CN103408235A

CN103408235A - Powder forming adhesive

Info

Publication number: CN103408235A
Application number: CN2013103613648A
Authority: CN
Inventors: 闵敏
Original assignee: Individual
Current assignee: Individual
Priority date: 2013-08-19
Filing date: 2013-08-19
Publication date: 2013-11-27

Abstract

The invention provides a powder forming adhesive. The powder forming adhesive is prepared from the following raw materials in percentage by weight: 85-90% of bentonite, 5-10% of pregelatinized starch and 5-10% of hydroxypropyl methylcellulose. The powder forming adhesive has the following advantages: in a production process of sludge pellets forming in steelmaking plants, after the adhesive is used, moisture in sludge does not need to be controlled in the production process, and even more moisture exists in the sludge, the sludge can not be adhered to a mold, so that the demolding is relatively convenient, and the demolding rate can reach 95%; after the adhesive is mixed into the sludge pellets, a net structure is formed and wraps the sludge powder, so that the strength of the sludge pellets is substantially improved and can be up to 120kg/cm<2>; the mixing rate of the powder forming adhesive in the sludge pellets is low, so that more impurities are reduced, and the impurity removal in a steelmaking technology is facilitated; after the powder forming adhesive is used, 10% of moisture can be squeezed out by using forming equipment in the forming process of the sludge pellets, so that the cost is saved for the drying treatment of the pellets in a later period.

Description

A kind of powder compacting caking agent

Technical field

The present invention relates to a kind of powder compacting caking agent, belong to the macromolecular material chemical field.

Background technology

It is by pulverous mud that the mud tailings of steel-making re-uses, and is made into spherically or block, then enters calcining in shaft furnace.Traditional method is mainly to adopt the ceramic bonding mud such as inorganic bentonite or cement, lime, makes the mud moulding.But, due to the singularity of mud, use conventional binders can face following problem in process of production:

1, moisture is difficult to control, and is difficult for the demoulding.Owing in mud, containing a large amount of moisture, moisture content is at 25%-30%, and after mixing binding agent, binding agent can stick on forming mould equally, and causing can't the demoulding, and impact is produced continuously.The method that existing mud pellet formation adopts is to control moisture, allows binding agent be in half water suction state, make viscosity reach can just the demoulding state.But so not only to production technique require too high, careless slightly will the demoulding, and the binding agent of the state that partly absorbs water can't bring into play his normal viscosity, is easy to fragmentation after having taken off mould, reduces balling ratio, the demolding rate of existing mud pellet formation can only reach 65%.

2, viscosity is low, mixes than height.Conventional binders will make the mud moulding, mixes to make a gesture of measuring at least to reach 8%-10%.Mixed ratio is excessive, causes pelletizing impurity too high, for follow-up smelting brings more problem.

3, intensity is not high, easily broken.Control the mud pelletizing that moisture is produced, because binding agent is in half water suction state, can't adhere to the mud powder fully.So in process of production, very little external force just can make pelletizing break.And the physical structure of this material of mud own is more special, conventional binders is not high to the affinity of sludge material.Use conventional adhesive, 10% mix made a gesture of measuring, and the pressure of 5 kg/cm just can make undried pelletizing cracked.Dried pellet strength also can only reach 20 kg/cm.

In sum, due to the singularity of moisture and self material of mud, produce the problem that the producer of mud pelletizing runs into: produce continuously, can only adopt the binding agent that viscosity is low or control moisture, make a gesture of measuring greatly but can produce to mix, impurity is high, the problem that intensity is not high.Do not control moisture, just be difficult for the demoulding, balling ratio is low, can't produce continuously.

Summary of the invention

For the problems referred to above, the purpose of this invention is to provide a kind of easy demoulding, the powder compacting caking agent that intensity is high.

A kind of powder compacting caking agent of the present invention comprises the raw material of following weight percent: wilkinite 85-90%, pre-gelatinized starch 5-10%.

