Supercritical Water 

Oxidation TOC AnalysKeith McLeroyAssociate Training SpecialistTEEX-Water & Environmental Water & Environmental

Training Program

C ll St ti TX College Station, TX.
TOC Analyses

• When measuring Total Organic When measuring Total Organic

Carbon (TOC), several techniqu

are used to oxidize the organic are used to oxidize the organic

carbon in the sample to form ca

dioxide.

• Once the CO

2 is formed it can b

d t t d d tifi d d

e

tec

t

e

d an

d quantifi

e

d.
TOC Con t’ .

• The main problem facing TOC analy

ensuring efficient oxidation of the orcarbon.

• The GE InnovOx TOC Analyzer use

Standard Methods wet chemical oxi

technique (5310 technique. (5310-D ).

• The InnovOx is currently being utiliz

TEEX Global Petroleum Research TEEX, Global Petroleum Research

Institute in a wide variety of researcapp p j lications projects.
Super Wet-Critical 

Oxidation Method• Supercritical Water Oxidation (SCW

Supercritical Water Oxidation (SCW

was originally developed to treat larvolumes of a

q 

ueous waste streams

sludges and highly concentrated brine/mineralized waters

• SCWO destroys organic wastes usi

oxidant in water and temperatures a

pressures ab th iti l i t f bove the critical poin

t o

f

water, 375 °C, and 3,200 psi.
SWCO Description

• The InnovOx employs a 30% employs

a 30%

weight/volume solution of sodiu

persulphate as the oxidizer It th

as the oxidizer. It th

heats the sample and oxidizer i

seal d t t th iti l 

le

d reac

tor pas

t the critical p

and Supercritical Water Oxidati

(SCWO) is achieved.
Why SWCO ?

• Research performed in the 1970’s fo

the SCWO technique to have many characteristics that were ideal for an analytical technique relying on efficianalytical technique relying on effici

sample oxidation and accounting fo

difficult sample matrices difficult sample matrices.

• Numerous studies have demonstrat

that the process achieves oxidation that the process achieves oxidation

efficiencies of > 99% for residence tof 10 to 30 seconds.
SWCO Chemistry

• When water reaches a supercri

When water reaches

a supercri

state, organic material and gase

become highly soluble while become highly soluble, while

inorganic salts become insolubl

• S lt ill t i ll th S

alts will

typically scavenge the 

oxidizer, resulting in an incomp

organi b t b di id ic car

bon 

to car

bon dioxid

conversion.
SWCO Chemistry Con

SWCO Chemistry Con• The InnovOx takes the takes the

environmental sample to a 

supercritical state by increasing supercritical state by increasing 

temperature and subsequently 

pressure within the reactor pressure within the reactor.

• The InnovOx uses a titanium 

oxid ti h b bl f id

ation c

ham

ber capable o

f

withstanding excessive pressur
SWCO Is In Short: SWCO Is

...In Short:

• The properties of supercritical w

The properties of supercritical w

enable the ultra-efficient, rapid 

oxidation of organic carbon to Coxidation of organic carbon to C

even in the presence of chloride 

other inorganic species that other inorganic species that

negatively interfere with non-SC

wet chemical oxidation wet chemical oxidation.
Meaning

• Environmental samples of vario

Environmental samples of vario

matrices can be analyzed witho

interferences.

• This application is an important 

prot l f th iti l l 

tocol for the critical analyses 

broad range of very difficult sam

• i.e.: oil-field wastewaters, frac-f

back and brine waste ponds.
TOC Detection in 

Environmental Matric• When testing for TOC in the detectio

When testing for TOC in the detectio

range of 0.5 to 50,000 ppm, it is vercommon to have a com

p 

licated sam

matrix. 

• S

p y ecificall

y, in a UV- Nondis

persive

infrared (NDIR) type system, the aggressive sample matrix attacks thl d d ti ll d it lamp an

d

dramatically re

duces its 

sensitivity to detection of TOC.
Detector

• The InnovOx uses a highly stab

uses a highly stab

nondispersive infrared (NDIR) 

detector. 

• Unlike other NDIR detectors the 

I O nnov x NDIR h i 

NDIR has no moving p

and features tight temperature 

cont l f th IR d trol of the IR source and

detector.
Environmental 

Applications• Flow

-back waters in well back waters in well fracing fracing

• Brine retention ponds• Wastewaters from petro,chemic

production & gas condensate 

management sites.

• Groundwater monitorin

g
Current Research at 

TEEX & GPRI• Frac

-water analyses protocol water analyses protocol

developments

• Li l ti hi f k Linear relationships o

f

known 

“difficult” to analyze sample ma

agai tk t d d ins

t

known s

tan

dar

d

s

• Oil/gas produced wastewaters 

clean-up technology, organic monitoring
Samples Analyzed So 

Fa

r

• Evaluations of a wide range of o

Evaluations of

a wide range of o

field waters in diverse matrices 

sludges liquids and glycol sludges, liquids and glycol

dehydrator condensates.

• B i t t t d/ t t d 

B

rine wa

ters, 

trea

t

ed/un

trea

t

e

d 

back & groundwater

• From these studies, protocols a

methodologies can be designed 

these applications.
Questions??

Thank you! Thank you!Keith McLeroy979-458-0912keith.mcleroy@teexmail.tamu.eduTexas Engineering Extension SerThe Texas A&M University SysteThe Texas A&M University Syste