generic treatment technologies for healthcare waste jorge emmanuel international experts’ workshop...

GENERIC TREATMENT TECHNOLOGIES FOR HEALTHCARE WASTE

Jorge EmmanuelJorge EmmanuelInternational Experts’ WorkshopInternational Experts’ WorkshopUNEP-DTIE-IETCJuly 19-20, 2012Osaka, Japan

TYPES OF TREATMENT TECHNOLOGIES (BY DISINFECTION PROCESS)

Thermal

Temperature

Chemical

Concentration

Irradiative

Radiation dose

Biological

MICROBIAL INACTIVATION

STAATT criteria for healthcare waste

Minimum requirement: Level III Reduction of vegetative bacteria, fungi,

lipophilic/hydrophilic viruses, parasites, mycobacteria by 6 Log or greater

Reduction of heat resistant spores by 4 Log or greater

Microbiological indicators Geobacillus stearothermophilus or Bacillus atrophaeus

spores

Mycobacterium phlei or Mycobacterium bovis

GENERIC TECHNOLOGIES

Information in the Compendium for each Generic Technology

Process DescriptionDiagram or sketchTypes of Waste TreatedRange of CapacitiesPathogen DestructionEmissions and By-ProductsOperational Details Installation RequirementsMaintenance Requirements


ThermalAutoclavesHybrid autoclavesContinuous steam treatment

systemsBatch microwaveContinuous microwaveFrictional heatingDry heatIncineration and related technologies


Autoclaves based on design

JacketedRetort

VacuumNon-vacuum

VacuumAir

Filter

Pressure Gauge

Safety Valve

Release Valve

Jacket

Autoclave Chamber

Charging Door

SteamSteam Trap

Steam Trap

Drain

Thermocouple


AutoclavesRange of capacities:

20 liters to over 20,000 liters per cycle (1 to 2700 kg/hr)

Parameters: 121 to 135 ºC 104 to 212 kPa gauge Exposure time Number of cycles Depth of vacuum

Low maintenance (except for door gasket)Lowest cost


Autoclaves (based on operation)

Pressure pulse

Pressure gravity (steam flush)

Vacuum pulsing

Pressure vacuum

Pre-vacuum autoclaves

Gravity displacement


Autoclave without shredding

Autoclave with shredding


Hybrid Autoclaves

Incorporate internal shredding, fragmentation, and mixing into the autoclave

Common types:

Rotating autoclaves

Autoclaves with internal shredders

Autoclaves with internal mixing arms


Hybrid AutoclavesBetter steam penetration, shorter

exposure timeHigher maintenance requirements

than autoclavesHigher costs than autoclavesRange of capacities:

38 liters to 21,800 liters (18 to 21,800 kg/hr)

Types of waste treated:Same as autoclave but also including anatomical waste


Continuous Steam Treatment Systems


Continuous Steam Treatment Systems

Range of capacities:100 to over 1000 kg/hr

Types of waste treated:Same as autoclave but also including anatomical waste

Higher maintenance requirements than autoclaves and hybrid autoclaves

Higher costs than autoclaves and hybrid autoclave


Microwave Technology

Magnetrons used to generate microwave energy at 2450 MHz frequency

Two types

Batch

Continuous

Two types based on design

Low pressure, low temperature (95 -100 ºC)

High pressure, high temperature (121, 135 ºC)


Batch Microwave Unit

Range of capacities:

30 to 210 kg/hr

Types of waste treated:

Same as batch autoclaves but some systems cannot handle sealed glass bottles with liquids and sharp metals not in containers

Low maintenance

Higher cost than batch autoclaves

microwavegenerator

wastebin

controls


Continuous Microwave Unit

lid

hopper

shredderwastebin

automaticloader

microwavegenerators

holdingtankmicrowave section

outletauger

air treatment system used when the lid is opened


Continuous Microwave Unit


100 to 250 kg/hr


Same as hybrid autoclaves and continuous steam treatment system

Higher maintenance compared to batch autoclaves and batch microwaves; similar to continuous steam treatment

Higher cost than batch autoclaves and batch microwaves


Frictional Heating Systems

“New kid on the block”

