Start-up method of zinc sulfide concentrate roasting and flue gas acid-making system

Abstract

The invention discloses a start-up method of zinc sulfide concentrate roasting and flue gas acid-making system. The method includes the steps of: 3-10h before feeding of a zinc sulfide concentrate roasting furnace, detecting the tail gas absorption liquid of flue gas treated by a flue gas acid-making system, and when the concentration of hydrogen peroxide is larger than or equal to 1.50% and the concentration of dilute acid is smaller than or equal to 10.0%, starting feeding; and in the flue gas acid-making system, when the temperature of a first-stage catalyst of a converter reaches 420DEG Cor above, the temperature of a second-stage catalyst of the converter reaches 420DEG C or above, the temperature of a fourth-stage catalyst of the converter reaches 405DEG C or above, and the temperature of a third-stage catalyst of the converter reaches 410DEG C or above, completing the start-up. According to the application, through precise correspondence of the roaster blast volume, the feedingamount, a catalyst temperature and the SO2 concentration, under the condition of not increasing the investment, power consumption and energy consumption, good treatment of tail gas by the flue gas acid-making system in a start-up process after new construction or overhaul can be ensured, and the discharged tail gas completely reaches the standard. The method provided by the invention guarantees up-to-standard emission of tail gas, also achieves efficient recovery of resources, and has good economic benefits.

Description

technical field [0001] The invention belongs to the technical field of acid production from smelting flue gas, and relates to an environmental protection and energy-saving technology in the technical field of acid production from smelting flue gas. In particular, it relates to a method for starting up a zinc sulfide concentrate roasting system and a flue gas acid production system. Background technique [0002] At present, most large-scale zinc smelting enterprises adopt the mature hydrometallurgy zinc smelting process for zinc smelting. In this process, the zinc sulfide concentrate is first roasted, and the zinc oxide calcined sand produced by roasting is subjected to wet smelting such as dilute sulfuric acid leaching and electrowinning. The zinc process produces electric zinc, and the SO produced by roasting 2 The flue gas is cooled by the waste heat boiler, dusted by cyclone and electric dust collection equipment, and then sent to the acid production process for the prod...

AI Technical Summary

Problems solved by technology

In the prior art, during the start-up process of the system after new construction or overhaul, due to the low temperature of the catalyst layer of the converter, the indicators such as the air blast volume of the roaster, the feeding volume, and the concentration of SO2 in the flue gas are different from those of the The temperature of the catalyst layer of the converter does not match, resulting in a low conversion rate of SO2 in the flue gas, and the content of SO2 in the tail gas of the acid production exceeds the standard, which causes great damage to the environment after discharge hazards, and the emission of SO2 also causes waste of resources

[0004]Currently, the heating electric furnace of the flue gas SO2 conversion system is mainly carried out project transformation, increasing the power to increase the temperature of the catalyst layer, thereby Improve the conversion rate of SO2, but this method consumes a lot of energy during the start-up of the system, which greatly increases the cost of system start-up, and reduces the SO2 in the exhaust gas At the same time, it causes a great consumption of energy and poor economic benefits

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