Deep Waste Injection CSIR-RRL Bhopal May 21 Deep Injection for Waste Disposal and Biosolids Treatment Maurice B. Dusseault – U of Waterloo Satyendra Narayan

Deep Waste Injection

CSIR-RRLBhopalMay 21

Deep InjectionDeep Injectionfor Waste Disposal and for Waste Disposal and Biosolids Treatment Biosolids Treatment

Maurice B. Dusseault – U of WaterlooSatyendra Narayan – Sheridan

Institute



Presentation SummaryPresentation Summary

Deep Injection of Solid Wastes Municipal biosolids treatment

Developed countries Rapidly growing countries (China, India…)

Deep Biosolids Injection Environmental advantages Cost advantages Reduction of all types of risk

What are suitable geological conditions? Why DBI in developing countries? Closure



What is a Solid Waste?What is a Solid Waste?

Standard municipal waste Biosolids (animal, human, vegetable) Industrial residuals

Fly ash, desulphurization sludges… Oilfield solid wastes, pipe scale…

Wastes from mineral processing Uranium tailings, S-rich waste… Red muds and pond sludges…

Contaminated soil (e.g. high Pb, Cd…) Solid radioactive wastes



Industrial, Mineral WastesIndustrial, Mineral Wastes

Fly ash, silica fume (beneficial use?) Mineral processing residues and

waste Red muds from Al processing Iron ore tailings, lead-zinc tailings, Au…

Slimes from chemical leaching NORMS, even radwastes Chemical process wastes

Pharmaceutical and plastics wastes Oil industry wastes



Waste pits in Indonesia





Wastes or Resources?Wastes or Resources?

Some wastes have beneficial uses CH4 from biosolids Secondary mineral extraction

However, beneficial use may come at too high a cost, with additional environmental risks, at too small a scale, or too slowly

Then permanent treatment or disposal is necessary in many cases



Example: Fly AshExample: Fly Ash

Utilization options… Bricks, low-grade cement Road base improvement (soil additive) Other beneficial uses…

However, if volumes are too large, some disposal becomes necessary Permanent tailings ponds Refilling the coal mine Large dry stockpiles (landfills) Deep injection as a slurry



Permanent Disposal OptionsPermanent Disposal Options

permanentwarehousing

landfills,quarries

old or new mines

saltcaverns

ocean dumping

deep slurry

injection

Geological Disposal of Solid Wastes

not to scale



Different Waste LevelsDifferent Waste Levels

Non-toxic, inert (e.g. FGD sludges) No environmental risks (e.g.

groundwater) Land use issues and transportation costs

Non-toxic but leachable (e.g. fly ash) Groundwater impairment from leachates Land use issues (ponds, landfills…)

Hazardous wastes (e.g. Pb, As-rich) Long-term surface disposal unacceptable Chemical methods (extraction, reaction) Deep geological disposal



Environmental Risk and CostEnvironmental Risk and Cost

Landfills, surface storage of wastes are high-risk solutions for wastes (liability)

Long-distance transport = risks and $$ Most chemical or high-temperature

methods are very costly (>$100/tonne)

Many processes create other waste streams

Geological entombment can give high security, minimize risk, at low $



Deep Solids InjectionDeep Solids Injection

Wastes are available as a particulate mass or as an existing slurry

The wastes are slurried and screened to avoid particles >5 mm

High pressure pumps inject the slurry Continuous hydraulic fracturing at

depth take place The overburden weight permanently

entombs the wastes as a solid mass



Oilfield WastesOilfield Wastes

Heavy Oil Treatment Site in Alberta-Tank bottoms (oil + minerals + H2O)-Stable emulsions-Some fine-grained sand



Cleaning Sludge from TanksCleaning Sludge from Tanks



Tank Bottom SludgesTank Bottom Sludges

50% H2O30% oil20% minerals



30 m30 m33 Vacuum Truck Vacuum Truck



Oily Sand WastesOily Sand Wastes



Sand Stockpile for DisposalSand Stockpile for Disposal



Solid and Liquid Co-Disposal Solid and Liquid Co-Disposal

The solids must be slurried Waste aqueous streams can be used But, if hazardous liquids are

disposed, higher environmental security needed

Different streams can be combined… E.g.: radioactive waste combined with

50% fly ash and 40% shale chips This will permanently isolate the

radionuclides by setting and adsorption Biological and inert wastes as well



View of SFI SystemView of SFI System



Oilfield Wastes - IndonesiaOilfield Wastes - Indonesia



Solid Waste Injection SiteSolid Waste Injection Site



Costing of Deep InjectionCosting of Deep Injection

Site choice, investigation, design Capital costs for siting

Injection equipment Drilled, cased wells (3-4 wells, ~500 m)

