WO2018197563A1

WO2018197563A1 - A system for creating clean air zones in polluted areas

Info

Publication number: WO2018197563A1
Application number: PCT/EP2018/060600
Authority: WO
Inventors: Philip Cunningham; Reza Ansarishirvan; Matthew Johnson; Siamak Ardkapan
Original assignee: Airlabs Bv
Priority date: 2017-04-25
Filing date: 2018-04-25
Publication date: 2018-11-01

Abstract

The present invention relates to an air delivery system for providing cleaned and cooled air to a specified zone, such as a street canyon or other public space, comprising a) an air cleaning unit having an inlet and an outlet, wherein the inlet is adapted to receive ambient air or cooled air and the outlet is adapted to provide the cleaned and cooled air or the cleaned air, and b) an air cooling unit having an inlet and an outlet, wherein the inlet is adapted to receive ambient air or cleaned air and the outlet is adapted to provide the cleaned and cooled air or the cooled air; wherein the inlet of the cooling unit is connected to the outlet of the air cleaning unit, or wherein the outlet of the cooling unit is connected to the inlet of the air cleaning unit; or c) a unit for cleaning and cooling air simultaneously, having an inlet and an outlet, wherein the inlet is adapted to receive ambient air and the outlet is adapted to provide the cleaned and cooled air.

Description

A SYSTEM FOR CREATING CLEAN AIR ZONES IN POLLUTED AREAS

FIELD OF THE INVENTION

The present invention relates to an air delivery system including active cleaning and/or cooling and passive structural elements that work together to create a clean air zone.

Moreover, the present invention concerns an air delivery system including active and/or passive elements for providing cleaned air to a specified zone, such as an open space or a semi-open space. Furthermore, the present invention concerns a method of providing cleaned and/or cooled air to a specified zone.

BACKGROUND OF THE INVENTION

Air pollutants, particularly nitrogen dioxide (NO2) and fine particulate matter (PM2.5), represent considerable threats to human health. As an example, an estimated 40,000 premature deaths per year are linked to exposure to poor quality air in the UK and the resulting cost to the UK's businesses, society, and health services, adds up to more than £20 billion per year. According to the World Health Organization, air pollution causes over 7 million deaths annually.

A large proportion of these premature deaths can be attributed to specific components of the pollution including particulate matter, PM, and nitrogen dioxide, N0₂which is produced primarily as a result of combustion processes, with vehicle exhaust emissions being the main source of N0₂ in urban settings. The adverse effects of N0₂ on human health are well documented, and include irritation of the airways, impaired lung function, aggravation of pre-existing asthma, and an increased susceptibility to respiratory infections. The annual mean limit set by the EU is 40 μg/m³ and the mean concentration limit for N0₂ as an hourly average is 200 μg/m³.

Fine particulate matter (PM2.5), is a blanket term to describe any particle with an aerodynamic diameter of 2.5 microns or less. These particles are particularly harmful, as their small size allows them to penetrate deep into the lungs, and in some cases even diffuse into the bloodstream. Particulate matter can consist of a wide variety of components, including acids, organics, metals, and common soil and dust particles, and as such it can produce a multitude of harmful effects on the body when inhaled. Exposure to high concentrations is strongly linked to cardiovascular and cerebrovascular disease. Particulate matter is also known to result in increased respiratory mortality and morbidity due to inflammation and oxidative damage, and long term exposure can result in decreased lung function, increased susceptibility to disease, and exacerbation of pre-existing conditions. In comparison to the larger, less harmful PMio fraction, the annual mean PM2.5 concentration limit is much lower, at 10 μg/m³.

Air purifiers remove pollution such as NO2 and PM2.5. They mainly comprise a fan, one or more filters and a box for housing the fan and the filter. Many filtration methods are known such as mechanical filtration, adsorption and electrostatic filtration and different methods are suitable for different removal tasks. While these systems are used in closed spaces such as car cabins and buildings, they have not been applied to open and semi-open spaces due to technical limitations; it is difficult or impossible to generate enough clean air to beat the wind.

Brace et al. 2016 describe a system for removing particles from outdoor air. However they do not describe a complete system for managing the flow of air in the vicinity of the cleaner in order to achieve high performance in a specified zone.

People in open or semi open spaces, such as in street canyons, shopping streets, restaurants, cafes, clubs, transportation stations and terminals including trains, buses and airplanes', pedestrians in the streets and etc, are exposed to polluted air, from traffic, cooking, industry, and other sources. Existing air purifiers clean either the exhaust of a polluting process or they clean the whole room / area people are in, but there have not been any systems to clean the air in such spaces and provide clean air specifically to people.

SUMMARY OF THE INVENTION

The present invention concerns an air delivery system for providing cleaned and cooled air to a specified zone, such as in a street canyon, comprising a) an air cleaning unit having an inlet and an outlet, wherein the inlet is adapted to receive ambient air or cooled air and the outlet is adapted to provide the cleaned and cooled air or the cleaned air, and b) an air cooling unit having an inlet and an outlet, wherein the inlet is adapted to receive ambient air or cleaned air and the outlet is adapted to provide the cleaned and cooled air or the cooled air, wherein the inlet of the cooling unit is connected to the outlet of the air cleaning unit, or wherein the outlet of the cooling unit is connected to the inlet of the air cleaning unit; or c) a unit for cleaning and cooling air simultaneously, having an inlet and an outlet, wherein the inlet is adapted to receive ambient air and the outlet is adapted to provide the cleaned and cooled air.

In an embodiment, the air delivery system of the present invention comprises a first barrier element having a first side and a second side opposite each other, wherein the barrier element is adapted to block wind hitting the first side and create the specified zone on the second side with reduced or no wind, wherein the air delivery system is adapted to provide cleaned and cooled air in the specified zone.

