NOx cleaning technology
Reduce your ship’s Nitrogen Oxides emission below the strictest International Maritime Organization’s (IMO) requirements by installing a Yara SCR System.
What is NOx?
The burning of fossil fuels in diesel engines creates toxic Nitrogen Oxides (NOx). NOx emission is known to cause local and global health problems such as lung disease and cancer. NOx emission is also negatively affecting the world’s eco systems and contributes to environmental issues such as acid rain, disrupted vegetation, fog and poor water quality.
Ships are heavy emitters of NOx. Yara delivers environmental technology to clean the NOx emission by up to 99%. The Selective Catalytic Reaction (SCR) system is the only proven technology to clean NOx gases and Yara is the market leader in the industry with close to 1600 maritime SCR systems installed.
NOx reduction with SCR technology
Selective Catalytic Reaction (SCR) is the only technology currently available to fulfil the most strict NOx requirements set by the International Maritime Organization (IMO). NOx is reduced using a SCR catalyst together with the reducing agent – a high purity urea solution. The reagent is sprayed into the exhaust gas upstream of the catalyst where it is converted into ammonia. The ammonia mixes with the exhaust gas and reacts with the NOx molecules on the catalyst surface to form harmless Nitrogen Gas (N2) and water (H2O). Click here to see the SCR system illustrations.
- Over 99% NOx reduction can be achieved – approaching zero emissions of NOx
- No increase in fuel consumption
- No increase in CO2 emissions
Marine SCR facts:
- It has been used globally in maritime applications since the early 1990s
- It is a recommended standard solution for NOx emission reduction in vessels (BAT) and installed in more than 450 vessels
- It is a common standard on vessels operating in Scandinavia, where local taxation schemes encourage emission reduction
- It varies in size dependent on engine size and NOx reduction requirements
- Can be tailored to match the layout of most engine rooms and casings
- Can replace existing silencers on retrofits with specially designed integrated SCR/Silencer units to accommodate space restrictions
- It requires global availability of aqueous urea (reagent), which is used with the technology and requires the vessel to be fitted with tanks for storage of it
- SCR is the only technology that offers a positive solution to the trade-off between fuel consumption and NOx reduction and thus does not increase fuel consumption, CO2 emissions and particulates
- The SCR technology offers a cost efficient and effective alternative to meet the IMO NOx regulations and to avoid local environmental taxes.
Why choose Yara SCR technology
With close to 1600 SCR systems installed on ship engines worldwide, Yara is well grounded in long-standing and sustainable experiences in the field of SCR systems for marine applications. Whether ferries, seismic vessels, fishing trawlers, supply vessels or yachts, we design and deliver efficient and compact systems for NOx reduction.
We are the only company supplying a comprehensive NOx cleansing solution: cleansing technology, chemical reagents and aftermarket services and our NOxCare Marine brand is a complete NOx control solution specifically for our shipping clients. NOxCare Marine includes:
NOxCare Marine SCR System:
- The sensor is small, robust and easily replaceable. It can be installed directly on the stack, together with the analyzer, avoiding unnecessary use of excessive gas piping for sampling
- Applicable to all vessel types and both newbuilds and retrofits
- NOx analyzer can be provided per engine or as multiple device with monitoring to control the cleaning efficiency of the catalyst and to provide data for emission reporting
- The user-friendly system ensures easy operation and maintenance
- An emission reporting module in accordance with IMO’s NOx Technical Code (NTC 2008) can also be supplied
- To save additional space, the silencer can be integrated as part of the catalyst housing
NOxCare 40 Marine
Yara’s NOxCare Marine builds upon decades of expertise in NOx control technology and reagent production and supply. NOxCare 40 is Yara’s own high-purity urea solution delivered according to AUS40 ISO 18611 for NOx reduction in marine SCR systems. Our global supply platform means you have the reagent you require, where and when you need it!
In order to operate, a ship’s SCR system a high purity urea solution is required. The system is sensitive to potential chemical impurities in the urea solution. Even small amounts of contaminants can severely impact the performance of the SCR system and ruin the catalyst elements. The quality of the urea solution needs to be specified to ensure reliable and stable operation of the SCR system. The ISO 18611 series provide the specification of urea solution for quality handling, transportation and storage. Marine urea reagent is non-toxic, safe to handle, transport and store, making it practical for use in maritime vessels equipped with SCR systems.
We do not recommend the use of AUS 32,55%, which is currently used in automotive vehicles, in maritime applications. 32,5% urea solution has a freezing point at -11°C whilst 40% urea solution has a freezing point at 0°C. Onboard vessels, the urea solution tank is normally located below the sea surface level. Consequently, contrary to vehicles’ urea product, it will rarely or never be exposed to temperatures below 0°C and this allows for higher concentration of urea in the solution. This yields better economy for the vessels because less water but more urea is carried.
NOxCare Marine SCR Servicing
A regular and preventive maintenance is a cost-efficient way of maintaining your SCR installation, and its performance in compliance with existing regulations. Your urea consumption can also be optimized by regular checks and fine-tunings. Our team of highly skilled service engineers can provide you with the service and the support you need to run your SCR system at the lowest possible cost.
Yara SCR Services can also provide onboard training and familiarization for the ship’s crew. This will provide them with skills needed for early detection of potential issues, and to identify the reasons behind the operation disturbance. Our experts are always available for assistance to ensure that your system runs smoothly. The result for you is optimal performance and lower operational costs.
Our SCR systems are built to withstand tough conditions and provide reliable, affordable NOx reduction for many years. We help ship owners and operators across the world in SCR commissioning, SCR crew training, SCR maintenance (and spare parts), SCR monitoring and catalyst management in order to ensure the efficient and cost effective operation of their vessels.
According to the International Maritime Organizations (IMO) maritime laws, ships are required to reduce their Nitrogen Oxides emission in certain waters in the world. These areas are called emission control areas (ECA) or NOx emission control areas (NECA). The proven technology to reduce NOx emissions from marine engines is SCR (selective catalytic reduction).
NOx emissions from shipping are increasingly regulated in NECAs (NOx emission control areas). From 2016, new IMO Tier III requirements state that all newbuilds must comply with NOx emission requirements in territorial waters. Canadian authorities and the united states environment protection agency (EPA) is already implementing a Norths American and U.S. Carribean NECA, imposing stringent NOx emission limits.
In October 2016, the Marine Environment Protection Committee (MEPC) in IMO approved the designation of new NECA zones in the Baltic Sea and the North Sea. The new regulations will take affect from 1 January 2021.