Uses both saturated steam and dry superheated steam

Heat to generate steam comes from heaters and from frictional heat due to high speed rotors operating at 1000 to 2000 rpm (about 15-30 rps)

Result is a dry powder

GENERIC TECHNOLOGIESFrictional Heating Systems


10 to 500 kg/hr


Same as hybrid autoclaves and continuous steam or microwave treatment systems

Typical cycle

time

T ºC

100


Frictional Heating Systems

Vapor exhaust to air filters

Sterilization chamber with high

speed rotor blades

Electrical panel

Discharge bin

Lid


Dry Heat Systems

Mainly natural or forced convection (hot air) and conduction from electrical resistance heaters


0.2 to 10 kg/hr


Same as autoclaves

Intended for small facilities


Incineration


10 kg/hr to over 20 tonnes per day


In addition to infectious waste, properly designed incinerators can handle pathological, laboratory chemical and pharmaceutical wastes

Historically common types of incinerators:

Dual-chamber incinerators

Multiple-chamber incinerators

Rotary kilns


Dual-chamber incinerator

Primary Combustion Chamber

Secondary Combustion Chamber Air Pollution Control System

To Stack

Ram Feed

Ash SumpPrimary Burners

Secondary Burner


Multi-chamber excess air incinerator


Rotary kiln

Hopper

Rotary Kiln

Ram or Auger Feeder

Secondary Combustion Chamber

Ash Sump

Gas Scrubber

Venturi Quench

Dry Chemical

Baghouse Fabric Filter

ID Fan

Packed Tower-

Demister

Stack


Other types of incinerators

Fluidized bed incinerators (generally not used with medical waste)

Stepped hearth incinerators

Moving grate or reciprocating grate (stoker) incinerators

Vertical combustors

BAT REQUIREMENTS UNDER THE STOCKHOLM CONVENTION

Incinerator Design

An incinerator should consist of: Furnace or kiln (primary combustion

chamber) Afterburner chamber (secondary chamber) Flue gas cleaning system Wastewater treatment if wet flue gas

cleaning is used

BAT air emissions performance level: 0.1 ng I-TEQ/Nm3 at 11% oxygen

BAT wastewater performance level for effluents from treatment of gas treatment scrubbers:

0.1 ng I-TEQ/liter

To be achieved by a suitable combination of primary and secondary measures


Primary measures

Introduction of waste at 850ºC or higher; automation to avoid introducing waste below 850ºC

Avoidance of temperatures below 850ºC and no cold regions

Auxiliary burners Avoidance of starts and stops Control of oxygen input


Primary measures

Minimum residence time of 2 seconds at 1100ºC in the secondary chamber after last addition of air and 6% O2 by volume (for waste with >1% halogenated substances)

High turbulence of exhaust gases and reduction of excess air

On-line monitoring for combustion control and regulation from a central console.

Temperature, oxygen, carbon monoxide, dust


Secondary measures

Dedusting

Fabric filter operating below 260ºC

Ceramic filter used between 800 to 1000ºC

Cyclones for pre-cleaning

Electrostatic precipitators around 450ºC

High performance adsorption units with activated carbon


Secondary measures

Techniques for further emission reduction

Catalytic oxidation

Gas quenching

Catalyst-coated fabric filters

Different types of wet or dry adsorption systems using mixtures of activated charcoal, coke, lime and limestone solutions


Disposal of Residues (bottom and fly ash)

Ash should be handled, transported (using covered hauling) and disposed of in an environmentally friendly manner

Catalytic treatment or vitrification of fabric filter dusts

Disposal in safe dedicated landfills (e.g., landfilling in double-walled containers, solidification, or thermal post-treatment)


Monitoring

Routine monitoring of: CO, oxygen, particulate matter, HCl, SO2, NO2, HF, air flows, temperatures, pressure drops, and pH

Periodic or semi-continuous measurement of: polychlorinated dioxins and furans


General measures

Operation by trained, qualified personnel

Use of personal protection equipment

Periodic maintenance including cleaning of the combustion chamber and declogging of air flows and fuel burners

