27 real Fertiliser, Chlor-alkali & Commodity Chemicals questions from the Plant Operations bank, as asked in Indian campus drives and tech interviews. Every question has a verified answer and an AI-tutor explanation on placd — free to start.
1. What is Ammonia synthesis loop?
Junior
A.carbonation of ammoniated brine to precipitate sodium bicarbonate, calcined to Na2CO3, with ammonia recovered by lime and calcium chloride as by-product
B.prilling sprays urea melt down a tower to form small prills; fluidised-bed granulation gives larger, harder granules preferred for bulk blending
C.pipe reactor or pre-neutraliser reacting phosphoric acid with ammonia to an 18-46-0 product with the N:P mole ratio held near 1.8–2.0
D.iron-catalysed reaction of syngas at 150–250 bar and 400–500 °C with about 15% single-pass conversion, chilling to condense product and recycling unreacted gas
2. Which term means: "iron-catalysed reaction of syngas at 150–250 bar and 400–500 °C with about 15% single-pass conversion, chilling to condense product and recycling unreacted gas"?
A.Ammonia synthesis loop — carbonation of ammoniated brine to precipitate sodium bicarbonate, calcined to Na2CO3, with ammonia recovered by lime and calcium chloride as by-product
B.Ammonia synthesis loop — iron-catalysed reaction of syngas at 150–250 bar and 400–500 °C with about 15% single-pass conversion, chilling to condense product and recycling unreacted gas
C.Ammonia synthesis loop — pipe reactor or pre-neutraliser reacting phosphoric acid with ammonia to an 18-46-0 product with the N:P mole ratio held near 1.8–2.0
D.Ammonia synthesis loop — prilling sprays urea melt down a tower to form small prills; fluidised-bed granulation gives larger, harder granules preferred for bulk blending
A.sulphuric acid process converting SO2 in two catalyst stages with intermediate absorption, reaching about 99.7% conversion and low stack SO2
B.chlor-alkali electrolyser with a perfluorinated cation-exchange membrane at about 3 V giving 32% NaOH, chlorine and hydrogen with lower energy than diaphragm cells
C.pipe reactor or pre-neutraliser reacting phosphoric acid with ammonia to an 18-46-0 product with the N:P mole ratio held near 1.8–2.0
D.CO2 or ammonia stripping (Stamicarbon or Snamprogetti) decomposes carbamate at synthesis pressure so recycle needs no gas compression
5. Which term means: "CO2 or ammonia stripping (Stamicarbon or Snamprogetti) decomposes carbamate at synthesis pressure so recycle needs no gas compression"?
A.Urea stripping process — CO2 or ammonia stripping (Stamicarbon or Snamprogetti) decomposes carbamate at synthesis pressure so recycle needs no gas compression
B.Urea stripping process — prilling sprays urea melt down a tower to form small prills; fluidised-bed granulation gives larger, harder granules preferred for bulk blending
C.Urea stripping process — iron-catalysed reaction of syngas at 150–250 bar and 400–500 °C with about 15% single-pass conversion, chilling to condense product and recycling unreacted gas
D.Urea stripping process — modern plant consumes about 7–8 Gcal per tonne, with reforming, CO2 removal and synthesis-gas compression the main energy sinks
A.prilling sprays urea melt down a tower to form small prills; fluidised-bed granulation gives larger, harder granules preferred for bulk blending
B.CO2 or ammonia stripping (Stamicarbon or Snamprogetti) decomposes carbamate at synthesis pressure so recycle needs no gas compression
C.liquefaction and storage under PESO-licensed pressure vessels and tonners, with caustic scrubbers for tail gas and detectors alarming near 1 ppm
D.iron-catalysed reaction of syngas at 150–250 bar and 400–500 °C with about 15% single-pass conversion, chilling to condense product and recycling unreacted gas
8. Which term means: "prilling sprays urea melt down a tower to form small prills; fluidised-bed granulation gives larger, harder granules preferred for bulk blending"?
