Method for producing polyaluminum chloride without heating

Abstract

The invention discloses a method for producing polyaluminum chloride without heating. The method comprises the following concrete steps: (1) sequentially adding a waste aluminum chloride liquor generated in a Friedel-Craft reaction, an aluminiferous hydrochloric acid, an industrial hydrochloric acid and water into a heat insulating reaction kettle to prepare a mixed acid in which the percentage of Al2O3 is 1% to 4% and the percentage of HCl is 12% to 18%; (2) adding aluminum oxidized sludge into the mixed acid, stirring for 60-90 minutes until the aluminum oxidized sludge is completely dissolved, heating to the reaction temperature of 60 DEG C to 80 DEG C, controlling the percentage of the HCl in a semi-finished product to be 0.5% to 3.5% and the percentage of the Al2O3 in the semi-finished product to be not less than 5.0%; (3) adding calcium aluminate powder into a semi-finished product liquid, regulating the percentage of the Al2O3 in the reaction liquid to be 11% to 12% and the basicity of the reaction liquid to be 60% to 90%, maintaining the temperature required by the reaction by utilizing the heat generated in the reaction, timing when the temperature rises to 90 DEG C, reaction under preserved temperature for 60-90 minutes and performing a filter pressing treatment to obtain a finished polyaluminium chloride product. By adopting the method to prepare the polyaluminium chloride, the production process is simple, no steam does need to be heated, the emission of acid mist and waste slag is reduced, the production cost is lowered and the recycle of waste resources is realized; therefore, the method is an economical and practical production method which saves energy and reduces emissions.

Description

technical field [0001] The invention relates to a method for producing polyaluminum chloride without heating, in particular to a method for preparing polyaluminum chloride by using the reaction heat of aluminum oxidation sludge and calcium aluminate powder as a heat source. Background technique: [0002] As a typical flocculant product, polyaluminum chloride can be widely used in the physical and chemical treatment of industrial sewage, industrial water and domestic sewage. After years of development, although its production process has become mature, there are still some defects. Among them, one of the more prominent problems is that the production process of most processes still needs supplementary steam heating. This method not only increases the construction and maintenance costs of auxiliary equipment such as boilers, but also consumes a large amount of increasingly scarce resource energy, such as coal, natural gas, etc. Gas, etc., increase the emission of pollutants s...

AI Technical Summary

Problems solved by technology

This method can produce polyaluminum chloride without heating, but there are still some shortcomings: (1) bauxite and calcium aluminate powder are resource-based raw materials, and their prices have been rising all the way, so they are only used as polyaluminum chloride The production cost of raw materials for the aluminum source in chemical aluminum is also increasing year by year; (2) Both bauxite and calcium aluminate powder contain a lot of water-insoluble matter, which leads to a decrease in the yield of the product and a large amount of production waste; (3) ) The acidity of hydrochloric acid used for acid dissolution is relatively high, and the acid mist volatilizes more seriously during the reaction process

In addition, no other heat-free polyaluminum chloride production technology has been retrieved