Auditing and reporting systems

Routine inspections of the furnace and air pollution control systems by the regulatory authorities


EXAMPLES OF OTHER ENVIRONMENTAL REQUIREMENTS

Pollutant Units US EPA emission limits EU emission limits

Small Medium Large Daily average

0.5-hour average

0.5-8 hour average

Particulates mg/m3 50 17 14 10 10, 30

CO mg/m3 18 1.6 9.8 50 100, 100

Dioxins/furans ng TEQ /m3 0.0099 0.011 0.027 0.1

HCl mg/m3 17 8.9 5.9 10 10, 60

SO2 mg/m3 2.8 2.8 16 50 50, 200

Mercury mg/m3 0.011 0.0027 0.00099 0.05

Lead mg/m3 0.24 0.014 0.00053All reference conditions: 273°K, 101.3kPa, 11% O2, dry; Small ≤ 200 lbs/hr, medium > 200 to 500 lbs/hr, and large > 500 lbs/hr.For half hour averages, at least 97% of concentrations must meet the first value and 100% must meet the second value.

RESOURCES Guidelines on best available techniques and

provisional guidance on best environmental practices, to be posted on the Stockholm Convention website

http://www.pops.int/

Reference document on the best available techniques for waste incineration: BAT reference document (BREF), European Commission, 2008; available in the European IPCC Bureau website eippcb.jrc.es/pages/FActivities.htm

o “Standards of Performance for New Stationary Sources and Emissions Guidelines for Existing Sources: Hospital/Medical/Infectious Waste Incinerators – Final rule amendments,” 40 CFR Part 60, US Environmental Protection Agency, 2011


ChemicalAlkaline hydrolysisChemical disinfectionOthers


Alkaline hydrolysis

Specifically designed for pathological waste (anatomical waste, organs, tissues, cadavers, contaminated animal carcasses)

Alkali + heat

Two types:

High pressure

Low pressure


15 to 4500 kg per cycle


Chemical disinfectant treatment

Examples of disinfectants used:

Sodium hypochlorite, chlorine dioxide, peracetic acid, lime slurry, quarternary ammonium salts, glutraldehyde


40 kg/hr to 700 kg/hr High Speed Hamermill

Pressurized Kill Tank

Sodium Hypochlorite Injection System

Auger System

LFB 12-5


Biological Treatment for organic wastes (this has been used for placenta and small tissues)

Composting

Vermiculture

Biodigestion


Others (emerging technologies)

Ozonation

Dry chemical (calcium oxide-based)

Promession for anatomical waste

GENERIC TECHNOLOGIES: COMPARISON OF ENVIRONMENTAL AND OCCUPATIONAL SAFETY

Technology

Environmental Concerns Occupational Safety Concerns

Air Water Solid Residue Notes

Autoclaves X XX X XX High pressure

Hybrid autoclaves X XX X XX High pressure

Continuous steam treatment systems X X X X

Batch microwave technologies X X X X

Continuous microwave technologies X X X X

Frictional heat treatment systems X X X X

Dry heat treatment systems X X X X

Incinerators XXX XX XXX XXX Air emissions, ash

Alkaline hydrolysis technologies X XXX X XX High pressure, alkali

Chemical treatment systems XX XX X XXX Chemical exposure

X – minimal concerns, XX - some concerns, XXX - significant concerns

GENERIC TECHNOLOGIES: COMPARISON OF SOCIAL/CULTURAL ASPECTS

√ - small potential, √√ - medium potential; X – minimal concerns, XX - some concerns, XXX - significant concerns

Technology Potential for Job Creation

Social Concerns Notes

Autoclaves √√ X

Hybrid autoclaves √√ X

Continuous steam treatment systems √√ X

Batch microwave technologies √ X

Continuous microwave technologies √√ X

Frictional heat treatment systems √√ X

Dry heat treatment systems √ X

Incinerators √√ X X X There may be community opposition to incinerators in neighborhoods.

Alkaline hydrolysis technologies √√ X X X It may not be culturally or religiously acceptable for treating body parts.

