PERFORMANCE MONITORING OF UREA PLANT Presenter: Muhammad Amin Management Associate (Chemical) 18th Batch

Contents OBJECTIVE INTRODUCTION PERFORMANCE MONITORING ROLE OF PROCESS ENGINEERING OVERVIEW OF UREA PROCESS HP LOOP PERFORMANCE UREA PROCESS INDICATORS CO2 COMPRESSOR HP PUMPS HEAT EXCHANGERS UREA GRANULATION CONCLUSION

Objective To give an overview of Performance Monitoring of Urea Plant which is also part of Technical Monitoring Program (TMP) as executed by Process Engineering

PERFORMANCE MONITORING OF UREA PLANT Introduction Process: Urea Wet: Stamicarbon, Holland Urea Dry: Hydro Agri, Belgium Capacity: Design: 1,670 MTPD Raw Material: Ammonia: 1,110 MTPD Carbon Dioxide: 1,480 MTPD Urea Formaldehyde: 18.0 MTPD Storage capacity : 35000 MT PERFORMANCE MONITORING OF UREA PLANT

Performance Monitoring To collect process data of the entire plant or its components for evaluation. Performance indicators are calculated, highlighted to make aware of equipment running with low or high efficiency. To identify system losses that may be causing cost impact of operation away from design point. For early detection of wear and damage that reduces unnecessary time based inspections and improves availability, operability and efficiency of equipment. Data of deviations from normal operating parameters help to establish, diagnose and predict performance trends that dictate future line of action. PERFORMANCE MONITORING OF UREA PLANT

PERFORMANCE MONITORING OF UREA PLANT Process Engineering Responsible to monitor the performance of operating unit and troubleshoot or diagnose process related problems. Execute Technical Monitoring Program (TMP) and produce report. PERFORMANCE MONITORING OF UREA PLANT

PERFORMANCE MONITORING OF UREA PLANT Process Tools Pressure measurement Temperature measurement Flow measurement Softwares: HYSYS, HTRI etc. PERFORMANCE MONITORING OF UREA PLANT

Overview of Urea Process PERFORMANCE MONITORING OF UREA PLANT

PERFORMANCE MONITORING OF UREA PLANT HP Loop OFF GASES OFF GASES TO ABSORBER RECYCLE CARBAMATE SOL SCRUBBER REACTOR LHS EXPORT HPCC Delta T Steam HP Loop Press Press OFF GASES NH3 CARBAMATE SOL STRIPPER N/C 34% UREA SOL H/U TO RECTIFYING COLUMN CO2 Conversion H/U 54% Urea Sol N/C CO2 PERFORMANCE MONITORING OF UREA PLANT

PERFORMANCE MONITORING OF UREA PLANT HP Pumps HP Ammonia Pump HP Carbamate Pump PERFORMANCE MONITORING OF UREA PLANT

Turbine Steam Consumption PERFORMANCE MONITORING OF UREA PLANT HP Pumps Parameter (design) NH3 Pump Carbamate Pump Flow m3/h 63.2 28.3 Efficiency % 54.4 51.7 Suction Press Kg/cm2g 16.5 3.9 Discharge Press 168.8 149.6 Inlet Temp oC 18 74 Outlet Temp 25 69 Power KW 540 309 Turbine Steam Consumption Kg/h 11369 6432 Turbine RPM 4000 A model of pump is generated in HYSYS. Efficiency and developed head is calculated. Temp, Press, at suction and discharge is recorded. Flow at suction is recorded. Turbine efficiency and steam consumption is also calculated. PERFORMANCE MONITORING OF UREA PLANT

PERFORMANCE MONITORING OF UREA PLANT HP Ammonia Pump PERFORMANCE MONITORING OF UREA PLANT

PERFORMANCE MONITORING OF UREA PLANT HP Carbamate Pump PERFORMANCE MONITORING OF UREA PLANT

CO2 Compressor A model of CO2 Compressor is generated in HYSYS. Efficiency of each stage. Specific steam consumption. Power of steam turbine and train. Temp, Press and Flows. NORMAL CONDITIONS (7228 RPM) Parameter I II III IV Polytropic Efficiency % 81 72 75 62 Inlet Temp OC 43 63 Outlet Temp 201 199 185 140 Outlet Press Kg/cm2g 6 24 76 149 PERFORMANCE MONITORING OF UREA PLANT

PERFORMANCE MONITORING OF UREA PLANT CO2 Compressor PERFORMANCE MONITORING OF UREA PLANT

PERFORMANCE MONITORING OF UREA PLANT Heat Exchangers Heat Duty is calculated OHTC is calculated Delta T Cooling water flow is calculated PERFORMANCE MONITORING OF UREA PLANT

