CN102351447A

CN102351447A - Processing method for improving setting performance of desulfurized gypsum

Info

Publication number: CN102351447A
Application number: CN2011101839284A
Authority: CN
Inventors: 夏强
Original assignee: Hohai University HHU
Current assignee: Hohai University HHU
Priority date: 2011-07-02
Filing date: 2011-07-02
Publication date: 2012-02-15
Anticipated expiration: 2031-07-02
Also published as: CN102351447B

Abstract

The invention discloses a processing method for improving the setting performance of desulfurized gypsum. The processing method is characterized by comprising the following steps of: carrying out sample analysis on calcined gypsum, adding 3-5 wt% of fly ash and 0.5-1.5 wt% of CaO when the content of residual CaSO4.2H2O in the calcined gypsum is greater than or equal to 5%, maintaining the temperature at 70-90 DEG C, stirring and tumbling gypsum every day, naturally cooling gypsum after two days until the temperature is below 40 DEG C; or adding 3-5 wt% of fly ash if residual CaSO4.2H2O content in the calcined gypsum is less than 5% after the sample analysis, maintaining the temperature at 40-60 DEG C, carrying out one-time spraying every day to increase the bunker humidity, stirring and tumbling gypsum, naturally cooling gypsum after three days until the temperature is below 40 DEG C. By the adoption of the processing method, the desulfurization setting performance can be raised, the setting time of gypsum can be prolonged, the initial setting time is prolonged from original around 4 minutes to around 8 minutes, and the operation time of gypsum is prolonged.

Description

A kind of condense working method of performance of desulfurated plaster of improving

Technical field

The present invention relates to a kind of aging method of desulfurated plaster, improve the desulfurated plaster aging method of performance that condenses thereby specifically relate to a kind of admixture that adds.

Background technology

Flue gas desulfurization technique is to control one of technology that sulfur dioxide emissions are the most effective and application is the widest at present.China begins the flue gas desulfurization demonstration project in early 1990s, and the desulfurization industry obtains fast development after 2002.Consequent a large amount of desulfurized gesso of flue gas, its quality can match in excellence or beauty with the plaster of paris, is a kind of extraordinary building resource.But compare with common gypsum, desulphurization building gypsum is faster time of coagulation, and the unstable properties of condensing, and causes very big difficulty for the gypsum base Part Quality Control.

The ageing of gypsum can make complete in crystal formation, and it is big and pure that crystal grain becomes.Make generation thing phase change in the plaster of Paris through ageing; Can be under the condition of certain temperature with the dihydrate gypsum of underburnt; Continue dehydration and change into semi-hydrated gypsum, also can make dehydrated gyp-III overbumt and dehydrated gyp-II absorb the inner or extraneous water transform of the plaster of Paris and form semi-hydrated gypsum through certain hour.Through suitable ageing process, can make the interior thing of gypsum stable mutually, overall performance improves.

Present varied, the different ageing process of aging method of gypsum, the performance of gypsum be difference to some extent also.General aging method, although all can improve the gypsum performance to a certain extent, the time of coagulation of moulding requirement, especially desulphurization building gypsum that often still is difficult to satisfy gypsum base material is very short, degree of mobilization through the time loss big, operable time is just very of short duration.

Summary of the invention

The objective of the invention is to have overcome deficiency of the prior art, a kind of control simple to operate, easy is provided, what prolong gypsum time of coagulation improves the condense working method of performance of desulfurated plaster.

The technical scheme that the present invention adopts is following:

A kind of condense working method of performance of desulfurated plaster of improving is characterized in that its step is following:

To the gypsum sampling analysis after the calcining, as residual CaSO wherein ₄﹒ 2H ₂O>=5% o'clock adds the flyash and the CaO of 0.5-1.5% mass ratio of 3-5% mass ratio, and holding temperature is at the 70-90 degree, and stirs and the gypsum that rolls every day, makes gypsum naturally cool to 40 two days later and gets final product below spending;

If behind the sampling analysis, obtain wherein residual CaSO ₄﹒ 2H ₂O content＜5%, the flyash of admixture 3-5% mass ratio therein then, holding temperature is at the 40-60 degree, and taking every day once to spray increases feed bin humidity, and stirs and the gypsum that rolls, and gypsum is got final product below naturally cooling to 40 degree.

