CN104028538B - Red mud after acidifying - Google Patents

Abstract

The invention discloses the red mud after a kind of acidifying, the main points of its technical scheme are, the red mud batching after acidifying is made up of red mud, Concave-convex clay rod, magnesia, sulfuric acid, quick dissolved sodium silicate, polyvinyl alcohol, hydroxypropyl methylcellulose and sodium carbonate.The production method of the red mud after acidifying: by abrasive dust in the red mud batching input grinding machine after acidifying, the powder after abrasive dust is the red mud after acidifying.The production method of the red mud after acidifying takes first acidifying to carry out compounding ingredient again, can avoid sulfuric acid and quick dissolved sodium silicate, polyvinyl alcohol, hydroxypropyl methylcellulose and sodium carbonate generation chemical reaction; After the acidified process of red mud, the utilization rate of red mud can be improved, not only can bring good economic benefit, environmental benefit and social benefit, and can realize turning waste into wealth.Red mud after acidifying has the high feature of good thixotropy, heat endurance, plasticity, caking property and dry compression.Red mud after acidifying is applicable to produce construction material, blowing agent and fire product.

Description

Red mud after acidifying

Technical field

The present invention relates to acidification, be specifically related to the red mud after a kind of acidifying.

Background technology

The contaminative waste residue of discharging when red mud is aluminium industry extraction aluminium oxide, average often produces 1 ton of aluminium oxide, incidentally produces 1.0 ~ 2.0 tons of red muds.The pH value of red mud is 10 ~ 12, and China is as large alumina producing state of the world the 4th, and the red mud of annual discharge is up to millions of tons.A large amount of red muds can not fully effectively utilize, large-area stockyard can only be relied on to stack, occupy a large amount of soil, the generation of red mud causes directly many-sided on the production of the mankind, life and indirectly affects, so reduce output and the harm of red mud to greatest extent, realize by all kinds of means, the resource of quantity is extremely urgent greatly.

Summary of the invention

The object of the invention is to overcome weak point in prior art, the red mud after a kind of acidifying is provided.

Red mud batching after acidifying is made up of red mud, Concave-convex clay rod, magnesia, sulfuric acid, quick dissolved sodium silicate, polyvinyl alcohol, hydroxypropyl methylcellulose and sodium carbonate.

The production method of the red mud after acidifying: by abrasive dust in the red mud batching input grinding machine after acidifying, the powder after abrasive dust is the red mud after acidifying.

China is alumina producing big country, within 2009, produces 2,378 ten thousand tons, aluminium oxide, accounts for 30% of Gross World Product, nearly 3,000 ten thousand tons of the red mud of generation.Current China red mud comprehensive utilization ratio is only 4%, and accumulation volume of cargo in storage reaches 200,000,000 tons.Along with the reduction gradually of growth and the bauxite grade year by year of China's aluminium oxide output, the year generation of red mud also will constantly increase, and expect 2015, and red mud adds up volume of cargo in storage will reach 3.5 hundred million tons.

Concave-convex clay rod has unique layer chain structure feature, and crystal is needle-like, threadiness or fiber collection shape.Concave-convex clay rod has unique dispersion, high temperature resistant, anti-good colloidal nature and the higher adsorption capacity such as saline and alkaline, and has certain plasticity and cohesive force.

Magnesia has the general character of basic anhydride, belongs to Binder Materials, can improve the colloidal property of red mud.

Sulfuric acid select concentration be 98% the concentrated sulfuric acid.

Quick dissolved sodium silicate is white powder material, can rapid solution in water, have that cohesive force is strong, intensity is higher, acid resistance, good heat resistance, the feature of alkali resistance and poor water resistance.

Polyethenol series white solid, external form divide cotton-shaped, graininess, Powdered three kinds; Nonpoisonous and tasteless, graininess can be dissolved in 80--90 DEG C of water, pulverous other powders pre-dispersed after can dissolve at normal temperatures.There is good viscosity, polymerism, caking property and water-retaining property.

Hydroxypropyl methylcellulose has thickening capabilities, salt discharge, pH stability, water-retaining property, dimensional stability, excellent film forming and the feature such as resistance to enzymatic, dispersiveness and caking property widely.

Sodium carbonate has the general character and the heat endurance of salt, soluble in water, and its aqueous solution is alkalescence, in the present invention for adjusting the red mud pH value after acidifying.

The present invention is achieved by following technical proposals:

1, the red mud batching after acidifying is made up of following component by weight percentage: the red mud semi-finished product 90 ~ 98% after acidifying, quick dissolved sodium silicate 0.1 ~ 5%, polyvinyl alcohol 0.1 ~ 5%, hydroxypropyl methylcellulose 0.01 ~ 3% and sodium carbonate 0 ~ 3%.

The production method of the red mud 2, after acidifying: by abrasive dust in the red mud batching input grinding machine after acidifying, grain fineness≤0.074 millimeter, the powder after abrasive dust is the red mud finished product after acidifying.