Operational costs Largely labor and engineering (reports,

monitoring of process, analysis…) Additional savings

Co-disposal of ~3 m3 waste water/tonne Co-disposal of other noxious wastes…



Inert Waste Solid InjectionInert Waste Solid Injection

A permanent disposal method Suitable for all non-hazardous

wastes Wastes must be ground to -5 mm Large volumes for cost effectiveness Suitable geological conditions Slurry water available (waste water) Wells available or can be drilled For hazardous wastes, additional

precautions can easily be taken



Can Deep Injection be Used Can Deep Injection be Used for Biological Solids?for Biological Solids?



The Reality in Some Places…The Reality in Some Places…

Municipal and animal biosolids treatment Poor or no treatment = contamination of

streams, land, groundwater, air Affects health conditions (dysentery, etc.)

Conventional treatment methods High capital costs for facilities CO2 released into the atmosphere Sludge disposal problems Some risks remain (heavy metals in soils,

H2O contamination, biotoxin escape…)



Typical Current TechnologyTypical Current Technology



In Developed Countries…In Developed Countries…

Large infrastructure investments have been made Full sanitary sewage collection systems No mixing with storm waters No voidage to streams or lakes Centralized treatment of sewage Digested sludge is disposed by

controlled spreading on fields, derelict land…

Large biosolids volumes from feed lots and poultry farming…



Some USA areas with biosolids concerns…



Some Concerns…Some Concerns…

Municipal sludge (residues) has: High heavy metals content Biologically dangerous agents (e.g.

chlorinated hydrocarbon traces…) Viruses and prions that may not have

been rendered biologically inactive Also…

All C in sewage becomes CO2

Land usage must be carefully regulated Transport risks, and other risks…



Developing Countries…Developing Countries…

India, China, etc. are developing rapidly: they need safe biosolids treatment

New treatment facilities are a large expense for many communities Extremely rapid urban growth since 1960 A sewage collection network may not exist

and retro-fitting is prohibitively costly Land spreading is no longer a viable method

of disposal for large urban centres Centralized treatment facilities to achieve

economies of scale are costly



Developing Countries…Developing Countries…

Traditional approaches Collection of nightsoil and animal wastes,

spreading on local gardens and fields Surface runoff problems in monsoons E. Coli contamination (e.g. Walkerton,

ON, seven dead and 1200 infected in 2000)

Dysentery, other problems Open burning leads to smoke pollution Burning of manure leads to eye

problems, other health issues…



Recent DevelopmentsRecent Developments

Biosolids digestors… Mainly for animal, vegetable wastes Generates CH4, sludge is spread on

fields Local technology, not for large cities

Energy generation… Organic matter (e.g. cane wastes) are

burned for power generation All C is converted into CO2

Composting (generally expensive) Other new technologies…



Biosolids Management Biosolids Management NeedsNeeds

India: Large population, growing

Urbanization taking place very quickly

Development rate is growing (up to 10%)

Large water contamination and health problems

How does one handle the wastes?



Chinese UrbanizationChinese Urbanization

Coastal city urbanization is a serious issue

Rivers are contaminated

Flooding Cities are under

great pressure But, geology is

generally good for DBI!



Biosolids ManagementBiosolids Management

Must protect human health Must be environmentally “friendly” Must be done at reasonable cost Must be done beneficially (value

added when economically possible) Options for municipal wastes include

Current technology (ponds, spreading …)

Thermophilic digestion (bioengineering) Incineration, other thermal methods… Deep biosolids injection



Deep Biosolids Injection Deep Biosolids Injection (DBI)(DBI)

A slurry of biosolids and waste water is injected into deep porous formations

A totally new method for treating bio-solids permanently, and with no sludge

It offers many environmental and energy advantages at low risk

Cheaper than conventional treatment Geological conditions are key!

