CN105935698A

CN105935698A - Novel pollution site Cu in-situ detoxification method

Info

Publication number: CN105935698A
Application number: CN201610370350.6A
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: 2016-09-14

Abstract

The invention provides a novel pollution site Cu in-situ detoxification method. Sludge, a carbon source and sulfate are prepared into chemical agents to be injected into Cu-containing soil in an in-situ manner; and then a special constructing and curing manner is adopted, and a fixation ecological bacterium agent is made to gradually permeate into the underground to fix Cu of the deep-layer polluted soil. By means of the method, the Cu-containing site large in pollution depth can be efficiently restored at low cost; and meanwhile, waste is treated through waste, and the sludge is treated.

Description

A kind of novel contaminated site Cu situ detoxification method

Technical field

The present invention provides a kind of method of novel process Cu contaminated soil; it is primarily directed to the soil that Cu pollution depth is higher; mud, carbon source and sulfate are configured to medicament and are injected into containing in Cu soil in situ; use special maintenance method subsequently; Cu can be fixed efficiently; the most cost-effective, belong 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.Process the method containing Cu soil at present the most defective.High-temperature melting method cost is high, and power consumption is big.Bioanalysis is long for reaction time, and easily causes the secondary pollution of adventive microbial inoculum.Solidification method effect is unstable, and soil is easily caused secondary pollution by firming agent.The patent No. 201510056406.6 describes a kind of curing containing heavy metal soil, but the method using substantial amounts of material, relatively costly, on the other hand solidification effect is unstable, the most easily there is carbonation in the calcium oxide as added so that alkaline-curing effect reduces.

Summary of the invention

For the deficiencies in the prior art, the present invention uses a kind of novel contaminated site Cu situ detoxification method, mud, carbon source and sulfate are configured to medicament and are injected into containing in Cu soil in situ, use special construction and maintenance method subsequently, make fixing ecological microbial agent gradually permeate the ground, deep layer polluted soil Cu is fixed.The place containing Cu that pollution depth is higher can be repaired by this method with low cost and efficiently, 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 are 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) being forced through the reparation medicament batch (-type) in step (1) containing in Cu soil, injection pressure is at 0.1-1 MPa, and average every day, every square metre of injection rate was at 0-500L, was continued until that reparation terminates, during can constantly extract subsoil water；

(3) during repairing, it is desirable to the annual average rainfall in place is at more than 200mm, not enough then use the mode of surface sprinkling water to supplement, and enables medicament continuous to lower floor's seepage flow.

This method injects additional special field construction and maintenance in situ by special ecological medicament, place is promoted to form the flora based on sulfate reducting bacteria on a large scale, first this flora can utilize carbon source effectively to fix Cu, make full use of sulfate simultaneously, it is translated into 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 does not results in ecological problem；

3.Cu and sulfate reducting bacteria metabolite sulfide form sulfuration Cu precipitation so that in soil, Cu is more stable, 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 are 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 is as 0.1:1, mixed solution reaction 1 day, it is thus achieved that Cu soil remediation medicament；

(2) being forced through the reparation medicament batch (-type) in step (1) containing in Cu soil, injection pressure is at 0.1-1 MPa, and average every day, every square metre of injection rate was at 0-500L, was continued until that reparation terminates；

(3) during repairing, it is desirable to the annual average rainfall in place is at more than 200mm, not enough then use the mode of surface sprinkling water to supplement, and enables medicament continuous to lower floor's seepage flow；After engineering construction 2 years, more than 20 meters soil Cu stripping quantities 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 are mixed according to a certain percentage, after making mixing, solution dewatered sludge content is 5-20%, solid content 5-25%, organic carbon content 5-25%, the mass ratio of sulfate (remembering with SO4)/organic carbon is as 0.5:1, mixed solution reaction 2 days, it is thus achieved that Cu soil remediation medicament；

(3) during repairing, it is desirable to the annual average rainfall in place is at more than 200mm, not enough then use the mode of surface sprinkling water to supplement, and enables medicament continuous to lower floor's seepage flow；After engineering construction 1 year, more than 40 meters soil Cu stripping quantities 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 the present invention being described in detail with reference to previous embodiment, for the person of ordinary skill of the art, still the technical scheme described in previous embodiment can be modified, or wherein portion of techniques feature is carried out equivalent；And these amendments or replacement, do not make the essence of appropriate technical solution depart from the spirit and scope of claimed technical solution of the invention.

Claims

1. a novel contaminated site Cu situ detoxification method, is characterized in that, comprise the steps of

(2) being forced through the reparation medicament batch (-type) in step (1) containing in Cu soil, injection pressure is at 0.1-1 MPa, average every day, every square metre of injection rate was at 0-500L, was continued until that reparation terminates；

A kind of novel contaminated site Cu situ detoxification method the most as claimed in claim 1, 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.

A kind of novel contaminated site Cu situ detoxification method the most as claimed in claim 1, it is characterized in that, described carbon source solution can be containing organic solution such as ethanol, saccharide, protein, starch, can also be for the solution containing the industry organic solid waste such as organic waste, changing food waste, can also be industrial and municipal organic wastewater, described sodium sulfate can be substituted by the material of other containing sulfate.

A kind of novel contaminated site Cu situ detoxification method the most as claimed in claim 1, is characterized in that, constantly extracts subsoil water when of injecting medicament, forms negative pressure, makes medicament easily flow into underground.

A kind of novel contaminated site Cu situ detoxification method the most as claimed in claim 1, it is characterized in that, during reparation, the reparation medicament injecting place can be substituted by carbon source and sulfate mixed liquor, and in mixed liquor, the mass ratio of sulfate (remembering with SO4)/organic carbon is for (0-1): 1.

A kind of novel contaminated site Cu situ detoxification method the most as claimed in claim 5, it is characterized in that, carbon source and sulfate mixed liquor can add the subsoil water of place extracting, are then injected in place, and it is (0-1) that mixed liquid meets the mass ratio of Cu/ organic carbon: 1, the mass ratio of sulfate (remembering with SO4)/organic carbon is for (0-1): 1。