C/ C) –1 *1000 C/ C) · 2020. 6. 30. · These DCR runs were made at a given reactor T (940, 970...

Operated by Los Alamos National Security, LLC for the U.S. Department of Energy’s NNSA

U N C L A S S I F I E D

(13C/12C)sample –1 *1000

(13C/12C)standard δ13C =

Slide 1



Pros: ASTM-D6866 standard method for detecting bio-C. Reliable. Cons: Establishing an AMS costs millions of dollars. Facility requires high maintenance and a dedicated team. Carbon-14 sample preparation is time consuming, e.g., prepare

graphite target, etc. Need do corrections, such as, “bomb C-14”, sample age effects

(perennial plants vs annual plants). Measurement precision is ±3%, based on ASTM-D6866. Cost of analyzing C-14 data is expensive.

Stable carbon vs radiocarbon isotope?

Pros: Much greater availability, easy operation, and relatively low cost of the instrument and per sample. Samples can be run in automated mode (~50 samples per day) and sample preparation is much simpler. Cons: Fatal: if the difference of the δ13C value between two end-members (VGO vs bio-oil is very small.

Slide 2



PRODUCT GAS C1-C4 H-C, H2 ~20 % of C

SYNCRUDE C5-C40 H-C (gas,diesel,bottoms) ~75 % of C

COKED CATALYST Flue gas (CO2) ~5 % of C

DCR VGO

BIO Davison Circulating

Riser

Stabilization Feed T / RX T (°F) % Bio-Oil co-processed DCR #

raw 107-127 / 970-1030 0, 1.5, 3, 5 1

mild 100-200 / 970-1000 0, 1.5, 3, 5, 10 3

medium 300-700 / 940-1000 0, 2.5, 5, 10 4

severe 300-700 / 970-1030 0,1.5, 3, 5, 10 2

VGO, bio-oil and co-processing products for carbon isotope analysis

Slide 3



2070

2075

2080

2085

2090

2095

2100

2105

-33 -31 -29 -27 -25 -23 -21

RUN

ID

δ13C (‰, vPDB)

DCR-3 (Pine, Mild) DCR-4 (Pine, Medium)

Carbon Isotope (δ13C) Compositions of Products

2185

2190

2195

2200

2205

2210

2215

2220

2225

-33 -28 -23δ13C (‰, vPDB)

RUN

ID

bio conc

5% bio norm

base

high temp 5% high temp base

low temp 5%

Bio ladder, norm

Slide 4



0

2

4

6

8

10

12

-32.0 -31.0 -30.0 -29.0 -28.0

Bio-

oil%

δ13C (‰, vPDB)

Mixture δ13C of Syncrude Product gas VGO Bio-oil -22.71‰

Flue gas

Mixing trends in DCR-3

Slide 5



y = 2.6592x + 81.782 R² = 0.78

y = 32.561x + 951.29 R² = 0.94

0

2

4

6

8

10

12

-32.0 -31.0 -30.0 -29.0 -28.0 -27.0

δ13C (‰, vPDB)

Bio

-oil

%

Syncrude

Mixture δ13C of Bio-oil & VGO

Product

Bio-oil -24.67‰ VGO

Mixing trends in DCR-4

Slide 6



0% bio

2.5% bio

5% bio

10% bio y = 2.6592x + 81.782 R² = 0.78

0

2

4

6

8

10

12

-32.0 -31.0 -30.0 -29.0 -28.0 -27.0

Bio-

oil %

δ13C (‰, vPDB)

Product gas δ13C

y = -19.356x - 596.79 R² = 0.90

-1

1

3

5

7

9

11

-32.0 -31.5 -31.0 -30.5 -30.0

δ13C (‰, vPDB)

Bio-

oil %

DCR-3 (Pine, Mild stabilization) DCR-4 (Pine, Medium stabilization) (bio conc ladder, normal)

Slide 7



Run ID δ13C STDEV Bio Oil (wt%)

Rx Temp

Feed Temp

Preheat Temp Notes:

