Method for delaying deposition of sieve plate of extraction column

Abstract

This invention discloses a method for delaying deposition of sieve plate of extraction column, including following steps: applying a condensing liquid generated by the heat exchange of low pressure steam of a phosphoric acid concentration production system, the temperature of the condensing liquid being in the range of 100 to 120 degrees centigrade; applying an extracting agent that will be addedinto the extraction column to a heat exchanger so as to make it execute the heat exchange with the condensing liquid in the heat exchanger and to improve the extracting agent temperature; sending theextracting agent having higher temperature into the extraction column to realize the extraction to the iodine in the phosphoric acid; controlling the temperature of the extracting agent via adjustingthe condensing liquid quantity in the heat exchanger, controlling the temperature difference of the acid temperature before entering and after existing from the column in the range of 5 to 20 degreescentigrade. This invention can reduce the deposition of the sieve plate of the extraction column, improve the system driving rate, thereby improving the running efficiency of the system and realizingthe production cost.

Description

Technical field [0001] The invention relates to the field of chemical engineering, and in particular to a method for delaying fouling of an extraction tower sieve plate. Background technique [0002] Iodine is the basic raw material for the manufacture of inorganic or organic iodide, and it is also an essential nutrient element for human body and plants. It is widely used in medicine, agriculture, dyes, metallurgy, synthetic rubber, national defense and cutting-edge technology. Iodine often exists in a variety of mineral resources in the form of associated minerals. Due to its low grade, it cannot be used well. At present, the world's iodine industry mainly depends on extracting iodine from seawater. Iodine is a purple-black, shiny solid, with metal-like properties, easy to sublime, and the products are mostly granular. The extraction of iodine from phosphate rock is mainly carried out by using phosphoric acid produced by phosphate rock as a raw material. In the process of phosp...

AI Technical Summary

Problems solved by technology

In this state of production, the sieve plate of the extraction tower will be blocked after driving for more than ten hours, causing the system to stop. After parking, it will take one to two days or even longer from cleaning, cleaning, overhauling to the next normal driving, thus greatly The operating efficiency of the system is reduced, resulting in low start-up rate, short cycle and frequent cleaning work