CN1115309C

CN1115309C - Flyash treating method

Info

Publication number: CN1115309C
Application number: CN00112311A
Authority: CN
Inventors: 蒋兆广
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-05-31
Filing date: 2000-05-31
Publication date: 2003-07-23
Anticipated expiration: 2020-05-31
Also published as: CN1274693A

Abstract

The present invention relates to a method for treating coal fly ash, which is used for cement and concrete. The present invention has the process steps that raw materials are composed of 10 to 25 % of CaO, 2.5 to 10% of plaster (measured by SO3), 65 to 87.5% of coal fly ash, and 0 to 5% of zeolite according to the total weight proportion; a mixture is sufficiently and uniformly stirred; a blank with the certain size can be manufactured; the maintenance is carried out at the normal temperature; the temperature rises to 700 to 900 DEG C, and a product is formed by cooling. The present invention has the advantages that the crystalloid difference is formed by being conducted by proper water and being calcined at a suitable temperature rise speed, has high dispersing degree, and can form a mixture body which has small adhesive force among mineral materials and is easily ground. The mixture body is ground with cement clinker or can replace partial cement produced concrete after the mixture body is ground so that the cement hydration can be promoted, and the hydration mineral performance can be improved.

Description

The treatment process of flyash

What the present invention relates to is a kind of treatment process to flyash, and the flyash after the processing can be used in cement and the concrete, and it belongs to the technical field that material of construction is produced cement raw material.

Prior art, as CN1165792, claim in its specification sheets: it is a kind of to improve the activity of flyash, make it to accelerate to become cement mixture with the speed of response of calcium hydroxide, starting material semi-hydrated gypsum wherein is defined as 1-4%, adopt compression moulding technology in the production technique, need 2-4 hour insulation after the calcining, the size of piece material is the brick type, the finished product that forms speeds up influential to hydrated cementitious, and can not form and contain silicate hydratable calcium aluminite sosoloid, thereby the development of cement early strength is had certain influence.

The objective of the invention is to defective at above-mentioned existence, a kind of new flyash treatment process that is used for cement and concrete is proposed, raw material can adopt industrial residue fully, do not produce secondary pollution, finished product can effectively improve the stability and the cement strength of cement cementitious performance and cement stone, can also quicken the early hydration speed of cement, thereby improve cement early strength, and guarantee the later strength development.

Technical solution of the present invention: processing step branch (1) starting material and proportioning thereof contain the industrial residue of Ca (OH) 2 such as acetylene gas slag, CaO or Ca (OH) 2 at interior material; Contain chemical gypsums such as water or anhydrous calciumsulphate, phosphogypsum or citric acid gypsum; Wet row of heat power plant or dry discharge fly ash; The soft zeolite that plasticity is arranged.The ratio that they respectively account for its gross weight is as follows: account for 10-25% in CaO and the CaO that comprises other material substitution, gypsum is in SO3, and the SO3 that comprises other material substitution accounts for 2.5-10%, flyash accounts for 65-87.5%, compliant soft zeolite accounts for 0-5%, (2) add 30% the water uniform mixing account for above-mentioned starting material total amount, (3) make the base of cm (30-50) cm of (6-10) cm * (8-14), natural curing, (4) heat in the kiln internal combustion, with 10-20 hour the temperature in the kiln is risen to about 500 ℃, and then the temperature in the kiln is risen to 700 ℃-900 ℃ with 2-6 hour, stop to heat (5) cooling finished product (the flyash product after the processing) immediately.

Advantage of the present invention: formed the high anhydrous mineral of dispersity in the flyash product after the processing and gone back enhydrite on a small quantity, it in cement can and the interaction of calcium speed up, produce gelling preferably, and dispersity high more action effect is just good more.Therefore, the flyash after the processing can improve cement cementitious performance.

Flyash product after the processing includes the fine silica powder characteristic, and an amount of silica flour can reduce the content of hydroxyl calcium stone in the cement stone in cement, increases the composition of hydrated calcium silicate, improves the stability of cement stone.