2188 -29.185 0.011 0 970 213 250 bio conc ladder 2189 -29.172 0.002 1.5 970 211 250 bio conc ladder 2190 -29.105 0.047 3 970 205 250 bio conc ladder 2191 -29.122 0.045 5 970 201 250 bio conc ladder 2192 -29.208 0.009 0 970 206 250 bio conc ladder 2193 -28.908 0.054 10 970 186 250 bio conc ladder 2194 -29.227 0.030 0 970 214 250 bio conc ladder 2195 -29.050 0.001 5 970 207 250 bio conc ladder 2196 -28.927 0.033 5 970 300 382 5% bio normal yield curve 2197 -29.092 0.009 5 970 450 532 5% bio normal yield curve 2198 -29.174 0.017 5 970 575 704 5% bio normal yield curve 2199 -29.153 0.074 5 970 700 882 5% bio normal yield curve 2200 -29.283 0.042 0 970 701 855 base yield curve 2201 -29.300 0.023 0 970 576 685 base yield curve 2202 -29.194 0.016 0 970 452 521 base yield curve 2203 -29.268 0.001 0 970 300 375 base yield curve 2204 -28.974 0.074 5 1000 300 390 high temp 5% bio yield curve 2205 -29.079 0.008 5 1000 450 544 high temp 5% bio yield curve 2206 -29.119 0.036 5 1000 700 897 high temp 5% bio yield curve 2207 -29.059 0.059 5 1000 575 716 high temp 5% bio yield curve 2208 -29.206 0.045 0 1000 702 884 high temp base yield curve 2209 -29.194 0.071 0 1000 577 703 high temp base yield curve 2210 -29.188 0.018 0 1000 450 525 high temp base yield curve 2211 -29.190 0.009 0 1000 300 373 high temp base yield curve 2212 -29.284 0.048 5 940 700 881 low temp 5% bio yield curve 2213 -29.245 0.011 5 940 575 707 low temp 5% bio yield curve 2214 -29.211 0.013 5 940 450 531 low temp 5% bio yield curve 2215 -29.192 0.047 5 940 300 382 low temp 5% bio yield curve 2217 -29.148 0.044 2.5 970 300 381 bio conc ladder, normal 2218 -29.103 0.035 5 970 300 390 bio conc ladder, normal 2219 -29.002 0.025 10 970 300 413 bio conc ladder, normal

Average 0.031 Stdev 0.022

DCR-4 Syncrude δ13C

Slide 8



base yield

low temp 5% bio yield

high temp base yield

5% bio normal yield

high temp 5% bio yield

-29.30

-29.25

-29.20

-29.15

-29.10

-29.05

-29.00

-28.95

1 2 3 4 5

δ13 C

(‰ ,v

PDB)

Sample number

-29.261

-29.233

-29.194

-29.153

-29.058

DCR-4 Syncrude δ13C sample groups

Slide 9



Evaluating Significance of Isotopic Differences When End-members are similar in composition

When VGO and bio-oil end-members are close in isotopic composition, it can be challenging to discern trends. Pairs (I-J) of syncrude with statistically significant δ13C values are shown in blue.

Slide 10



Statistically different between the following groups : 1) “5% bio normal ~ base” (p=0.011, <0.05)

2) “5% bio normal ~ low temp 5% bio” (p=0.036, <0.05) 3) “base ~ high temp 5% bio” (p=0.003, <0.05) 4) “high temp 5% bio ~ low temp 5% bio” (p=0.010, <0.05)

Post Hoc Tests: Multiple Comparisons (DCR-4 Syncrude)

Slide 11



y = 32.561x + 951.29 R² = 0.9357

0

2

4

6

8

10

12

-29.3 -29.2 -29.1 -29.0 -28.9 -28.8

Syncrude δ13C (bio conc ladder)

Bio-

oil %

δ13C (‰, vPDB)

2.5% bio-oil

5% bio-oil

10% bio-oil y = 50.914x + 1486.6

R² = 0.9994

0

2

4

6

8

10

12

-29.20 -29.15 -29.10 -29.05 -29.00 -28.95

Bio-

oil

(%)

δ13C (‰, vPDB)

Syncrude δ13C (bio conc Ladder, normal)