The scheme of selecting of the present invention is to the gypsum sampling analysis after the calcining, as residual CaSO wherein ₄﹒ 2H ₂O>=5% o'clock adds the flyash of 4% mass ratio and the CaO of 1% mass ratio, and holding temperature is spent every day 80 and stirred and the gypsum that rolls.

To the gypsum sampling analysis after the calcining, as residual CaSO wherein ₄﹒ 2H ₂O content＜5% o'clock, the flyash of admixture 4% mass ratio therein then, holding temperature is spent every day and taked once to spray 50 increases feed bin humidity, and stirs and the gypsum three days of rolling.

Compared with prior art, the invention has the beneficial effects as follows:

Adding flyash etc. during ageing forms and grain composition as the crystalline phase that admixture can effectively improve desulfurated plaster; Improve its performance of condensing; Prolong the time of coagulation of desulfurated plaster, its presetting period has extended to about 8 minutes by original about 4 minutes, obtains long gypsum operable time.And the present invention does not need very high plant area's condition, and is simple to operate, easily control.

Embodiment

Below in conjunction with specific embodiment the present invention is described in further detail:

Embodiment:

At first calcining desulfurated plaster is later taken a sample, carry out material phase analysis, if residual CaSO in the desulfurated plaster ₄﹒ 2H ₂O>=5%; Then terra alba is placed in the airtight feed bin immediately; The flyash of admixture calcined gypsum 3%-5% mass ratio and the CaO of 0.5-1.5% mass ratio; Holding temperature is spent between 90 degree 70; Stirred and rolled gypsum 1 time in per 12 hours; Operation is 2 days total time, promptly stirs altogether and the gypsum 4 times of rolling.The 3rd angel's gypsum can use below naturally cooling to 40 degree.

If CaSO ₄﹒ 2H ₂O content＜5%; Then terra alba is put into airtight feed bin immediately; The flyash of admixture terra alba 3%-5% mass ratio; Holding temperature is spent between 60 degree 40; Taking every day once to spray increases feed bin humidity; Stirred and rolled gypsum 1 time in per 12 hours, operation is 3 days total time, promptly stirs altogether and the gypsum 6 times of rolling.The 4th angel's gypsum can use below naturally cooling to 40 degree.

Preferred version of the present invention is to behind the gypsum sampling analysis after the calcining, like residual CaSO wherein ₄﹒ 2H ₂O>=5% o'clock then adds the flyash of 4% mass ratio and the CaO of 1% mass ratio, and holding temperature is spent every day 80 and stirred and the gypsum that rolls.As residual CaSO wherein ₄﹒ 2H ₂O content＜5% o'clock, the flyash of admixture 4% mass ratio therein then, holding temperature is spent every day and taked once to spray 50 increases feed bin humidity, and stirs and the gypsum three days of rolling.

The desulfurated plaster powder that the present invention processes through preferred version in use; About 8 minutes of its presetting period; Scheme outside the preferred version can make the presetting period of desulfurated plaster reach 7 minutes; And adopt the desulfurated plaster presetting period before the inventive method processing only not have an appointment 4 minutes, thereby adopt the present invention and process the back desulfurated plaster presetting period and can reach the level of common gypsum.

The undeclared part of other that relates among the present invention is identical with prior art.

Claims

1. one kind is improved the condense working method of performance of desulfurated plaster, it is characterized in that its step is following:

2. a kind of condense working method of performance of desulfurated plaster of improving according to claim 1 is characterized in that: to the gypsum sampling analysis after the calcining, as residual CaSO wherein ₄﹒ 2H ₂O>=5% o'clock adds the flyash of 4% mass ratio and the CaO of 1% mass ratio, and holding temperature is spent every day 80 and stirred and the gypsum that rolls.

3. a kind of condense working method of performance of desulfurated plaster of improving according to claim 1 is characterized in that: to the gypsum sampling analysis after the calcining, as residual CaSO wherein ₄﹒ 2H ₂O content＜5% o'clock, the flyash of admixture 4% mass ratio therein then, holding temperature is spent every day and taked once to spray 50 increases feed bin humidity, and stirs and the gypsum three days of rolling.