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Nitrate fertilisers ThyssenKrupp A company of ThyssenKrupp Technologies Uhde

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Page 1: Nitrate fertilisers - thyssenkrupp Industrial Solutions ... · PDF fileThe Uhde ammonium nitrate neutralisation technology 8 4. ... principles; and maximum plant ... Uhde BASF INCRO

Nitrate fertilisers

Thys

senK

rupp

A companyof ThyssenKrupp

TechnologiesUhde

Page 2: Nitrate fertilisers - thyssenkrupp Industrial Solutions ... · PDF fileThe Uhde ammonium nitrate neutralisation technology 8 4. ... principles; and maximum plant ... Uhde BASF INCRO

Table of contents2

1. Company profile 3

2. Uhde – The right choice 4

3. The Uhde ammonium nitrate neutralisation technology 8

4. The Uhde pugmill granulation process 12

5. Prilling for low-density ammonium nitrate 16

6. Ammonium sulphate nitrate – ASN 18

7. Calcium nitrate – CN 19

8. Liquid N fertiliser – UAN and CN 20

9. Main references 22

Page

The world of fertilisers is almost as extensive as that of agricultural products. As an international technology-based

engineering contractor, Uhde meets the challenge posed with a widerange of key processes for fertiliser production, including ammonia,

nitric acid, nitrogenous and phosphate fertilisers, ammonium nitrateand UAN. More than 360 references in world-scale ammonia, nitric

acid and fertiliser plants bear witness to Uhde’s dedication to providing customers with competitive advantages:

advanced economic and environment-friendly technologies; professional quality-controlled engineering and project execution

principles; and maximum plant reliability.

Uhde – a valuable partner for an entire spectrum of nitrate fertilisers.

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31. Company profile

Uhde’s head office in Dortmund, Germany

With its highly specialised workforce of more than 4,900 employees and its international network of subsidiaries and branch offices, Uhde, a Dortmund-basedengineering contractor, has, to date, successfully completed over 2,000 projectsthroughout the world.

Uhde’s international reputation has been built on the successful application of its motto Engineering with ideas to yield cost-effective high-tech solutions for itscustomers. The ever-increasing demands placed upon process and application technology in the fields of chemical processing, energy and environmental protectionare met through a combination of specialist know-how, comprehensive service packages, topquality engineering and impeccable punctuality.

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2. Uhde – The right choice4

Uhde can look back on morethan 80 years of experience inthe fertiliser sector, during whichtime the company has engin-eered more than 360 plants.

With today’s intensive agricul-ture, soil yields are very mucha matter of choosing the righttype of fertiliser. Selection criteria for the wide range ofdifferent grades now availableinclude soil type, climate andcrop type. This, in turn, reflectsthe need for high-quality fertiliserproduction. Choosing the rightprocess is of the essence.

Uhde offers proven, competitiveprocesses based on both pro-prietary and renowned licensedtechnologies, thus putting usin a position to offer a full rangeof plants for the production ofsingle-component and mixednitrogenous fertilisers.

The diagram on the right (Fig. 1)provides an overview of theprincipal fertiliser productionroutes, as well as the availableprocesses and main licensors.

This brochure deals only withthe key processes offered byUhde for the production ofnitrate fertilisers.

For our urea, nitrophosphate,compound fertiliser, nitric acidand ammonia processes, pleaserefer to our separate brochures.

Urea AN CAN CAN CN

Stamicarbon,UFT

Uhde, INCRO Uhde BASF Uhde

ASN

Uhde

Natural gas Lime stone

NH3

Uhde

HN03

Uhde

Nitrogen fertiliser

NH3CO2 HNO3

CN

UAN

Uhde

Fig. 1:Uhde fertiliser processes

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5

H2SO4

AS NP NP NP MAP DAP SSP TSP

Uhde BASF INCRO YFT, INCRO

NPK NPK NPK

BASF INCRO

Phosphate rock Potassium Sulphur

H2SO4

Monsanto

H3PO4

YFT

Nitro-phos.

BASF

CNconv.

