CN100500887C

CN100500887C - Concentration method for iron and boron in low-grade paigeite

Info

Publication number: CN100500887C
Application number: CNB2007101781501A
Authority: CN
Inventors: 张建良; 蔡海涛
Original assignee: University of Science and Technology Beijing USTB
Current assignee: University of Science and Technology Beijing USTB
Priority date: 2007-11-27
Filing date: 2007-11-27
Publication date: 2009-06-17
Anticipated expiration: 2027-11-27
Also published as: CN101157977A

Abstract

An enriched method of iron and boron by using low-grade ferroboron ore pertains to the field of iron-smelting, in particular to an enriched method of iron and boron by using low-grade ferroboron ore, which applies for the exploitation and use of low-grade ferroboron ore. The method is characterized in that the low-grade ferroboron ore of boron content between 5 percent and 10 percent is taken as raw material and is calcined, cracked, grinded, mixed with solid reducer, baked and magnetic-picked to get the boron concentrate power of boron content between 12 percent and 15 percent and the iron concentrate power of iron content between 60 percent and 90 percent. Consequently, the limited resource of boron and iron is sufficiently used, which has great significance for both the society and economic benefit.

Description

The enriching method of iron and boron in a kind of low-grade paigeite

Technical field

The invention belongs to the ironmaking field, relate to the enriching method of iron and boron in the low-grade paigeite, be used for the development and use of low-grade paigeite stone.

Background technology

The boron resource of China is abundanter, by boron trioxide, nearly 1,000,000,000 tons of total resources, but can only account for 1/4th for what industry was adopted, at present, China's original available boron resource is near exhausted, can not satisfy the demand of development and national economy to the boronation chemical product, " running out of grain " is the unavoidable major issue that China's boron industry faces, though the development and use of the low-grade paigeite stone of reserves maximum have obtained significant progress recently, but because technology, cost, the reason of benefit etc. does not also realize industrialization at present, at present to the utilization of low-grade boron ore mainly aspect following two:

1, the ore dressing aspect

Be conceived to ultra-fine ore grinding, because the embedding cloth of ferro-boron is very thin in the ore, concentration effect will carry out ultra-fine ore grinding with ore so will obtain preferably.This sees in present industrial production and is difficult to realize, therefore fails to realize industrialization

2, pyrogenic process separates

Adopt blast-furnace smelting to separate, though this method ferro-boron separating effect is better, the blast furnace production capacity descends, the coke consumption height, and blast furnace lining corroding is serious, and the high use range of product sulfur-bearing is limited, the more important thing is the B of rich boron slag ₂O ₃Active low, can not satisfy the requirement that carbon alkaline process borax is produced, therefore fail to realize suitability for industrialized production steady in a long-term so far

Summary of the invention

The purpose of this invention is to provide the enriching method of iron and boron in a kind of low-grade paigeite, thereby make full use of limited resource of boron and iron resources.

The enriching method of iron and boron in a kind of low-grade paigeite, the low-grade paigeite that it is characterized in that utilizing boron grade 5～10% for raw material through calcining, pulverizing, ore grinding, with addition of solid reductant, roasting, magnetic separation make the smart powder of boron of boracic 12～15% and iron grade at the smart powder of 60～90% iron.

The sintering process flow process is:

1, raw ore loses crystal water and makes it loose easily broken through 700～900 ℃ of calcinings.

2, ore reduction can sieve it by 0.096mm through the ball mill fine grinding.

3, with addition of the reductive agent (coke powder, bituminous coal, hard coal, wood charcoal powder etc.) of ore deposit amount 10～15%, the reductive agent granularity can be sieved by 0.096mm, abundant mixing on mixer.

4, charging thickness 2～3cm, 1150～1300 ℃ of roastings are 20～30 minutes in High Temperature Furnaces Heating Apparatus.

5, the mineral material is through the ball mill ore grinding after the roasting, and its granularity is controlled between 0.096mm sieve and the 0.075mm sieve and is advisable magnetic separation then.

6, choosing back magnetic part is the smart powder of iron of iron grade 60～90%, and nonmagnetic portion is two kinds of useful products of the smart powder of boron of boron grade 12～15%.

For improving the sintering situation, to enhance productivity, the powder that the present invention can also be good with mixing adds suitable caking agent and carries out pressure ball, and the carbon-containing of compacting is 150～200 ℃ of oven dry down.Pelletizing after the oven dry with the charging thickness of 2～3 pelletizings in High Temperature Furnaces Heating Apparatus with 1150～1300 ℃ maturing temperature roasting 15～20 minutes.Pelletizing cooling back fine grinding after the roasting, its granularity is controlled between 0.096mm sieve and the 0.075mm sieve and is advisable, and carries out magnetic separation then.

Adopt adding solid reductant high temperature directly to reduce, poor boron rock can obtain full iron grade at smart powder of 60～90% iron and the smart powder (boron grade 12～15%) of the industrial boron that can directly utilize after the high temperature reduction magnetic separation, thereby make full use of limited resource of boron and iron resources, all there are significant meaning in society and economic benefit.

