APPLICATION FORM

for the

The European Responsible Care Award 2008

of

CEFIC

APPLICANT’S PARTICULARS

Company

Name of the company: DSM Agro

PO Box: Postbus 291

Post code and town: 6160 MG Geleen, the Netherlands

Contact person: Martin Voorwinden

Post: Technology Manager – Fertilizers

Tel.: (+31) 046 476 9647

E-mail: martin.voorwinden@dsm.com

PREMISES, COMPANY, LOCATION

DSM Agro B.V. has production plants both on the Chemelot site in Geleen and on the Corus

site in IJmuiden, the Netherlands. The head office is in Sittard. The company manufactures

and sells nitrogen-containing fertilizers, as well as industrial products, such as ammonia and

nitric acid. DSM Agro is part of Royal DSM N.V. in Heerlen, the Netherlands.

TITLE OF SUBMISSION

World record in the reduction of the greenhouse gas nitrous oxide

in nitric acid plants

TITLE OF SUBMISSION

World record in the reduction of the greenhouse gas nitrous oxide in nitric acid plants

DESCRIPTION AND PURPOSE

Introduction

DSM Agro has four nitric acid plants in operation: two at Geleen (NL), and two at IJmuiden

(NL). Nitric acid is made from ammonia and is used as a starting material in the production

of nitrogen-based fertilizers, such as calcium ammonium nitrate. Nitrous oxide (laughing gas

or N2O) is formed in this process as an undesirable by-product. Until recently, it was

released into the atmosphere from the chimney stack of the plant with the waste gases. Our

four plants make over 1 million tonnes of nitric acid a year, which involves the formation of

7000-7500 tonnes of N2O.

Like carbon dioxide (CO2), N2O is a greenhouse gas, but its greenhouse effect is 310 times

stronger than that of carbon dioxide. The N2O emission in question is therefore equivalent to

the emission of almost 2.3 million tonnes of CO2.

We at DSM Agro have been looking for a method to reduce this N2O emission for years. For

example, we have managed to improve the platinum catalyst in the nitric acid process in

order to increase the conversion of ammonia (NH3) into nitric oxide (NO), which cut the

formation of N2O by about 15-20%. To reduce it further, we needed a method for the

catalytic decomposition of N2O into harmless nitrogen and oxygen. We conducted

experiments over many years, aimed at designing a suitable catalyst for the decomposition

of N2O in cooperation with various Dutch institutes such as the Energie Centrum Nederland

(ECN) and the Universities of Delft, Eindhoven and Utrecht. We installed a relative large

pilot-scale reactor in our nitric acid plant in IJmuiden, using ECN’s N2O catalyst, and

conducted test runs with it for over a year, with reasonable success. Unfortunately, these

favourable results came too late, because in the meantime new N2O- reducing techniques

appeared on the market. It is true that the majority of these techniques were also still in the

development stage and the results were patchy, but in some cases they gave good results

over a fairly long period of time.

CO2 trading

At the same time, we had talks with the Dutch Ministry of Environment (VROM) and with

Yara, the other manufacturer of fertilizers in the Netherlands, to discuss an “opt-in”, which

would make it possible to include N2O in the Emission Trading Scheme (ETS). With this opt-

in in the National Allocation Plan (NAP), it has been possible since January 1, 2008 to

include the reduction of the N2O emission in the environmental obligations under the Kyoto

Protocol for 2008-2012.

It has been agreed in consultation with the Dutch authorities that instead of taking the

historical emission of about 7.5 kg of N2O per tonne of nitric acid as the basis of the

emission regulations, a benchmark value of 1.8 kg per tonne would be taken for this purpose

comparable with the IPPC level for Best Available Technology (BAT). (Remark: In the

meantime this benchmark value of 1.8 kg is in March 2008 not accepted by the EU-

commission and the Dutch authorities have presented a new proposal with a decreasing

value of 1.7 – 1.3 kg per tonne over the trading period 2008-2012). This made it clear that

we had to be reasonably certain about the technical feasibility in order to avoid buying the

rights to a very large amount of emission.

