4 Oct, 2018 RefComm Valencia 1

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1 4 Oct, 2018 RefComm Valencia 1

2 SRU Thermal Reactor Chemistry & Design Roelof ten Hooven Area Sales Manager 4 Oct, 2018 RefComm Valencia 2

3 Company Profile Engineering company specialized in process combustion equipment Founded in 1919 ± 75 employees 4 Oct, 2018 RefComm Valencia 3

4 Goals of the SRU Recover elemental sulfur (S 2-8 ) from all sulfur species in the feed gases (AAG and/or SWSAG). Destruct other harmful components of the feed gases. Limit the formation of new harmful substances. Basically, comply with emissions regulations! 4 Oct, 2018 RefComm Valencia 4

5 QUENCH ABSORBER REGEN Typical Sulfur Recovery Unit ACID GAS COMB AIR MAIN BURNER REACTION FURNACE WASTE HEAT RECOVERY SECTION CONDENSER SULFUR FUEL GAS COMB AIR 1 st LINE BURNER MIXING CHAMBER CATALYTIC CONVERTOR CONDENSER SULFUR FUEL GAS COMB AIR 2 nd LINE BURNER MIXING CHAMBER CATALYTIC CONVERTOR CONDENSER SULFUR FUEL GAS COMB AIR RGG BURNER MIXING CHAMBER REDUCTION REACTOR FUEL GAS COMB AIR INCINERATOR BURNER INCINERATOR CHAMBER WASTE HEAT RECOVERY SECTION 4 Oct, 2018 RefComm Valencia 5

6 QUENCH ABSORBER REGEN Sulfur Recovery Unit Thermal Stage ACID GAS COMB AIR MAIN BURNER REACTION FURNACE WASTE HEAT RECOVERY SECTION CONDENSER SULFUR FUEL GAS COMB AIR 1 st LINE BURNER MIXING CHAMBER CATALYTIC CONVERTOR CONDENSER SULFUR FUEL GAS COMB AIR 2 nd LINE BURNER MIXING CHAMBER CATALYTIC CONVERTOR CONDENSER SULFUR FUEL GAS COMB AIR RGG BURNER MIXING CHAMBER REDUCTION REACTOR FUEL GAS COMB AIR INCINERATOR BURNER INCINERATOR CHAMBER WASTE HEAT RECOVERY SECTION 4 Oct, 2018 RefComm Valencia 6

7 4 Oct, 2018 RefComm Valencia 7

8 Thermal Stage Objectives 65-70% Sulfur Recovery Ammonia Destruction Hydrocarbon Destruction By-product Conversion 4 Oct, 2018 RefComm Valencia 8

9 Sulfur formation in the Reaction Furnace Acid gas Claus reaction: 2H 2 S + SO 2 1½S 2 + 2H 2 O Hydrogen sulfide Sulfur dioxide Sulfur water 4 Oct, 2018 RefComm Valencia 9

10 Sulfur formation in the Reaction Furnace Acid gas Combustion zone H 2 S + 1½O 2 Hydrogen sulfide Oxygen Air Reaction zone SO 2 + H 2 O Sulfur dioxide Water 2H 2 S + SO 2 1½S 2 + 2H 2 O Hydrogen sulfide Sulfur dioxide Sulfur water 4 Oct, 2018 RefComm Valencia 10

11 Acid gas H 2 S H 2 O Sulfur formation Partial H 2 S oxidation ½O 2 ¼O 2 Oxygen Water Sulfur Acid gas H 2 S ½H 2 O ½H 2 Oxygen Water Hydrogen H 2 S cracking H 2 S Acid gas H 2 2H 2 O Hydrogen 2H 2 SO 2 reduction SO 2 Sulfur dioxide 4 Oct, 2018 RefComm Valencia 11

12 Ammonia destruction NH 3 + ¾O 2 ½N 2 + 1½H 2 O 4 Oct, 2018 RefComm Valencia 12

13 Ammonia destruction NH 3 + ¾O 2 ½N 2 + 1½H 2 O NH 3 ½SO 2 Ammonia Acid gas Sulfur dioxide Hydrogen sulfide ½H 2 O Water Air ½N 2 ½H 2 S ¾O 2 Nitrogen H 2 O + Water Ammonia conversion H 2 S oxidation Oxygen 4 Oct, 2018 RefComm Valencia 13

14 Ammonia destruction Remaining NH 3 at MRF outlet: Expected < 20 ppm Guaranteed < 100 ppm Provided: MRF operating temperature > 1300 C (2372 F) Residence time > 1 sec 4 Oct, 2018 RefComm Valencia 14

15 Hydrocarbon destruction CH 4 + 2O 2 CO 2 + 2H 2 O 4 Oct, 2018 RefComm Valencia 15

16 Hydrocarbon destruction Oxidation CS 2 conversion CH 4 CS 2 CO 2 Methane Water 2H 2 O CH 4 + 2O 2 CH 4 conversion Sulfur Carbon disulfide 2H 2 S SO 2 Hydrogen sulfide CO 2 + 2H 2 O Sulfur dioxide Sulfur Carbon dioxide Air Oxygen 2O 2 4 Oct, 2018 RefComm Valencia 16

17 SRU Combustion Basics The degree of combustion depends on 3 factors, the three T s of combustion: Temperature (Residence) Time Turbulence 4 Oct, 2018 RefComm Valencia 17

18 SRU Temperature The overall temperature in the main reaction furnace depends on: Chemical reactions Heat release and absorption The stoichiometry Design conditions (set by process licensor) Pre-heating of the combustion air / acid gas Oxygen enrichment Co-firing of fuel gas Bypassing part of the amine acid gas 4 Oct, 2018 RefComm Valencia 18

19 SRU Residence Time Minimum: determined by reaction kinetics Longer: better destruction of impurities. Residence time section 4 Oct, 2018 RefComm Valencia 19

20 SRU Turbulence The flow pattern determines the shape of the flame, the degree of mixing as well as the flame stability. Mixing is achieved through: Burner geometry E.g. physical restrictions, swirlers, constrictions, etc. Pressure drop Higher pressure drop = more energy! Design principle Pre-mixing vs. diffusion flame principle 4 Oct, 2018 RefComm Valencia 20

21 Resulting Burner Requirements Intense mixing of acid gas and oxygen Recirculation of flue gas 4 Oct, 2018 RefComm Valencia 21

22 LMV Main Burner 4 Oct, 2018 RefComm Valencia 22

23 LMV Main Burner 4 Oct, 2018 RefComm Valencia 23

24 4 Oct, 2018 RefComm Valencia 24

25 LMV Burner Axial Velocity 4 Oct, 2018 RefComm Valencia 25

26 Turbulent combustion 4 Oct, 2018 RefComm Valencia 26

27 4 Oct, 2018 RefComm Valencia 27