Managing Pollution (AQA A Level Geography)

Technical Innovations to Pollution

• Rapidly developing LDEs and EMEs have some of the highest rates of air pollution and reducing urban air pollution globally, is a challenge

• Strategies include:

  • Technical innovations

  • Vehicle restrictions

  • Government legislation

• Filters

  • Fitted to industrial gas and particulate exhausts, filters carbon out of the gases released during industrial processes

  • Any emitted gases are chemical and pollutant free when released back into the environment

  • Catalytic converters fitted to vehicle exhausts remove harmful pollutants before being released

• Photo-catalytic materials (smog eating material) 

  • Façades are retrofitted to the front of old buildings or new buildings are constructed with photocatalytic concrete

  • Special tiles are coated with titanium dioxide, which is a pigment that acts as a catalyst and is also used in sunscreen

  • When UV rays hit the tiles, a reaction occurs, converting mono-nitrogen oxides (smog producing substances) into less harmful calcium nitrate and water

  • Titanium dioxide within the tiles isn't altered and continues to work indefinitely

• Self-cleaning concrete - Tiocem

  • This is photocatalytic concrete that has titanium dioxide mixed in

  • Buildings will be able to break down nitric and nitrogen oxides when hit by sunlight

  • Can also be used for constructing paving, roofing tiles, roads, and in sound buffering walls on the sides of roads

    • Smog Eating Poem, - the University of Sheffield, UK, has dedicated one of its walls to a smog-eating  poem called In Praise of Air

    • The poem is printed on material infused with titanium dioxide that reduces air pollution

    • The banner removes the pollution of at least 20 cars every day

    • Following this, smog-eating advertising posters have begun appearing in other parts of the world, including a mural made of photocatalytic paint pigments in Warsaw, Poland 

• Greening the urban area

  • Improve air quality through planting trees and vegetation

  • Vertical gardens -  around concrete columns and on the sides of buildings

  • Roof gardens 

  • Urban agriculture using open and derelict spaces

• Air purification towers

  • Dutch designed “Smog Free Tower” which is an air purifying tower that sucks in pollution and expels clean air

  • The first tower was installed in Rotterdam, and cleans 3.5 million cubic metres of air per day

• Self-driving cars

  • Studies have estimated that self-driving vehicles could improve fuel efficiency by 15-40%, which would reduce local emissions of pollutants as well as global greenhouse gases

• Hydrogen fuel additives 

  • Additives improve fuel combustion and reduces emissions in existing vehicles

  • UK developed 'ezero1' technology feeds small amounts of hydrogen into the vehicle air intake, creating a more efficient burn

  • By increasing fuel efficiency, there is an overall reduction in nitrogen oxide (NOx), particulate matter (PM), hydrocarbon and carbon monoxide emissions

  • The technology can be retrofitted to existing vehicles and is available commercially in small numbers

• Alternative fuels

  • Electric 

    • Hybrid electric vehicles (HEVs)

    • Plug-in hybrids (PHEVs)

    • Fully electric (EVs)

  • LPG

    • Dual fuel or bi-fuel vehicles that can switch between LPG and petrol

    • LPG is a by-product of the crude oil refining process 

    • Contains a mix of hydrocarbon gases and considered having a relatively low environmental impact

    • LPG has many uses from cooking to heating, refrigeration to vehicle fuel

  • Synthetic “gas to liquid” (GTL)

    • Shell has developed a new GTL fuel as a replacement for diesel and the engine needs no modification

    • Testing of GTL in heavy vehicles (trucks, buses and ships etc.) and depending on the vehicle age, showed reduced nitrogen oxide (NOx) emissions of 5-37%, and particulate matter (PM) emissions of 10-38%, 

  • Natural gas can also be converted into dimethyl ether (DME) as another alternative to diesel

    • Although the engine needs modifying, using DME reduces NOx emissions by around 25% and PM emissions virtually eliminated

    • Car makers Ford and Volvo, are considering marketing vehicles already able to use DME as a fuel

Vehicle Restrictions & Pollution

• Congestion charge

  • Charges for using vehicles in certain places at certain times (e.g. London's congestion charge)

  • This reduces pollution through the reduction in road traffic (London's emissions dropped 15% in its first year)

  • However, it can increase fringe/outer zone traffic and emissions as people try and avoid the charge by using alternative routes

• Selective bans

  • Certain days and times are designated as no travel times for vehicles

  • Mexico City's air quality is among the worst in the world, according to the World Health Organization (WHO)

  • Over 5 million cars within a valley with a population of more than 21 million people

  • The city instituted a late start for schools 10am instead of 8am

  • No car day, where commuters are banned from using their car depending on the last digit of their number plate (e.g. on Mondays, plates ending in 5 or 6 cannot be used)

• Pedestrianisation

  • Vehicles are restricted from entering certain places at certain times

  • This reduces emission by reducing road traffic

  • Many urban areas have pedestrianised zones, however, it impacts retailers as restrictions on parking can discourage customers

• Park and ride 

  • Buses are laid on by local authorities at the urban fringe and charge a flat fee for all day parking and travel from the parking area to the urban centre

• Improvements to public transport

  • Improved bus services makes accessing areas cheaper, faster and more efficient

  • Many cities have brought in bus lanes, which keeps the buses moving in peak traffic times

  • Trams and light railway services run on lines that avoids congestion

  • Less polluting than buses and can be accessed at various points on the journey

  • Not always successful and can shift congestion issues to the urban fringe

  • Improvements can be very expensive and run over time and budget (e.g. HS2)

• Car sharing/pooling

  • Many urban centres have designated lanes for cars with two or more people in them

  • This keeps the flow of traffic moving and reduces journey times and emissions

Legislation and Pollution

• Legislation can be local or global

• However, according to the UN

• Laws aim to reduce pollution by limiting emissions from industry, private and public facilities and vehicles

• Industries are are regulated under Integrated Pollution Prevention and Control (IPPC) set up under the Pollution Prevention and Control Act of 1999

  • Factories are not allowed to emit 'dark' smoke under the Clean Air Act of 1993, except in unavoidable circumstances (e.g. starting up)

  • The amount of dirt and dust emitted is also strictly monitored/controlled

  • Chimneys must have up-to date modern filters/scrubbers fitted

• In the UK, key air pollutants are regulated by the Air Quality Standards Regulations 2010

• Laws set air quality standards such as:

  • UK Clean Air Act of 1956 and 1968 reduced domestic pollution through the introduction of smoke free zones

  • Industrial pollution was reduced by introducing tall chimney thereby dispersing pollutants higher into the atmosphere

  • Introduction of the MOT emissions test by the Road Vehicles Regulations means all vehicles have to pass an emissions test to be allowed on the UK roads

  • In Scotland, roadside emissions tests are carried out and fines issued if the vehicle fails

  • Local authorities in the UK can issue fines to people leaving their engines running unnecessarily