BASF

Compound fertiliser Phosphate fertiliser

NH3

Ca3(PO4)2

H2SO4

Lime AN sol.

H3PO4

YFT: YARA Fertilizer Technology

INCRO: Subsidiary of Intecsa-Uhde/Fertiberia

KCl/K2SO4

YFT, INCROYFT, INCROYFT, INCROYFT, INCRO

YFT, INCROUFT: Uhde Fertilizer Technology

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Insert: 3D plant model

General view of the nitric acid and ammonium nitrate plant for Enaex S.A. in Mejillones, Chile. Capacities: 925 t/day HNO3 (100%) and

1,060 t/day AN prills.

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3. The Uhde ammonium nitrate neutralisation technology

8

Ammonium nitrate neutraliser

Ammonium nitrate neutralisa-

tion is a proprietary Uhde pro-

cess, designed for maximum

reliability and safety. This

well-proven technology is the

basis of our nitrate fertiliser

technology portfolio and has

been used successfully by

our customers in more than

40 commercial-scale plants

for about 4 decades now.

General

Ammonium nitrate is produced from gaseousammonia and aqueous nitric acid in an exother-mic reaction according to the following equation:

NH3 + HNO3 NH4NO3 - ³HR

The heat of reaction is released into the circulat-ing stream of AN solution, causing a temperaturerise. Precise control of the reaction system parameters is essential for highly-efficient ammo-nium nitrate production. These parameters in-clude in particular good mixing in of the reactantsas well as reliable temperature and pH control.The Uhde technology comprises an external circulation loop, either forced or natural, andalso a sophisticated reactant feed and mixingsystem for stable operating conditions.

Uhde offers two proprietary types of neutralisa-tion processes for the production of ammoniumnitrate solution:

Vacuum neutralisation and evaporation

This process is the most popular alternativebecause it involves the lowest investment costs.The reaction takes place in a slightly pressurisedneutraliser to prevent the ammonium nitratesolution from boiling in the mixing and reactionsections thus minimising ammonia losses.

Subsequently, the solution is flashed into avacuum through a restriction orifice adjacent tothe vapour separator, thereby utilising the reac-tion heat for water evaporation. A solution con-centration of 95 wt.% can be achieved with apreheated feed of 60 wt.% nitric acid. For con-trol and safety reasons, however, the AN solu-tion concentration is mostly limited to 92 wt.%.

The higher concentration necessary for furtherprocess steps, such as granulation (Section 4)or prilling (Section 5) is achieved by steam heating the solution under vacuum pressure.For optimum process control and stability, Uhdepreferably applies a thermosyphon evaporationsystem. The scrubbed process vapours are usedfor feedstock preheating; surplus vapours arecondensed.

Pressure neutralisation

In order to utilise the heat of reaction more efficiently, the process vapour system in thiscase operates above atmospheric pressure.Uhde offers two main pressure neutralisation alternatives for effective heat recovery:

a) The heat of reaction stored in the hot ammo-nium nitrate solution leaving the neutraliser isused direct for the final concentration stage.Even if a final concentration of 97wt.% isrequired, there is no need to import additinalsteam. (Fig. 3)

b) Heating steam is imported for final concen-tration of the ammonium nitrate solution,while part of the heat of reaction is utilised togenerate low-pressure steam at approx. 5 barabs. (Fig. 4)

In both cases the flash steam from the vapourseparator at 2 - 4 bar abs is used for inter-mediate concentration of the weak ammoniumnitrate solution. Again, the remaining processvapours are used for feedstock preheating; surplus vapours are condensed. Depending onhow the vapour condensate is to be used, someor all of the vapours need to be scrubbed beforecondensation in a separate vapour scrubber.

