Operational experience for the recycling of process water and acids - - PowerPoint PPT Presentation

▶
operational experience for the recycling of process water
SMART_READER_LITE
LIVE PREVIEW

Operational experience for the recycling of process water and acids - - PowerPoint PPT Presentation

Nov 26, 2023 153 likes •584 views

Operational experience for the recycling of process water and acids Realist projects I. Project INDIA (2017) ZLD for rinse water HCl pickling line II. Project China (2017) ZLD for rinse water and spent acid HCl pickling line III. Project

slide-1
SLIDE 1

Operational experience for the recycling

  • f process water and acids

Realist projects

  • I. Project INDIA (2017)

ZLD for rinse water HCl pickling line

  • II. Project China (2017)

ZLD for rinse water and spent acid HCl pickling line

  • III. Project Schweden (2011)

ARP for spent mixed acid pickling line ZLD = Zero Liquid Discharge ARP = Acid Regeneration Plant

1

slide-2
SLIDE 2
  • I. Project INDIA: ZLD for rinse water HCl pickling line

2

slide-3
SLIDE 3
  • I. Project INDIA: ZLD for rinse water HCl pickling line

3

slide-4
SLIDE 4
  • I. Project INDIA: ZLD for rinse water HCl pickling line

4

slide-5
SLIDE 5
  • I. Project INDIA: ZLD for rinse water HCl pickling line

5

HCl/Chloride ppm < 4300 Phosphate ppm < 1100 Sulphate ppm < 8 Iron as Fe-II ppm < 1300 Zinc as Zn-II ppm < 1100 Lead ppm < 20 Cr6+ ppm < 15 BOD ppm <60 COD ppm <350 Total Suspended Solid ppm <150 Total Dissolved Solids ppm <7800

slide-6
SLIDE 6
  • I. Project INDIA: ZLD for rinse water HCl pickling line

6

  • I. conventional waste water treatment
  • II. membrane units / concentration
slide-7
SLIDE 7
  • I. Project INDIA: ZLD for rinse water HCl pickling line

7

slide-8
SLIDE 8
  • I. Project INDIA: ZLD for rinse water HCl pickling line

8

slide-9
SLIDE 9
  • I. Project INDIA: ZLD for rinse water HCl pickling line

9

Ultrafiltration:

  • design: hollow fiber modules
  • 3 modules a 60 m² = 180 m²
  • specific flow ~ 45 – 55 l/m²*h
  • feed pressure ~ 1.5 bar
  • back flushing every ½ h for 30 sec.
  • Chemical Enhanced Backwash (CEB) every 6h for 90 sec.
slide-10
SLIDE 10
  • I. Project INDIA: ZLD for rinse water HCl pickling line

10

Reverse Osmosis I:

  • design: spiral wound module
  • 2 pressure pipes 8“ x 6 elements a 36 m² = 432 m²
  • specific flow ~ 13 l/m²*h
  • maximum feed pressure ~ 30 bar
  • feed ~ 6.5 g/l NaCl / ~ 10.5 mS/cm
  • concentrate ~ 20 g/l NaCl / ~ 30 mS/cm
  • permeate ~ 0.1 g/l / ~ 175 µS/cm
  • operation with acid dosing to feed
  • anti scaling dosing
  • chemical cleaning every 7 – 10 days
slide-11
SLIDE 11
  • I. Project INDIA: ZLD for rinse water HCl pickling line

11

Reverse Osmosis II:

  • design: spiral wound modules
  • 2 pressure pipes 4“ x 5 elements a 12 m² = 120 m²
  • specific flow ~ 11 l/m²*h @ 43-48 bar
  • maximum feed pressure ~ 55 bar
  • feed ~20 g/l NaCl / ~ 30 mS/cm
  • concentrate ~ 40 - 45 g/l NaCl / ~ 53-56 mS/cm
  • permeate ~ 0.2 g/l / ~ 350 µS/cm
  • chemical cleaning every 7 – 10 days
slide-12
SLIDE 12
  • I. Project INDIA: ZLD for rinse water HCl pickling line

12

  • III. thermal concentration
slide-13
SLIDE 13
  • I. Project INDIA: ZLD for rinse water HCl pickling line

13

slide-14
SLIDE 14
  • I. Project INDIA: ZLD for rinse water HCl pickling line

14

Special feature: condensation and heat transfer

slide-15
SLIDE 15
  • I. Project INDIA: ZLD for rinse water HCl pickling line

15

slide-16
SLIDE 16
  • I. Project INDIA: ZLD for rinse water HCl pickling line

16

slide-17
SLIDE 17
  • I. Project INDIA: ZLD for rinse water HCl pickling line

17

Summary:

  • recovery of 85 - 90% of the waste water as high quality fresh water
  • low amount of final dry by product
  • pre concentration of sodium salts in 2 step reverse osmosis unit
  • final thermal concentration in corrosion resistant columns
  • simple thermal concentration process
  • in combination low thermal energy consumption
  • nly thermal concentration:

~ 0,65 kWh/kg combined UO / thermal process: ~ 0,13 kWh/kg → for rinse water from HCl pickling lines or similar application

slide-18
SLIDE 18

II: Project China: ZLD for rinse water and spent acid HCl pickling line

18

slide-19
SLIDE 19
  • II. Project China: ZLD for rinse water and spent acid HCl

pickling line

19

slide-20
SLIDE 20
  • II. Project China: ZLD for rinse water and spent acid HCl

pickling line

20

rinse water spent acid design flow 1.5 0.75 m³ /h HCl/Chloride 23 180 g/l Phosphate 3,25 g/l Iron as Fe-II 7,5 120 g/l Zinc as Zn-II 2,5 g/l NaOH 5 g/l MnO2 2 g/l KMnO4 1 g/l

slide-21
SLIDE 21
  • II. Project China: ZLD for rinse water and spent acid HCl

pickling line

21

slide-22
SLIDE 22

Project China: ZLD for rinse water and spent acid HCL pickling line

22

slide-23
SLIDE 23
  • II. Project China: ZLD for rinse water and spent acid HCl

pickling line

23

slide-24
SLIDE 24
  • II. Project China: ZLD for rinse water and spent acid HCl

pickling line

24

slide-25
SLIDE 25
  • II. Project China: ZLD for rinse water and spent acid HCl

pickling line

25

slide-26
SLIDE 26
  • II. Project China: ZLD for rinse water and spent acid HCl

pickling line

26

slide-27
SLIDE 27
  • II. Project China: ZLD for rinse water and spent acid HCl

pickling line

27

slide-28
SLIDE 28
  • II. Project China: ZLD for rinse water and spent acid HCl

pickling line

28

Batch treatment mixer (commissioning):

  • filling & mixing
  • 90 kg CaCO3
  • 50 kg cement
  • dosing concentrate & mixing
  • 82 l (~ 107 kg) concentrate

→ total batch time ~ 5 minutes → further optimization & reduction cement of dosing by operator after commisissiong

slide-29
SLIDE 29
  • II. Project China: ZLD for rinse water and spent acid HCl

pickling line

29

Summary:

  • ZLD for rinse water and spent acid
  • recovery of ~ 95% of the waste water as fresh water
  • thermal concentration in corrosion resistant columns
  • high volumetric concentration ratio Cf,V= 14 - 23
  • simple thermal concentration process
  • heat recovery by heat transfer condensation – evaporation
  • low investment costs compared to WWTP & HCl - ARP

→for rinse water & spent acid from hydrochloric pickling lines or similar application →HCl ARP available? →re use / discharge of residual dry product ???

slide-30
SLIDE 30
  • III. Project Schweden: ARP for spent mixed acid pickling

line

30

Steuler Total Acid Regeneration STAR

Pickling Line Micro- filtration Bag House Filter Absorp- tion HF/DeNOx Nano- filtration Evapo- ration Crystalli- zation Belt Filter Metal

  • xid

Waste Gas Roaster

slide-31
SLIDE 31
  • III. Project Schweden: ARP for spent mixed acid pickling

line

31

Improvement by Steuler Total Acid Regeneration STAR

◼ free acid separation and metal fluoride concentration in upstream membrane units ◼ crystallization and dewatering of metal fluoride crystalls ◼ low water evaporation in roaster ◼ reduction of natural gas consumption ◼ almost no HNO3 in metal fluoride filter cake → high HNO3 recovery ◼ reduction of chemical consumption

→reduction of operation costs

slide-32
SLIDE 32
  • III. Project Schweden: ARP for spent mixed acid pickling

line

32

Technical design data

waste acid origin stainless steel strip pickling line metal built up step 1: 135 kg/h step 2: 220 kg/h waste acid flow rate step 1: up to 8,500 l/h step 2: up to 13,500 l/h temperature 55 - 65 °C waste acid components 125 - 250 g/l HNO3 total 40 - 80 g/l HF total 30 g/l Metals HF recovery > 96% HNO3 recovery > 92%

slide-33
SLIDE 33
  • III. Project Schweden: ARP for spent mixed acid pickling

line

33

slide-34
SLIDE 34
  • III. Project Schweden: ARP for spent mixed acid pickling

line

34

tank farm microfiltration unit nanofiltration unit

slide-35
SLIDE 35
  • III. Project Schweden: ARP for spent mixed acid pickling

line

35

evaporation bag house filter top of the roaster vacuum belt filter crystallization / chiller

slide-36
SLIDE 36
  • III. Project Schweden: ARP for spent mixed acid pickling

line

36

metal fluoride filter cake vacuum belt filter

slide-37
SLIDE 37
  • III. Project Schweden: ARP for spent mixed acid pickling

line

37

Steuler Roaster:

  • feed flow up to approx. 700 l/h
  • diameter 1.550 mm
slide-38
SLIDE 38
  • III. Project Schweden: ARP for spent mixed acid pickling

line

38

slide-39
SLIDE 39
  • III. Project Schweden: ARP for spent mixed acid pickling

line

39

Special features

◼ HF regeneration efficiency HF > 96% / HNO3 regeneration efficiency > 92% ◼ metal regeneration > 98% with very low fluoride concentration < 0.8% ◼ low energy consumption ~ 1.800 MJ/m³ acid (approx. 60% of common Roaster) ◼ very low waste water flow and nitrate emission ◼ operation at part load with approx. 75 % energy consumption at 60% metal removing ◼ operation with volume reduction (waste acid / regenerated ~ 95%) ◼ extension from 135 kg/h to 220 kg/h metal separation with quite low additional costs ◼ reuse of internal water from chemical pumps and vacuum pump ◼ high requirements for safety, operation and maintenance

slide-40
SLIDE 40
  • III. Project Schweden: ARP for spent mixed acid pickling

line

40

Comparison of Operation and Financing Costs

Project: AVESTA OUTOKUMPU Currency: € Operation time 8000 h/a Generell metal separation 135 kg/h 220 kg/h Neutralization Common Roaster STAR metal concentration 30 g/l 30 g/l HF-concentration total 60 g/l 60 g/l HNO3-concentration total 180 g/l 180 g/l waste acid volume 4500 l/h 7333 l/h Recovery rate HF 0 % total acid 96 % total acid 96 % total acid Recovery rate HNO3 0 % total acid 60 % total acid 92 % total acid spent acid flow rate 7333 l/h 8600 l/h 13000 l/h Operation costs price unit consumption costs consumption costs consumption costs Ca(OH)2-consumption 95 % 70 €/t 1,63 t/h 113,94 € /h 0,425 t/h 29,73 € /h 0,177 t/h 12,39 € /h H2O2-consumption 35 % 210 €/t 0,00 t/h 0,00 € /h 0,43 t/h 90,30 € /h 0,000 t/h 0,00 € /h sludge disposal 33 % 100 €/t 3,88 t/h 388,00 € /h 0,040 t/h 4,02 € /h 0,061 t/h 6,08 € /h water consumption 100 % 0,13 €/t 23,61 t/h 2,95 € /h 8 t/h 1,00 € /h 2 t/h 0,25 € /h waste water 100 % 2,5 €/t 23,61 t/h 59,03 € /h 2 t/h 5,00 € /h 0,5 t/h 1,25 € /h electric power 0,04 €/KWh 35 KWh/h 1,40 € /h 680 KWh/h 27,20 € /h 1000 KWh/h 40,00 € /h cooling water 0,04 €/t 0 t/h 0,00 € /h 550 t/h 22,00 € /h 0 t/h 0,00 € /h compressed air 0,01 €/Nm³ 0 Nm³/h 0,00 € /h 460 Nm³/h 4,60 € /h 240 Nm³/h 2,40 € /h natural gas Hu= 91,3 MJ/Nm³ 0,5 €/Nm³ 0 Nm³/h 0,00 € /h 360 Nm³/h 180,00 € /h 200 Nm³/h 100,00 € /h ammonia 25 % 0,13 €/kg 0 kg/h 0,00 € /h 635 kg/h 79,38 € /h 150 kg/h 18,75 € /h lime modules 100 % 1 €/kg 0 kg/h 0,00 € /h 0 kg/h 0,00 € /h 4 kg/h 4,00 € /h spare parts (of invest) 3,5 %

  • f invest costs

0,00 € /h 54,69 € /h 63,44 € /h sum running costs 565,31 € /h 497,92 € /h 248,56 € /h Benefit HF reduction benefit 72 % 900 €/t 0,00 € /h 0,582 t/h 524,20 € /h 0,568 t/h 511,00 € /h HNO3 reduction benefit 63 % 130 €/t 0,00 € /h 1,112 t/h 144,61 € /h 1,798 t/h 233,75 € /h metal oxide benefit 100 % 0,5 €/kg 0,00 € /h 220 kg/h 110,00 € /h 220 kg/h 110,00 € /h sum benefits 0,00 € /h 778,81 € /h 854,75 € /h financing costs interest rate 3,5 %/a equipment life time 10 a financing costs total 0,00 € /h 1.503.017 €/a 171,58 € /h 1.743.500 €/a 199,03 € /h costs per year 4.522.505 € /a savings per year 5.397.005 € /a 7.779.784 € /a

slide-41
SLIDE 41
  • III. Project Schweden: ARP for spent mixed acid pickling

line

41

  • 20.000.000
  • 10.000.000

10.000.000 20.000.000 30.000.000 40.000.000 50.000.000 60.000.000 70.000.000 1 2 3 4 5 6 7 8 9 10

savings in €

year of operation

common Roaster STAR process

slide-42
SLIDE 42

Operational experience for the recycling

  • f process water and acids

42

Many thanks for your attention