Right geology Right hydrogeological conditions



Deep Biosolids InjectionDeep Biosolids Injection

Inject biosolids into old O&G reservoirs

Metals, bacteria, viruses, are isolated

CO2 generation does not take place

Anaerobic decomposi-tion forms CH4

CH4 can be used Small footprint Solid C is

sequestered

Gas to Energy Biosolids InjectionFacility

Methane

BiosolidsInjection

MethaneProduction



DBI ProcedureDBI Procedure

Municipal, animal, other biosolids are pre-treated to remove pathogens if necessary

Biosolids + waste water = aqueous slurry This slurry is injected into a deep

sedimentary sandstone formation Biodegradation generates useful CH4

Some elemental carbon remains behind All toxic or noxious agents permanently

entombed, no liabilities, low risks



A DBI SystemA DBI System



DBI Environmental DBI Environmental Advantages Advantages

Permanent waste storage with no long-term risks because of deep disposal

Permanent protection of surface and shallow water resources

Greenhouse gas reduction Reduction of CO2 & CH4 liberated Permanent C sequestration in solid form

Energy recycling (CH4 is recovered) Co-disposal of waste water Small surface footprint



Advantages of DBIAdvantages of DBI

Temperature at depth speeds up the biodegradation reactions

Generated CO2 (15%) is preferentially dissolved into the brine, stays behind

CH4 separates and sits as a “bubble” on the surface of the brine

CH4 can be extracted & used beneficially

Based on known petroleum technology Many years of experience exist with

non-biological solid wastes



Further DBI DetailsFurther DBI Details

Carbohydrates have ~30% surplus C, left behind as sequestered carbon

Other materials can be co-disposed… Cane wastes, other organic wastes Shavings, sawdust, etc Wood pulp liquors, other waste liquids Any other ground up solid (plastic, etc.)

No sludge ponds, no digesters used… Sealed DBI unit, no odor, no spray



Animal Waste Beneficial UseAnimal Waste Beneficial Use

Animal waste should be used beneficially and economically wherever possible

But, in large-scale production… Nitrate and phosphate loading of soils Groundwater issues Risks to humans (transportation, etc.)

DBI is an option for areas where: Large volumes cannot be used beneficially DBI can be done on site or close by



Geological Conditions for Geological Conditions for SitesSites

Deep, well below potable water sources Horizontal strata, good lateral extent Stratum must be thick & porous Permeability must meet standards Thick ductile overlying shales are good At least one overlying permeable bed Formation water briny, horizontal flow No exploitable resources involved



Ideal DBI LithostratigraphyIdeal DBI Lithostratigraphy

surficial deposits

mudstone

silty shaleblanket sand ina thick shale

channel sands ina silty shalecontinuousblanket sandlimestone

limestone stringer

possible DBI well locations

300

0-10

,000

’

5-30 km

flat or gently inclined strata

not to scale



Why a High-k Site?Why a High-k Site?

They have high porosity, therefore they have good storativity

Flow usually horizontal in high k zones High site means high compressibility High k means that there are no large

pressured zones generated Pressure leak-off is very rapid, solid

wastes are localized near well Much better than injection into a

shale!



Current Phase of the Post-Glacial Fraser Delta (GSC Canada)

VANCOUVER AREA

10 km



Vancouver Groundwater Vancouver Groundwater FlowFlow

deep slurry

injection

not to scale

Recharge area, high precipitation

Vancouver urban area

Discharge subseaSediment wedge, ~1200 mHigh porosity

sandstone

West East

shales



Similar Conditions in IndiaSimilar Conditions in India

Many coastal cities sit on sedimentary wedges with subsea discharge

Chennai, Kolkata, Mangalore, Mumbai Calicut are some examples

In these cases, regional groundwater flow is down, out to the sea, with subsea discharge

The hydrogeological security in such cases is tremendous



Environmental Risk and CostEnvironmental Risk and Cost

Landfills, surface spreading are high-risk solutions for sludges (liability)

Long-distance hauling = risks and $$ Chemical, high-T, composting methods

are costly (>$80/dry tonne) Some processes actually create new

waste streams DBI can give high security, eliminate

liability, lower costs in many cases



Typical Costs, 600,000 Typical Costs, 600,000 peoplepeople

Capital Expenditures: Conventional treatment centre in India:

40 M$, maybe more, for a central facility DBI facility + dewatering and primary

treatment: ~10-15 M$ Operating Expenses:

Conventional treatment: 20-30$/ dry tonne of biosolids (New York is 125$/tonne)

DBI: 15-20$/dry tonne (Based on conventional treatments)