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CWCW

Orifice

NH3 gas

HNO3

Clean condensate

Process condensate

for scrubbing/saturation

Process condensate

AN melt

Steam

10 bar

AN

sol

utio

n

NH

3 ga

s

Vapourseparator

ANevaporator

ANneutraliser

Circulation pump

Vapourseparator

Orifice

Vapours to scrubber

Process condensate

for scrubbing/saturation

AN melt

NH3 gas

HNO3

Process condensate to scrubber

Vapourseparator

Firstevaporator

ANneutraliser

Circulation pump

Vapourseparator

Vapourseparator

Finalevaporator

AN melt

Vapours to scrubber

Process condensate to scrubber

Steam

10 bar

Process condensate

for scrubbing/saturation

Steam 5 bar

Boiler feed water

NH3 gas

HNO3

Vapourseparator

Steamboiler

Vapourseparator

Firstevaporator

Finalevaporator

ANneutraliser

9Fig. 2: Vacuum neutralisation and evaporation

Fig. 3: Pressure neutralisation with direct heat recovery

Fig. 4: Pressure neutralisation with clean steam production

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Vapour scrubbing

The vapours formed in the ammonium nitrateneutralisation and evaporation process are scrubbed either direct in the vapour separator orin a separate scrubbing column. Depending onthe quality of the process vapours, a single ordual-stage scrubber is applied. The condensedoverhead vapours from the scrubber can beused for various purposes, e.g. as scrubbingmake-up water or as feed for a demineralisedwater plant. Contaminant levels in the cleancondensate are as low as 15 ppm nitrogen. The sump concentrate can be used for nitricacid make-up.

Pipe reactor process

In this process ammonia and nitric acid aremixed in a long pipe equipped with internals.The heat of reaction immediately produces watervapours which cause a rapid flow through thepipe with a high degree of turbulence. In a down-stream separator the flow is split into vapoursand ammonium nitrate solution. The solution isfed into a flash tank before being pumped to theconcentration stage while the vapours arescrubbed prior to further utilisation. The reactionprocess typically operates at pressures of 4-5 barabs and the vapours can thus be used for furthersolution concentration and other heating purposes.

Uhde has already constructed and successfullycommissioned licensed pipe reactor technology.

CWCW

Steam

Process condendates Clean condensate

Process water for HNO3 plants

Vapours

HNO3

Steam ejector

Steam condenser

Process condensate pump

Scrubber pump

Condenser

Vapour scrubber

Processcondensate tank

Fig. 5: Vapour scrubbing

Uhde can also offer a

third-party ammonium

nitrate process, for example

the INCRO pipe reactor

process, if required.

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Consumption figures (expected)

Vacuum Pressure neutralisation Pugmill

neutralisation granulation

2 bar abs with direct 4 bar abs with clean AN 33.5

heat recovery steam production CAN 27

Fig. 2 Fig. 3 Fig. 4 Fig. 6

Steam import (4.5/10 bar a) kg/tAN 130 10 52 90

Steam export (6.5/4.5 bar a) kg/tAN - - 240

Cooling water m3/tAN 31.0 22.5 3.8 5.0

Electrical energy kWh/tAN 2.0 3.8 4.8 29.0

Ammonia kg/tAN 213 213 213

Nitric acid kg/tAN 789 789 789

Remarks: Figures for 60 wt.% nitric acid feed, 96 wt.% AN product, cooling water at ³T = 10°C, electrical energy without DCS, lighting, CR AirCon, limestone grinding, etc.

Ammonium nitrate vacuum neutralisationand evaporation unit for Enaex S.A. inMejillones, Chile. Capacity: 1,060 t/day AN solution

(92/96 wt.% AN)

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4. The Uhde pugmill granulation process12

General

Today modern fertiliser plants supply granulatedproducts. Prilling is becoming less common due toenvironmental constraints and increased productquality requirements.

In producing fertiliser from the various solid andliquid feed materials, the granulation unit mustensure that the resulting product meets marketrequirements with regard to its chemical andphysical properties.

There are many different ways of producing granules, such as flaking, drum, pan or pugmillgranulation and fluid-bed technology.

In the past, Uhde has built granulation plants forall common fertiliser grades from straight N fertil-iser to NP(K) and P(K) fertilisers. Uhde has awealth of experience in the design and operationof granulation plants and is in a position to buildplants based on all modern granulation processes.

The most common granulation process used in nitrate fertiliser plants built by Uhde is theproprietary Uhde pugmill granulation process.