In a second embodiment, the first barrier element defines an enclosed area that is open to the ambient environment at its top, such as an open-top cylinder, or a circular or polygonal barrier, or a frustum on top of an open-top cylinder, which may have an angled or curved top, windows and doors or an opening in the wall for people to walk through, wherein the barrier element is adapted to prevent air from entering the area.

In a further embodiment the air delivery system of the present invention comprises passive elements, such as a wall, wing, canopy, umbrella, depression, barrier, or street furniture that is designed and placed in order to enhance the performance of the air delivery system. For example, such a system would divert polluted wind away from the clean air zone, generating a recirculating current whose flow is separate from the wind. The effect is to reduce the flow of pollution into the clean air zone and decrease the time required for cleaning and increase the cleaning efficiency.

In a still further embodiment the air delivery system of the present invention comprises active elements, such as a fan, air pump or air curtain that divert air flow in order to separate a region of air from the main flow. This embodiment may in particular work together with the passive elements described above.

In a further embodiment the air delivery system of the present invention comprises multiple air cleaning and/or cooling units supplying air into the clean air zone. These may be oriented to blow air into the clean air zone, or oriented to recirculate air within the zone thereby cleaning it multiple times, or some combination of 'in' and 'recirculate'. An excess of air entering the clean air zone may be used to prevent mixing of polluted air along open surfaces, by deflecting the flow and turbulent mixing of the regions away from the zone.

In a further embodiment, the air delivery system of the present invention comprises a second barrier element having a third side and a fourth side opposite each other, wherein the second barrier element is in a specified distance from the first barrier element, so that the specified zone is located between the second side of the first barrier element and the third side of the second barrier element.

In a further embodiment, the specified zone is a zone for people to reside and is selected from an open space, such as a street, stadium, urban area, or park, or a semi-open space, such as a train station, malls, industrial hall, temple (church, mosque, etc.), airport, conference center, museum, exhibition, lecture hall.

In a still further embodiment, the first and/or second barrier element is selected from a solid physical element, such as a brick wall, a metal plate, a glass wall or plate, or a more virtual element, such as a wind curtain.

In a further embodiment, the specified zone is in a street canyon, such as in a street canyon having a height to width ratio of at least 1, such as at least 2.

In a still further embodiment, the air cleaning unit comprises a filter and a means for driving air over the filter, wherein the filter is adapted to clean ambient air.

In a further embodiment, the air cleaning unit is capable of cleaning ambient air comprising air pollution including exhaust gases, such as NOx and SOx, ultrafme particles, ozone, particulate matter, volatile organic compounds (VOC), urban pollutants, naturally occurring compounds, emissions from traffic, industrial sites (power plants, paint shops, sewage treatment plants, tunnels, air terminals, harbors, ferry terminals), construction sites, natural sources (fires, dust storms), occupational air pollution loads that include hazardous and non-hazardous concentrations of pollution, such as high H₂S concentrations, or high VOC concentrations.

In a still further embodiment, the means for driving air over the filter is selected from a fan and wind power. Typically, wind pressure and convection.

In a further embodiment, the air cleaning unit comprises a gas phase advanced oxidation (GPAO) installation or a filter, such as a filter selected from the group consisting of an active carbon filter, a gas adsorbing filter, an electrostatic filter, and a fiber and/or fabric filter. In another embodiment the filter is a modified active carbon filter.

In a still further embodiment, the air cleaning unit and air cooling unit are located in one housing.

In a further embodiment, the air cleaning unit and air cooling unit are located in separate housings.

In a still further embodiment, the air cleaning unit and the air cooling unit are adapted to be mounted on a vertical wall, and optionally the first and/or second barrier element are adapted to be mounted on a vertical wall.

In a further embodiment, the air cleaning unit and the air cooling unit are adapted to be mounted on any of the barrier elements.

In a second aspect, the present invention relates to an air delivery system for providing cleaned air to a specified zone, such as in a street canyon or courtyard, comprising a) an air cleaning unit having an inlet and an outlet, wherein the inlet is adapted to receive ambient air and the outlet is adapted to provide the cleaned air, and b) a first barrier element having a first side and a second side opposite each other, wherein the barrier element is adapted to block wind hitting the first side and create the specified zone on the second side with reduced or no wind, wherein the air cleaning unit is adapted to provide cleaned air in the specified zone.

In an embodiment of the second aspect, the first barrier element defines an enclosed area that is open to the ambient environment at its top, such as an open-top cylinder, or a circular or polygonal barrier, or a frustum on top of an open-top cylinder, which may have an angled or curved top, windows and doors or an opening in the wall for people to walk through, wherein the barrier element is adapted to prevent air from entering the area, and wherein the air cleaning unit is adapted to provide cleaned air in the specified zone.

In a further embodiment, the air delivery system comprises a second barrier element having a third side and a fourth side opposite each other, wherein the second barrier element is in a specified distance from the first barrier element, so that the specified zone is located between the second side of the first barrier element and the third side of the second barrier element.

In a still further embodiment, the first and/or second barrier element are selected from a solid physical element, such as a brick wall, a metal plate, a glass wall or plate, or a more virtual element, such as a wind curtain.

In a further embodiment, the air cleaning unit is capable of cleaning ambient air comprising air pollution including exhaust gases, such as NOx and SOx, ultrafme particles, ozone, particulate matter, volatile organic compounds, urban pollutants, naturally occurring compounds, emissions from traffic, industrial sites (power plants, paint shops, sewage treatment plants, tunnels, air terminals, harbors, ferry terminals), construction sites, natural sources (fires, dust storms), occupational air pollution loads that include hazardous and non-hazardous concentrations of pollution, such as high H₂S concentrations, or high VOC concentrations.

In a still further embodiment, the means for driving air over the filter is selected from a fan and wind power. Typically, wind convection. Typically, an embodiment for the means for driving air over the filter is selected from one or more of the group consisting of a fan, wind power, thermal convection, flow convection and solar power.