Contain the mineral that the dewatered aquation of part is crossed in the flyash product after the processing, because calcining temperature is lower, these mineral and the new crystallizable mineral degree that forms are poor, meet the very fast recovery of water, form the aquation small-crystalline, handle the aquation mineral that do not lose water in the flyash in addition fully, grinding is distributed to and also forms small-crystalline in the cement, and these small-crystallines will constantly be grown in hydrated cementitious and be grown up, this cement clinker particle aquation of just inducing, so the flyash after handling can quicken hydrated cementitious

Flyash product after the processing is the consumption that as far as possible reduces calcium under possible situation, and its calcium silicon ratio is generally below 1.0.The height of the sial activity in cement of the flyash after the processing, dispersity is big, be directly unapproachable with means such as grindings, and containing suitable vitriol in handling flyash exists, these aquation mineral that just make the cement that contains the flyash product after the processing form are more reasonable, the result improves cement strength, more is rich in weather resistance.

Embodiment 1 (the raw material gross weight is 1000 kilograms)

Replace the grog pulverizing cement with the flyash product after the suitable processing, come comparison with same grinding condition, add the cement of the flyash after the processing, the resistance to compression of the same period and folding strength can add the cement that gypsum grinds greater than skillful material.Table one data are exactly good example.Flyash accounts for 65% of weight, phosphogypsum accounts for 12% of weight, carbide slag (acetylene gas slag) accounts for 18% of weight, soft zeolite accounts for 5% of weight, add 30% the water uniform mixing account for above-mentioned starting material total amount again, make the base of 10cm * 12cm * 40cm, natural curing (sun-proof anti-drench with rain greatly) reaches 880 ℃ to kiln temperature and promptly cools off with burning in about 15 hours in kiln.We are from the situation of table one strength development, and with the cement of the flyash after handling, strength growth rate is higher than by grog and adds the cement that gypsum grinding comes out after 7 days, this shows that it is bigger adding the strength of cement growth potential of handling flyash.

Embodiment 2 (the raw material gross weight is 1000 kilograms)

The result that flyash product after the processing is made in the laboratory is more satisfactory, in big production effect is preferably arranged also.Table two (is handled flyash production; Flyash accounts for 70% of weight, and 10%. carbide slags that citric acid gypsum accounts for weight account for 20% of weight, adds 30% the water uniform mixing account for above-mentioned starting material total amount again, makes 30 centimetres of bases of 8 cm x, 16 cm x and is warming up to 900 ℃ of just coolings through 18 hours.Compare with certain factory's practical condition, original No. 425 Portland fly ash cements of producing of this factory, the grog of doing is about 68%, and used flyash product after handling, only use 50% grog, continuous three numbering average intensity only is higher than with 68% grog value with 50% clinker strength value from table.Therefore can conclusion, it is resultful producing cement with the flyash after the partially disposed as blended material.

Embodiment 3: since flyash after handling and grog together the pulverizing cement effect be good, then behind the grinding in the pulverized fuel ash cement after not adding processing instead of part cement also be that good effect is arranged certainly, to saving your breath with the flyash replacement cement after an amount of the processing, sand oar intensity can remain unchanged.Table three (used processing flyash technology is the same) institute's column data is exactly the flyash replacement cement testing situation comparison with 15% treated grinding, from Biao Kede, replace cement that the original intensity of cement is remained unchanged with 15% processing flyash, and can suitably increase through grinding.

Table one, the flyash after the processing (handling ash) relevant physicals in cement

Numbering	Grog %	Natural dihydrate gypsum %	Handle grey %	Fineness %	The initial set time-division	The final set time-division	Ultimate compression strength (Mpa)			Folding strength (MPa)
							Ultimate compression strength (Mpa)			Folding strength (MPa)			3 days	7 days	28 days	3 days	7 days	28 days
							D 1	9 6	4	-	4. 6	1：40	3 days	7 days	28 days	3 days	7 days	28 days	2：3 5	34. 3	49. 1	57. 8	6. 3	7. 1	8. 4
D 2	7 6	4	2 0	3. 1	1：40	3：1 0	D 1	9 6	4	-	4. 6	1：40	40. 1	54. 6	63. 8	6. 6	7. 9	9. 1	2：3 5	34. 3	49. 1	57. 8	6. 3	7. 1	8. 4
D 2	7 6	4	2 0	3. 1	1：40	3：1 0	D 3	5 7	3	4 0	3. 0	1：50	40. 1	54. 6	63. 8	6. 6	7. 9	9. 1	3：2 5	33. 6	45. 4	57. 5	5. 4	6. 9	8. 4

