CN106040735A

CN106040735A - Heavily-polluted site Cu in-situ and ex-situ coupling detoxifying method

Info

Publication number: CN106040735A
Application number: CN201610370393.4A
Authority: CN
Inventors: 张大磊; 李瑞栋; 王欣玉
Original assignee: Qingdao University of Technology
Current assignee: Qingdao University of Technology
Priority date: 2016-05-30
Filing date: 2016-05-30
Publication date: 2016-10-26
Anticipated expiration: 2036-05-30
Also published as: CN106040735B

Abstract

The invention discloses a heavily-polluted site Cu in-situ and ex-situ coupling detoxifying method. Sludge, a carbon source and a ferrous sulfate are prepared into an agent to be applied into Cu-contained soil, then the special construction and maintenance modes are adopted, reducing ecological bacteria agents gradually permeate into the ground, and Cu of polluted soil in the deep layer is reduced. The method can repair the Cu-contained site high in pollution depth with low cost and high efficiency, use waste to treat waste and also process sludge.

Description

A kind of heavily contaminated place Cu is in situ and dystopy couples detoxification

Technical field

The present invention provides a kind of method of novel process Cu contaminated soil, and mud, carbon source and sulfate are configured to medicament It is applied to, containing in Cu soil, use special maintenance method subsequently, Cu can be fixed efficiently, avoid the two of sulfate simultaneously Secondary pollution, belongs to field of environment protection.

Background technology

Owing to mining, Metallurgical Waste Water arbitrarily discharge, cause a large amount of soil and polluted by Cu.Treatment of Copper soil at present Method the most defective.High-temperature melting method cost is high, and power consumption is big.Bioanalysis is long for reaction time, and easily causes adventive bacterium The secondary pollution of agent.Solidification method effect is unstable, and soil is easily caused secondary pollution by firming agent.The patent No. 201510056406.6 describe a kind of curing containing heavy metal soil, but the method use substantial amounts of material, cost Higher, on the other hand solidification effect is unstable, and the calcium oxide as added the most easily occurs carbonation so that alkali Property solidification effect reduce.

Summary of the invention

For the deficiencies in the prior art, the present invention uses a kind of heavily contaminated place Cu in situ and dystopy coupling detoxification, Mud, carbon source and ferrous sulfate are configured to pharmacy application in containing in Cu soil, use special construction and maintenance method subsequently, Make ecosystem revivification microbial inoculum gradually permeate the ground, deep layer polluted soil Cu is reduced.This method can be with low cost and efficiently to dirt The place containing Cu that the dye degree of depth is higher is repaired, and mud is processed by the treatment of wastes with processes of wastes against one another simultaneously.It comprises the steps of

(1) sodium sulfate, mud or carbon source solution being mixed according to a certain percentage, after making mixing, solution dewatered sludge content is 0.1- 20%, solid content 0.5-25%, organic carbon content 0.5-25%, the mass ratio of sulfate (remembering with SO4)/organic carbon is for (0-1): 1, Mixed solution reaction 0-5 days, it is thus achieved that Cu soil remediation medicament；

(2) top layer, Cu place 1-10m soil will be contained be excavated, lay the soil with mesh bottom the place after excavation subsequently Work film, excavation place surrounding is laid impervious material, is built up semiclosed stockyard；

(3) by the soil breaking in step (2) to below 10mm, it is laid on semiclosed stockyard, uses step (1) institute subsequently State medicament spray mixing, mixed proportion be the mass ratio containing Cu soil Yu medicament be 1:(0.1-0.8)；

(4) store up period, keep soil moisture content in 5-60% scope in 5-100 days in the early stage, make biochemical reaction be carried out, Amount reproduction sulfate reducting bacteria in the venue；Sprayed to place every 1-200 days the soil remediation medicine described in step (1) simultaneously Agent or carbon source solution, the accumulation organic carbon in spraying agent or carbon source solution and the whole place ratio containing Cu total amount is wanted for several times Ask and be not less than 0.5:1；Require the annual average rainfall in place at more than 200mm, the not enough then mode of employing surface sprinkling water Supplement, enable medicament constantly to lower floor's seepage flow.

This method is added by special ecological medicament and special place maintenance, promotes place to be formed on a large scale with sulphuric acid Salt reducing bacteria is main flora, and first this flora can utilize carbon source effectively to fix Cu, make full use of sulfate, by its turn simultaneously Turning to sulfide, Cu simultaneously, is converted into more stable sulfuration Cu precipitation by the most fixing Cu.

Comparing traditional containing Cu agent, soil treatment method, this method has a following advantage:

1. the sulfate reducting bacteria sulphate reducing in sludge microbial agent, generates sulfide, can be while more efficient fixing Cu；

2. the sulfate reduction flora cultivated itself is indigenous flora, and natural tolerance is strong, easily multiplies on a large scale in place, Can the most effectively fix Cu, and not result in ecological problem；

3. the Cu after reduction and sulfate reducting bacteria metabolite sulfide form sulfuration Cu precipitation so that in soil, Cu is more steady Fixed, it is significantly better than other biochemical process；

4. this method uses mud and debirs as primary raw material, greatly reduces cost；

5. this method uses in-situ immobilization to deep soil, it is to avoid the excavation of deep soil, greatly reduces cost.

