{"id":20636,"date":"2017-06-16T10:17:28","date_gmt":"2017-06-16T14:17:28","guid":{"rendered":"https:\/\/www.tun.com\/blog\/?p=20636"},"modified":"2021-05-21T12:24:05","modified_gmt":"2021-05-21T16:24:05","slug":"loughborough-university-invents-technology-to-reduce-hazardous-diesel-engine-emissions","status":"publish","type":"post","link":"https:\/\/www.tun.com\/blog\/loughborough-university-invents-technology-to-reduce-hazardous-diesel-engine-emissions\/","title":{"rendered":"Loughborough University Invents Technology to Reduce Hazardous Diesel Engine Emissions"},"content":{"rendered":"

A <\/span>recent study<\/span><\/a> by The International Council of Clean Transportation<\/span> found that increased air pollution from diesel nitrogen oxide (NOx) emissions led to 107,600 early deaths in 2015. <\/span>The study also found that actual NOx emissions are higher than the emissions reported by manufacturers, the difference referred to as \u201cexcess NOx emissions.\u201d Of the early deaths in 2015, excess NOx emissions accounted for 38,000 early deaths. Uncorrected, worldwide early deaths from diesel NOx emissions could rise to 183,600 in 2040, an alarming thought.<\/span><\/p>\n

But do not fret! <\/span>Graham Hargrave<\/span><\/a>, professor of optical diagnostics at <\/span>The Wolfson School of Mechanical, Electrical and Manufacturing Engineering<\/span><\/a> at Loughborough University in the UK, and Jonathan Wilson, research associate, have developed the world\u2019s first technology that could significantly cut NOx emissions from diesel engines. <\/span><\/p>\n

Their technology, named <\/span>Ammonia Creation and Conversion Technology<\/span><\/a> (ACCT), is the <\/span>only existing technology<\/span><\/a> that could accomplish the task. <\/span><\/p>\n

Current technology found wanting<\/b><\/span><\/h5>\n

Up until now, vehicle manufacturers have been relying on <\/span>AdBlue<\/span><\/a>\u2122, a solution of water and urea, to help remove NOx emissions from diesel engines. <\/span><\/p>\n

When AdBlue\u2122 is injected into the exhaust system, it vaporizes and decomposes to form ammonia and carbon dioxide before entering the Selective Catalytic Reduction (SCR) system. Once it enters the SCR, the ammonia breaks down the NOx into water and nitrogen, which are then released through the exhaust. Water and nitrogen, as we know, are harmless.<\/span><\/p>\n

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AdBlue\u2122 sounds wonderful, so why not continue to use it? <\/span><\/p>\n

The problem is, AdBlue\u2122 is effective only at high exhaust temperatures exceeding 250\u00baC or 482\u00baF. But exhaust temperatures don\u2019t always reach that high. <\/span><\/p>\n

As Wilson explained to TUN, <\/span>internal combustion engines in diesel vehicles reject a lot of heat during their operation in two ways. <\/span><\/p>\n

Firstly, the engines are designed to be kept cool, so heat is rejected by means of a radiator. <\/span><\/p>\n

Secondly, heat is expelled through engine exhaust. <\/span><\/p>\n

\u201cAs engines have become more efficient, we have made use of some of this energy to power other system components, most notably turbochargers, which increase overall engine efficiency,\u201d said Wilson. <\/span><\/p>\n

\u201cThe energy that remains is given to aftertreatment components, which mostly require heat to operate.\u201d <\/span><\/p>\n

So while it\u2019s great that engines have become more efficient, the result is that \u201cthey also produce more NOx (before the aftertreatment components) and have lower and lower exhaust temperatures.\u201d <\/span><\/p>\n

Since AdBlue\u2122 needs high exhaust temperatures to work effectively, it doesn\u2019t work well in urban areas with stop-and-go traffic or construction sites. <\/span><\/p>\n

\u201cUnfortunately with many vehicles doing short stop\/start journeys, such as buses and construction vehicles, many engines never reach the optimal temperature required for the SCR systems to operate efficiently,\u201d Hargrave said in a statement. <\/span><\/p>\n

If the SCR systems can\u2019t work efficiently, then more NOx is being released into the urban environment, especially in large cities. <\/span><\/p>\n

\u201cWe are all familiar with the \u2018cold start\u2019, where diesel vehicles spew out plumes of toxic emissions before their catalytic systems are up to temperature and able to work effectively,\u201d said Hargrave.<\/span><\/p>\n

What makes the problem worse is that <\/span>the use of AdBlue\u2122 at lower temperatures results <\/span>in an accumulation of secondary products (other undesirable chemicals) over time, which ultimately leads to exhaust blockage and engine failure.<\/span><\/p>\n

ACCT accomplishes what<\/b> AdBlue\u2122 can\u2019t<\/b><\/span><\/h5>\n

With the advent of ACCT, however, lower exhaust temperatures will no longer thwart the efficient reduction of NOx from diesel engines. ACCT, an AdBlue\u2122 conversion technology, is designed to work effectively at lower exhaust temperatures. \u00a0<\/span><\/p>\n

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The inventors designed ACCT so it could be <\/span>installed downstream of all the aftertreatment components, and will be the last piece of exhaust hardware before the gases are released from a vehicle\u2019s tailpipe<\/b>. ACCT\u2019s placement means that no heat is extracted from the exhaust that could have been used by any other engine components. <\/span><\/p>\n

Instead, ACCT \u201cis able to use this waste energy to pre-convert AdBlue\u2122 into the ACCT fluid, which is able to be injected instead of AdBlue\u2122 and will never form these deposits,\u201d said Wilson.<\/span><\/p>\n