A kind of powder compacting caking agent also comprises Vltra tears 5-10%.

Above-mentioned each raw material plays in producing the mud pelletizing effect is as follows: rear generation viscosity, for feather fractures, is being combined in the wilkinite surface with water, the small-sized particle around adhering to.Intensity is very high after drying, in pelletizing as main framework material.Pre-gelatinized starch is polymer chain structure, a lot of little side chains are arranged on main chain, with water, be combined the mutual hook of rear side chain, with wilkinite, form reticulated structure between the polymer side chain, because the mud powder particle is relatively large, so the mud powder is wrapped and is fixed in this reticulated structure.Water molecules is very little, so water molecule energy is by this reticulated structure.When the extruding that is subject to forming mould, a large amount of water is extruded pelletizing inside, so faster dry pelletizing.Side chain forms a kind of reticulated film on the pelletizing surface, and the structural capacity between netted side chain is much larger than the adhesive power of side chain to die surface, so the easily demoulding.After using this binding agent, in production process, no longer need to control moisture, demolding rate is just more than 95%.Reticulated structure because wilkinite and pre-gelatinized starch form, have larger stress when being subject to external force, only can be out of shape and be difficult for breaking, thereby improve the pelletizing bulk strength.Vltra tears is as the enhancement type macromolecular material, and the carbon in mud is combined, and can form a staggered reticulated structure with the reticulated structure of profit soil and pre-gelatinized starch after drying, can greatly improve the pelletizing bulk strength after drying.

The present invention has following advantage: carry out in the production of mud pelletizing moulding at steelworks, use this caking agent not need in process of production to control the moisture in mud, even in mud, there is much more again moisture also can not stick on mould, can the more convenient demoulding, demolding rate can reach 95%; After this binding agent is incorporated in the mud pelletizing, form reticulated structure, the mud powder packets is wrapped, significantly improve the intensity of mud pelletizing, intensity is the highest can reach 120 kg/square centimeter; This binding agent mixing than low in the mud pelletizing, reduce more impurity, is convenient to removal of impurities in process for making; After using this binding agent, in the process of mud pelletizing moulding, by molding device, can squeeze out 10% moisture, for the drying treatment of later stage pelletizing cost-saving.

Embodiment

The following examples can illustrate in greater detail the present invention, but do not limit in any form the present invention.

Embodiment 1: to only needing rapid, high volume production, to the not high manufacturer of mud pelletizing requirement of strength, can only adopt two kinds of composition of raw materials of wilkinite and pre-gelatinized starch, above-mentioned two kinds of raw materials by weight are taken: wilkinite 90%, pre-gelatinized starch 10%, then mix and get final product.The binding agent of this formula is incorporated in the mud of steel-making in 5% ratio, and the intensity of the not dry pelletizing of producing is 15 kg/cm, and the intensity of dry pelletizing is 35 kg/cm.

Embodiment 2: to the mud pellet strength manufacturer that has certain requirements, adopt wilkinite, pre-gelatinized starch and three kinds of composition of raw materials of Vltra tears, above-mentioned raw materials is taken by weight percentage: wilkinite 85%, pre-gelatinized starch 10%, Vltra tears 5%, then mix and get final product.The binding agent of this formula is incorporated in the mud of steel-making in 3% ratio, and the intensity of the not dry pelletizing of producing is 15 kg/cm, and the intensity of dry pelletizing is 35 kg/cm.The binding agent of this formula is incorporated in the mud of steel-making in 5% ratio, and the intensity of the not dry pelletizing of producing is 20 kg/cm, and the intensity of dry pelletizing is 90 kg/cm.

Claims

1. a powder compacting caking agent, is characterized in that: the raw material that comprises following weight percent: wilkinite 85-90%, pre-gelatinized starch 5-10%.

2. a kind of powder compacting caking agent according to claim 1, is characterized in that: in raw material, also comprise Vltra tears 5-10%.