Choice of techniques

There are basically two techniques for reducing the amount of N2O formed in a nitric acid

plant, namely:

1) secondary technology, in which an N2O-decomposing catalyst is placed in the

existing reactor that operates with a platinum catalyst, and

2) tertiary technology, in which a completely new reactor is placed in the path of the

waste gases going to the stack.

Secondary technology, in which the existing reactor is used, needs less investment, but its

results are very unpredictable, not to speak of the other risks and disadvantages involved.

Tertiary technology calls for a large investment and a long down time for installation, but

promises a substantial cut in the N2O emission. It seemed that this would be further helped

in particular by the fact that two of our four nitric acid plants operate with a very high waste

gas temperature of about 500°C.

We had a dilemma on our hands in September 2006, as we had to choose between two

solutions. The tertiary technique involved a large investment of more than 10 million Euros,

and a complex modification of our existing plants, but promised a chance to recoup some of

the cost by emission trading and ensured the best available N2O technology in the long run.

The secondary solution called for low investment but could not guarantee for certain the

required reduction to 1.8 kg of N2O per tonne of nitric acid. The choice was particularly

difficult, because we did not have a definite National Allocation Plan at the time with an opt-

in for N2O, and certainly no approval yet from the European Commission for our opt-in

request.

We chose the best technique available – the tertiary technology from Uhde - for our two

largest plants in the belief that the problem of global warming would call for even stricter

measures in the future. This technique was less attractive in the case of the other two

smaller plants for both technical and economic reasons. Therefore we opted here for a

commercially available secondary technology from an independent supplier (Heraeus). To

be able to operate the Emission Trading Scheme, all our plants had to meet the demands of

the N2O Monitoring Protocol as well. For this purpose, we installed a large number of

instruments, sensors and analyzers in our process plants and in the stacks, so as to be able

to measure the emission accurately, which cost us more than a million Euros.

Results

All our nitric acid plants were upgraded by installing an N2O-reducing technology in the last

quarter of 2007, and since January 1, 2008 they are in compliance with all the monitoring

requirements of the Emission Trading Scheme.

The results are positive and in some cases even exceeded our expectations. Thus, in the

two largest plants, the tertiary technique virtually abolished the N2O emission, ensuring a

100% cut, as against the expected reduction of somewhere around 96%. At present, after

operation for over eight months, there are no signs of slackening in the N2O reduction, and

we hope that this is will continue in future. This is an absolute world record. No nitric acid

plant has ever managed such a reduction in the N2O emission anywhere in the world by this

technology.

We expected a 90% reduction in the other two plants by using the maximum amount of

secondary catalyst. In one of them the current figure is around 80%, while in the other one it

is considerably less, but we are working on improving it.

Savings for the environment

In the last quarter of 2007, DSM Agro reduced the N2O emission of its nitric acid plants by

6500 tonnes of N2O a year in one fell swoop, which is equivalent to 2.0 million tonnes of

CO2 a year, i.e. to the annual CO2 output of 1 million cars or the CO2 uptake of 500 million

trees, in other words, a forest the size of the Dutch Province of Limburg, thereby doubling

the effect of trees in the Netherlands as a whole.

Postscript

In August 2008 the European Commission still has not reached a decision about the Dutch

request for an opt-in. However, the environment cannot wait, so DSM Agro has taken the

responsible initiative to develop and implement the right solution.

We hope that the politicians will eventually decide to include N2O in the emission trading, so

that more companies can follow DSM Agro’s example and reduce the N2O emission by

scores of millions of tonnes of CO2 equivalents all over Europe.

At the end of September 2008 the European Commission approved the Dutch request for an

opt-in (postscript October 2008)

Author’s signature: M. Voorwinden

Date: August 2008

Attachments: 2 pictures

Foto 1: Nitric acid plant #5 in Geleen, with new N2O reactor at left side of building

Foto 2: Official opening of N2O project on 31 March 2008 by Dutch minister of Environment

Jacqueline Cramer. Left: Renso Zwiers, President DSM-Agro

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