CN1193000A

CN1193000A - Method of discharging alkaline dregs to make engineering soil

Info

Publication number: CN1193000A
Application number: CN97101180A
Authority: CN
Inventors: 乔希海
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-03-09
Filing date: 1997-03-09
Publication date: 1998-09-16

Abstract

The present invention relates to a method directly treating discharged caustic sludge to prepare engineering soil, belonging to the field of comprehensive utilization of discharged caustic sludge in ammonia-soda process to prepare pure soda. Said invented method is characterized by adding precipitant and other selective ingredients including flyash, cement, liquid-state slag, slag powder, lime, gypsum, loess, sand and sodium silicate to the discharged caustic sludge through such processes as mixing, stirring, sedimentation, discharging liquid, vacuum prepressurizing and dewatering to reduce its water content to obtain the invented finished product.

Description

The method of discharging alkaline dregs to make engineering soil

The invention belongs to the comprehensive utilization of waste liquid in " solvay soda process " the soda ash production process of a kind of relating to.

Before the present invention realizes, produce a large amount of waste liquids, waste residue in " solvay soda process " soda ash production process.The liquid and waste slag produced of these dischargings all will be stacked, store with enclosing low bank between fields again after the remote conveying of pipeline.Stacking, storage and the pipe-line transportation substantial contribution that all will account for, severe contamination environment simultaneously, threatens the existence of " solvay soda process " soda ash manufacturer.Therefore, the direct processing of discharging alkaline residue is more and more paid attention to by people.

CN95106293.x application for a patent for invention disclosed " method of producing engineering soil from alkaline slag " is newly to discharge the alkaline residue waste liquid through the short period of time post precipitation, liquid portion is overflowed, and another part slag liquid is through press filtration.Alkaline residue after this press filtration enters agitating procedure again.And in stirring material process, add various add materials as: flyash, liquid slag, slag, lime, cement, terra alba, loess etc. are made engineering earth, and its filtering equipment adopts conventional plate-and-frame filter press, drum type vacuum filter etc.

Though aforesaid method is feasible, industrialization rate is low.

In addition, in the reinforcing process of engineering bound pair soft clay ground,, improve its bearing capacity, successfully used " vacuum is given and pressed the solid based method of soft base " for reducing the water ratio of foundation soil.

" vacuum is given pressure " mainly is: the object being treated surface is sealed with earth or plastic cloth, and lay filter water shoot, plate in object being treated, to connect vacuum pump, with the moisture sucking-off in the object being treated.

The objective of the invention is: a kind of method of discharging alkaline dregs to make engineering soil is provided, has problems thereby solved in the existing processing producing engineering soil from alkaline slag method.

Basic fundamental solution of the present invention is: ammonia alkali factory is produced the waste soda residue liquid that discharges in the soda ash process directly enter in the precipitation ground, and Xiang Chizhong adds precipitation agent and one or more additives and precipitates the technology that---stirring---extracts supernatant liquor, redeposition---stir and extract clear liquid.Above-mentioned technology can carry out making mixture more than the secondary repeatedly, then the said mixture material is dewatered, and the secondary that adds one or more behind the eliminating waste liquid once more adds materials, and mixes, and promptly can be made into engineering finished product soil.

Below the present invention is specified:

The direct dispatch of waste soda residue liquid of " solvay soda process " production soda factory discharging is to settling tank, with every 10m ³Containing 300kg left and right sides solid slag in the waste residue liquid is benchmark, Xiang Chizhong throws in the precipitation agent of 0.01～0.05kg, to quicken the precipitation of above-mentioned waste residue, this precipitation agent can be vitriol or double sulphate as saltcake, vitriolate of tartar, alum, and in the pond, add simultaneously once adding materials of one or more, add-on can above-mentioned alkaline residue solids content be that the basis is adjusted, as: lime 0～25kg, terra alba 0～25kg, water glass 0～5kg, slag powders 0～50kg, cement 0～25kg, liquid slag 0～50kg, flyash or adding calcium fly ash 0～50kg.Wherein water glass can select Tianjin Caustic Soda Plant to produce, and the product modulus is 2.5～3.3.When need added one or more and once add materials, should will once add materials earlier added after evenly stirring again.

Because precipitation agent and the effect that once adds materials, make that the solid, liquid phase materials separates rapidly in the waste residue liquid, the waste soda residue and the precipitation that once adds materials, sedimentation time can for 1～2 hour and get rid of top slag liquid after, stir and expected 1～10 minute.There are a large amount of moisture content to separate out after the stirring again, stopped to stir the back redeposition 1～10 minute, get rid of supernatant liquor, restir, redeposition, discharge opeing.Such operation can be carried out more than the secondary repeatedly, the water ratio in the waste soda residue is dropped to about 250%, and make mixture.