A.Prilling vs granulation — iron-catalysed reaction of syngas at 150–250 bar and 400–500 °C with about 15% single-pass conversion, chilling to condense product and recycling unreacted gas
B.Prilling vs granulation — chlor-alkali electrolyser with a perfluorinated cation-exchange membrane at about 3 V giving 32% NaOH, chlorine and hydrogen with lower energy than diaphragm cells
C.Prilling vs granulation — carbonation of ammoniated brine to precipitate sodium bicarbonate, calcined to Na2CO3, with ammonia recovered by lime and calcium chloride as by-product
D.Prilling vs granulation — prilling sprays urea melt down a tower to form small prills; fluidised-bed granulation gives larger, harder granules preferred for bulk blending
A.carbonation of ammoniated brine to precipitate sodium bicarbonate, calcined to Na2CO3, with ammonia recovered by lime and calcium chloride as by-product
B.modern plant consumes about 7–8 Gcal per tonne, with reforming, CO2 removal and synthesis-gas compression the main energy sinks
C.chlor-alkali electrolyser with a perfluorinated cation-exchange membrane at about 3 V giving 32% NaOH, chlorine and hydrogen with lower energy than diaphragm cells
D.CO2 or ammonia stripping (Stamicarbon or Snamprogetti) decomposes carbamate at synthesis pressure so recycle needs no gas compression
11. Which term means: "chlor-alkali electrolyser with a perfluorinated cation-exchange membrane at about 3 V giving 32% NaOH, chlorine and hydrogen with lower energy than diaphragm cells"?
A.Membrane cell — prilling sprays urea melt down a tower to form small prills; fluidised-bed granulation gives larger, harder granules preferred for bulk blending
B.Membrane cell — modern plant consumes about 7–8 Gcal per tonne, with reforming, CO2 removal and synthesis-gas compression the main energy sinks
C.Membrane cell — carbonation of ammoniated brine to precipitate sodium bicarbonate, calcined to Na2CO3, with ammonia recovered by lime and calcium chloride as by-product
D.Membrane cell — chlor-alkali electrolyser with a perfluorinated cation-exchange membrane at about 3 V giving 32% NaOH, chlorine and hydrogen with lower energy than diaphragm cells
A.iron-catalysed reaction of syngas at 150–250 bar and 400–500 °C with about 15% single-pass conversion, chilling to condense product and recycling unreacted gas
B.sulphuric acid process converting SO2 in two catalyst stages with intermediate absorption, reaching about 99.7% conversion and low stack SO2
C.modern plant consumes about 7–8 Gcal per tonne, with reforming, CO2 removal and synthesis-gas compression the main energy sinks
D.pipe reactor or pre-neutraliser reacting phosphoric acid with ammonia to an 18-46-0 product with the N:P mole ratio held near 1.8–2.0
14. Which term means: "sulphuric acid process converting SO2 in two catalyst stages with intermediate absorption, reaching about 99.7% conversion and low stack SO2"?
A.Double contact double absorption — pipe reactor or pre-neutraliser reacting phosphoric acid with ammonia to an 18-46-0 product with the N:P mole ratio held near 1.8–2.0
B.Double contact double absorption — sulphuric acid process converting SO2 in two catalyst stages with intermediate absorption, reaching about 99.7% conversion and low stack SO2
C.Double contact double absorption — CO2 or ammonia stripping (Stamicarbon or Snamprogetti) decomposes carbamate at synthesis pressure so recycle needs no gas compression
D.Double contact double absorption — prilling sprays urea melt down a tower to form small prills; fluidised-bed granulation gives larger, harder granules preferred for bulk blending
A.pipe reactor or pre-neutraliser reacting phosphoric acid with ammonia to an 18-46-0 product with the N:P mole ratio held near 1.8–2.0
B.sulphuric acid process converting SO2 in two catalyst stages with intermediate absorption, reaching about 99.7% conversion and low stack SO2
C.iron-catalysed reaction of syngas at 150–250 bar and 400–500 °C with about 15% single-pass conversion, chilling to condense product and recycling unreacted gas
D.modern plant consumes about 7–8 Gcal per tonne, with reforming, CO2 removal and synthesis-gas compression the main energy sinks
17. Which term means: "pipe reactor or pre-neutraliser reacting phosphoric acid with ammonia to an 18-46-0 product with the N:P mole ratio held near 1.8–2.0"?