AN granules

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AN/CAN pugmill granulation plant, Fertiberia S.A. (formerly Enfersa) in Sagunto/SpainCapacity: 1,100/1,400 tpd (33.5 wt.%/26 wt.% N)

Pugmill granulation unit for the Irish Fertilizer Company (IFI) in Arklow, Ireland.Capacity: 1,400 t/day CAN granules (27.5 wt.% N)

CAN granules

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The Uhde pugmill granulation process

The core component of Uhde’s own granulationprocess is a pugmill granulator. A pugmill orblunger is a horizontal mixing and agglomerationdevice. Its design is based on a horizontal U-typetrough with dual shafts and paddles extendingthe length of the trough. The rotation of the pitched paddles moves the product from thebottom of the trough up through the centre. Asa result of the speed at which the paddles rotate,the granules are fluidised in the upper part ofthe granulator.

All solid feeds (e.g. filler or additives) and therecycle material are added at the front of thepugmill to ensure sufficient mixing before theliquids are added. The liquid feed (e.g. ammo-nium nitrate melt) is distributed over the fluidisedmaterial using a proprietary distributor.

In the granulator the material is built up to sizethrough agglomeration and layering. The hot,moist granules leaving the granulator drop througha chute into the rotary drying drum. In the dryingdrum the granules are dried by means of hotair. The dried granules are then screened intooversize, on-size and undersize fractions by double-deck or single-deck screens. The undersizefraction is returned to the granulator immediately;the oversize fraction is crushed beforehand.

The on-size, or product, fraction is cooled in a fluidised-bed cooler with conditioned air to asuitable storage temperature.

The cooled product is then passed to a condi-tioning unit where surface-active substances areapplied to improve the handling and/or transportproperties (e.g. caking, dusting, etc.).

The waste air of the fluidised-bed cooler is usedto dry the product, thus considerably reducing theamount of waste air to be treated. It also reducespower consumption as the products can be driedautothermally or with a significantly reduced heatinput by an air heater installed upstream of thedrying drum.

Most of the dust in the waste air from the dryingdrum is removed by cyclones and returned to thegranulator. After passing through the cyclones,the air still contains dust and ammonia, whichhave to be removed in order to comply withenvironmental regulations.

The waste air from the drying drum and the airfrom the dedusting system are therefore passedto a wet scrubber. Here, the dust is largelyremoved from the air by close contact with thescrubbing solution while the ammonia reactswith the nitric acid contained therein.

The bleed from the scrubber is returned to theevaporation system. Therefore, no liquideffluents are produced during normal operation.

Pugmill granulation unit for ANWIL S.A. in Wloclawek, Poland.Capacities: 1,200 t/day AN granules and

1,500 t/day CAN granules

3D model of Uhde pugmill granulation

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AN solution

AN granules

Uhde pugmill granulator

15

Key features

• Flexible with regard to capacity

• Flexible with regard to production of different products e.g. AN, ASN, CAN, CN

• Easy addition of supplementary nutrients (S, Mg, etc.)

• Capacity – installed single-line capacity from 200 to 1,800 mtpd

• Emissions below BAT levels

• No liquid effluents

• Power consumption below 30 kWh/t (depending on product)

• Low air flow

to atm.

Bleed

(to evaporation)

Clean condensate

Cond. air

Coating agent

HNO3

Scrubber

Screens

Crushers

Fluidised-bed coolerPugmill granulator

Coating drum

Drying drum

Cyclones

AN/CAN

Ste

am

Ste

am

Additive

AN melt

Filler(limestone, dolomite)

Fig. 6: Uhde pugmill process

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The prills are then sequentially dried in two rotatingdrums, screened, cooled in a fluid-bed cooler andcoated with an anti-caking agent. Off-specmaterial is redissolved and recycled to the process.All air used in the process is scrubbed to meetBAT emission levels. By reusing the cooling airin the drying drums, energy consumption andwaste air flow are significantly reduced.

Uhde has designed LDAN prilling plants withsingle-line operating capacities of 1,250 mtpdand engineered licensed processes of up to1,060 mtpd.

