Heavy Metals Pollution in China

Dr Prof Li Xiao-ming

Member of Steering group of European Innovation Partnership on

Water (EIP)

College of Environmental Science and Engineering

Hunan University, Email: xmli@hnu.edu.cn;

--Challenges and Countermeasures

May 22, 2014

Contents

1 Heavy metals pollution in China

2 Heavy metals pollution in Hunan Province

3 Supporting policies and countermeasures

4 Heavy metals-containing wastewater treatment

5 Prospects and suggestions

Features:

♦ Serious and worldwide problem

♦ Strong enrichment and toxicity

♦ Structure irreversible changes and non-functionalization

of protein

♦ Not easy for treatment and remediation

Main contaminants:

Cadmium (Cd) Mercury (Hg) Copper (Cu) Lead (Pb)

Chromium (Cr) Arsenic (As) Nickel (Ni) Zinc (Zn)

Heavy Metals Pollution

Cancer villages in China

A government study has reaffirmed the existence of

"cancer villages" in China

China has more than 247 "cancer villages" throughout

the mainland

Toxic chemicals have caused several environment

emergencies linking to water and air pollution in these

areas.

Drinking water crises hit many regions while cancer

villages and other severe cases of health and social

problems emerged in some other regions

Cancer village distribution in China

Cancer village distribution in China

This photo shows the distribution of over one hundred cancer villages identified

by social activist Deng Fei several years ago

Excessive blood lead

in Chenzhou, Hunan,

2010

Lead contamination

in Neijiang,Sichuang,

2010

Cadmium contamination

in Longjiang, Guangxi,

2012

Cadmium, Thalium

polluton in Hezhou,

Guangxi, 2013

Arsenic pollution

in Linyi, Shandong,

2009

Chromium

contamination

in Loudi,Hunan,

2009

Recent

five years

The main heavy metal pollution accidents in China

Heavy metals pollution accidents in China

2 Heavy metal pollution in Xiangjiang River, Hunan

It is well known that there are abundant reserves of non-

ferrous metals in Hunan Province (Nonferrous metal Village),

and most ores for mining, mineral processing, non-ferrous

smelting and precious metals are located in the Xiangjiang

Valley.

The pollution treatment in this area was emphasized in The

Chinese Government’s 12th Five-Year Plan for Xiangjiang

River Water Environmental Pollution Control.

Fig. 1 The geographical location of ten stations in Xiangjiang River.

Fig. 2 Spatial variation maps of the heavy metal distributions in the soils from the

midstream and downstream of the Xiangjiang Valley (2012)

As

Zn Pb Ni

Cu Cr Cd

Heavy metal pollution accidents in Hunan Province

2006.1 Cadmium Pollution in Zhuzhou

2006.9 Arsenic Pollution in Yueyang

2009.6 Chromium Pollution in Shuangfeng, Loudi

2009.7 Cadmium Pollution in Liuyang

2009.8 Lead Pollution in Wugang

2010.3 Lead Pollution in Jiahe, Chenzhou

2011.3 Arsenic Pollution in Yiyang

2014.3 Arsenic Pollution in Shimen, Changde

Cadmium Pollution in Liuyang, Hunan, 2009

Pb pollution in Wugang, Hunan, 2009

More than 1300

children suffered

from Ld poisoning

As Pollution in Shimen, Hunan, 2014. The As concentration

in the exceed the standard 1000 times. Nearly half of the

local village people suffered from As poisoning, 157 persons

die from As poisoning.

