Prilled Urea- A Cost Prilled Urea- A Cost Effective Way to Feed the Effective Way to Feed the WorldWorld

Sule AlabiJonathan AranaElizabeth MoscosoOleg Yazvin

Mentor: Dan Rusinak – Middough

Team EchoTeam Echo

104/20/23

Table of Contents•Purpose

•BFD Overview of Urea Plant

•Process Description

•Sinks & Loads

•Sizing and Costing

•Conclusion

•Q & A 2

Purpose:◦ Convert shale gas

into a nitrogen-based fertilizer

Plant Location: ◦ Williston Basin

Reason for Location: ◦ Bakken Shale Gas

Formation

3

Urea- Solution & Prill Urea has a high nitrogen content (47%)

Liquid Urea (72.0wt%) - Urea Ammonium Nitrate (UAN 32)

Prilled Urea (99.8wt%)- Controlled release fertilizer

Overall Reaction:

◦ Overall Exothermic: -120 BTU/mol

CO2 2NH 3 NH2COONH 4

NH2COONH 4 Urea H2O

4

Cooling Water from CHP Plant

Prilled Urea (99.8%)

Product

BFD of Urea & Prill PlantBFD of Urea & Prill Plant

Air Out

Urea Solution (72%)

Condensate Water with NH3, CO2 & Impurities

Solid Urea (99.8%)

Output NH3 Purge & Urea Solution

To Amm. Nitrate & UAN Plants

Urea Productio

n PlantWaste Water

Treatment Plant

Evaporator Unit

Inlet NH3 & CO2

from NH3 Plant

CO2 & NH3 Recycled Gas

Air In

Prilling Tower

5

Cooling Water from CHP Plant

Prilled Urea (99.8%)

Product

BFD of Urea & Prill PlantBFD of Urea & Prill Plant

Air Out

Urea Solution (72%)

Condensate Water with NH3, CO2 & Impurities

Solid Urea (99.8%)

Output NH3 Purge & Urea Solution

To Amm. Nitrate & UAN Plants

Urea Productio

n PlantWaste Water

Treatment Plant

Evaporator Unit

Inlet NH3 & CO2

from NH3 Plant

CO2 & NH3 Recycled Gas

Air In

Prilling Tower

6

Urea Production PlantConverts reactants into urea

◦ NH3 and CO2 from Nitrate Plant ◦ Produces 72 wt% Urea solution

Main Components of Plant◦ Reactor◦ Stripper◦ Decomposer◦ Scrubber◦ Absorber

Overall Reaction:

CO2 2NH 3 NH2COONH 4

NH2COONH 4 Urea H2O

7

R-111

163

161

111

173

177

C-141

131

151

187

101

183

185

R-121

193

194 196

195

121

165

V-171

167171

V-161

141

V-181

181

198

197

P-151

175

C-131

191

192

P-191

120

V-185

188

R-101

Urea PFDUrea PFD

8

Urea Production Plant – Sinks & Urea Production Plant – Sinks & LoadsLoads

R-101

R-111

163

161

111

173

177

C-141

131

151

187

101

183

185

R-121

193

194 196

195

121

165

V-171

167171

V-161

141

V-181

181

198

197

P-151

175

C-131

191

192

P-191

120

V-185

188

Unit Type Energy Utility Amount

Reactor Sink1,376

MMBtu/dayCooling Water

1.042 MMGal/day

Stripper Load1,199

MMBtu/day Steam 792 Tons/day

Decomposer Sink1,098

MMBtu/dayCooling Water

0.975 MMGal/day

Scrubber Sink984

MMBtu/dayCooling Water

0.829 MMGal/day

Compressor Load 200 HP Electricity3,576

KWH/day

Energy Saver

Sink

Load

9

Urea Production Plant- AspenMass Balance

◦ No Convergence Recycle streams

◦ Attempted Solution Increased number of iterations- no change Cut recycle streams- Mass Balance Converged

Energy Balance ◦ No Values Given

No Ammonium Carbamate properties within Aspen data libraries

◦ Attempted Solutions Free energy of formation Heat of formation Heat of dissolution in water

◦ Pending Solutions Heat Capacity Component with similar properties

10

Cooling Water from CHP Plant

Prilled Urea (99.8%)

Product

BFD of Urea & Prill PlantBFD of Urea & Prill Plant

Air Out

Urea Solution (72%)