Uhde cooperates closely with INCRO in the fieldof LDAN prilling technology.

5. Prilling for low-density ammonium nitrate16

AN melt

Prilling additive

Prilling tower

Prilling airscrubber

Drying airscrubber

Conditioned air

Anti-caking agent

Screens

Bucketelevator

Scrubber bleed

to evaporation

AN prills

Coating drum

Fluidised-bed cooler

Steam Steam

Pre-drying drum Drying drum

Fig. 8: Uhde LDAN prilling process

Ammonium nitrate prilling unit forQueensland Nitrates Pty Ltd., Australia.Capacity: 400 t/day AN prills

(technical grade)

Low-density ammonium nitrate (LDAN) is usedas an effective and cost-efficient mining explosive,mainly as a mixture with fuel oil (ANFO) or inemulsion-type explosives. The high porosity ofthe LDAN allows good oil absorption, which isnecessary for an optimal blasting energy yield.If no additives are used, chemically pure ammo-nium nitrate can be produced, e.g. as feedstockfor medical purposes (nitrous oxide).

Main characteristics of the final LDAN prills:

• Uniform spherical shape

• Nitrogen content > 34.7 wt.%

• Water content < 0.1 wt.%

• Grain size 1 - 2 mm

• Fuel absorption > 6 wt.% (adjustable)

• Free-flowing

• Good thermal resistance to hot climates

For the production of low-density prills theammonium nitrate melt is pumped to the prillingtower top and mixed with a prilling additive.From here the melt is sprayed in droplets whichcrystallise in a countercurrent stream of cool air.

Although prilling plants for

fertiliser-grade ammonium

nitrate have decreased in

importance compared to

granulation processes, prilling

is still the state-of-the-art

process for low-density

ammonium nitrate.

Uhde offers a proprietary

technology as well as quali-

fied engineering services for

licensed processes.

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6. Ammonium sulphate nitrate – ASN18

Orifice

ASNAir

NH3 gas

HNO3

HNO3

CW

Vent

to process

Process condensate

HNO3

to saturator

to atm.

Dedusting

from points

Scrubber Scrubber

Drying drum Fluidised-bed cooler

Granulator

ASN conversion

Screen

Crusher

AS (case by case)

Al2(SO4)3

FeSO4

H2SO4 (80 – 90%)

NH3 gas

Steam

Air

CW

Fig. 9: Ammonium sulphate nitrate process

The depletion of sulphur in soils is increasingand this has spurred demand for sulphur-con-taining fertilisers, such as ammonium sulphatenitrate.

This is particularly attractive as it can be pro-duced in a modified AN or CAN pugmill granula-tion plant.

Ammonium sulphate nitrate is a double salt which approximately corresponds to the followingformula:

2 NH4NO3 x (NH4)2SO4

Commercial-grade ammonium sulphate nitratecontains 26% nitrogen and 14% sulphate.

In the Uhde process described below, theammonium nitrate combines with ammoniumsulphate to form ammonium sulphate nitrate.The addition of additives results in a productwhich is very hard and has excellent storageproperties.

An approx. 85% AN solution is fed to a saturatortogether with sulphuric acid and gaseous NH3.The ammonium sulphate nitrate melt is formedby the neutralisation of the sulphuric acid withgaseous NH3 at approx. 160°C.

The heat of reaction liberated through the formation of ammonium sulphate vaporises watercontained in the feedstock, thereby causing theammonium sulphate nitrate solution to reachthe required final concentration.

The ammonia-bearing vapours from the saturatorare treated in a scrubber, where the ammonia isremoved by reaction with nitric acid. The scrubberbleed is returned to the saturator.

ASN can be granulated in a pugmill granulationunit as described on page 14.

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7. Calcium nitrate – CN

Ground limestone and nitric acid of 50 - 60%concentration are mixed in agitated tanks. The components react to form calcium nitratesolution according to the following equation:

CaCO3 + 2 HNO3 Ca(NO3)2 + H2O + CO2

The CO2 and water vapours liberated by thereaction are withdrawn, and any entrained droplets are removed by the scrubbing system.