Countermeasures and

suggestions

Department of

management

authority

Early warning and

emergency

response system

Governance policy

and measures

3 Supporting policies and safeguard measures

3.1 Department of management of authority

Department Responsibility

Regulatory Content

The Relative Legal Basis

Authority Executive Agency

3.2 Early warning and emergency response system

Early

warning and

Emergency

response

system

Soft

method

Participants

Environmental

Protection

Bureau,

Water Authority,

Government,

etc

Suggestions

Take preventive measures to

reduce pollution before events

occurs

Emergency response

system

Early warning systems

Take measures to reduce or stop

pollution when events had occurred

Hard

method

Similarly, soils in food crop farmland are categorized to result in high exposure of pollutants to human since the intake via the soil-plant-human pathway exists

Similarly, soils in food crop farmland are categorized to result in high exposure of pollutants to human since the intake via the soil-plant-human pathway exists

Similarly, soils in food crop farmland are categorized to result in high exposure of pollutants to human since the intake via the soil-plant-human pathway exists

Similarly, soils in food crop farmland are categorized to result in high exposure of pollutants to human since the intake via the soil-plant-human pathway exists

Similarly, soils in food crop farmland are categorized to result in high exposure of pollutants to human since the intake via the soil-plant-human pathway exists

Similarly, soils in food crop farmland are categorized to result in high exposure of pollutants to human since the intake via the soil-plant-human pathway exists

Strengthen the monitoring and management of

polluters, control the industry “three wastes” emission

Eliminate the outdated capacity and be strict with

approval requirements

Promote enterprise integration and improve industrial

concentration

Develop the circular economy

Governance Policy

3.3 Governance policy and measures in Xiangjiang

Valley, Hunan

Similarly, soils in food crop farmland are categorized to result in high exposure of pollutants to human since the intake via the soil-plant-human pathway exists

Similarly, soils in food crop farmland are categorized to result in high exposure of pollutants to human since the intake via the soil-plant-human pathway exists

Similarly, soils in food crop farmland are categorized to result in high exposure of pollutants to human since the intake via the soil-plant-human pathway exists

Similarly, soils in food crop farmland are categorized to result in high exposure of pollutants to human since the intake via the soil-plant-human pathway exists

Similarly, soils in food crop farmland are categorized to result in high exposure of pollutants to human since the intake via the soil-plant-human pathway exists

Similarly, soils in food crop farmland are categorized to result in high exposure of pollutants to human since the intake via the soil-plant-human pathway exists

Ecological comprehensive governance of heavy metal

pollution in the key industrial and mining area

River regulation of the sediment with heavy metals

pollution

Economical management of soil which contaminated by

heavy metals

Governance Measures

3.3 Governance policy and measures in Xiangjiang

Valley, Hunan

3.4 Case Analysis

— — As Pollution in Shimen, Hunan

Time-to-event: Have been reported in March, 2014.

Causes: Realgar slags over discharged which were used for arsenic

refining in factory at upper reaches from 1956 to 1978 (The factory was

stopped refining arsenic till 1978, but plenty of slags were still piled up in

the open air).

Influences: The region more than 30 square kilometers around of the land

were serious polluted. The water was useless and changed into white and

red. Land with no harvest, crops were severely damaged and difficult to sell,

but the villagers still have to eat because no other food else. Nearly half of

people in the village were arsenic poisoning patients, cancer patients could

be found everywhere.

Treatment measures:

The project: Implementation plan for the prevention and control of heavy

metal pollution "12th Five-Year Plan “ in Shimen realgar mining area

• Started in October, 2012, divided into four period, for 5 years

• The 1st and 2nd period for source control: The safe disposal of

nearly 200,000 tons of slags used for Arsenic refining and the

surrounding contaminated soil (basic problems are expected to be

solved in this August)

