Hazardous Waste Management

Hazardous Waste Management

Kitipan Kitbamroong Ph.D.7 January, 2011

Description

• Chemical fate and transport in

the environment. Frequency

and magnitude of accidents

involving hazardous materials.

Effects of these releases on the

community

Textbooks

• Hemond, H.F. and E.J. Fechner-Levy. Chemical Fate and

Transport in the Environment. 2nd edition. Academic

Press. ISBN: 0123402751. 448 pages. October 1999.

Instructor and Goals

• Instructor: Kitipan Kitbamroong Ph.D., email

kitipan@gmail.com

• Course Goals: Integrate chemical property information to

better understand the transport and fate of hazardous

chemicals released to the environment. Examine case

studies to understand the long-term social and

environmental effects of these releases.

Topics and Agenda

• 1.1 Introduction

• 1.2 Chemical Concentration

• 1.3 Mass Balance and Units

• 1.4 Physical Transport of Chemicals

• 1.5 Mass Balance in an Infinitely Small Control Volume

• 1.6 Basic Environmental Chemistry

• 1.7 Error in Measurements of Environmental Quantities

• 1.8 Chemical Distribution among phases

1.1 Introduction

• “By sensible definition any by-product of a chemical

operation for which there is no profitable use is a waste.

The most convenient, least expensive way of disposing of

said waste – up the chimney or down the river – is the

best.”

Haynes, W. American Chemical Industry, A History. Van

Nostrand, NY. 1954.

Processes

• 1.) wick effect: when water evaporates from soil surface, the suction gradient produced results

in an appreciable upward movement of water to replace that evaporated

• 2.) infiltration: (atmosphere soil) precipitation that doesn’t simply runoff the land surface into a

surface water body or storm drains enters the unsaturated zone (soil)

• 3.) evapotranspiration: evaporation from leaves (water from plant root uptake through the lip

of leave)

• 4.) dry deposition: any physical removal process that doesn’t involve precipitation, there are

three main mechanisms : gravitational settling (particle in the streamline settle down), impaction

(happen when hit building or something), absorption (particle absorp to surface of object)

• 5.) rainout: mechanism in wet deposition (removal process that involve precipitation), involve s

incorporation of chemical into water droplet that occur *within a cloud

Processes

• 6.) washout: wet deposition, occurs *beneath a cloud as precipitation fall through

the air toward the earth surface

• 7.) evaporation: process in which liquid transform to vapor, moving to atmosphere

• 8.) bubble bursting (sea spray): occur in few mm above ocean surface, there is a

lot of small water bubble (1-100 m dia) generate from dynamic action and come up

from ocean surface & broken in that top layer

• 9.) codistillation: evaporation & volatilization at the same time (simultaneous)

• 10.) excretion : the release of compound from organism to soil and water

Processes

• 11.) ingestion: uptake from soil and water to organism

• 12.) infiltration: (water-soil), movement of water from surface water body

to unsaturated zone, soil act as filter

• 13.) percolation: movement of water from unsaturated zone to sat

(groundwater)

• 14.) runoff: precipitation that runoff the land surface into a surface water

body

• 15.) leaching: dissolution of soluble compound from soil to water

1.2 Chemical Concentrations

• Mass per unit volume [M/L3], such as mg/L, is the most

common expression for water.

• ppm and ppb are often used.

• Mg/kg is often used for soils because the mass of soil does

not vary.

1.3 Mass Balances and Units

• Three possible outcomes exist for a chemical present at a

specific location in the environment at a particular time:

o The chemical can remain in that location

o Can be carried elsewhere by a transport process

o Eliminated through transformation into another chemical.

o The RULES of mass balance or mass conservation

1.3 Mass Balances and Units

• Mass Balance Equation

Change in storage of mass = mass transported in – mass transported

out + mass produced by sources – mass eliminated by sinks

• Mass Balance Rate Equation (mass per time)

Rate of change in storage of mass = mass transported rate in – mass

transport rate

• out + mass production rate by sources –

• mass elimination rate by sinks

1.4 Physical Transport of Chemicals

• Advection Transport

• Fickian Transport

1.5 Advection-Dispersion-Reaction Equation

1.6 Basic Environmental Chemistry

• 1.6.1 Chemical Kinetics

• 1.6.2 Gibbs Free Energy

1.6 Basic Environmental Chemistry

• 1.6.3 Chemical Equilibrium

• 1.6.4 Electroneutrality

• 1.6.5 Activity

1.6 Basic Environmental Chemistry

• 1.6.6 Chemical Kineticso First Order Kinetics – leads to exponential decay or first-order

decay

o Half Life - the amount of time it takes for the parent compound

to decay to half its initial concentration

1.7 Error in Measurements of Environmental Quantities

• The error of observation is the difference between the

measured value of a quantity and the accurate value.

1.8 Multiple phases present in the environment

• 1.8.1 Solubility and Vapor Pressureo Aqueous solubility is the concentration of a chemical dissolved in

water when that water is both in contact and at equilibrium with the

pure chemical.

• 1.8.2 Henry’s Law Constantso A partition coefficient describes how a chemical distributes itself

between two different phases.

o The Henry’s Law constant, H (or KH), is a partition coefficient defined

as the ratio of a chemical’s concentration in air to its concentration

in water at equilibrium

• 1.8.3 Chemical Partitioning to Solids

1.8 Multiple phases present in the environment

• 1.8.3 Chemical Partitioning to Solidso Sorption is the term used to describe the chemical partitioning

between air and solid phases.

o Adsorption is when the chemical sticks to the two-dimensional

surface of a solid.

o Absorption is when the chemical diffuses into a three-

dimensional solid.

1.8 Multiple phases present in the environment

• 1.8.3 Fugacityo Fugacity literally means the “tendency to flee” and is used to

determine to the relative concentrations of a chemical in air,

water, and soil phases at equilibrium (can also be used to

include other environmental phases, such as fish, bottom

sediments, dissolved gases, suspended sediment)

o Fugacity has units of pressure and is related to concentrations

through a fugacity capacity constant (in units of mol/atm-m3)

1.8.3 Fugacity

Level I

Level II

Level III and IV