DCR-4 Syncrude δ13C concentration ladders, T fixed

Slide 12



Feed T dependence of Bio-oil inclusion in syncrude

y = -2510.9x - 72454 R² = 0.80

0

200

400

600

800

-29.15 -29.10 -29.05 -29.00 -28.95δ13C (‰, vPDB)

Feed

T. (

F)

High temp 5% bio

y = -1372x - 39400 R² = 0.80

0

200

400

600

800

-29.20 -29.10 -29.00 -28.90

Feed

T. (

F)

δ13C (‰, vPDB)

5% bio normal

0

200

400

600

800

1000

-29.35 -29.30 -29.25 -29.20 -29.15δ13C (‰, vPDB)

Feed

T. (

F)

High temp base

Base yield

y = -4156.6x - 121001 R² = 0.97

100

300

500

700

900

-29.30 -29.25 -29.20 -29.15

Low temp 5% bio

δ13C (‰, vPDB)

Feed

T. (

F)

Slide 13



Stable Isotope Variations with Changes in Reactor and Feed T

These DCR runs were made at a given reactor T (940, 970 or 1000F) and variable feed T (~300, 450, 575 and 700F) to test how T affects co-processing.

Stable isotope compositions are consistent with decreased incorporation of renewable C into syncrude as feed T increases.

Changes in renewable C incorporation are much more sensitive to reactor T. A similar degree of incorporation is seen at 970 and 1000F, but less is seen at 940F.

By comparison, VGO-only processing is affected in a minor way by reactor T, but not by feed T.

Slide 14



Syncrude δ13C in 4 DCR campaigns

-29.3

-29.2

-29.1

-29.0

-28.9

-28.8

-28.7

-28.6

-28.5DCR-2 DCR-3 DCR-4 DCR-1

δ13 C

(‰, v

PDB

)

14.9 PMC

7.6 PMC 5.2 PMC

2.1 PMC 5% bio-oil

Slide 15



The pMC in co-processing products correlate well to the amount of bio-oil in the feed mixture (2.5 – 10wt%), and reflect the relative apportionment of the renewable carbon to these products (more renewable C to corn stover syncrude than pine syncrude; more renewable C to syncrude relative to product gas).

14C results for DCR-4 concentration ladders

Slide 16



0

2

4

6

8

10

12

0 2 4 6 8 10 12Bio-oil %

14C

% P

MC

2.5% bio-oil

5.0% bio-oil

10.0% bio-oil

∆14C=5.4 PMC

∆14C=3.2 PMC

14C results show more bio-C inclusion in syncrude than that in product gas for DCR-4

Slide 17



Carbon Isotope (δ13C) Compositions of Syncrude From Concentration Ladder Experiments

Rx T=970F, Feed T=186-214F, Preheat T=250F Rx T=970F, Feed T=300F, Preheat T =381-413F Rx T=970F, Feed T=201-213F, Preheat T=250F

Feed T=700F

Feed T=575F

Feed T=450F

Feed T=700F

Feed T=575F

Slide 18



Correlation between 14C and δ13C

Slide 19



Summary

14C is a powerful tool for detecting biogenic carbon for co-processing study, but it has some disadvantages, such as too expensive, not easily available, in particular, the “Bomb Carbon” effect, sample contamination.

Stable carbon isotope can be alternative for co-processing study, and is a reliable tool if the bio-oil is prepared from C4 plants, such as corn stover, switchgrass, sorghum, miscanthus, sugarcane.

C3 plant bio-oils are fine as long as the δ13C difference between VGO and bio-oil is big enough. The high precision IRMS can still detect meaningful signal. But if the difference is very small, the stable isotope application is limited.

our study demonstrates the utility of stable isotopes to: • capture a record of renewable carbon allocation between FCC products of co-processing • record changes in carbon apportionments due to changes in reactor or feed temperature

The correlation between measured 14C and δ13C may be useful as an alternative to carbon accounting, but the relationship must first be established for different bio-oil sources.

Slide 20

C/ C) –1 *1000 C/ C) · 2020. 6. 30. · These DCR runs were made at a given reactor T (940, 970...

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Transcript of C/ C) –1 *1000 C/ C) · 2020. 6. 30. · These DCR runs were made at a given reactor T (940, 970...