A.DAP granulation — chlor-alkali electrolyser with a perfluorinated cation-exchange membrane at about 3 V giving 32% NaOH, chlorine and hydrogen with lower energy than diaphragm cells
B.DAP granulation — liquefaction and storage under PESO-licensed pressure vessels and tonners, with caustic scrubbers for tail gas and detectors alarming near 1 ppm
C.DAP granulation — CO2 or ammonia stripping (Stamicarbon or Snamprogetti) decomposes carbamate at synthesis pressure so recycle needs no gas compression
D.DAP granulation — pipe reactor or pre-neutraliser reacting phosphoric acid with ammonia to an 18-46-0 product with the N:P mole ratio held near 1.8–2.0
A.modern plant consumes about 7–8 Gcal per tonne, with reforming, CO2 removal and synthesis-gas compression the main energy sinks
B.prilling sprays urea melt down a tower to form small prills; fluidised-bed granulation gives larger, harder granules preferred for bulk blending
C.carbonation of ammoniated brine to precipitate sodium bicarbonate, calcined to Na2CO3, with ammonia recovered by lime and calcium chloride as by-product
D.pipe reactor or pre-neutraliser reacting phosphoric acid with ammonia to an 18-46-0 product with the N:P mole ratio held near 1.8–2.0
20. Which term means: "carbonation of ammoniated brine to precipitate sodium bicarbonate, calcined to Na2CO3, with ammonia recovered by lime and calcium chloride as by-product"?
A.Solvay soda ash — CO2 or ammonia stripping (Stamicarbon or Snamprogetti) decomposes carbamate at synthesis pressure so recycle needs no gas compression
B.Solvay soda ash — carbonation of ammoniated brine to precipitate sodium bicarbonate, calcined to Na2CO3, with ammonia recovered by lime and calcium chloride as by-product
C.Solvay soda ash — chlor-alkali electrolyser with a perfluorinated cation-exchange membrane at about 3 V giving 32% NaOH, chlorine and hydrogen with lower energy than diaphragm cells
D.Solvay soda ash — iron-catalysed reaction of syngas at 150–250 bar and 400–500 °C with about 15% single-pass conversion, chilling to condense product and recycling unreacted gas
A.chlor-alkali electrolyser with a perfluorinated cation-exchange membrane at about 3 V giving 32% NaOH, chlorine and hydrogen with lower energy than diaphragm cells
B.modern plant consumes about 7–8 Gcal per tonne, with reforming, CO2 removal and synthesis-gas compression the main energy sinks
C.iron-catalysed reaction of syngas at 150–250 bar and 400–500 °C with about 15% single-pass conversion, chilling to condense product and recycling unreacted gas
D.pipe reactor or pre-neutraliser reacting phosphoric acid with ammonia to an 18-46-0 product with the N:P mole ratio held near 1.8–2.0
23. Which term means: "modern plant consumes about 7–8 Gcal per tonne, with reforming, CO2 removal and synthesis-gas compression the main energy sinks"?
A.Ammonia plant energy — carbonation of ammoniated brine to precipitate sodium bicarbonate, calcined to Na2CO3, with ammonia recovered by lime and calcium chloride as by-product
B.Ammonia plant energy — CO2 or ammonia stripping (Stamicarbon or Snamprogetti) decomposes carbamate at synthesis pressure so recycle needs no gas compression
C.Ammonia plant energy — liquefaction and storage under PESO-licensed pressure vessels and tonners, with caustic scrubbers for tail gas and detectors alarming near 1 ppm
D.Ammonia plant energy — modern plant consumes about 7–8 Gcal per tonne, with reforming, CO2 removal and synthesis-gas compression the main energy sinks
A.liquefaction and storage under PESO-licensed pressure vessels and tonners, with caustic scrubbers for tail gas and detectors alarming near 1 ppm
B.modern plant consumes about 7–8 Gcal per tonne, with reforming, CO2 removal and synthesis-gas compression the main energy sinks
C.pipe reactor or pre-neutraliser reacting phosphoric acid with ammonia to an 18-46-0 product with the N:P mole ratio held near 1.8–2.0
D.carbonation of ammoniated brine to precipitate sodium bicarbonate, calcined to Na2CO3, with ammonia recovered by lime and calcium chloride as by-product
26. Which term means: "liquefaction and storage under PESO-licensed pressure vessels and tonners, with caustic scrubbers for tail gas and detectors alarming near 1 ppm"?
A.Chlorine handling — prilling sprays urea melt down a tower to form small prills; fluidised-bed granulation gives larger, harder granules preferred for bulk blending
B.Chlorine handling — carbonation of ammoniated brine to precipitate sodium bicarbonate, calcined to Na2CO3, with ammonia recovered by lime and calcium chloride as by-product
C.Chlorine handling — liquefaction and storage under PESO-licensed pressure vessels and tonners, with caustic scrubbers for tail gas and detectors alarming near 1 ppm
D.Chlorine handling — iron-catalysed reaction of syngas at 150–250 bar and 400–500 °C with about 15% single-pass conversion, chilling to condense product and recycling unreacted gas
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