Condensate Water with NH3, CO2 & Impurities

Solid Urea (99.8%)

Output NH3 Purge & Urea Solution

To Amm. Nitrate & UAN Plants

Urea Productio

n PlantWaste Water

Treatment Plant

Evaporator Unit

Inlet NH3 & CO2

from NH3 Plant

CO2 & NH3 Recycled Gas

Air In

Prilling Tower

11

Evaporation SectionEvaporation SectionMultiple-Effect Evaporation under

VacuumIncoming Urea Solution:

◦ 72% Urea, 28% WaterTwo evaporators required

◦ 1st Evaporator: 72% to 94.6% Urea

◦ 2nd Evaporator: 94.6% to 99.8% Urea

12

Evaporator PFDEvaporator PFD

P-200

E-205

E-210

E-215

202

205

250210

220

213

230

225

227

200

215

P-220

207209

240 245

T-250

151

P-217

13

Evaporator ProcessEvaporator ProcessTemp and Pressure are the main

operating parameters

14

Importance of Vacuum Importance of Vacuum PressurePressureMinimization of Biuret (Poison)Lowering of Boiling Point for next

evaporation stageConsequently, reduces steam

load

15

Evaporator- Sinks & LoadsEvaporator- Sinks & Loads

P-200

E-205

E-210

E-215

202

205

250210

220

213

230

225

227

200

215

P-220

207209

240 245

T-250

151

P-217

Unit Type Energy(MMBtu/day) Utility Amount

Evaporators Load 1,376 Steam 792 Tons/day

Condenser Sink 1,299 Cooling Water1.042

MMGal/dayEnergy Saver

Sink

Load

16

Evaporator Aspen Evaporator Aspen SimulationSimulation

17

Evaporator Equipment Costs & Evaporator Equipment Costs & SizingSizing

Particulars Evap1 Evap 2 Condenser

Heat Duty (BTU/hr) 1.7X 10^7 8.7 X 10^6 ---

Area (sq. ft.) 718 563 30

Fluid Urea Solution Urea Solution Cooling Water

Pressure 510 mmHG Vacuum 735 mmHG Vacuum ---

Flow Rate (TPD) 2,568 2,568 25,265

Temp In (F) 221 202 93

Temp Out (F) 202 211 107

Total Direct Cost ($) 102,000 80,000 27,999

Equipment Cost ($) 173,000 136,000 8,000

Total Utility Cost ($) 66,000 52,000 6.46 MM

Total Maintenance Cost ($)

5000 3800 3,000

Total ($) Operating Cost 1.1 MM 860,000 1.2 MM

18

Cooling Water from CHP Plant

Prilled Urea (99.8%)

Product

BFD of Urea & Prill PlantBFD of Urea & Prill Plant

Air Out

Urea Solution (72%)

Condensate Water with NH3, CO2 & Impurities

Solid Urea (99.8%)

Output NH3 Purge & Urea Solution

To Amm. Nitrate & UAN Plants

Urea Productio

n PlantWaste Water

Treatment Plant

Evaporator Unit

Inlet NH3 & CO2

from NH3 Plant

CO2 & NH3 Recycled Gas

Air In

Prilling Tower

19

Prill SectionPrill SectionConverts Urea Melt into PrillMain Components

◦ Prill Tower ◦ Screen◦ Cyclone◦ Bag House◦ Heater◦ Dehumidifier

20

Prill PFDPrill PFDD-320

P-310

M-370

E-375

310

P-305

315

S-350

F-330

350

B-360

320

330

360398

345

325

P-316

370

355

390

210

397

395

301

375

380

F-360

342344

21

Prill Sinks & LoadsPrill Sinks & LoadsD-320

P-310

M-370

E-375

310

P-305

315

S-350

F-330

350

B-360

320

330

360398

345

325

P-316

370

355

390

210

397

395

301

375

380

F-360

342344

Unit Type Energy(MMBtu/day) Utility Amount

Heater Load 1,298 Steam ~1 Tons/dayEnergy Saver

Sink

Load

22

Prill Section Cost and Prill Section Cost and SizingSizingResearch yielded a previously done

mathematical simulation of prilling tower◦From simulation data, airflow and size for

our prilling tower were obtained◦Cost for prilling tower will be

approximated by a similar capacity storage tank

Cyclone and bag house sizing in progress due to potential redesign of prilling tower

