CN102701619A

CN102701619A - Technology making use of waste phosphogypsum to produce gypsum block

Info

Publication number: CN102701619A
Application number: CN201110074895XA
Authority: CN
Inventors: 石磊
Original assignee: LULINGRUNFA CHEMICAL CO Ltd JIANGSU
Current assignee: LULINGRUNFA CHEMICAL CO Ltd JIANGSU
Priority date: 2011-03-28
Filing date: 2011-03-28
Publication date: 2012-10-03

Abstract

A technology making use of waste phosphogypsum to produce gypsum blocks comprises the steps of processing the waste phosphogypsum by a raw material room, and carrying out the sections of rotary drying and mixed pressing respectively after purification. The phosphogypsum is made into building gypsum packaged finished products after rotary drying, grinding and cooling, and is made into retarder finished products after crushing, cooling and balling. In the mixed press section, the purified phosphogypsum is mixed with the building gypsum, a complexing agent and an accelerating agent. The phosphogypsum is stirred with water and additives, then pressed to blocks, and high-temperature steamed to get finished products.

Description

A kind of technology of utilizing discarded phosphogypsum production gypsum block

Technical field

The present invention relates to a kind of technology of production gypsum block, be specifically related to a kind of technology of utilizing discarded phosphogypsum production gypsum block.

Background technology

Industrially developed country such as Europe, U.S.A, day pay much attention to the comprehensive utilization of industry by-product gypsum.To being that the research that raw material is processed plaster of Paris gets into the stage of maturity with the phosphogypsum, can complete proposition one cover process production techniques and equipment, the plaster of Paris of processing can be superior to or be the plaster of Paris of raw material with equaling with the plaster of paris.Like countries such as Japan, Germany, the U.S., utilize sophisticated technology to build up tens of the production lines of multiple scale, produce qualified plaster of Paris, and then process various plasterings.Germany is the chemical gypsum research and development and uses the most flourishing country, is to adopt chemical gypsum to produce the country of plasterboard the earliest, and annual nearly 1,000,000 tons of phosphogypsums are processed brushing gypsum plate and Thistle board.Japan is the most successful country of industry by-product gypsum utilization, and its chemical gypsum quality is fine, and since 1997, almost all the by-product industrial gypsum all was used to produce plasterboard, and annual nearly 2,000,000 tons of phosphogypsums are processed Thistle board.France also payes attention to the application of phosphogypsum, and every year, also nearly 1,000,000 tons of phosphogypsums were processed brushing gypsum and Thistle board.State such as Britain and Holland then utilizes chemical gypsum to produce a type semi-hydrated gypsum and anhydrite, is used to produce thorough of auto-flowing floor and gypsum building.

Be that the technology of main material production building block mainly contains two kinds with the waste material phosphogypsum in the prior art, a kind of is that phosphogypsum carries out frying earlier, and then adds industrial waste compression mouldings such as sand or slag by certain proportioning; Another kind is that phosphogypsum is mixed the back compression molding with cement, sand etc.Adopt the building block of these two kinds of fabrication techniques, the ultimate compression strength that technical the most insufficient place is building block is lower, generally only reaches 4.5～7.5MPa, and the intensity quality of product is also unstable, is difficult to adapt to the requirement of modern architecture to material of construction.

Summary of the invention

The present invention is directed to above-mentioned weak point, studied a kind of technology of utilizing discarded phosphogypsum production gypsum block, purpose is to reduce to greatest extent the wasting of resources and environmental pollution.

Technical solution of the present invention:

A kind of technology of utilizing discarded phosphogypsum production gypsum block is that raw material passes through the production of plaster of Paris and the production of cement setting retarder with discarded phosphogypsum, and final production goes out gypsum block, it is characterized in that:

The process step of said plaster of Paris is:

A. foreign material such as the rubble that is mixed in the raw material, grass bits, tree fork are laggard goes in the batch can through screening out at first will to discard phosphogypsum.

B. the discarded phosphogypsum in the batch can is added water and clean, once more discarded phosphogypsum is sieved with 60 purpose vibratory screening apparatuss then.

C. the discarded phosphogypsum that sieves through second step concentrates by being pumped in the hydrocyclone, and concentrate feed is cleaned once more.

D. cleaning the rare water of discarded phosphogypsum (fineness≤45 ü) later and get into neutralization tank and add the alkali neutralization, then rare water is sent into vacuum hydroextractor and dewater, is the phosphogypsum after≤25% the purification for water cut after the vacuum hydro-extraction.

E. send into the kiln hood storehouse by the phosphogypsum of endless belt conveyor after with the purification of water ratio≤25%; Evenly feed in the direct type rotary dryer through disk feeder, measuring belt machine, gypsum transfer roller; Wet phosphogypsum in the direct type rotary dryer with vapor heat exchanger in hot blast directly carry out heat exchange; Make free water evaporates, form dry phosphogypsum powder.