• 3rd period: local river comprehensive improvement

• 4th period: the remediation of about 5.3 square kilometers

contaminated soil in core pollution area

3.4 Case Analysis

— — As Pollution in Shimen, Hunan

Establish and improve the pollution prevention management

system

Identify heavy metals pollution risk

Construct compensation mechanism for environmental

damage

Strengthen technical guidance and regulation, promote the

industry transformation

Establish emergency response mechanism of

environmental pollution

Suggestions for heavy metal pollution control

4 Heavy metals-containing wastewater treatment

Chemical Methods

Physicochemical Methods

Biological Methods

4 Heavy metals-containing wastewater treatment

Applied Range: high concentration of heavy metal

wastewater treatment

Advantage: relatively simple and inexpensive to operate

Disadvantage: not economical, produce large amount of

sludge to be treated with great difficulties

Type: Chemical Precipitation

Electrolysis

New type of heavy metal capture agent

4.1 Chemical Methods

Tpye Advantage Disadvantage

Chemical

Precipitation

simple and convenient,

low cost

secondary pollution,

Disposal of the difficulty

Electrolysis

high heavy metal

concentration wastewater

treatment

energy consumption,

high cost

New type of heavy

metal capture agent

good selectivity,

high efficiency,

good stability of sediment

high cost,

disposal of the difficulty

4 Heavy metals-containing wastewater treatment

Ion Exchange

Membrane Filtration

Chemical Adsorbent

Coagulation and Flocculation

Flotation

4.2 Physicochemical Methods

Applied Range: low concentration of heavy metal

wastewater treatment

Advantage: energy-efficient, little or no secondary pollution

Disadvantage: high cost and maintenance

Type:

Type Advantage Disadvantage

Ion Exchange

high selectivity,

removal both anions and

cations

needs regenerated by chemical

reagents,

expensive,

cannot be used at large scale

Membrane

Filtration

high efficiency high cost,

process complexity,

the limit of membrane fouling

and low permeate flux

Chemical

Adsorbent

high efficiency high dosage, high cost,

complicated disposal after

adsorption

Coagulation

and

Flocculation

good sludge settling and

dewatering

chemical consumption,

large sludge production

Flotation

high selectivity,

high efficiency,

high overflow rates, low

detention periods, low

operating cost

high initial capital cost,

high maintenance and operation

costs

4 Heavy metals-containing wastewater treatment

4.3 Biological Methods

Applied Range: heavy metal wastewater

Advantage: high efficiency, high sorption capacity, low cost, no

secondary pollution

Disadvantage: still in the theoretic and experimental phase, the

separation of biosorbents would be difficult after adsorption

Type: Biological Flocculation

Biosorption

Phytoremediation

4 Heavy metals-containing wastewater treatment

4.3 Biological Methods

Biological Flocculation:

• A method for heavy metal removal by utilizing

microorganisms or their metabolic product for

flocculation precipitation.

• Currently, the developed microorganisms with

flocculation involved in 17 species, such as bacteria,

mycete, actinomyces, yeast and algae, etc.

4 Heavy metals-containing wastewater treatment

4.3 Biological Methods

Biosorption:

• Heavy metal ion absorbed by microbial cells after a

series biochemical reactions (complexation,

chelation, Ion exchange, adsorption).

• The mainly bio-adsorbents: algae, bacteria, fungi,

yeast, ect.

4 Heavy metals-containing wastewater treatment

4.3 Biological Methods

Phytoremediation:

• Reduce heavy metal content in contaminated soil

and surface water by plants absorption, precipitation

and enrichment.

• Available plants: algae, herbaceous plants, woody

plants, etc.

• Hyperaccumulator: special plants that could

excessive absorption and accumulation heavy

metals.

Table 1. Some hyperaccumulator plants with respective metal species

4 Heavy metals-containing wastewater treatment

Fig. 3 Influence of soil amendments and plants in the remediation of metal

contaminated soils

Type Advantage Disadvantage

Biological

Flocculation

safety, convenient,

non-toxic,

good flocculation

effect

high cost,

difficult to save the living flocculant,

still in the exploring stage

Biosorption low cost,

rapid adsorption

not suitable for high concentration

system because of the toxicity of

heavy metal

Phytoremediation

good selectivity,

high efficiency,

good stability of

sediment

plenty of plants containing heavy

metals would be difficult to disposal

5 Prospects and Suggestions

• Bioremediation technology, reported to be an effective,

nonintrusive, inexpensive, aesthetically pleasing, and

socially acceptable technology remediate water resource.

• Different environmental protection agencies are

appreciating the role of environmental biotechnology, and

expect to obtain global interests.

• Due to the limited resources, the heavy metals extraction

in wastewater (contaminated soil/surface sediments) and

recycling should considered as a direction in the future.