Novel electric furnace for producing high-purity sodium sulfide and process method

Abstract

The invention discloses a novel electric furnace for producing high-purity sodium sulfide and a process method. The novel electric furnace comprises a furnace body steel structure, the inner side of the furnace body steel structure is built by a refractory material, and the interior of the electric furnace is divided into two areas by a partition wall, namely a primary reduction smelting area anda secondary clarification separation area; a hole is reserved in the middle of the partition wall, so that liquid sodium sulfide produced in the reduction smelting area enters secondary clarificationseparation area to be subjected to secondary clarification separation; a plurality of graphite electrodes are arranged in the electric furnace to supply heat to the electric furnace; flue is arrangedat the top of the electric furnace. The electric furnace is divided into the primary reduction smelting area and the secondary clarification separation area, the area function is clear, different process control parameters are adopted, the stable product quality is ensured, the graphite electrode serves as a heat supply device and is mainly made of the carbon element, the reduction effect is achieved, and the product quality is not affected.

Description

technical field [0001] The invention belongs to the field of sodium sulfide smelting technology, and in particular relates to a novel electric furnace and a process method for producing high-purity sodium sulfide. Background technique [0002] At present, reverberatory furnace method and rotary kiln method are mainly used in industrial application to produce sodium sulfide from sodium sulfate reduction. The main process flow is: [0003] Reverberatory furnace process 1: [0004] The reverberatory furnace process flow is: sodium sulfate crystal → batching with reducing agent → smelting in reverberatory furnace → water dissolution at the weir mouth → crystallization to produce sodium sulfide. [0005] The sodium sulfate crystals are mixed with a reducing agent, and then put into the reverberatory furnace through a feeder car for reduction smelting. The smelted sodium sulfide melt is discharged into the water-soluble system through the weir, and the sodium sulfide aqueous sol...

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Problems solved by technology

[0011] (1) The reverberatory furnace process treats sodium sulfate intermittently and in batches, and because the sodium sulfate reduction process is a strong endothermic process, after the mixture of sodium sulfate and reducing agent is added to the reverberatory furnace through the feeder, a cold zone appears at the stockpile , the chemical speed is slow;

[0012] (2) The reverberatory furnace belongs to radiation heating, which cannot effectively heat the reaction stockpile, and the heat utilization is low, which further aggravates the slow speed of the chemical material, and then forms freezing and stockpile in the feeding area;

[0013] (3) The reverberatory furnace is heated by natural gas combustion, and the furnace is always in a micro-oxidizing atmosphere, which is likely to cause secondary oxidation of sodium sulfide products, resulting in irreversible product quality effects

[0015] (1) The reduction temperature of the rotary kiln is below 650°C, and it is necessary to add catalysts containing iron and nickel to promote the reduction reaction of sodium sulfate, which will deteriorate the product quality;

[0016] (2) The reduction temperature of the rotary kiln is between 750°C and 800°C. At this time, the conversion rate increases and no catalyst is needed. However, with the increase of sodium sulfide content in the reaction process, the lowest eutectic point of the sodium sulfide-sodium sulfate mixture cannot be circumvented. At 665°C, there are problems such as material melting and sticking to the wall, incomplete reaction and difficulty in discharging;

[0017] (3) The contact between gas-solid reaction materials is uneven, the product stability is poor, and the quality cannot be guaranteed

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