It is embodied as example as follows:

Embodiment 1:

(1) sodium sulfate, mud or carbon source solution being mixed according to a certain percentage, after making mixing, solution dewatered sludge content is 0.1- 5%, solid content 0.5-5%, organic carbon content 0.5-5%, the mass ratio of sulfate (remembering with SO4)/organic carbon, as 0.7:1, mixes After solution reaction 2 days, it is thus achieved that Cu soil remediation medicament；

(2) top layer, Cu place 10m soil will be contained be excavated, lay the geotechnique with mesh bottom the place after excavation subsequently Film, excavation place surrounding is laid impervious material, is built up semiclosed stockyard；

(3) by the soil breaking in step (2) to below 5mm, mixing with step (1) described medicament subsequently, mixed proportion is for containing Cu soil is 1:0.5 with the mass ratio of medicament, and the semiclosed stockyard closing being subsequently placed to step (2) is stored up；

(4) store up period, keep soil moisture content in 5-60% scope in 20 days in the early stage, make biochemical reaction be carried out, Amount reproduction sulfate reducting bacteria in place；Initial 100 days every 2 days to the soil remediation medicine described in place sprinkling irrigation step (1) Agent or carbon source solution, the later stage is separated by natural law more than 20 days, for several times the accumulation organic carbon in spraying agent or carbon source solution with The whole place ratio containing Cu total amount requires to be not less than 0.5:1；By natural precipitation and artificial spray, make the average fall that place is annual The water yield is at 500mm.After engineering construction 2 years, more than 20 meters soil Cu content of deep layer are below 2mg/kg, and subsoil water amount containing Cu is less than 0.1mg/L。

Embodiment 2:

(1) sodium sulfate, mud or carbon source solution being mixed according to a certain percentage, after making mixing, solution dewatered sludge content is 5-15%, Solid content 5-15%, organic carbon content 5-15%, the mass ratio of sulfate (remembering with SO4)/organic carbon is as 0.5:1, mixed molten Liquid reacts 1 day, it is thus achieved that Cu soil remediation medicament；

(2) top layer, Cu place 5m soil will be contained be excavated, lay the geotechnique with mesh bottom the place after excavation subsequently Film, excavation place surrounding is laid impervious material, is built up semiclosed stockyard；

(4) store up period, keep soil moisture content in 5-60% scope in 20 days in the early stage, make biochemical reaction be carried out, Amount reproduction sulfate reducting bacteria in place；Initial 100 days every 2 days to the soil remediation medicine described in place sprinkling irrigation step (1) Agent or carbon source solution, the later stage is separated by natural law more than 20 days, for several times the accumulation organic carbon in spraying agent or carbon source solution with The whole place ratio containing Cu total amount requires to be not less than 0.5:1；By natural precipitation and artificial spray, make the average fall that place is annual The water yield is at 500mm.After engineering construction 1 year, more than 40 meters soil Cu content of deep layer are below 2mg/kg, and subsoil water amount containing Cu is less than 0.1mg/L。

Above example is only in order to illustrate technical scheme, rather than is limited；Although with reference to aforementioned reality Execute example the present invention has been described in detail, for the person of ordinary skill of the art, still can be to aforementioned enforcement Technical scheme described in example is modified, or wherein portion of techniques feature is carried out equivalent；And these are revised or replace Change, do not make the essence of appropriate technical solution depart from the spirit and scope of claimed technical solution of the invention.

Claims

1. heavily contaminated place Cu is in situ and dystopy couples a detoxification, it is characterized in that, comprises the steps of

(3) by the soil breaking in step (2) to below 10mm, it is laid on semiclosed stockyard, uses step (1) described subsequently Medicament spray mixing, mixed proportion be the mass ratio containing Cu soil Yu medicament be 1:(0.1-0.8), subsequently enter the phase of storing up；

(4) storing up period, in 5-100 days in the early stage, holding soil moisture content is in 5-60% scope, simultaneously every 1-200 days to field Soil remediation medicament described in ground implantation step (1) or carbon source solution, inject the accumulation in medicament or carbon source solution for several times Organic carbon and the whole place ratio containing Cu total amount requires to be not less than 0.5:1；Require the annual average rainfall in place 200mm with On, not enough then employing surface sprinkling water mode is supplemented, and enables medicament constantly to lower floor's seepage flow.

2. a kind of heavily contaminated place Cu as claimed in claim 1 is in situ and dystopy couples detoxification, it is characterized in that, described Mud is anaerobic sludge produced by sewage treatment anaerobic technique, it is possible to the double oxygen mud of admixture part.

3. a kind of heavily contaminated place Cu as claimed in claim 1 is in situ and dystopy couples detoxification, it is characterized in that, described Carbon source solution can be containing organic solution such as ethanol, saccharide, protein, starch, it is also possible to for containing industry organic waste, The solution of the organic solid wastes such as changing food waste, it is also possible to for industrial and municipal organic wastewater, described sodium sulfate can be by it The material of its containing sulfate substitutes.

4. a kind of heavily contaminated place Cu as claimed in claim 1 is in situ and dystopy couples detoxification, it is characterized in that, described Water in Water spray can be substituted by organic solution, and the organic carbon content of organic solution is 10-1000mg/L.

5. a kind of heavily contaminated place Cu as claimed in claim 1 is in situ and dystopy couples detoxification, it is characterized in that, step (2) described laying can be difficult for biological degradation material with the geomembrane material of mesh, it is possible to is biodegradation material；Mesh soil Aperture equivalent diameter in work film between 1-100mm, Kong Yukong at 0.01-10m.