Experts in air filtration

cleanNOx
UREA SKIDS

Our in house designed cleanNOx skids are designed to reduce the NO and NO2 in the gas stream to meet the requirements of the Industrial Emissions Directive (was the Waste Incineration Directive).

Also known as a Selective Non-Catalytic Reduction system (SNCR) solution, these systems are used to remove harmful oxides of nitrogen from hot flue gases by reaction with urea or ammonia solutions. Filter designs use urea because of the relative minimal COSHH issues when compared to handing ammonia.  The urea solution is injected inside combustion chamber outlets or secondary (dwell) chambers and are mainly used in power plants that burn biomass or municipal or clinical waste.

NOx injection can be a fine art as there are certain limitations required for optimal dosing these are:

  • Gas temperature needs to be between 790°C - 1050°C
  • Ideally 850°C to 950°C for optimum efficiencies
  • Spray pattern and duct distribution
  • Lance design

We offer two different types of cleanNOx skids which are categorised as a ‘basic’ skid which uses urea solution in IBC container and needs to be integrated into a clients controls system, or the full ‘prill ‘skid which has its own control system and uses pellets of prill, mixing with de-mineralised or towns water on site.

By using our reagent waste calculator we can determine the quantity of urea needed and recommended the skid to suit. It is n OPEX/CAPEX balance over the life of the plant which steers the decision with our clients.

IBC cleanNOx urea skid

This is our basic urea dosing system is mainly used when only small amounts of urea need to be dosed 0-20l/min which is a small compact skid which uses  IBC's (intermediate bulk containers) of urea solution (picture).  The limitation is not the pumps, but at this upper rate of 20l/hr the IBC container will need to be changes every 48 hours.

The skid is a small stainless steel control cabinet and uses a small pump to send urea to the lance. This system can be equipped with 2 pumps and can run multiple lances if required. As the urea enters the lance the compressed air is mixed and creates a fine mist inside the dosing chamber.

This sort of skid can be quickly retro fitted into a plant with minimal downtime.

Prill cleanNOx urea skid

This cleanNOx urea skid is mainly used when only large amounts of urea need to be dosed 20lmin - 100l/min. This large skid Uses urea prill which is mixed with demineralised or towns water to create a urea solution. This way of dosing urea is cheaper operationally than the IBC’s and it also allows you to change the urea concentration should you have any spikes of NOx.

The large skid has two built in control panels one to house all the pumps and dosing equipment and the other is to provide all the controls hardware / software with its own HMI which can be integrated into the sites SCADA system.

Again this system could also be retro fitted in to a plant.

If you would like more information or if you have any enquiries about our cleanNOx range of urea skids, or indeed any of our other products please don’t hesitate to give us a call on 01858 419104 or complete the enquiry form.

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Our recent Projects

We were contracted to provide 2 small Ceramic filters suitable for a small volume but with a design maximum temperature of 600°C. In addition the filters will be handling a syngas which cannot be mixed with oxygen so an alternative to compressed air would need to be used for the ‘Cleanpulse’ cleaning of the 25 Ceramic element in each of these CPC78 filters. In addition dosing of small amounts of a re-agent is required so the client also opted for a ‘Cleandose’ 25kg bag skid. Find out more about Project CAD below.

Project SF2 - CleanPulse cartridge filter system with spark arrest box and control panel

Project BCI - Bag Filter, Gas Suspension Absorber, Reagent Dosing for a Challenging Carbon Process

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