F. the phosphogypsum powder after the oven dry directly adds the drawing-in device of the water trap that seethes with excitement through machine for zipper, chapelet, phosphogypsum through with the hot blast indirect exchange, slough 1.5 parts of crystal water in the gypsum.

G. the phosphogypsum powder after the dehydration all is transported to ball mill grinding through handling equipment, and the plaster of Paris part after the grinding gets into feed bin through handling equipment, is used for the production of cement setting retarder.A part gets into indirect type revolution cooler through transfer roller, and the cooling back is delivered in the plaster of Paris storehouse subsequent use by handling equipment.

The process step of said cement setting retarder is:

The filter cake that produces in the process step d step with plaster of Paris is sent into the kiln hood storehouse through endless belt conveyor; After disk feeder discharging, the metering of measuring belt machine; Evenly feed the direct type rotary dryer by the gypsum transfer roller; Filter cake carries out heat exchange with hot blast in the direct type rotary dryer, make free water evaporates, forms water ratio and is lower than 10% phosphogypsum work in-process.

A. plaster of Paris that produces in the process step g step with plaster of Paris and 10% phosphogypsum work in-process are proportionally with after water mixes; Through mixing conveying, nodulizer balling-up; Form spherical cement setting retarder, through handling equipment cement setting retarder is sent to feed bin, through wrapping machine cement setting retarder is packaged into packed finished product then.

The process step of said gypsum block is:

A. at first water filling in stirrer when water level surpasses 2/3, begins in stirrer, to put into plaster of Paris, recombiner, promotor, and water and phosphogypsum, additive stir in stirrer.

B. the material after will mixing is sent into the slaking storehouse and is carried out digestion reaction, makes its slaking, with the reactive behavior of raising component and the oxious component in the elimination phosphogypsum.

C. open the stirrer upset after slaking is accomplished; Pour the slip that stirs into shaper compacting, treat that calcium plaster has certain intensity after, start Pulp scraping device and scrape the tenon mouth at the building block top; Start the shaper jacking cylinder after the gypsum initial set is accomplished, from shaper, eject building block.

D. the gypsum block after ejecting is sent into steam-cured chamber by dispenser and is carried out vapor cure, and the steam-cured time is 2～10 hours, and steam-cured indoor vapor pressure is 0.1～5MPa.

E. the gypsum block after the steam-cured completion is sent into bead cutter behind roller conveyor conveying, transverse conveyor, lozenge machine, accurately cut to desired size, and production board roller conveyor behind finished product is sent into the stacker stacking, becomes the buttress back to deliver to stockyard by fork truck and stores.

The clear water that vacuum hydroextractor is deviate from the technology d step of said plaster of Paris uses as b, c two step cycle of the technology of plaster of Paris.

The hot blast of phosphogypsum drying machine is that hot blast and the fresh air that heat supply workshop vapor heat exchanger provides produces after heating in the technology a step of said cement setting retarder.

Through the hot cigarette emptying after absorption tower dedusting, desulfurization behind the drying plant, produced simultaneously hot water is used to clean phosphogypsum and uses in the technology a step of said cement setting retarder.

The required thermal source in steam-cured chamber is established a mixing section from interchanger steam in the technology e step of said gypsum block in the steam-cured chamber, and the blended hot blast temperature is 250 ℃; After steam-cured indoor and gypsum block heat exchange; Steam temperature drop to 120 ℃, this moment, partly steam heated in the internal recycle suction pipe stove through carrying out, and the temperature of hot spots wind in the suction pipe stove is added to about 500 ℃; Sent back to mixing section then; Mix with internal recycle wind, form 250 ℃ steam, get into again and go the maintenance gypsum block in the maintaining machine.

Beneficial effect of the present invention: whole production line is an one, does not need the outsourcing raw material, does not need fuel to heat in the gypsum block production process, introduces the steam-cured gypsum block of sulfuric acid production line waste heat, reduces resource consumption, environmentally safe.

Embodiment

Discarded phosphogypsum is handled through the raw material room; Through carrying out rotary drying after the purification respectively and the compacting workshop section that is mixed, get into pulverizing behind the phosphogypsum entering rotary drying and cool off back one-tenth plaster of Paris packaging final prod, get into pulverizing and be cooled to ball formation retardant finished product; Purify phosphogypsum and get into be mixed compacting workshop section and plaster of Paris, recombiner, promotor; Water and phosphogypsum, additive stir, and are pressed into building block then, through finished product behind the high-temperature steam curing.

Claims

1. a technology of utilizing discarded phosphogypsum production gypsum block is characterized in that with discarded phosphogypsum be raw material, makes gypsum block through purification, rotary drying, the compacting that is mixed.

2. according to claim 1, abandon the process that is mixed and the technological design of phosphogypsum production gypsum block production technology.