3, the half-finished production method of the red mud after acidifying: stir in the mixer (1) input of the batching of red mud mixture operated, then dilute sulfuric acid is slowly added in red mud mixture carry out acidification; (2), by the red mud mixture after acidification, be red mud tablet by twin rollers extruding, thickness≤3 millimeter of red mud tablet; (3) red mud tablet is transported to roasting in swinging drying oven, roasting time is 1 ~ 3 hour, and sintering temperature controls at 250 ~ 350 DEG C, red mud tablet water content≤5% after roasting, red mud tablet after roasting is the red mud semi-finished product after acidifying, and PCm is weight percentage.

4, the batching of red mud tablet is made up of following component by weight percentage: red mud mixture 75 ~ 95% and dilute sulfuric acid 5 ~ 25%.

5, the batching of red mud mixture is made up of following component by weight percentage: red mud 68 ~ 92%, Concave-convex clay rod 5 ~ 30% and magnesia 0.1 ~ 3%.

6, the batching of dilute sulfuric acid is made up of following component by weight percentage: concentration is the concentrated sulfuric acid 1 ~ 25% and the water 75 ~ 99% of 98%, concentration be 98% concentrated sulfuric acid percentage be weight percentage.

The production method of the red mud after acidifying takes first acidifying to carry out compounding ingredient again, sulfuric acid and quick dissolved sodium silicate, polyvinyl alcohol, hydroxypropyl methylcellulose and sodium carbonate generation chemical reaction can be avoided, give full play to raw-material respective characteristic in batching, and obtain complementation, guarantee the red mud inherent quality after acidifying.

According to the needs of product quality, adopt the red mud pH value after sodium carbonate adjustment acidifying, method is simple.

After the acidified process of red mud, red mud pH value controls 6.5 ~ 7.5, can improve the utilization rate of red mud, not only can bring good economic benefit, environmental benefit and social benefit, and can realize turning waste into wealth.

Red mud after acidifying has the high feature of good thixotropy, heat endurance, plasticity, caking property and dry compression.

Red mud after acidifying is applicable to produce construction material, blowing agent and fire product.

Detailed description of the invention

Below in conjunction with embodiment, the invention will be further described:

1, the red mud batching after acidifying is made up of following component by weight percentage: the red mud semi-finished product 96% after acidifying, quick dissolved sodium silicate 2%, polyvinyl alcohol 1.5%, hydroxypropyl methylcellulose 0.5% and sodium carbonate 0%.

The production method of the red mud 2, after acidifying: by abrasive dust in the red mud batching input grinding machine after acidifying, grain fineness≤0.074 millimeter, the powder after abrasive dust is the red mud finished product after acidifying.

3, the half-finished production method of the red mud after acidifying: stir in the mixer (1) input of the batching of red mud mixture operated, then dilute sulfuric acid is slowly added in red mud mixture carry out acidification; (2), by the red mud mixture after acidification, be red mud tablet by twin rollers extruding, thickness≤3 millimeter of red mud tablet; (3) red mud tablet is transported to roasting in swinging drying oven, roasting time is 2 hours, and sintering temperature controls at 280 ~ 320 DEG C, red mud tablet water content≤5% after roasting, and the red mud tablet after roasting is the red mud semi-finished product after acidifying.

4, the batching of red mud tablet is made up of following component by weight percentage: red mud mixture 88% and dilute sulfuric acid 12%.

5, the batching of red mud mixture is made up of following component by weight percentage: red mud 82%, Concave-convex clay rod 16% and magnesia 2%.

6, the batching of dilute sulfuric acid is made up of following component by weight percentage: concentration is the concentrated sulfuric acid 8% and the water 92% of 98%.

Claims (2)

1. the red mud after an acidifying, it is characterized in that, the red mud batching after acidifying is made up of following component by weight percentage: the red mud semi-finished product 90 ~ 98% after acidifying, quick dissolved sodium silicate 0.1 ~ 5%, polyvinyl alcohol 0.1 ~ 5%, hydroxypropyl methylcellulose 0.01 ~ 3% and sodium carbonate 0 ~ 3%;

The half-finished production method of red mud after described acidifying: stir in the mixer (1) input of the batching of red mud mixture operated, then dilute sulfuric acid is slowly added in red mud mixture carry out acidification; (2), by the red mud mixture after acidification, be red mud tablet by twin rollers extruding, thickness≤3 millimeter of red mud tablet; (3) red mud tablet is transported to roasting in swinging drying oven, roasting time is 1 ~ 3 hour, and sintering temperature controls at 250 ~ 350 DEG C, red mud tablet water content≤5% after roasting, and the red mud tablet after roasting is the red mud semi-finished product after acidifying;

The batching of red mud tablet is made up of following component by weight percentage: red mud mixture 75 ~ 95% and dilute sulfuric acid 5 ~ 25%; The batching of red mud mixture is made up of following component by weight percentage: red mud 68 ~ 92%, Concave-convex clay rod 5 ~ 30% and magnesia 0.1 ~ 3%; The batching of dilute sulfuric acid is made up of following component by weight percentage: concentration is the concentrated sulfuric acid 1 ~ 25% and the water 75 ~ 99% of 98%.

2. the production method of the red mud according to claim 1 after acidifying, is characterized in that, by abrasive dust in the red mud batching input grinding machine after acidifying, grain fineness≤0.074 millimeter, the powder after abrasive dust is the red mud finished product after acidifying.