PERFORMANCE MONITORING OF UREA PLANT Heat Exchangers PERFORMANCE MONITORING OF UREA PLANT

PERFORMANCE MONITORING OF UREA PLANT Granulation Bed Temperature 105-110 0C Vacuum -50 mm WC Design Pressure + 1200 mm WC Design Temperature 150 C Header Pressure 1.38-1.40 kg/cm2 Urea Solution Flow rate 75-76 m3/hr Perforated hole diameter and hole angle 2mm, 450 Level in Granulator 55 - 65 % Urea Solution Concentration 96% Urea PERFORMANCE MONITORING OF UREA PLANT

PERFORMANCE MONITORING OF UREA PLANT Granulation Atomization and Fluidization air flow and pressure. Roller crushers. Vibrating screens. UF-85 Granulator Washing. As per final product specification: Product T=50oC, Mo=0.30%, Bi=<1%, FA=>0.38--<0.46% Larger than 4.75 mm should be less than 3 % Between 4.75 mm and 2.3 mm, 95 % granules should fall Smaller than 2.3 mm should be less than 2.0% PERFORMANCE MONITORING OF UREA PLANT

PERFORMANCE MONITORING OF UREA PLANT Conclusion Performance monitoring is very important for smooth and optimum plant operations. Performance monitoring ensures our product is produced with desired specifications. Performance monitoring ensures the timely management of equipment health. PERFORMANCE MONITORING OF UREA PLANT

THANK YOU

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Urea Process Indicators CO2 Conversion Indicates how far the Urea reaction proceeded or used to express how much Urea is formed. Higher N/C increases CO2 conversion. PERFORMANCE MONITORING OF UREA PLANT

PERFORMANCE MONITORING OF UREA PLANT N/C Vs Conversion PERFORMANCE MONITORING OF UREA PLANT

PERFORMANCE MONITORING OF UREA PLANT REACTOR PERFORMANCE MONITORING OF UREA PLANT

PERFORMANCE MONITORING OF UREA PLANT REACTOR PERFORMANCE MONITORING OF UREA PLANT

PERFORMANCE MONITORING OF UREA PLANT REACTOR PERFORMANCE MONITORING OF UREA PLANT

Urea Process Indicators NH3/CO2 ratio This molar ratio is measured at the reactor outlet line (Or Initial mixture). The principle is based on linear relationship of liquid density and N/C. This should be between 2.9-3.0 and indicates the reactor efficiency and also HPCC performance. Higher N/C increases the CO2 conversion. PERFORMANCE MONITORING OF UREA PLANT

PERFORMANCE MONITORING OF UREA PLANT N/C Advantages Environment protection through lower NH3 emissions and a reduction of steam consumption. Faster plant start up. Easier and more stable production possible. Safer than taking manual samples. Operation of synthesis at optimum yield. PERFORMANCE MONITORING OF UREA PLANT

Urea Process Indicators H20/Urea ratio High water content in reactor mixture is not desirable as it shifts the chemical equilibrium to the left side. High H/U ratio decreases the urea formation in reactor or decreases the CO2 conversion. H/U ratio gives an indication of extra water added in synthesis section, typically via carbamate recycle. PERFORMANCE MONITORING OF UREA PLANT

Urea Process Indicators Stripper Efficiency (ALFA) It indicates the stripper performance. Calculated at stripper downstream. PERFORMANCE MONITORING OF UREA PLANT

PERFORMANCE MONITORING OF UREA PLANT STRIPPER PERFORMANCE MONITORING OF UREA PLANT

PERFORMANCE MONITORING OF UREA PLANT STRIPPER PERFORMANCE MONITORING OF UREA PLANT

PERFORMANCE MONITORING OF UREA PLANT STRIPPER PERFORMANCE MONITORING OF UREA PLANT

Urea Plant at FFBL CONSUMPTIONS PER 1000 KG OF UREA PRODUCT QUALITY DESIGNER/ LICENSER (WET) STAMICARBON DESIGNER/ LICENSER (DRY) HYDROAGRI PROCESS (WET) CO2 STRIPPING DESIGN CAPACITY 1670 MT / DAY PRODUCTION APRIL 1999 CONSUMPTIONS PER 1000 KG OF UREA AMMONIA 566 KG CARBONDIOXIDE 733 KG UREA FORMALDEHYDE 9 KG ELECTRICITY 54 KWH STEAM 1552 KG PRODUCT QUALITY NITROGEN 46 % BIURET 0.85 % WATER 0.3 % FORMALDEHYDE 0.5 % FREE AMMONIA 10 ppm

HP CARBAMATE CONDENSATION LP CARBAMATE CONDENSATION BFD HP CARBAMATE CONDENSATION   AMMONIA   ATMOSPHERE  UREA REACTOR   SCRUBBER   ABSORPTION 34 % Urea CARBON DIOXIDE   STRIPPER 56 % Urea   RECTIFICATION LP CARBAMATE CONDENSATION 75 % Urea   EVAPORATION   CONDENSATION DESORPTION HYDROLIZATION 96 % Urea   GRANULATION   STORAGE EFFLUENT GASEOUS LIQUID

