Comparison of product yields
15 10 25 30 35 20 40
Product
DCU, Ind-Coker AT , Improvement, wt% wt% Δwt%
Base c ase DCU Ind - Coker
FG including H 2 S
4.93 3.54 4.93 1.75
6.73 4.14 5.63 1.38
+1.80 +0.60 +0.70 -0.37 +2.03 +0.52 -0.10 -5.18
LPG
LN (C5-120°C) HN (120-140°C)
LCGO (140-370°C) 33.75 HCGO (370-540°C) 19.73
35.78 20.25
0 5
CFO (540°C+)
0.78
0.68
Coke
30.59
25.41
Table 3
Product
‘add-on’ section without requiring costly grassroots units. This also provides additional flexibility to the refiner to operate in either Ind-Coker AT mode or conventional coker mode. Thus, the technology can play a pivotal role in reducing emissions and could be a key component for future refinery configurations. Results and discussion The results of pilot-scale experiments indicate a decrease in coke yield for the Ind-Coker AT technology compared to the conventional DCU. Corresponding to the reduced coke yield, there is a benefit in the yield of light distillates in the Ind-Coker AT technology case. This lower coke yield is due to the removal of a fraction of hydrocarbon molecules by mild cracking in the first step and intermediate separation. These molecules are prevented from entering the second step of high-severity coking,
Figure 3 Commercial yield comparison
Implementation in future refinery configuration
The fuel-grade petcoke is subjected to burning inside boilers, resulting in the generation of CO₂ and SOx. The deployment of Ind-Coker AT technology in a modern refinery will aid in reducing the coke make from the refinery. Reduced coke make from this technology in turn results in lower availability of high-sulphur petcoke for combustion in boilers, resulting in lower emissions (Scope 3) compared to a conventional DCU. A comparison of estimated reduction in CO₂ and SO₂ production is provided in Figures 4 and 5 . Furthermore, most modern refineries have a DCU to convert residues into light distillates and coke. Ind-Coker AT technology can be implemented with the existing DCU as an
60.0
0.6 0.2 0.4 0.8 1.0 1.4 1.2 1.6
Conventional coker Ind - Coker
Conventional coker Ind -C oker
50.0
40.0
30.0
20.0
10.0
0.0
0.0
CO from petcoke, IOCL
CO from petcoke, India
SO from petcoke, IOCL
SO from petcoke, India
CO production scenario on account of p etcoke
SO 2
Figure 4 Reduction in CO₂ production due to reduced coke yield
Figure 5 Reduction in SO₂ production due to reduced coke yield
Refining India
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