Chemical treatment systems √ X X The community may be concerned with chemical accidents and releases

GENERIC TECHNOLOGIES: COMPARISON OF INSTITUTIONAL/REGULATORY REQUIREMENTS

X – few basic requirements, X X - some requirements, X X X - many requirements; (1) maintenance and repair of moving parts; (2) maintenance and repair of parts exposed to high temperatures and thermal stresses (e.g., refractories), corrosive gases, fly ash and dust, as well as maintenance and

repair of moving parts especially in the flue gas cleaning system

TechnologyInstitutional Requirements Regulatory Requirements

Notes Notes

Autoclaves X X

Hybrid autoclaves X X (1) X

Continuous steam treatment systems X X (1) X

Batch microwave technologies X X

Continuous microwave technologies X X (1) X

Frictional heat treatment systems X X (1) X

Dry heat treatment systems X X

Incinerators X X X (2) X X XAir emission testing and hazardous ash

disposal

Alkaline hydrolysis technologies X X (1) X

Chemical treatment systems X X (1) X X Chemical storage, disposal and residues

GENERIC TECHNOLOGIES: COMPARISON OF CAPITAL COSTS

Autoclaves

Autoclaves with Shredders


Hybrid Autoclaves


Batch Microwave Units

Continuous Microwave Systems


Incinerators with Air Pollution Control


Low-Pressure Alkaline Digesters

High-Pressure Alkaline Digesters

GENERIC TECHNOLOGIES: COMPARISON OF OPERATING COSTS

Technology Range of Capacities(kg/hr)

Range of Operating Costs(USD/kg)

Autoclave 2 to 3600 0.14 to 0.33

Hybrid autoclave 18 to 2200 0.05 to 0.12

Continuous steam treatment 100 to 1800 about 0.15

Batch microwave unit 1.5 to 31 about 0.13

Continuous microwave unit 100 to 810 0.07 to 0.11

Frictional heating 10 to 1500 >0.13

Incinerator with air pollution control 5 to 3500 0.27 to 1.66

Alkaline hydrolysis 7 to 4500 kg per cycle 0.10 – 0.19

Chemical treatment 23 to 410 0.12 to 0.52

GENERIC TECHNOLOGIES: QUALITATIVE COMPARISONS

1 2 3 4 5 6 7 8 9 10

Wide range of capacities +++ ++ ++ + ++ + - ++ + ++

Wide range of waste treated + ++ ++ + ++ ++ - +++ - +

Efficacy of microbial inactivation ++ ++ + + + ++ + +++ +++ ++

Volume reduction + ++ ++ + ++ ++ ++ +++ +++ ++

Mass reduction - + + - - + + ++ +++ -

Minimum space needed for installation ++ + + +++ + + +++ - + +

Minimum installation requirements ++ + + +++ + + +++ - + +

Degree of automation + ++ ++ +++ ++ ++ +++ ++ ++ ++

1 – Autoclaves; 2 - Hybrid autoclaves; 3 - Continuous steam treatment systems; 4 - Batch microwave technologies; 5 - Continuous microwave technologies; 6 - Frictional heat treatment systems; 7 - Dry heat treatment systems, 8 – Incinerators; 9 - Alkaline hydrolysis technologies; 10 - Chemical treatment systems

GENERIC TECHNOLOGIES: QUALITATIVE COMPARISONS

1 – Autoclaves; 2 - Hybrid autoclaves; 3 - Continuous steam treatment systems; 4 - Batch microwave technologies; 5 - Continuous microwave technologies; 6 - Frictional heat treatment systems; 7 - Dry heat treatment systems, 8 – Incinerators; 9 - Alkaline hydrolysis technologies; 10 - Chemical treatment systems

1 2 3 4 5 6 7 8 9 10

Environment + + ++ ++ ++ ++ ++ -- - -

Occupational safety - - ++ ++ ++ ++ ++ -- - --

Job creation (based on equipment size) +++ +++ +++ + +++ ++ + +++ ++ ++

Social acceptance + + + + + + + -- - -

Institutional requirements +++ ++ ++ +++ ++ ++ +++ + ++ ++

Regulatory requirements +++ +++ +++ +++ +++ +++ +++ + +++ ++

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