In a further embodiment, the air cleaning unit comprises a gas phase advanced oxidation (GPAO) or a filter, such as a filter selected from the group consisting of an active carbon filter, a gas adsorbing filter, an electrostatic filter, and a fabric filter. In another embodiment the filter is a modified carbon filter.

In a still further embodiment, the air cleaning unit is located in a housing.

In a further embodiment, the air cleaning unit is adapted to be mounted on a vertical wall, and the first and/or second barrier element is adapted to be mounted on a vertical wall.

In a still further embodiment, the air cleaning unit is adapted to be mounted on the first, second or both barrier elements.

In a third aspect, the present invention relates to an air delivery system for providing cooled air to a specified zone, such as in a street canyon or courtyard, comprising a) an air cooling unit having an inlet and an outlet, wherein the inlet is adapted to receive ambient air and the outlet is adapted to provide the cooled air, and b) a first barrier element having a first side and a second side opposite each other, wherein the barrier element is adapted to block wind hitting the first side and create the specified zone on the second side with reduced or no wind, wherein the air cooling unit is adapted to provide cleaned air in the specified zone.

In a fourth aspect, the present invention relates to a method of providing cleaned air and optionally cleaned and cooled air to a specified zone, such as in a street canyon, comprising leading ambient air into an air cleaning system of the present invention.

In an embodiment, a specific temperature of the air outside the specified zone and before entering the air cleaning system of the present invention is lowered by at least 2°C when exiting the air cleaning unit to provide cleaned and cooled air to the specified zone. In a more preferred embodiment the air outside the specified zone and before entering the air cleaning system of the present invention is lowered by at least 3°C. Such as at least 4 °C, e.g. at least 5 °C.

The present invention provides these advantages with the described solution.

Further objects and advantages of the present invention will appear from the following description, and claims.

DESCRIPTION OF THE INVENTION

The invention concerns a flow and density driven system that creates and maintains a clean air zone and thereby provides cleaned air to people in areas with varying wind speed and direction. Such areas are in street canyons with dominant parallel wind or street canyons with wind passing above for instance buildings with direction perpendicular to the street. By using the density of the air to control its flow and delivery and to inhibit convective mixing, which causes a reduction in the area to be cleaned and the amount of clean air that should be provided, the present invention can deliver clean air to where it is needed.

With the present invention, it is possible to cool air down in order to send it down and let it be directed toward for instance a stationary body, such as a building, statue etc, and have it stay there due to decreased convection and turbulent mixing, in order to create a controlled clean air bubble zone and to prevent the body from contributing in increasing air pollution.

The air delivery system of the present invention can be adapted to a control mechanism which regulates the system (in regard to cooling and clean air mass flow rate) when the clean zone volume reaches a desired purity, height and/or volume.

One or more barriers may be used in order to create a clean zone in front of the air cleaning unit to supply cleaned air in street canyons with dominant parallel wind, such as in front of shops, restaurants, cafes, clubs, pedestrian in the streets. The barrier can be physical such as a wall or any kind of wind obstacle or it can be virtual such as a wind curtain. More examples of the barrier are bushes, trees, shrubbery, planter boxes. There can be one barrier installed before the air cleaning unit at street and one more can be installed after the air cleaning unit (second one is optional and is installed to increase clean zone efficiency). The barrier may also create an area, such as a space, that is enclosed on its sides but open to the ambient environment at its top, such as a circular or polygonal wall or barrier or an open-top cylinder with a sloping or curved top, wherein the barrier is designed to prevent or minimize polluted air from entering the space.

With the air delivery system of the present invention, clean air can be injected to relevant areas by adding one or few air cleaning units, and for instance clean air can be created inside the restaurants, shops, cafes and be delivered/injected into the street to create a clean zone.

In a first aspect, the present invention concerns an air delivery system for providing cleaned and cooled air to a specified zone comprising a) an air cleaning unit having an inlet and an outlet, wherein the inlet is adapted to receive ambient air or cooled air and the outlet is adapted to provide the cleaned and cooled air or the cleaned air, and b) an air cooling unit having an inlet and an outlet, wherein the inlet is adapted to receive ambient air or cleaned air and the outlet is adapted to provide the cleaned and cooled air or the cooled air, wherein the inlet of the cooling unit is connected to the outlet of the air cleaning unit, or wherein the outlet of the cooling unit is connected to the inlet of the air cleaning unit; or c) a unit for cleaning and cooling air simultaneously, having an inlet and an outlet, wherein the inlet is adapted to receive ambient air and the outlet is adapted to provide the cleaned and cooled air.

In a first embodiment, the air delivery system for providing cleaned and cooled air to a specified zone comprises a) an air cleaning unit having an inlet and an outlet, wherein the inlet is adapted to receive ambient air or cooled air and the outlet is adapted to provide the cleaned and cooled air or the cleaned air, and b) an air cooling unit having an inlet and an outlet, wherein the inlet is adapted to receive ambient air or cleaned air and the outlet is adapted to provide the cleaned and cooled air or the cooled air, wherein the inlet of the cooling unit is connected to the outlet of the air cleaning unit, or wherein the outlet of the cooling unit is connected to the inlet of the air cleaning unit.

In a second embodiment, the air delivery system for providing cleaned and cooled air to a specified zone comprises c) a unit for cleaning and cooling air simultaneously, having an inlet and an outlet, wherein the inlet is adapted to receive ambient air and the outlet is adapted to provide the cleaned and cooled air.

In a further embodiment, the air delivery system of the present invention comprises a first barrier element having a first side and a second side opposite each other, wherein the barrier element is adapted to block wind hitting the first side and create the specified zone on the second side with reduced or no wind, wherein the air delivery system is adapted to provide cleaned and cooled air in the specified zone. The term "first barrier" is used here to indicate that there may be further barriers, but also indicates one barrier.

The wind may change during the day, and may change direction, in which case it is a further advantage that the barrier element be adapted to block wind from other directions, or that a second barrier element be installed to block wind coming from the opposite side. Furthermore, results have shown that having more general barrier configurations increases the effect of the air cleaning unit or units located within the specified zone.

