Environment

The ACCENT™ process from Johnson Matthey offers, for the first time, a fixed bed catalytic technique to remove organic contaminants (pesticides, colour, non-biodegradable organic species, etc.) from aqueous streams. It combines high performance with low operating costs, thanks to its unique design.

 

Uniquely meeting its market’s needs

Although the trend is towards chemical destruction processes, many available technologies are not applicable to most industrial effluent streams. There is also limited choice for low levels of COD (100-5000 ppmw) and low flow rates.

In contrast, any industrial process where organic species in aqueous waste streams cause problems is a potential user of the ACCENT process. It can be applied to both continuous or batch processes in industries such as: bulk/intermediate/effect chemicals, agrochemicals, pharmaceuticals, petrochemicals, textiles, pulp and paper, soaps and detergents, dyes, synthetic resins, petroleum refining (spent caustic treatment), adhesives, pigments, rubber chemicals, food and beverages.

 

Main process features

You can employ the ACCENT process for catalytically enhanced chemical oxidation in stand-alone, pre-treatment or post-treatment roles. There is also a recycle option. It is readily integrated into your existing set-up and is upgradeable, with guaranteed options for exit hypo concentrations of less than 10 ppmw. Fully automated control is available, incorporating self-optimization. You can be sure of optimum selectivity, low levels of hypochlorite and continuous effluent monitoring. Catalyst performance is guaranteed.

The Johnson Matthey HYDECAT^TM process is a catalytic method of removing hypochlorite from chlorinated caustic streams, using a heterogeneous supported nickel catalyst and a modular fixed bed reactor.

 

HYDECAT - one catalyst, three processes

Using HYDECAT 88-2, there are three options for the positioning and design of HYDECAT units to treat waste hypochlorite streams:

• HYDECAT TD - Total destruction - the traditional end-of-pipe application.
• HYDECAT PD - Partial destruction - usually followed by chemical polishing.
• HYDECAT ID - Integrated destruction - in the scrubber liquid recirculation loop.

Chlorine makes a vital contribution to the health and quality of modern everyday life: as a disinfectant and in the manufacture of plastics, pharmaceuticals and many essential products. However, there is increasing pressure to reduce the level of chlorine and chlorinated organic species released to the environment because of the potential effect on the eco-cycle.

Both the public and regulators are highly sensitive to odour nuisance. An unpleasant odour is perceived to be caused by the release of harmful chemicals, but even a 'pleasant' odour can be considered a nuisance if it is of high intensity or persistent.

Odour may arise from the processing of natural products by industries such as food production, tanning, animal rendering and sewage treatment plants. It also originates from the use of chemicals such as solvents in the surface coatings and forming agents prevalent in industries such as printing works, foundries, electronics and in chemical and pharmaceutical manufacture.

Recurring industrial odour problems increasingly provoke local opposition and unfavourable press, attracting the attention of the local regulatory authority. Fines and enforcement notices for non-compliance can be issued, followed by the ultimate sanction of closing the site of persistent offenders, either until the odour nuisance is resolved or permanently.

Our PURAVOC™ range offers a PGM on alumina based fixed bed catalytic technology to remove a broad variety of volatile organic compounds (VOCs) in industrial processes.

Our PURAVOC catalysts provide excellent conversions at low temperatures. This means that, compared to traditional VOC thermal combustion, PURAVOC catalysts give you lower utilities consumption.

PURAVOC catalysts are stable in air at ambient temperature and they can be loaded directly into the reactor. They are supplied pre-activated so no in situ activation is required.