This document provides an overview of hazardous waste management and the design of a hazardous waste treatment center (HWTC). It discusses key topics such as the definition and characteristics of hazardous waste, past disposal practices, waste generation rates by industry, and the objectives and technical design of an HWTC. The proposed HWTC would include several treatment facilities like a liquid waste treatment plant, land farming facility, hazardous and regular waste landfills, solidification and stabilization unit, and incinerator. It emphasizes the importance of proper design, flexibility, environmental monitoring, and a phased approach to attract private investment and handle waste treatment and disposal.

1. Hazardous Waste
Management:Overview
Waste Management

2. Definition of Hazardous Waste
A solid or liquid wastes which because of its
quantity, concentration or physical, chemical
or infectious characteristics, may:
1. Cause increase in mortality or severe
illness,
2. Pose a substantial potential hazard to
human health or environment, when
improperly treated, stored, transported or
disposed

3. Definition of Hazardous Waste

4. Characteristics of Hazardous Waste
Ignitability (flash point >60oC)
Corrosivity (pH <2 or >12.5)
Reactivity (unstable materials or
material that cause violent reaction
when in contact with another material)
Toxicity (Leachate Test)

5. Nature of Hazardous Waste Management
Hazardous Waste field is interdisciplinary
Requires professionals with diverse
background working together to solve the
complex issue of hazardous waste
management
Environmental Impact and Risk Assessment
Treatment, Storage and Disposal
Waste Minimization, Recycling and Reduction
Management and Cost

6. Past Disposal Practice
 Soil Spreading
 Pits/Ponds/Lagoons
 Sanitary Landfills
 Drum Storage Areas
 Underground Storage
Tanks
 Midnight Dumping
 Uncontrolled Incineration

7. Waste Generation Rates By Industry
Chemical Products
Electronics
Petroleum & Coal Products
Primary Metals
Transportation Equipment
All Other Industries

8. Typical Hazardous Waste Types
25%
70%
Inorganic Liquid
Organic Liquid
Sludge

9. Why the need for HWTC?
Protect public health and the environment
Reduce impact of hazardous waste on
surface water and ground water
Provide the means to enhance:
Waste minimization at various industrial
operations, and
Waste recycling

10. Objectives of HWTC
1. Avoid and minimize environmental
and health pollution risks associated
with the generation, storage,
collection, transport, handling,
recycling, and disposal of hazardous
wastes
2. Ensure the movement and disposal
practice of hazardous wastes is
always controlled and environmentally
safe, flexible, and economically
sustainable for local conditions

11. Technical Feasibility
 Can the wastes be
separated at source to
avoid co-mingling and
analyzed before shipping
to the facility?
 What characteristics are
the separated wastes
likely to have?
 What quantity of the
wastes should be
considered as
wastewater?

12. Market and Economic Feasibility
 Is there a local market for the products of
recycling?
 Is there an international market for the
products of recycling?
 What scale of disposal fees is to be expected
for each category of waste?
 What rate of return would a Private Sector
investor expect for providing and operating a
Hazardous Waste Recycling Facility?

13. Materials Disposed in HWTC
Liquid organic waste
Oily sludge and residue
from petroleum industry
Spent oil and catalysts
Contaminated soil
Liquid heavy metals
Acidic and basic solids
and liquids
Liquid ammonia and
urea
Off-Specification
products

14. Estimation of Hazardous Wastes
Quantities??
Hazardous Waste Inventory:
Estimate the total waste stream quantity
Deduct the portion of these wastes that are
being recycled or processed at the generator’s
own facilities
Deduct any co-mingled wastes that are
impossible to separate in a cost-effective
manner

15. Estimation of Hazardous Wastes
Quantities (cont.)
Deduct waste quantities being disposed
without permit
Prepare an integrated treatment system for
the remainder with add-on facilities for growth
and improvement in anticipation of reducing
any unauthorized disposal
Propose action as necessary for treatment
and disposal facilities for the co-mingled and
improperly disposed wastes

16. HWTC Design Approach
1. A flexible modular design will provide the
Project Authority with the opportunity to
attract private sector investments and
will minimize capital cost in the long-term
–
–
–
Focus initially on the major polluters
Provide HWTC to treat part of the waste
Initiate and monitor