In a further embodiment, the air delivery system of the present invention comprises a barrier element that defines an enclosed area that is open to the ambient environment at its top, such as an open-top cylinder, or a circular or polygonal barrier, or a frustum on top of an open-top cylinder, which may have an angled or curved top, windows and doors or an opening in the wall for people to walk through, wherein the barrier element is adapted to prevent air from entering the area, and wherein the air cleaning unit is adapted to provide cleaned and cooled air in the specified zone.

The specified distance across the enclosed area, such as the diameter of the circular area or the distance across the polygonal area, can vary depending on the specified zone to be cleaned and the size of such area. For instance, the specified zone is an open or semi-open space, and the distance is from 5 to 20 meters. Typically, the specified distance is from 5 to 30 meters, such as from 10 to 20 meters, such as from 10 to 15 meters. In a still further embodiment, the air delivery system of the present invention comprises a second barrier element having a third side and a fourth side opposite each other, wherein the second barrier element is in a specified distance from the first barrier element, so that the specified zone is located between the second side of the first barrier element and the third side of the second barrier element.

The specified distance between the first and second barrier element can vary depending on the specified zone to be cleaned and the size of such area. For instance, the specified zone is a cafe or restaurant located in a street with tall buildings on each side of the street, and the distance is from 5 to 20 meters. Typically, the specified distance is from 5 to 30 meters, such as from 10 to 20 meters, such as from 10 to 15 meters. In a still further embodiment, both the first and the second barrier elements are present.

In a further embodiment, the specified zone is a zone for people to reside. Typically, the specified zone is selected from an open space, such as a street, stadium, urban area, or park, or a semi-open space, such as a train station, malls, industrial hall, temple (church, mosque, etc.), airport, conference center, museum, exhibition, lecture hall.

In a still further embodiment, the first barrier element is selected from a solid physical element, such as a brick wall, a metal plate, a glass wall or plate. In another embodiment, the first barrier element is selected from a virtual element, such as a wind curtain. In a further embodiment, the first barrier element is selected from a bush, a tree, a shrubbery, or a planter box.

Typically, the first barrier will extend from a wall of a building and have a length that is sufficient to block the wind or at least partially block the wind.

In a further embodiment, the first barrier element has a length from 0.5 to 2 meters, such as from 1 to 1.5 meters, such as about 1.2 meters. In a further embodiment, the first barrier element has a height of from 1.5 to 3 meters, such as from 1.5 to 2.5 meters.

In a still further embodiment, the second barrier element is selected from a solid physical element, such as a brick wall, a metal plate, a glass wall or plate. In another embodiment, the second barrier element is selected from a virtual element, such as a wind curtain. In a further embodiment, the second barrier element is selected from a bush, a tree, a shrubbery, or a planter box.

Typically, the second barrier will extend from a wall of a building and have a length that is sufficient to block the wind or at least partially block the wind or support the first barrier to create an optimal zone that can be cleaned according to the present invention.

In a further embodiment, the second barrier element has a length from 0.5 to 2 meters, such as from 1 to 1.5 meters, such as about 1.2 meters. In a further embodiment, the second barrier element has a height of from 1.5 to 3 meters, such as 1.5 to 2.5 meters.

In a further embodiment, the specified zone is in a street canyon. Typically, the specified zone is in a street canyon having a height to width ratio of at least 1, such as at least 2.

In a further embodiment, the air delivery system of the present invention comprises a control mechanism which is adapted to regulate cooling and clean air mass flow rate when a cleaned volume of the specified zone reaches a desired height and/or volume.

In a further embodiment, the air cleaning unit is capable of cleaning ambient air comprising exhaust gases, such as NOx and SOx, ultrafine particles, ozone, particulate matter, volatile organic compounds, urban pollutants, naturally occurring compounds, emissions from traffic, industrial sites (power plants, paint shops, sewage treatment plants, tunnels, air terminals, harbors, ferry terminals), construction sites, natural sources (fires, dust storms), occupational air pollution loads that include hazardous and non-hazardous concentrations of pollution, such as high H₂S concentrations, or high VOC concentrations.

In a further embodiment, the air cleaning unit comprises a gas phase advanced oxidation (GPAO). A preferred GPAO is described by Johnson and Arlemark in

WO2009138464A1 as well as in the paper by Johnson, Matthew S., Elna JK Nilsson, Erik A.

Svensson, and Sarka Langer. "Gas-phase advanced oxidation for effective, efficient in situ control of pollution." Environmental science & technology 48, no. 15 (2014): 8768-8776.

In another embodiment, the air cleaning unit comprises a filter, such as a filter selected from the group consisting of an active carbon filter, a gas adsorbing filter, an electrostatic filter, and a fabric filter.

In a further embodiment, the air cleaning unit comprises a GPAO and a means for driving air over the GPAO, wherein the GPAO is adapted to clean ambient air.

In a still further embodiment, the air cleaning unit and air cooling unit are located in one housing. The air cleaning unit and air cooling unit may also be located in separate housings, such as cabinets, as long as they are connected, for instance by a tube or similar, so that air can flow from one to the other.

In a further embodiment, the means for driving air over the filter is selected from a fan and wind power. Typically, the means for driving air over the filter is a fan. Typically, an embodiment for the means for driving air over the filter is selected from one or more of the group consisting of a fan, wind power, thermal convection, flow convection and solar power.

In a still further embodiment, the means for driving air over the GPAO is selected from a fan and wind power. Typically, the means for driving air over the GPAO is a fan.

In a further embodiment, the air cleaning unit and air cooling unit are located in separate housings, such as cabinets.

In a still further embodiment, the air cleaning unit and the air cooling unit are adapted to be mounted on a vertical wall.

In a further embodiment, the first barrier element is adapted to be mounted on a vertical wall.