Commercial-grade calcium nitrate (CN) containsapproximately 5 - 7% ammonium nitrate toimprove storage properties. The required ANcontent can be obtained by neutralising theremaining free acid with ammonia or by addingfresh ammonium nitrate solution.

If CN is used to produce liquid fertiliser, an evap-oration step is not needed. Any inerts or othercomponents of the limestone that do not reactwith nitric acid have to be removed by filtration.The remaining sludge is disposed of.

If granulated product is required, the calciumnitrate solution is sent to an evaporator to obtainthe concentration required for granulation.

CN can be granulated in either a drum or pug-mill granulation unit to yield well-shaped roundgranules, the appearance of which is similar tothat of calcium ammonium nitrate granules.(see page 14).

The calcium nitrate melt is fed to the granulatorvia a metering station along with the recycledmaterial (the fines, the crushed oversize, andthe dust from the dust-collecting facilities).

The granules are then air-cooled in a cooler.

The cooled product is screened, and the on-sizefraction is bagged or sent to the bulk storage area.

The waste air from the cooler is treated in a wetscrubber before being discharged to atmosphere.

CN solution from nitrophosphate production

The nitrophosphate (ODDA) route for the production of NP(K) fertiliser produces CN solutionas a by-product. This solution, too, can be usedto produce CN granules or liquid CN fertiliser.

19

HNO3

NH3 gas

CaCO3

Process condensate

Additive

Sludge

CW

to solution

Process condensate

CN granules

Steam

Vapour separator

Evaporator

Granulator

CN conversion unit

Cooling/Drying Drum

Scrubber

Screen

Crusher

Fig. 10: Calcium nitrate process

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8. Liquid N fertiliser – UAN and CN

20

CW

NH3 gas

Urea solution

HNO3

Process condensate

UAN solution

Corrosion

inhibitor

NH

3 ga

s

AN

sol

utio

n

Orifice

CW

Process condensate pump

Vapourseparator

ANneutraliser

UAN solution tank

UAN cooler

Circulation pump

Ammoniaheater

UAN solution pump

Condenser

Processcondensate tank

UAN

The use of liquid fertilisers is a common practice,especially in North America. A fertiliser withexcellent physical properties is UAN solution, whichis a mixture of ammonium nitrate, urea and water.Standard solutions contain 28, 30 and 32% nitrogen, respectively, but can also be enrichedwith soluble plant nutrients, such as sulphur,boron and calcium compounds. A typical com-position of UAN solution with 32% N is

AN : Urea : H2O = 45 : 35 : 20%

As UAN solution is a liquid with a low viscosity,it can easily be applied by spraying without theneed for additional irrigation. Depending on itscomposition, the salting-out temperature of thesolution can be well below zero degrees centi-grade and transport and storage are thus simpleeven in cold climates.

Uhde has designed UAN plants based on twoprocess alternatives:

a) UAN solution on the basis of ammonium nitrate neutralisation

In this process alternative ammonium nitrate isproduced as described in Section 3. Urea solutionand water are mixed with the AN solution in aspecial UAN mixing unit to obtain the requirednitrogen content and adjusted to an alkaline pH.After cooling and the addition of a corrosioninhibitor, the final UAN solution can easily bestored and handled.

Fig. 11: UAN solution process with ammonia gas

Fertiliser complex for CF Industries Inc. in Louisiana, USA including

a 2,000 t/day urea plant, a 870 t/day nitric acid plant, a 1,105 t/day AN plant and a 2,450 t/day UAN solutio plant.

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21

CW

CW

Urea off-gas

Urea solution

HNO3

UAN solution

Corrosion inhibitor

Clean condensate

AN

sol

utio

n

HNO3

UAN solution tank

Vapourseparator

Off-gasscrubber

Processcondensate tank

AN neutraliser

b) Neutralisation of urea off-gas

When implementing a once-through urea synthesis, the ammonia-rich off-gas can be usedto drive the ammonium nitrate neutralisationreaction. Due to the high CO2 content in the off-gas, the neutralisation reaction is performedin a natural circulation loop, followed by the UANpreparation steps described before. In order tominimise the ammonia losses in the vent gas, a sophisticated scrubbing system is installed,reducing the losses to 0.013 kgAN/tAN.Contaminant levels in the process condensateused as make-up water for a nitric acid plantare as low as 300 ppm AN and 100 ppm HNO3.