The above-mentioned mixture of making is carried out dehydration procedure, press vacuum hydroextractor to carry out, the said mixture material is dropped to below 180% at the water ratio after the dehydration as adopting to give.

In the mixture after above-mentioned each operation handled be that the following secondary that benchmark adds one or more adds materials: flyash or adding calcium fly ash 0～80%, liquid slag 0～80%, sand 0～80%, loess 0～80%, return stone sand return 0～80%, slag 0～80%, cement 0～20%, lime 0～20%, gypsum 0～20%, water glass 0～10% with the mixture weight.

Wherein the quality index of water glass is identical with an above-mentioned additive, when one or more add materials when the selection interpolation, adds after the homogeneous that will add materials earlier stirs again.

Secondary is added materials when mixing with the said mixture material, spare matter and stir and make engineering soil finished product soil.Can adopt the Mixing Machine of existing paddle formula or spiral or other form during stirring.The finished product soil of making can be directly used in made ground, as the construction highway subgrade, and the bottom land backfill, Wharf Construction basis, greening base soil and other construction project can reach 12 tons/m with its intensity of soil ²More than.

Described once add materials and selection that secondary adds materials can be according to the purposes of made finished product soil different the selection.

The present invention provides a feasible technical solution for direct processing of waste liquid, waste residue of solvay soda process production soda factory discharging, thereby solved owing to low bank between fields is stacked the environmental pollution that waste soda residue causes, with a difficult problem of occupying a large amount of land resourcess, when realizing that industrialization is handled waste soda residue continuously, make engineering earth and replace loess, can save, develop a large amount of land resources, thereby realized the comprehensive regulation the waste soda residue contaminate environment.

The present invention includes but be not limited to following examples:

Embodiment:

Waste soda residue liquid with the discharging of solvay soda process production soda factory directly enters in the settling tank, at every 10m ³Waste soda residue liquid in contain the solid-state waste soda residue of 300kg, and as benchmark.

Add 0.01kg alum and once add materials in settling tank, flyash 10kg, cement 5kg precipitates after 1 hour, slag liquid in the eliminating, and carry out following technological process: stir 2 minutes-precipitate 5 minutes.And eliminating supernatant liquor.Above-mentioned technological process is constantly carried out 3 times repeatedly, promptly makes mixture.Its water ratio is 200%.

Press vacuum dewatering plant to dewater 30 minutes to give in the said mixture material, get rid of the moisture content of wherein deviating from, and solid is taken out, the water ratio in the mixture is 170% at this moment.

Adding secondary in mixture in such a way adds materials, cement: 5kg, lime 5kg, adding calcium fly ash 30kg, before the interpolation secondary adds materials, the even matter that above-mentioned secondary should be added materials is mixed, promptly can be made into finished product soil after the even matter of secondary additive and mixture mixed, be directly used in backfill ground, its intensity can reach 12 tons/m after the compacting ²

Claims

1. the method for a discharging alkaline dregs to make engineering soil is characterized in that:

1. discharge alkaline residue liquid and directly knock down in the settling tank, and Xiang Chizhong puts into precipitation agent, (press 10m as vitriol or double sulphate 0.01～0.05kg ³Discharging contains the solid-state alkaline residue weight of 300kg meter in the waste residue liquid) and as add materials next time one or more: flyash or adding calcium fly ash 0～50kg, liquid slag 0～50kg, slag powders 0～50kg, cement 0～25kg, lime 0～25kg, terra alba 0～25kg, water glass 0～5kg;

2. after finishing operation 1., precipitate after 1～2 hour, carry out following operation successively, evenly stirred 1～10 minute, precipitate 1～10 minute, slag liquid in the eliminating, this operation is made mixture after can carrying out more than 2 times or 2 times repeatedly.

3. the mixture dehydration that will 2. make, eliminating waste liquid.

4. the mixture after 3. handling and be as the criterion with mixture weight and add one or more that following secondary adds materials: flyash or adding calcium fly ash: 0～80%, liquid slag: 0～80%, sand: 0～80%, loess 0～80%, return stone sand return 0～80%, slag: 0～80%, cement 0～20%, lime 0～20%, gypsum 0～20%, water glass: 0～10%.

5. the secondary that adds in is 3. added materials and make finished product soil after mixing with the mixture of 3. making.

2. according to the described method of claim, once add materials, when 4. described secondary adds materials to more than one, should earlier the even matter of this material be mixed the back and throw in when 1. described.

3. method according to claim 1 is characterized in that 3. described dehydration can be adopted to give to press vacuum hydroextractor to carry out.