In a still further embodiment the first and second barrier element are adapted to be mounted on a vertical wall.

In a still further embodiment, the air cleaning unit and the air cooling unit are adapted to be mounted on the first, the second or both of the barrier elements. In a second aspect, the present invention relates to an air delivery system for providing cleaned air to a specified zone, such as a street canyon, comprising a) an air cleaning unit having an inlet and an outlet, wherein the inlet is adapted to receive ambient air and the outlet is adapted to provide the cleaned air, and b) a first barrier element having a first side and a second side opposite each other, wherein the barrier element is adapted to block wind hitting the first side and create the specified zone on the second side with reduced or no wind, wherein the air cleaning unit is adapted to provide cleaned air in the specified zone.

The term "first barrier" is used here in the second aspect to indicate that there may be further barriers, but also indicates one barrier.

In an embodiment of the second aspect, the air delivery system comprises a barrier element that defines an enclosed area that is open to the ambient environment at its top, such as an open-top cylinder, or a circular or polygonal barrier, or a frustum on top of an open-top cylinder, which may have an angled or curved top, windows and doors or an opening in the wall for people to walk through, wherein the barrier element is adapted to prevent air from entering the area, and wherein the air cleaning unit is adapted to provide cleaned air in the specified zone.

The specified distance across the enclosed area, such as the diameter of the circular area or the distance across the polygonal area, can vary depending on the specified zone to be cleaned and the size of such area. For instance, the specified zone is an open or semi-open space, and the distance is from 5 to 20 meters. Typically, the specified distance is from 5 to 30 meters, such as from 10 to 20 meters, such as from 10 to 15 meters. In a further embodiment, the air delivery system comprises a second barrier element having a third side and a fourth side opposite each other, wherein the second barrier element is in a specified distance from the first barrier element, so that the specified zone is located between the second side of the first barrier element and the third side of the second barrier element.

The specified distance between the first and second barrier element in the second aspect can vary depending on the specified zone to be cleaned and the size of such area. For instance, the specified zone is a cafe or restaurant located in a street with tall buildings on each side of the street, and the distance is from 5 to 20 meters. Typically, the specified distance is from 5 to 30 meters, such as from 10 to 20 meters, such as from 10 to 15 meters. In a still further

embodiment, both the first and the second barrier elements are present.

In a still further embodiment, the first barrier element is selected from a solid physical element, such as a brick wall, a metal plate, a glass wall or plate. In another embodiment, the first barrier element is selected from a virtual element, such as a wind curtain.

In a further embodiment, the first barrier element has a length from 0.5 to 2 meters, such as from 1 to 1.5 meters, such as about 1.2 meters. In a further embodiment, the first barrier element has a height of from 1.5 to 3 meters, such as 1.5 to 2.5 meters.

In a still further embodiment, the second barrier element is selected from a solid physical element, such as a brick wall, a metal plate, a glass wall or plate. In another embodiment, the first barrier element is selected from a virtual element, such as a wind curtain.

In a further embodiment, the second barrier element has a length from 0.5 to 2 meters, such as from 1 to 1.5 meters, such as about 1.2 meters. In a further embodiment, the second barrier element has a height of from 1.5 to 3 meters.

In a still further embodiment, the specified zone is a street canyon, such as a street canyon having a height to width ratio of at least 1, such as at least 2.

In a further embodiment, the air cleaning unit is capable of cleaning ambient air comprising exhaust gases, such as NOx and SOx, ultrafme particles, ozone, particulate matter, volatile organic compounds, urban pollutants, naturally occurring compounds, emissions from traffic, industrial sites (power plants, paint shops, sewage treatment plants, tunnels, air terminals, harbors, ferry terminals), construction sites, natural sources (fires, dust storms), occupational air pollution loads that include hazardous and non-hazardous concentrations of pollution, such as high H₂S concentrations, or high VOC concentrations.

In a still further embodiment, the air cleaning unit comprises a gas phase advanced oxidation (GPAO). In another embodiment, the air cleaning unit comprises a filter, such as a filter selected from the group consisting of an active carbon filter, a gas adsorbing filter, an electrostatic filter, and a fabric filter.

In a further embodiment, the air cleaning unit comprises a filter and a means for driving air over the filter, wherein the filter is adapted to clean ambient air.

In a still further embodiment, the air cleaning unit comprises a GPAO and a means for driving air over the GPAO, wherein the GPAO is adapted to clean ambient air.

In a further embodiment, the means for driving air over the filter is selected from a fan and wind power. Typically, the means for driving air over the filter is a fan.

In a further embodiment, the air cleaning unit is located in a housing, such as a cabinet.

In a still further embodiment, the air cleaning unit is adapted to be mounted on a vertical wall.

In a still further embodiment, the air cleaning unit is adapted to be mounted the first barrier element. Alternative, the air cleaning unit is adapted to be mounted the second barrier element. The air cleaning unit may also be adapted to be mounted both or all barrier elements.

In a third aspect, the present invention relates to a method of providing cleaned air and optionally cleaned and cooled air to a specified zone, such as a street canyon, comprising leading ambient air into an air delivery system of the present invention.

In a further aspect, the present invention relates to a method of providing cleaned air and cooled air to a specified zone, comprising leading ambient air into an air cleaning system for providing cleaned and cooled air to the specified zone, the air delivery system comprising a) an air cleaning unit having an inlet and an outlet, wherein the inlet is adapted to receive ambient air or cooled air and the outlet is adapted to provide the cleaned and cooled air or the cleaned air, and b) an air cooling unit having an inlet and an outlet, wherein the inlet is adapted to receive ambient air or cleaned air and the outlet is adapted to provide the cleaned and cooled air or the cooled air, wherein the inlet of the cooling unit is connected to the outlet of the air cleaning unit, or wherein the outlet of the cooling unit is connected to the inlet of the air cleaning unit, thereby providing cleaned air and cooled air to the specified zone.