CN

Calcium nitrate solutions are non-pressurisedliquids mainly used for drip or irrigation systemsin horticulture. A typical solution is CN-17 with a composition AN : CN : H2O = 31 : 36 : 33%.This solution is a fast-acting fertiliser containingboth nitrate (for quick response) and ammoniumnitrogen (for retarding nutrition) while the calciumbuffers the pH in the soil.

The production of AN and CN is described indetail in Section 3 and 7, respectively.

UAN solution plant for CF Industries Inc.in Louisiana, USA UAN off-gas vent scrubber

Fig. 12:UAN solution process with urea off-gas

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9. Main references22

AN/CAN/CN granulation plants

Completion Customer Plant site Raw Process Nitrogen Capacity Remarksmaterials content

% mtpd Final Products

2000 ANWIL SA Wloclawek, Poland AN solution, dolomite Uhde Pugmill Granulation 33.5 1,200 AN Granules or

27 1,500 CAN Granules

1999 Irish Fertilizer Industries (IFI) Arklow, Ireland AN solution, dolomite Uhde Pugmill Granulation 27.5 1,400 CAN Granules

1999 AZOCHIM S.A. Piatra Néamt, Romania AN solution, dolomite Uhde Pugmill Granulation 33.5 700 AN Granules or

26 1,000 CAN Granules

1993 Sasol Fertilizers Secunda, South Africa AN solution, dolomite Uhde Pugmill Granulation 28 1,600 CAN Granules

(reconstruction)

1991 Abu Qir Fertilizers and Abu Qir, Egypt AN solution, dolomite Fluidised-bed Granulation 33.5 2 x 1,200 AN Granules

Chemical Industries Co. (HFT)

1989 Chemie Linz Linz, Austria AN solution and CaCO3 Drum Granulation (BASF) 28 1,800 CAN Granules

from CN conversion

1988 GNFC Bharuch, India AN solution and CaCO3 Uhde Pugmill Granulation 26 475 CAN Granules

from CN conversion

1987 ENFERSA Sagunto, Spain AN solution, Uhde Pugmill Granulation 33.5 1,100 AN Granules or

dolomite/limestone 26 1,400 CAN Granules

1987 Quimigal Alverca, Portugal CN solution Uhde Pugmill Granulation 15.5 150 CN Granules

AN prilling plants

Completion Customer Plant site Raw Process Nitrogen Capacity Remarksmaterials content

% mtpd Final Products

2010 Orica Australia Pty. Ltd. Bontang, Indonesia AN-solution Prilling (Uhde) 34.8 970 AN Prills

2007 CSBP Ltd Kwinana, Australia AN solution Prilling (Uhde) 34.8 1,060 LDAN Prills

1999 Queensland Nitrates Pty Ltd Moura, Australia AN solution Prilling (KT) 34.8 400 LDAN Prills

1999 Enaex S.A. Mejillones, Chile AN solution Prilling (KT) 34.8 1,060 LDAN Prills

1996 TNC Thai Nitrate Co. Rayong, Thailand AN solution Prilling (KT) 34.8 220 LDAN Prills

1993 VBC Industries Visakhapatnam, India AN solution Prilling (Norsk Hydro) 34.5 240 AN Prills

1983 Empresa Pública Cachimayo, Peru AN solution Uhde Prilling 34.5 220 LDAN Prills (exp.)

Industrial Cachimayo

1977 CIL Inc. Carseland, Canada AN solution Uhde Prilling 34.8 680/1,250 LDAN Prills

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Nitrogen solution plants

Completion Customer Plant site Raw Process Nitrogen Capacity Remarksmaterials content