17. HWTC Design Approach (cont.)
2.
Due to the nature of the hazardous
wastes and their potential to change
characteristics and properties over
time, the HWTC needs to be properly
designed and equipped with facilities
that are capable of safely meeting the
needs of handling and disposing the
hazardous waste

18. Description of the HWTC
Liquid Waste Treatment
Facility
Land Farming Facility
Class I Hazardous
Waste Landfill
Class II Regular Waste
Landfill
Solidification and
Stabilization Unit
Incinerator

20. Important Points
 The priorities of hazardous Waste
management in decreasing order of
importance:
 Minimization/Prevention
 Treatment/Remediation
 Disposal

21. Liquid Waste Treatment Facility
Separate tank farm
storage for acidic and
basic waste as well as
drum storage area
Neutralization reactors
Sludge storage reactor
Standby neutralization
reactors to be used
during maintenance

23. Activated Carbon Column

24. Liquid Phase Adsorption Treatment System

25. Industrial Wastewater Treatment

26. Chemical Oxidation
In general the objective of chemical oxidation
is to detoxify waste by adding an oxidizing
agent to chemically transform waste
components
Chemical oxidation is a well established
technology that is capable of destroying a
wide range of organic molecules, including
chlorinated VOCs, phenols and inorganics
such as cyanide

27. Process Description
Chemical Oxidation is based on the delivery
of oxidants to contaminated media in order to
either destroy the contaminants by
converting them to innocuous compounds
commonly found in nature
The oxidants applied are typically hydrogen
peroxide (H2O2), potassium permanganate
(KMnO2), ozone (O3)

28. Process Description

29. Land Farming Facility
Land farming is the
preferred technology for
the treatment of oily
sludge and hydrocarbon
contaminated soils,
which constitute the
main component of
hazardous organic
wastes to be treated at
the HWTC

30. Base Liner Detail
WASTE
FILTER SOIL
GEOMEMBRANE
SUBSOIL
GRAVEL W/
PERFORATED PIPE

31. Land Farming Facility (cont’d)
Compounds to be treated at the land
Farming Facility:
 Volatile Organic Compounds (VOCs):
benzene, ethylbenzene, toluene, xylenes;
 Semi-Volatile Organic Compounds
(SVOCs): phenols, creosol, naphthalene,
phennathrene, benzo(a)pyrene, flourrene,
anthracene, chrysene; and
 Heavy Metals: chromium, cyanides, lead
and nickel

33. Aerobic Biodegradation
HYDROCARBON
PRODUCT
ORGANIC
POLLUTANT + MICROORGANISMS + NUTRIENTS + OXYGEN
CARBON DIOXIDE + WATER + BIOMASS

34. Microorganisms
• Regarding the natural breakdown of
hydrocarbon products, bacteria are the
main microorganism in the
bioremediation process
• Bacteria act as decomposers and utilize
hydrocarbon product as a source of
energy

35. Nutrients
 Nutrients enhance the biodegradation
process by supplying essential
elements required for optimal microbial
growth and maintenance
 Nutrients can be supplied in the field
through the application of manure or
fertilizer
 C:N:P = (100-300):10:1

36. Requirements for Biodegradation
 Proper nutrient balance
 Temperature
15 – 30 oC
 Acceptable pH
5.5 - 8.5
 Moisture content of 60% - 80% of field
capacity
 Oxygen concentration
 Presence of toxic heavy metals

37. REMOVAL EFFICIENCY (%)
AVERAGE NAPTHALENE
Naphthalene Removal Efficiency
100
80
60
40
20
0
0
100
200
300
400
TIME (hours)
Non-Acclimatized
Acclimatized
Control

38. Bio-piles

39. Soil Composting

40. Hazardous Waste Landfill





Class I Landfill
should include:
Double liner
Leachate collection
Leachate detection
system
Surface water
control mechanism
Impermeable cover
system

42. Hazardous Waste Landfill

43. Hazardous Waste Landfill
Liner System

44. Regular Waste Landfill




Class II Landfill
should include:
Single liner
Leachate collection
Surface water
control mechanism
Impermeable cover
system

45. Regular Waste Landfill

46. Solidification and Stabilization
The solidification and
stabilization facility
(SSF) will be designed
to inactivate and
immobilize
contaminants prior to
landfilling