Table two, the flyash after the processing (handling ash) Applied Physics performance situation in the big production of cement

Numbering

Grog %

Natural two water stones

Flyash %

Handle grey %

Platform product ton/hour

Fineness %

The initial set time-division

The final set time-division

Ultimate compression strength (MPa)

Folding strength (Mpa)

									3 days	7 days	28 days	3 days	7 days	28 days
									3 days	7 days	28 days	3 days	7 days	28 days	A- 40-43	68	4	2 8	-	14	4. 1	3： 10	4： 20	26. 7	36. 1	50. 2	4. 8	5. 9	7. 6
A- 44- 46	50	3	3 2	1 5	16	4. 1	2： 20	3： 30	29. 8	40. 8	55. 8	5. 4	6. 6	8. 4	A- 40-43	68	4	2 8	-	14	4. 1	3： 10	4： 20	26. 7	36. 1	50. 2	4. 8	5. 9	7. 6

Table three replaces cement sand oar strength ratio with the flyash after 15% processing (handling ash)

Numbering	Portland cement %	Slag cement %	Mixed cement %	Grinding is handled grey %	Ultimate compression strength (MPA)			Folding strength (MPA)
					Ultimate compression strength (MPA)			Folding strength (MPA)			3 days	7 days	28 days	3 days	7 days	28 days
					D6 8	100	-	-	-	28 .4	3 days	7 days	28 days	3 days	7 days	28 days	38 .6	52 .6	5. 0	6. 1	7.6
D6 9	85	-	-	15	D6 8	100	-	-	-	28 .4	29 .6	39 .8	54 .1	5. 2	6. 4	7.8	38 .6	52 .6	5. 0	6. 1	7.6
D6 9	85	-	-	15	D7 0	-	100	-	-	27 .8	29 .6	39 .8	54 .1	5. 2	6. 4	7.8	38 .9	54 .0	4. 8	6. 0	7.8
D7 1	-	85	-	15	D7 0	-	100	-	-	27 .8	28 .4	39 .6	54 .9	5. 0	6. 2	8.4	38 .9	54 .0	4. 8	6. 0	7.8
D7 1	-	85	-	15	D7 2	-	-	100	-	28 .2	28 .4	39 .6	54 .9	5. 0	6. 2	8.4	38 .6	52 .8	4. 9	6. 1	7.5
D7 3	-	-	85	15	D7 2	-	-	100	-	28 .2	28 .3	38 .5	53 .0	4. 9	6. 0	7.5	38 .6	52 .8	4. 9	6. 1	7.5

Flyash comprise flyash inferior after treatment in cement and concrete effect be good, we can say in cement, to use and started a new way again for the development powder coal ash.

Claims

1, handles the method for flyash, it is characterized in that processing step branch (1) starting material and proportioning thereof, contain Ca (OH) ₂Industrial residue acetylene gas slag, CaO or Ca (OH) ₂At interior material; Contain water or anhydrous calciumsulphate, phosphogypsum or citric acid gypsum; Wet row of heat power plant or dry discharge fly ash; The ratio that they respectively account for its gross weight is as follows: account for 10-25% in the CaO amount of allocating into, gypsum is with SO ₃The meter amount of allocating into accounts for 2.5-10%, flyash accounts for 65-87.5%, (2) add 30% the water uniform mixing account for above-mentioned starting material total amount, (3) make the base of cm (30-50) cm of (6-10) cm * (8-14), natural curing, (4) heat in the kiln internal combustion, with 10-20 hour the temperature in the kiln is risen to about 500 ℃, and then the temperature in the kiln is risen to 700 ℃-900 ℃, stop immediately heating with 2-6 hour, (5) cooling, finished product.