% mtpd Final Products

2010 Orica Australia Pty. Ltd. Bontang, Indonesia HNO3, NH3 Uhde Vacuum Neutralisation 990 AN solution

Evaporation

2010 Orica Australia Pty. Ltd. Bontang, Indonesia LDAN solution UAN Mixing 145 UAN solution 29 % N

Urea solution

2009 Ferrostaal Point Lisas, Trinidad HNO3, NH3, Uhde Vacuum Neutralisation 1,920 AN Solution

and Tobago AUM-Project Urea UAN Mixing 4,300 UAN solution 32 % N

2007 Nitrogenmuvek Rt. Petfürdö, Hungary HNO3, NH3 Uhde Vacuum Neutralisation 1,100 AN solution

& Concentration

2006 Abu Qir Fertilizers Abu Qir, Egypt AN solution UAN mixing 1,000 UAN solution 32% N

and Chemical Industries Co. Urea solution

2004 Saskferco Products Inc. Belle Plaine, Canada HNO3, NH3, Uhde Vacuum Neutralisation 255 AN solution

Urea solution UAN Mixing 565 UAN solution 32% N

1999 Enaex S.A. Mejillones, Chile HNO3, NH3 Uhde Vacuum Neutralisation 1,060 AN solution

& Concentration

1999 The Mauritius Chemical & Port Louis, Mauritius NH3, HNO3 Uhde Vacuum Neutralisation 225 AN solution

Fertilizer Industry Ltd (MCFI)

1998 CF Industries Inc. Donaldsonville, USA HNO3, NH3, Uhde Atmospheric Neutralisation 1,105 AN solution

Urea solution Uhde UAN Mixing 2,450 UAN solution 32% N

1994 CF Industries Inc. Donaldsonville, USA HNO3, NH3, Uhde urea off-gas Neutralisation 1,460 AN solution

Urea offgas Uhde UAN Mixing 3,250 UAN solution 32% N

and solution Offgas scrubbing

1991 Abu Qir Fertilizers Abu Qir, Egypt HNO3, NH3 Uhde Vacuum Neutralisation 2 x 1,150 AN solution

and Chemical Industries Co.

1990 Kemira Tertre, Belgium NH3, HNO3 Pressure Neutralisation 2,100 AN solution

(Kemira Carnit Process)

1987 ENFERSA Sagunto, Spain HNO3, NH3 Uhde Pressure Neutralisation 1,100 AN solution

& Concentration

1987 Quimigal Alverca, Portugal HNO3, NH3, Ca(NO3)2 Quimigal/Uhde Process 135 CN solution

1983 Insomnia Construction (Pty) Ltd. Sasolburg, South Africa HNO3, NH3 Uhde Vacuum Neutralisation 800 AN solution

& Concentration

1978 PAKARAB Fertilizer Ltd. Multan, Pakistan NH3, HNO3 Uhde Vacuum Neutralisation 700 AN solution

& Concentration

1977 CIL Inc. Carseland, Canada HNO3, NH3 Uhde Vacuum Neutralisation 680 AN solution

& Concentration (1,250)

1977 CF Industries Inc. Donaldsonville, USA HNO3, NH3, Uhde Atmospheric Neutralisation 600 AN solution

Urea solution Uhde UAN Mixing 1,330 UAN solution 32%N

* AN solution capacity as 100% AN

Specialities

Completion Customer Plant site Raw Process Nitrogen Capacity Remarksmaterials content

% mtpd Final Products

2002 Gujarat State Fertilizers Sikka, Jamnagar, India Ammonia, Sulphuric INCRO pipe reactor 1,320 DAP

and Chemicals Ltd. Acid, Phosphoric Acid (diammonium phosphate)

2001 Gujarat State Fertilizers Sikka, Jamnagar, India Ammonia, Sulphuric INCRO pipe reactor 230 DAP

and Chemicals Ltd. Acid, Phosphoric Acid (diammonium phosphate)

1980 Bandirma Gübre Fabrikalari A.S. Bandirma, Turkey NH3, H2SO4 Uhde Crystallisation process 21 600 AS

1973 Nitrogenous Fertilizer Industries Ptolemais, Greece NH3, HNO3, H2SO4 Uhde Pugmill Granulation 26 580 ASN

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