DBI Well CompletionDBI Well Completion

conventional high security

surface casing

perforated zone

injection casing

not to scale

impermeable,ductile shale

security casing

potable watersources

SFI stratum



Injection of Oily SandInjection of Oily Sand

HopperScreen

Mix Tank

Pump

Hydraulic unit

Fuel

Control trailer

Oversize

Los Angeles Area, 1998



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A Brief HistoryA Brief History

Massive sand injection technology developed in Canada in 1992-1997

Biosolids disposal & CH4 generation + C sequestration concept in 1997

Vancouver, Canada, studies DBI carefully, declines (2000)

City of Los Angeles, 1999-2004 All permits obtained by fall of 2003 Construction permit soon, 2005



Why Los Angeles??Why Los Angeles??

They have no space to spread sludge They lost a law suit in 2001 so they can

no longer use adjacent county land Their need is urgent The geological conditions are very good Many old oil fields, huge capacity United States Dept. of Energy and the

EPA are interested in energy recycling The costs are lower than current

ways…



Los Angeles Treatment SitesLos Angeles Treatment Sites

Hyperion

TerminalIsland OCSD

Plant

Carson JWPC

Old oil fields

DBI site, 2005

startup



Typical Injection ParametersTypical Injection Parameters

Slurry density 1.15-1.30 g/cm3

Injection rates 2-2.5 m3/min Injection period 6-10 hrs/well Operational hours 20 hours/day

(with 3 or 4 wells) Availability ~300 days/yr Slurry volumes ~2000 m3/day Yearly capacity >100,000 dry t Rating City of 500,000



Duri Slops InjectionDuri Slops InjectionCPI Duri SFI Well 64AJun 26 - Jun 30, 2003

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DBI in DBI in India?India?



Why in India?Why in India?

Rapid development of cities leads to: Need for safe biosolids disposal High land costs, redevelopment

expenses Restrictions on land spreading

Cities beginning to implement high quality sewage treatment

The costs with DBI would be lower The risks are also lower The benefits seem substantial…



Where in India? Where in India?

Where there are at least 500 m seds.

With suitable porous and permeable sands

Appropriate hydrogeological conditions

Suitable geographic and tectonic conditions

Etc…



Where in India…?Where in India…?

Cities such as Raipur, Delhi, Bhopal, Ahmadabad, Kolkota, all sit on thick sediments (Ganges plain, sedimentary basins…)

Coastal cities such as Mumbai, Chennai, Calicut, Bhubaneswar sit on suitable wedges of sediments

Offshore sediments are also OK However, DBI may not be practical

everywhere…



Except for areas where there are igneous rocks, or in the mountains, much of India seems suitable for DBI!



DBI AdvantagesDBI Advantages

Wastes permanently, deeply entombed Proper siting gives exceptionally high

environmental security (minimal risk) No chance of “repository” impairment or

surface H2O contamination Generated CH4 can be collected & used Less CO2 emitted & C is also sequestered Costs much less than current technology Very rapid to implement (6 months)



Additional Advantages…Additional Advantages…

Land use requirements are moderate, compared to conventional

A DBI site can be used to co-dispose other waste materials Usually cheaper than other treatments Solids stay at depth, leachates also Hazardous leachates are absorbed by

clays in the sediments Contaminated water can be used to

formulate the slurry



Geological Constraints?Geological Constraints?

Depending on volumes and waste nature, different geological conditions are OK

Highly fractured igneous or metamorphic rocks could accept smaller volumes

Non-hazardous wastes could be injected at much shallower depths (100-300 m)

For highly toxic wastes, one can add cement (fly ash!), shale chips, etc.

Surface water protection is the key!



Closing CommentsClosing Comments

For developing countries, DBI seems to be an ideal technology to rapidly improve sewage treatment, at lower cost, and lower risk

Developed countries have huge investments in treatment sites, therefore they have already “paid for” sewage treatment

The geology over much of India and China seems ideal, or close to it…



Acknowledgements…Acknowledgements…

Terralog Technologies Inc, Calgary and the City of Los Angeles

US – EPA for slowly going through the approval process

Dr R.N. Yadava and RRL - Bhopal Colleagues

Documents

Deep Waste Injection CSIR-RRL Bhopal May 21 Deep Injection for Waste Disposal and Biosolids Treatment Maurice B. Dusseault – U of Waterloo Satyendra Narayan