47. Solidification and Stabilization
The following waste will be
processed by SSF plant
prior to landfilling:
 Mercury contaminated solid
wastes;
 Solid miscellaneous
inorganic sulfur;
 Semi-solid hazardous
waste; and
 Sludge from Liquid
Hazardous Waste
Treatment

48. Solidification and Stabilization
S/S reduces the mobility of hazardous
substances and contaminants in the
environment through both physical and
chemical means
S/S seeks to trap or immobilize
contaminants within their host medium (i.e.
soil, sand and binding agent)
Leachability testing is usually performed to
measure the immobilization of contaminants
from the stabilized matrix

49. Solidification and Stabilization
• General binding and
sorbent materials:
Cement
 Pozzolans
 Lime
 Silicates
 Organically Modified
Clays


51. High Temperature Thermal
Desorption
HTTD is a technology in
which wastes are heated
to 320 to 560 oC
Produce final
contaminant
concentration level
below 5 mg/kg

52. Incinerator
Structure to house the
furnace
Tipping floor where the
Hazardous Waste is
disposed
Storage pit to store the
Hazardous Waste
delivered
Charging system
Furnace
Air pollution control
Ash handling system

53. HWTC Control Philosophy
Provide a Supervisory Control and Data
Acquisition (SCADA). The SCADA
system will provide two levels of control:
Level 1 control operates equipment
directly and bypasses all interlocks.
Level 2 is initiated directly by computer
programming. Level 2 controls,
operates equipment and processes
remotely.

54. Typical Control System

55. Environmental Monitoring
 Air
Quality
 Groundwater
Quality
 Surface Water
Quality
 Dust and Noise

56. Environmental Monitoring
 Selection
of the
parameters of
concern
 Sampling
methodology
 Quality
assurance
/quality control
plan

57. Project Approach
Task 1: Review of Existing Data
Task 2: Discussion with Project
Authority
Task 3: Development and Finalization of
HWTF Design
Task 4: Prepare Final Design Drawings
and Design Basis Memorandum

58. Project Approach (cont.)
Task 5: Design of Liquid Hazardous
Waste Treatment Facility
Task 6: Class I and II Landfills Design
Task 7: Land Framing Facility Design
Task 8: Solidification and Stabilization
Facility Design

59. Project Approach (cont.)
Task 9: HWTC Construction
Task 10: Facility Commissioning and
Operation
Task 11: Facility Handing Over

60. Conclusions
1. Key to proper design of HWTC is
system flexibility to adjust to
hazardous waste quantities and
properties over time
2. Enforcement of environmental law
and regulations

61. Leachate Treatment Using
Wetlands
Department of Environmental Engineering
Beijing University of Chemical Technology
December 2003

62. Wetlands
 Wetland is define as land having the water
table at, near or above the land surface or
which is saturated for long enough period to
promote wetland or aquatic processes as
indicated by hydric soils, hydrophilic
vegetation, and various kinds of biological
activity which are adapted to the wet
environment.

63. Treatment Mechanisms in a
Wetland System

64. Type of Engineered wetlands
Constructed wetland systems are classified
into
two general types:
 Horizontal Flow System (HFS)


Surface Flow (SF)
Sub-surface Flow (SSF)
 Vertical Flow System (VFS).

65. Horizontal Flow Wetland System

66. Surface Flow Wetland System

67. Subsurface Flow Wetland System

68. Field Monitoring

69. Field Monitoring
MW-4
Pump
Pond #2
Monitoring wells
MW-2
DC
BA
MW-1
MW-3
MW-5
Peat Filter
FSW-1 SW-1
SW-2
FSW-2
Pond #1
SW-4
Manhole
W-1
SW-3
FSW-3
W-2

70. Field Monitoring
18
16
14
12
10
8
6
4
2
97-6
97-5
97-4
97-3
97-2
97-1
96-8
96-7
96-6
96-5
96-3
96-2
0
96-1
Concentration (mg/L)
Boron Concentration
Monitoring Event
Pond
MW-A
MW-B
MW-C
MW-D
SW

71. Conclusions
 Boron adsorption was directly related to organic
content
 Peat filter was effective in treating landfill
leachate
 The adsorption capacity of the peat can be
significantly enhanced by lime addition