Technique for preparing activated carbon from wood raw material by external-heating-free one-step process and carbon activating device

Abstract

The invention provides a technique for preparing activated carbon from a wood raw material by an external-heating-free one-step process and a carbon activating device. An internal-heating drying converter, an external-heating carbonization converter and an internal-heating activating converter are utilized to prepare the activated carbon; the wood raw material is dried in the internal-heating converter to remove moisture by using heating exhaust of the external-heating carbonization converter; the generated water vapor is discharged via a chimney came along the drying medium, thereby avoiding influencing the flammability since the water vapor is mixed with the combustible gas generated during carbonization; the dried raw material falls into the external-heating carbonization converter to perform carbonization, wherein the heating medium is high-temperature activated exhaust from the activating converter; the combustible gas generated in the carbonization process is introduced into the activating converter; the inner wall of the activating converter is also provided with a vapor pipe; a right amount of superheated water vapor can be introduced to perform activating reaction with carbon at high temperature so as to generate hydrogen, carbon monoxide and other combustible gases; the inner wall of the activating is provided with an air pipe; and a proper amount of air can be introduced to combust the combustible gas, thereby keeping the activating temperature.

Description

1. Technical field [0001] The present invention relates to the technology of making activated carbon by using woody raw materials, in particular to a one-step method of making activated carbon by using woody raw materials without external heating and carbon activation equipment. 2. Background technology [0002] At present, there are two main methods of making activated carbon from woody raw materials: one is powdery raw materials such as bamboo chips or wood chips, mainly using zinc chloride or phosphoric acid as an activator to prepare powdery activated carbon by internal heating in a rotary furnace, which has waste gas and The problem of waste water polluting the environment will be limited in many areas with strict environmental protection; the other is the two-step water vapor activation method of fruit shells or wood (bamboo) chips or powdery activated carbon, which needs to first remove the fruit shells or wood (bamboo) ) shavings are carbonized to make fruit shell ch...

AI Technical Summary

Problems solved by technology

[0002] At present, there are two main methods of making activated carbon from woody raw materials: one is powdery raw materials such as bamboo chips or wood chips, mainly using zinc chloride or phosphoric acid as an activator to prepare powdery activated carbon by internal heating in a rotary furnace, which has waste gas and The problem of waste water polluting the environment will be limited in many areas with strict environmental protection; the other is the two-step water vapor activation method of fruit shells or wood (bamboo) chips or powdery activated carbon, which needs to first remove the fruit shells or wood (bamboo) ) shavings are carbonized to make fruit shell charcoal or wood (bamboo) shavings charcoal, and then use husk charcoal or wood (bamboo) shavings charcoal as raw materials to make granular or powdered activated carbon by steam activation. The activation process requires additional fuel heating to achieve And maintain the temperature required for activation, the energy consumption is relatively large

At present, whether it is physical activation method or chemical activation method to produce activated carbon, it needs to consume fuels such as coal, gas or firewood. The high-temperature activation tail gas must be discharged into the air through the chimney, which will waste heat energy and cause high fuel costs. At the same time The flue gas produced by the combustion of additional coal will pollute the atmospheric environment

[0003] Similar patents related to the one-step process of activated carbon from wood materials include: the invention patent of patent No. ZL201010181027.7, which refers to the production of powdered activated carbon by one-step water vapor activation after wood chips are formed, and requires that the wood chips be pressed into granules and then used in a vertical The process of making activated carbon by moving bed activation furnace is cumbersome, and the molding of wood chips requires energy consumption; the invention patent application number is 201110337017.2. The method of one-step production of activated carbon by using rotary activation furnace for wood chips and by-product gas, which uses wood chips raw materials from the rotary furnace One end of the rotary kiln is added, after drying, carbonization and activation in the rotary kiln, the material is discharged from the other end of the rotary kiln. There are two defects: one is that the airflow of the converter flows to the discharge end, and the temperature of the feed end of the converter is relatively high. Low, wood chips are not easy to be dried and carbonized, so combustible gas cannot be produced, so it is difficult to raise the temperature of the feed end of the converter, the front part of the converter does not play a good role, and the wood chips are transported to the higher temperature part with the rotation of the converter When it meets with air, it is easy to catch fire and reduce the yield of activated carbon. The drying, carbonization and activation of wood chips are all carried out in the latter part of the converter. The activation zone is shorter, and the activation time in the converter is shorter, thus affecting the activation effect and products. Second, the water vapor generated during the drying process of sawdust is mixed with the combustible gas generated during carbonization, which will reduce the flammability of the combustible gas

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