, resulting in high start-up costs; due to the large difference in physical properties between paraffin wax or liquid wax and the Fischer-Tropsch synthetic wax generated by the reaction, Before replacing most of the paraffin or liquid wax out of the reactor, the properties of the wax product extracted from the reactor have been unstable, and the device is also in an unstable state, resulting in more difficulties in the operation of the device during the start-up process

[0004] In addition, when the activated Fischer-Tropsch synthesis catalyst is transported to the Fischer-Tropsch synthesis unit for the Fischer-Tropsch synthesis reaction, a slurry pump is generally used to transport the slurry containing the catalyst, which causes catalyst wear, reduces catalyst life, and increases the iron content of the Fischer-Tropsch synthesis product. Detrimental to the long-term operation of the device

[0005] In summary, the prior art has not yet disclosed a method for activating and starting the Fischer-Tropsch synthesis catalyst that can effectively solve the above problems