Description of drawings

Fig. 1 is a powder mine sintering process flow sheet of the present invention

Fig. 2 is a pellet sintering process flow sheet of the present invention

Embodiment

Embodiment 1

To be sent to ball mill after beater grinder is pulverized through the low-grade paigeite after the calcining is milled to and can sieves by 0.096mm, equally coke also is milled to and can sieves by 0.096mm, coke powder with addition of ore weight 10%, mixing is sent into distribution cabins through belt on mixer, with bed thickness is that the thickness of 2～3cm is packed in the rotary hearth furnace, the flow time of mineral aggregate in stove is 30 minutes, the mineral aggregate rotary hearth furnace of slowly flowing through flows into discharge port, deliver to magneticore-dressing plant through the cooling ore grinding and carry out magnetic separation, choosing back magnetic thing is the smart powder of iron, and nonmagnetics is a boron concentrate.Its composition sees Table 1:

Table 1

Sample number	Nonmagnetics boron content (%)	The full iron of magnetic thing (%)	Maturing temperature (℃)	Roasting time (min)
Sample number	Nonmagnetics boron content (%)	The full iron of magnetic thing (%)	Maturing temperature (℃)	Roasting time (min)	1	12.12	60.67	1150	30
2	13.29	76.51	1200	30	1	12.12	60.67	1150	30
2	13.29	76.51	1200	30	3	14.05	76.79	1250	30
4	14.45	88.49	1300	30	3	14.05	76.79	1250	30

As can be seen from the above table with the rising of maturing temperature, the content of nonmagnetic portion boron also progressively increases, the full iron of magnetic part also raises with the rising of maturing temperature, find out thus, ferro-boron can well separate in this temperature range, magnetic part can be used as the high-quality iron ore and removes blast furnace ironmaking and be utilized, and nonmagnetic portion can be used as the industrial chemicals of producing borax or boric acid, thereby has realized the comprehensive utilization of poor paigeite.

Embodiment 2

To be sent to ball mill after beater grinder is pulverized through the low-grade paigeite after the calcining is milled to and can sieves by 0.096mm, equally coke also is milled to and can sieves by 0.096mm, coke powder with addition of ore weight 10%, mixing is sent into through belt and is made the ball workshop and carry out pressure ball oven dry on mixer, the intensity of ball can not get final product in rotary hearth furnace with it in efflorescence, then with the roasting 20 minutes of packing in the rotary hearth furnace of the bed thickness of 2～3 balls, discharging cooling back ore grinding carries out magnetic separation then, the smart powder of choosing back iron and smart grade powder of boron such as table 2:

Table 2

Sample number	Nonmagnetics boron content (%)	The full iron of magnetic thing (%)	Maturing temperature (℃)	Roasting time (min)
Sample number	Nonmagnetics boron content (%)	The full iron of magnetic thing (%)	Maturing temperature (℃)	Roasting time (min)	1	12.52	60.23	1150	20
2	13.38	76.35	1200	20	1	12.52	60.23	1150	20
2	13.38	76.35	1200	20	3	13.88	76.51	1250	20
4	14.50	89.49	1300	20	3	13.88	76.51	1250	20

Show from above two that the grade of the smart powder of iron and the smart powder of boron is more or less the same after the roasting as can be seen, just carbon containing asks group shorter directly into the stove roasting than fine ore on the roasting time, certainly, it has also increased the technology of making ball, and the pelletizing after the roasting wants big on the energy consumption of ore grinding.Each factory can select to be fit to the operational path of our factory according to the practical situation of our factory.

Claims

1. the enriching method of iron and boron in the low-grade paigeite, the low-grade paigeite that it is characterized in that utilizing boron grade 5～10% for raw material through calcining, pulverizing, ore grinding, make the smart powder of boron of boracic 12～15% and iron grade at the smart powder of 60～90% iron with addition of solid reductant, roasting, ore grinding, magnetic separation;

The sintering process flow process is divided into 2 kinds of powder and pelletizings, and the powder calcination process flow process is:

(1) raw ore loses crystal water through 700～900 ℃ of calcinings;

(2) ore reduction can sieve it by 0.096mm through the ball mill fine grinding;

(3) with addition of the solid reductant of ore deposit amount 10～15%, the reductive agent granularity can be sieved by 0.096mm, mixing on mixer;

(4) charging thickness 2～3cm, 1150～1300 ℃ of roastings are 20～30 minutes in High Temperature Furnaces Heating Apparatus;

(5) the mineral material is through the ball mill ore grinding after the roasting, and its granularity is controlled between 0.096mm sieve and the 0.075mm sieve, magnetic separation then; Choosing back magnetic part is the smart powder of iron of iron grade 60～90%, and nonmagnetic portion is two kinds of useful products of the smart powder of boron of boron grade 12～15%.

2. the enriching method of iron and boron is characterized in that described solid reductant in a kind of low-grade paigeite as claimed in claim 1, employing be coke powder, coal dust and wood charcoal powder.

3. the enriching method of iron and boron in a kind of low-grade paigeite as claimed in claim 1 is characterized in that technical process is for pellet sintering: the powder that mixing is good adds caking agent and carries out pressure ball, and the carbon-containing of compacting is 150～200 ℃ of oven dry down; It is 2～3 pelletizings that pelletizing after the oven dry is gone into the furnace charge layer thickness, and maturing temperature is 1150～1300 ℃, and roasting time is 15～25min, and pelletizing is controlled between 0.096mm sieve and the 0.075mm sieve through the cooled grinding particle size of roasting.