In a further embodiment, a specific temperature of the air outside the specified zone and before entering the air delivery system of the present invention is lowered by at least 2°C, such as at least 3 °C, when exiting the air cleaning unit to provide cleaned and cooled air to the specified zone. For instance, the air outside the specified zone, such as the incoming wind from the top of the buildings adjacent to the street canyon, is 25°C when lead into the system, according to the third or further aspect of the present invention, and the air cooling unit applies cooling sufficient to provide cleaned air and cooled air to the specified zone which is 22°C or lower, such as 20°C.

In a still further aspect, the present invention relates to a method of providing cleaned air to a specified zone, comprising leading ambient air into an air delivery system for providing cleaned air to the specified zone, the air delivery system comprising a) an air cleaning unit having an inlet and an outlet, wherein the inlet is adapted to receive ambient air and the outlet is adapted to provide the cleaned air, and b) a first barrier element having a first side and a second side opposite each other, wherein the barrier element is adapted to block wind hitting the first side and create the specified zone on the second side with reduced or no wind, wherein the air cleaning unit is adapted to provide cleaned air in the specified zone, thereby providing cleaned air to the specified zone.

Each and every embodiment as described in connection with the first and second aspects also applies to the third and further aspects described above, both individually and in combination.

The term "a housing" as used herein is a shield, such as a cabinet covering the air cleaning unit or the air cooling unit.

The term "a specified zone" as used herein means a zone of cleaned air surrounding the outlet of the air cleaning unit or system which can be adjusted according to the desired purpose. The outlet and speed of the cleaned air coming out can be adjusted to create a small zone or a larger zone of cleaned air, such as to provide cleaned air extending up to 2 m in different directions from the outlet of the air cleaning unit or system hereby creating the specified zone. The term "an air cleaning unit" as used herein means a unit that is configured to draw air into the unit wherein the air is cleaned from pollution, such as by leading the air through a filter removing the pollution or part of the pollution, and then is emitted out of the unit, for instance by means of a fan, wind power or similar means. Typical construction of such air cleaning units is known to the skilled person. The air cleaning unit is adapted to receive current from for instance a power cable.

The term "an air cooling unit" as used herein means a unit that is configured to draw air into the unit wherein the air is cooled, such as by leading the air through a cooling device, such as a refrigeration system, peltier element, or by using a water based system (e.g. water based chilled beam), and then is emitted out of the unit, for instance by means of a fan, wind power or similar means. Typical construction of such air cooling units is known to the skilled person. The air cooling unit is adapted to receive current from for instance a power cable.

As used herein the term "ultrafme particles" means particles smaller than 300 nm in mean mass aerodynamic diameter (MMAD). The term "nanoparticles" is used interchangeably with ultrafme particles.

As used herein the term "fine particles" means particles larger than 300 nm and smaller than 3 micrometers in MMAD.

Any one of the embodiments of the air cleaning device of the present invention specified above either alone or in combination constitute a separate embodiment of the personalized air cleaning device of the present invention.

The invention will now be described more fully with reference to the appended drawings illustrating typical embodiments of the street furniture with air cleaning devices integrated therein.

These drawings are by no means limiting the scope of the present invention and are only intended to guide the skilled person for better understanding of the present invention.

Figure 1 illustrates a street canyon (10) with an area (18) of polluted air. The street canyon is defined by tall buildings having walls (12, 16) facing the street canyon and a street (14) for cars and/or pedestrians. Mannequin (20) illustrates a human subject standing or walking in the street (14). An air cleaning device is indicated by (22).

Figure 2 illustrates the street canyon (10, 60) of figure 1 wherein an area of polluted air (68) is surrounded by buildings and street, wherein the area (68) is defined by walls (62, 66) and a street (64). Mannequin (70) illustrates a human subject standing or walking in the street (64). An air cleaning device is indicated by (72). Contour lines (74, 76, 78, 80, 82) illustrates the level of cleaned air provided by a standard air cleaning device (72) placed on a wall (62) of a building facing the street canyon. The line (82) indicates where there is 30% clean air, and as can be seen this area defined by line (82) is far from the breathing zone of the human (70), and here the quality of cleaned air near the human breathing zone is even lower than 30%. The arrows (84) shows the wind movement in the street canyon when the wind blows from above the buildings perpendicular to the direction of the street (64).

Figure 3 illustrates an air delivery system of the present invention (42, 44, 46) comprising a) an air cleaning unit (44) having an inlet (42) and an outlet (46), and b) an air cooling unit (44) having an inlet (42) and an outlet (46), wherein the inlet is adapted to receive ambient air or cleaned air and the outlet is adapted to provide the cleaned and cooled air or the cooled air. The air delivery system of the present invention is placed on a wall (32) of a building similar to what is illustrated in figures 1 and 2. Here the area of polluted air (38) is surrounded by buildings and the street, wherein the area (38) is defined by walls (32, 36) and a street (34). Mannequin (40) illustrates a human subject standing or walking in the street (34). The air delivery system is indicated by (42, 44, 46). Contour lines (50, 52, 54, 56, 58) illustrates the level of cleaned air provided by the air cleaning device (42, 44, 46) placed on a wall (32) of a building facing the street canyon (30). The line (58) indicates where there is 99% clean air, and as can be seen this area defined by line (58) is above the breathing zone of the human (40). The arrows (48) shows the wind movement in the street canyon when the wind blows from above the buildings perpendicular to the direction of the street (34).

Figure 4 illustrates the air delivery system of the present invention (102) as shown in figure 3. The air delivery system of the present invention is placed on a wall (92) of a building. Here the area of polluted air (98) is surrounded by buildings and the street, wherein the area (98) is defined by walls (92, 96) and a street (94). Mannequin (100) illustrates a human subject standing or walking in the street (94). The air delivery system is indicated by (102). Contour lines (106, 108, 110, 112, 114) illustrates the level of cleaned air provided by the air cleaning device (102) placed on a wall (92) of a building facing the street canyon (90). The line (114) indicates where there is 99% clean air, and as can be seen this area defined by line (114) is above the breathing zone of the human (100). The arrows (104) shows the wind movement in the street canyon when the wind blows from above the buildings (116, 118) perpendicular to the direction of the street (94) and moving from right (119) to left (117).

