Chapter 15 Environmental pollution control

15.1 The goal of environmental pollution control 15.2 The types of environmental pollution control 15.3 The comprehensive treatment measures of environmental pollution15.4 Case study

15.1 The goal of environmental pollution control

15.1.1 Environmental pollution and its characteristics Generally speaking,environmental pollutants is in lower concentration

and long duration

Environmental pollutants can be changed by the biological or chemical

effect in environment

15.1.2 The goal of environmental pollution control Prevent pollutants going to water, atmosphere and soil system

Restore the use function of natural ecosystem

15.2 The types of environmental pollution control

Concentration control and total amount control

Terminal control and process control

Decentralized control and centralized control

15.3 The comprehensive prevention and control measures of environmental pollution

15.3.1 Water environmental pollution control (1) The principle and countermeasures of water polluti

on comprehensive prevention and control (2) Basic methods of water pollution controlPhysical method, chemical method, physicochemical me

thod and biological treatment method (3) Wastewater reclamation

Figure 15 － 1 The classification method of sewage biological treatment

Biological treatment

Aerobic treatment

Anaerobic treatment

Under natural conditions

Water self purification

Under natural conditions

Under artificially conditions

Water self purification

Soil purification

Suspended growth

Adnate growth

Natural water and oxidation ponds

Wastewater irrigation

Activated sludge and its deformation

Biological filter, Rotating biological contactor,

Contact oxidation, Aerobic biological fluidized blanket High-temperature compost Anaerobic pond

Suspended growth

Adnate growth

Septic tank, Upflow anaerobic sludge blanket

Anaerobic digester

Anaerobic biological fluidized blanket

Figure 15 － 2 Basic process of activated sludge process

Backflow sludge Surplus sludge

water-exit water inflow

air

primary settling tank secondary sedimentation tank aeration tank

灌入污水

下土层

根 区

Figure 15 － 3 Land treatment system of waste water

(4) The treatment process of waste water

The main task of primary treatment is to remove s

uspended solids in sewage, adjust pH valve, reduce t

he task of subsequent treatment

The task of secondary treatment is to remove the

dissolved and colloidal organic pollutants significantl

y. It is maily used biological method.

The purpose of tertiary treatment is to further re

move the pollutants which are not removed in secon

dary treatment.

Figure 15 － 4 Typical technological process of Municipal wastewater treatment

wastewater

Primary treatment

Pri

mar

y sl

udge

treatment or use

Sur

plus

slu

dge

grille Sedimentation tank

Grit chamber

Biological aeration

pool or biological filter

Second sedimentation tank

Chemistry, adsorption, ion exchange,

disinfection, equipment

Secondary treatment outlet

(emissions, irrigation)

Primary treatment outlet

(emissions, irrigation)

tertiary treatment outlet

(emissions, reoccupy)

Sludge

digestion pool

Backflow sludge

Sludge

dewatering

secondary treatment tertiary treatment

（ 5 ） Wastewater utilization The renewed wastewater can be used in industrial water, agricultura

l irrigation, urban and groundwater recharge, water treatment.The

affect of recycling and reuse in the entire water cycle is showed in fig

ure 15-5

废水回收

地下水回注 地下水 地下水

水处理

地表水

废水 城市用水 工业用水

废水

工业回用 排入地表水

农业回用

地表水

灌溉

降水

大气中水蒸汽

Figure 15-5 The effect of water treatment, regeneration and reuse to water-cycling system

15.3.2 The control of atmospheric environmental pollutio

n （ 1 ） The comprehensive treatment measures of atmospheric pollution

（ 2 ） Basic method of atmospheric pollution treatme

nt   The treatment of particle pollutants

Treatment technology of gas polutants

Cleaning particulate pollutants is usually used by duster device .Divided as its main mechanism,there are mechanical duster, wet duster, filter duster and electrostatic duster.