23

Potential Redesign of Prilling Tower

Standard Oil Patent Filed in 1978

Uses co-current airstream and fluidized bed

Benefits:◦Less dust

emissions◦Smaller tower

required 24

Cooling Water from CHP Plant

Prilled Urea (99.8%)

Product

BFD of Urea & Prill PlantBFD of Urea & Prill Plant

Air Out

Urea Solution (72%)

Condensate Water with NH3, CO2 & Impurities

Solid Urea (99.8%)

Output NH3 Purge & Urea Solution

To Amm. Nitrate & UAN Plants

Urea Productio

n PlantWaste Water Treatment

Plant

Evaporator Unit

Inlet NH3 & CO2

from NH3 Plant

CO2 & NH3 Recycled Gas

Air In

Prilling Tower

25

Waste Water Treatment Waste Water Treatment PlantPlant For every ton of urea produced 0.3 tons of waste water is produced

Co-Current thermal hydrolysis of urea with steam Main Components:

◦ 1stDesorber ◦ Hydrolyzer ◦ 2ndDesorber◦ 2 HX

Overall Reaction: Reverse of Urea Plant

Overall Endothermic: +58 BTU/mol

Urea H2O NH2COONH

NH2COONH NH 3 CO2

26

Waste Water Treatment Waste Water Treatment PlantPlant

Waste Water Content:◦2- 9 wt% Ammonia◦0.8- 6 wt% CO2

◦0.3-1.5 wt% UreaSimple discharge is a waste of

resources and environmentally harmful

Ammonia is hazardous, toxic, and volatile

Urea promotes algae growth and hydrolyses slowly

EPA Emission Requirements: 10 ppm27

WWTP ProcessWWTP Process

E-401

D-421

400

E-411

410

415

450

E-421

S-445

490

494

P-401

496

492

498

455

E-441

P-411

483

430

D-431

445

420

475

480

440

499

485

405

470

465

185

210

28

WWTP Sinks & LoadsWWTP Sinks & Loads

Unit Type Energy(BTU/HR) Utility Amount

Condenser Sink 34,538Cooling Water 5400Gal/day

Heat Exchanger Sink 280,000

Cooling Water 8100Gal/day

Hydrolyzer Load -1.03*10^7 Steam 354TPD

E-401

D-421

400

E-411410

415

450

E-421

S-445

490

494

P-401

496

492

498

455

E-441

P-411

483

430

D-431

445

420

475

480

192

499

485

405

470

465

Energy Saver

Sink

LoadLoadLoad

Sink

Load

29

WWTP Aspen SimulationWWTP Aspen Simulation

30

WWTP Equipment SizingWWTP Equipment Sizing

UnitTotal Direct

Cost ($)Equipment

Cost ($) Area (sq. Ft.)Heat Duty

(BTU/hr)

Condenser 43,300 8000 7 34,538

Heat Exchanger 1 55,900 9400 47 280,000

Heat Exchanger 2 54,200 9400 43 183,000

Hydrolyzer 260,100 81200 --- -1.03 X 10 ^7

Desorber 1 122800 35100 --- .0012

Desorber 2 98200 15300 --- 0

31

WWTP Equipment Costs WWTP Equipment Costs Total Project Capital Cost 2.25

MillionTotal Operating Cost 1.2 MillionTotal Utilities Cost $42,000/yr

32

Daily EconomicsDaily Economics

33

  Materials Cost (Money We Spend) Amount Overall Cost

NH3 $521.00 Per Ton 891.07 Tons Per Day $464,000 Per Day

CO2 $15.00 Per Ton 1153 Tons Per Day $17,300 Per Day

  Product Price (Money We Get)     Overall Price

Urea to UAN $230.00 Per Ton 836 Tons Per Day $159,700 Per Day

Prilled $570.50 Per Ton 793 Tons Per Day $422,000 Per Day

Profit: $100,000 Per Day

Profit: $37 Million Per Year

ConclusionConclusion

34

• Total Plant Cost: $400 Million• Produce 793 TPD of Prilled Product• Produce 836 TPD of Urea melt for

UAN Plant • Numerous Instances of Efficient

Energy Usages.• Aspen Simulation: Great Start

Thank youQuestions?

35