Figure 5 illustrates a street canyon (120) seen from the top-down, wherein the street (138) is defined by a first wall (130) of a building and a second wall (132) of a building. The wind carrying polluted air may blow from right to left or left to right, where ends (134, 136) are a cut-off the street (138) to fit it to this illustration. On the first wall (130) is mounted an air delivery system of the present invention, comprising a) an air cleaning unit (122, 124) having an inlet and an outlet, and b) barrier elements (126, 128). The barrier elements are adapted to block wind hitting the first side facing (134) and create the specified zone on the second side facing (136) or vice versa. The barrier elements (126, 128) are 1.2 m protruding into the street (138) but can have any length depending on the width of the street.

Figure 6 shows the results of tests carried out in the street canyon (140) shown in figure 5. Here the wind carrying polluted air blows from left (148) to right (158). On the first wall (130) is mounted an air delivery system of the present invention, comprising a) a first air cleaning unit (154) and a second air cleaning unit (156) having inlets and outlets, and b) a first barrier element (150) and a second barrier element (152). The barrier elements (150, 152) in these tests block wind coming from left to right. The black color (142) indicates completely polluted air and white color (144) indicates clean air. White lines (146) indicates streamlines of the air flow and describes how flow moves in the street canyon. As it can be seen in figure 6, incoming wind (148) brings pollution to the street (from left side), wherein the air delivery system (154, 156) and the first wall (150) completely separates polluted air and creates a big recirculation zone (144) in the area between the two walls (150, 152). Figure 7 illustrates an air delivery system of the present invention comprising a) an enclosed circular area with walls (184, 204) that is open to the ambient environment at its top and b) air cleaning units (186) mounted on the vertical walls. Figure 7 presents a cross-section view of the 3D geometry wherein the walls (184, 204) comprise a vertical part (184) and a sloping frustum (204) and have a total height of 3 m. The diameter of the enclosed circular area (202) surrounded by the walls (184,) is 10 m, wherein the height of the vertical wall component (184) is 2 m and the length of the frustum (204) is 1.774 m.

In the air delivery system depicted in Figure 7, five identical air cleaning units (186) are installed on the wall (184), each one of which has an inlet (190) to draw in polluted air and an outlet (188) to blow clean air. The centre of each air cleaning unit (186) is 0.5 m above the ground (182). Each air cleaning unit is designed to generate a clean air flow rate of 700 m³ h^"1 (3500 m³ h^"1 in total) while the wind speed at a height of 10 m above the ground is assumed to be 2.5 m s^"1. In an outdoor environment, polluted wind (indicated by arrows above the walls (184, 204)) passes above the structure (184, 186, 204) from left to right.

The vectors (200) and the contour lines (192-198) shown in Figure 7 present the experimental results; the vectors (200) present direction and a qualitative view of the air flow movement in the domain (202) while the contour lines (192-198) present air pollution levels in the system. The first contour line (192) illustrates the area where the air pollution level is 90%, the second contour line (194) illustrates the area where the clean air level is 80%, the third line (196) present 60% clean air area and the fourth line (198) presents 40% clean air level. As it can be seen in figure 7, most of the interior domain volume (202) has 90% or more cleaned air.

All references, including publications, patent applications and patents, cited herein are hereby incorporated by reference to the same extent as if each reference was individually and specifically indicated to be incorporated by reference and was set forth in its entirety herein.

All headings and sub-headings are used herein for convenience only and should not be construed as limiting the invention in any way.

Any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.

Recitation of ranges of values herein are merely intended to serve as a short method of referring individually to each separate value falling within the range, unless other- wise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. Unless otherwise stated, all exact values provided herein are representative of corresponding approximate values (e.g., all exact exemplary values provided with respect to a particular factor or measurement can be considered to also provide a corresponding approximate measurement, modified by "about", where appropriate).

All methods described herein can be performed in any suitable order unless other- wise indicated herein or otherwise clearly contradicted by context.

The terms "a" and "an" and "the" and similar referents as used in the context of describing the invention are to be construed to insert both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Thus, "a" and "an" and "the" may mean at least one, or one or more.

The term "and/or" as used herein means each individual alternative as well as the combined alternatives, for instance, "a first and/or second barrier" is intended to mean one barrier alone, the other barrier alone, or both the first and the second barrier at the same time.

The use of any and all examples, or exemplary language (e.g., "such as") provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise indicated. No language in the specification should be construed as indicating any element is essential to the practice of the invention unless as much is explicitly stated.

Throughout the description when "selected from" or "selected from the group consisting of is used it also means all possible combinations of the stated terms, as well as each individual term.

The citation and incorporation of patent documents herein is done for convenience only and does not reflect any view of the validity, patentability and/or enforceability of such patent documents.

The description herein of any aspect or embodiment of the invention using terms such as "comprising", "having", "including" or "containing" with reference to an element or elements is intended to provide support for a similar aspect or embodiment of the invention that "consists of, "consists essentially of, or "substantially comprises" that particular element or elements, unless otherwise stated or clearly contradicted by context (e.g., a composition described herein as comprising a particular element should be understood as also describing a composition consisting of that element, unless otherwise stated or clearly contradicted by context).

This invention includes all modifications and equivalents of the subject matter re-cited in the aspects or claims presented herein to the maximum extent permitted by applicable law.

The features disclosed in the foregoing description may, both separately and in any combination thereof, be material for realizing the invention in diverse forms thereof.