Figure 15-6 Structure profile of cyclone precipitator and spray wet precipitator

Figure 15-7 Operation simplified graph of bag dust collector

The treatment of gas pollutant

Absorption method

Adsorption method

Catalytic conversion process

Combustion method

Condensation method

Biological method

15.3.3 Pollution control of solid waste

（ 1 ） The definition and classification of solid waste

（ 2 ） The treatment and disposal and utilization principle of solid waste

harmlessness reduction resource

（ 3 ） The treatment and resource method of solid waste

The treatment and recycling technology of solid waste is mainly

include crushing, sorting, thermochemical processing and

biological treatment.

（ 4 ） The final disposal technology of solid waste

The final disposal method of solid waste can be divided to land disposal and ocean disposal according to the sites of waster disposal. The land disposal is a method based on the land and the soil layer to dispose the solid, divided into stockpiling method, land farming method, landfill method, deep perfusion method etc. The ocean disposal is to put the solid waster into the ocean by the capacity of ocean environment and its self-purification capacity.

Figure 15-8 The structural graph of safe landfill

（ 5 ） The treatment and disposal methods of hazardous waste

The dangers of hazardous waste is mainly for inflammable, ex

plosive, toxic, corrosive, radioactive and biological cumulative

etc. The treatment and disposal methods of hazardous waste a

re as following

Solidification and wrapping

Incineration Safe land landfill

15.3.4 Pollution control of soil environment

Pollution prevention measures of soil environment main

ly including:

Strengthen the source control and management of

contaminated soil

Technical measure of soil pollution treatment

Physical improvementChemical improvementBiological improvement

15.3.5 Other physical pollution control

Noise pollution control

Reform the technology, technics and equipments, reduce noise radiation intensity Reasonable city planning

Strengthening noise management

The technology to noise control Sound absorption: to reduce the nosie by absorbing sound through sound absorption material or sound absorption structures

Sound insulation : impeding the noise transmitting to the space by sound insulation structure, or control the noise in a certain range.

Sound elimination: reduce propagation of the noise in air by silencers

Radioactive pollution control

The main measures of radioactive pollution control are

include:

Strengthen the treatment of radioactive waste liquor

Properly handling and disposal of radioactive solid w

astes

The treatment of radioactive waste gas

Figure 15-9 Basic process of radioactive pollution control

Solidwaste

volume reduction

packaging storage transportation

emissions

proces

sing

Waste gas and liquid

treatment process

Shielding isolation room

storage curing

purification

The control of electromagnetic radiation pollution

Reduce the leakage of electromagnetic wavesAdopt effective control measures.Improve urban planning to achieve region contral

The control of light pollutionStrengthen urban planning and management, rational arrangement of light source,reduce the source of light pollutionSafe methods should be taken, such as using movable barriers surrounding the operating area to prevent the non-operator from directly exposure in the harmful light sourceTake the necessary personal protection, such as wearing goggles and protective masks which is effective personal protective measures

The control of heat pollution

Improve thermal energy utilization ratio, reduce

waste heat emissions

Active develop and use clean energy

Comprehensive utilization of waste heat

Increase afforest area

15.4 Case study Shenzhen Xiaping Landfill (1) the process of landfill (2) the treatment process of landfill leachate (3) the treatment and usage of landfill gas (LFG) (4) the measure of hygiene management

Spraying cars will spray the pesticides regularly, to kill the fly, to prevent the spread of bacteria.The sprinkler will sprinkes water regaularly to prevent the dust flying in the air and there is car washing equipment, to prevent polluting the road by the car’s sludge ,control dust, and also prevent taking pathogens outside.There are fence around the field to prevent light waster blown outside causing contamination.

Figure 15-10 Technological process of waste leachate treatment

调节池

吹脱

厌氧

A/O 系统

混凝

城市污水处理厂

污泥 填埋场

污泥 填埋场

达标排放

后期达到城市二级污水处理厂指标后直接排入

收集井

汇流中转器

输气管

抽气机（或气泵）

气体净化设备

气体加压机

燃气轮机（或气体内燃机）

发电机

自动点燃放空

LFG

CO2

Figure 15-11 Treatment and utilization technology of landfill methane

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