Plant Operation at Low Load Since control valves, are sized for a certain max & min flow basis for their smooth operation. Accordingly, if we want to keep product specs in acceptable limits, we have to keep flow rates in that ranges. With lower than 60% plant load, the resident time of solution in synthesis will be higher than normal value and finally will result in increased biuret formation in synthesis loop. If plant load is below 60%, few of the stripper tubes would run dry and falling film will not be there. This will result in higher skin temperature of those tubes resulting in their severe corrosion. PERFORMANCE MONITORING OF UREA PLANT

If plant load is below 60%, few of the stripper tubes would run dry and falling film will not be there in those tubes. This will result in higher skin temperature of those tubes resulting in their severe corrosion. 1-Hp control valves can not work properly lower than 60% load of synthesis. 2-If the plant load is lower than 60% ,the distribution of liquid in HP stripper tubes would be lower than normal value and some of tubes may be run with very thin film and finally will result in higher skin temperature of those tubes resulting in their severe corrosion .

3-with lower than 60% plant load ,the resident time of solution in synthesis will be higher than normal value and finally will result to increase the biuret formation in synthesis loop. The flow controling system i.e. control valves are sized to remain 60-70% open max at design load i.e. 100% of name plate capacity [to have enough margin to cope with emergincies]. Accordingly if we want to avoid / minimize any hunting in control valves [keeping same residance time to avoid distrubance in urea product specifications like biuret, moisture etc.] we have to operate these controling systems at their recommended values i.e. > 30 %. So, the controling system limits the minimum load your plant can bear for keeping your product specifications at optimum / required level.

Urea Reactor To HP SCRUBBER From HPCC To HP Stripper CO2 32.4 % BIURET 0.1 % CO2 17.6 % NH3 30.2 % H2O 17.9% 217741 kg/hr 183 oC From HPCC 22673 kg/hr 183 oC To HP SCRUBBER CO2 20.7 % NH3 68.8 % H2O 4.4 % N2 5.3 % O2 0.7 % To HP Stripper CO2 32.4 % NH3 61.7 % H2O 4.9 % N2 0.9 % 145111 Kg/hr 187 ºC CO2 17.9 % NH3 78.3 % H2O 1.6 % N2 1.9 %

HP Scrubber To Absorber from Carbamate pump From Urea Reactor To HPCC 35529 kg/hr 70 ºC 1811 kg/hr 114 ºC CO2 37.4 % NH3 29.7 % H2O 32.8 % CO2 2.1 % NH3 8.1 % N2 78.8 % O2 10.8 % H2O 0.2 % CO2 20.7 % NH3 4.4 % N2 5.3 % O2 0.7 % H2O 68.8 % To HPCC CO2 39.2 % NH3 38.8 % H2O 22.0 % 22673 Kg/hr 183 ºC From Urea Reactor

HPCC From HP Scrubber From HP Stripper To Urea Reactor 145111 Kg/hr 187 ºC To Urea Reactor 95303 Kg/hr 106 ºC From HP Scrubber CO2 23.2 % NH3 63.7 % H2O 13.1 % From HP Stripper CO2 32.4 % NH3 61.7 % H2O 4.9 % N2 0.9 % CO2 17.9 % NH3 78.3 % H2O 1.6 % N2 1.9 %

PERFORMANCE MONITORING OF UREA PLANT Granulation PERFORMANCE MONITORING OF UREA PLANT

Stripper To HPCC From Urea Reactor To Rectifying Column 170oC 140oC From CO2 Compressor UREA 34.2 % BIURET 0.1 % CO2 17.6 % NH3 30.2 % H2O 17.9% CO2 32.4 % NH3 61.7 % H2O 4.9 % N2 0.9 % 217741 kg/hr 183 oC Urea 55.4 % Biuret 0.3 CO2 10.2 NH3 7.9 H2O 26.2 CO2 94.5 % H2O 0.9 N2 4.0 O2 0.6

PERFORMANCE MONITORING OF UREA PLANT Urea Reactor Design Pressure 162Kg/cm2 Design Temperature 190oC Volume 204 m3 No. of sieve trays 10 PERFORMANCE MONITORING OF UREA PLANT

PERFORMANCE MONITORING OF UREA PLANT HP Stripper Design Pressure (shell) 30 Kg/cm2 Design Pressure (Tube) 166.5 Kg/cm2 Design Temperature 235oC Shell 225oCTubes No of tubes 2400 PERFORMANCE MONITORING OF UREA PLANT

PERFORMANCE MONITORING OF UREA PLANT HPCC Design Pressure (shell) 8.2 Kg/cm2 Design Pressure (Tube) 162 Kg/cm2 Design Temperature 175oC (Shell) 192oC(Tubes) No of tubes 2544 PERFORMANCE MONITORING OF UREA PLANT

Heat Exchangers UH-125 UH-131 UH-133 UH-134 UH-225 UH-251 UH-275