EXPERIMENTALS

The results presented in this document are obtained by carrying out Computational Fluid Dynamics (CFD) simulations. By using CFD simulation it is possible to understand and analyse flow behaviour everywhere in a computational domain. A 3D geometry of street canyon was modeled in order to find out effect of cooling on efficiency of providing clean air to people in open spaces. A cross section of the geometry can be seen in Figure 1 , where two buildings with walls (12, 16) are located on each side of a street (14) and an air cleaner (22) is installed on one of the walls (12). A mannequin (20) with height of 2m is standing in middle of street and illustrates a human subject. Wind was blown over the building roofs (shown in figure 4, 1 16; 1 18) from right (1 19) to the left (1 17) with velocity of 3 m/s.

The Air cleaner (22, 102) width was 0.4 m, its length was 1.5m and height was lm. Then area of its outlet and inlet was equal to 0.6 m². Velocity of clean air set to be equal to 0.5 m/s in both inlet and outlet which made a flow rate of 0.3 m³/s (1080m³/h).

The air cleaner in this study was installed in height of 2m (it is working for other heights as well).

The modeled street (94) had a width of 8m and height of 25m (92, 96). In the modeling, a depth of 5m of street was modeled to study 3D effects of flow behavior. Symmetry boundary condition was applied on both inner and outer boundaries of the slice.

In this simulation, Navier-stokes equations were solved as well as energy equation in order to model flow behavior. K-epsilon RANS turbulence model was applied to simulate turbulence behavior of this compressible flow. Temperature of incoming wind was set to be 20 °C (the temperature of the mannequin was set to 30 °C, however, other temperatures were tested without any considerable changes in the result).

In simulation of cases when air cleaner cools the air a constant temperature was applied on the flow leaving air cleaner (46). Density of air was a function of temperature of air and both energy and turbulent flow equations were solved in two-way coupled method.

The air pollution distribution was modeled as a dispersed phase which moves along with the continuous phase. In regard of convection, one way coupled was considered. Diffusion coefficient of carbon dioxide in air was used (2.5* 10-5 m²/s) to simulate diffusion of pollution in air. Diffusion was found to have negligible impact on pollution distribution in the system in comparison with convection. In this simulation, incoming wind was assumed to be 100% polluted by lmol/m³. (This means 1 mole of pollution enters the zone along with lm3 of incoming air.) (which can have any concentration as long as it is considered as a dispersed phase method which is a method applicable for all of the urban air pollution cases, because the pollution cannot have effect on airflow pattern) and air cleaner exhaust flow is assumed to be completely clean.

Gravity has been considered in these simulations and all of the presented results are steady state results.

Results before cooling

A normal case of cleaning air without cooling was simulated firstly. Its result can be seen in Figure 2. Vectors/arrows (84) in this picture show direction of air flow and contours (74,76,78,80,82) show air cleanness level. As it can be seen, wind is blowing all the way down to the lower level of street canyon (68) where the air cleaner (72) is providing cleaned air and mixes this cleaned air with its polluted air and brings it up to the upper section of street canyon to finally leave the street canyon. In figure 2, contour line of (74) show 99% cleaned air, (76) indicates 90%> cleaned air, (78) indicates 70%>, (80) indicates 60%> and (82) indicates 30%>. Level of air pollution near to the breathing zone of the human (70) for this case is less than 30%.

Results after cooling for 5 degrees

In the next simulation, an air cooler is added to the air cleaner (102, 44) which sets constant temperature of 15 °C for the clean air which is leaving exhaust/outlet (46) of air cleaner (44, 102). This degree is 5 °C cooler than incoming wind (119) into system which is 20 °C warm. Figure 3 and figure 4 show results of this case. Figure 4 shows the result in the whole street canyon (98) and figure 3 presents same result in the lower part of street canyon (38). As it can be seen in Figure 4, the cooled clean air accumulates in the bottom of the street canyon and separates from incoming wind that can be clearly seen by the contour lines (50, 52, 54, 56, 58). Contour line (50) indicates locations with 30% clean air and 70% polluted air, line (52) indicates 50% clean air, line (54) indicates 70%> clean air, line (56) indicates 90%> clean air and line (58) indicates about 99% cleaned air. This means that air near to the breathing zone of the human (40) is about 100% cleaned. It means that people are breathing about 100% of the cleaned air coming from air cleaner.

Flow vectors (104) show that cooled and cleaned air is separated from the polluted wind which is blowing all the way down to the street. Density of cleaned air at human breathing zone gets about 1.7% higher than the polluted wind due to cooling. The wind vectors recirculate in the street (38, 98) from top to the border of clean air region (between line 50 and 58, and between lines 106 and 114). There are movements of clean air near to the human subject in the clean air region which are caused by the air cleaner unit.

Height of border of separation of clean and polluted air in this case is about 3 m, which assures delivery of clean air to the pedestrian (40).

This volume of dense and cleaned air near to the earth/street (34) assures that hot polluted exhaustion of cars will leave toward up efficiently and does not harm pedestrian (40). A control mechanism can be defined for the device (44, 102) in order to increase its efficiency. This control mechanism can turn off the device after reaching to a steady state and creating a clean zone bubble. The control mechanism can turn on the device again when the clean zone bubble is disappearing.

A temperature difference of 5 °C and air cleaner velocity of 0.5 m/s were studied in the previous simulation corresponding to figures 1-4. We have investigated different cases in regard of these two parameters and it turns out it is possible to provide the same amount of cleaned air for pedestrian in a more efficient way.

Simulation Figure 5 & 6

In these simulations 2D geometry of figure 5 was created where it contains a top view of the street (138) with a length of 40m (from 134 to 136) and a width of 8m (from 130 to 132). Two walls (126, 128) with length of 1.2m were installed in the middle of the street and there was a 10m distance between first wall (126) and second wall (128). Two air cleaner units (122, 124) were inserted between the two walls (126, 128) with lm distance to each wall. Outlet length of each air cleaner was 20 cm.

In these simulations air flow behavior was modeled by solving Navier-stokes equations and pollution was modeled by solving diffusion and convection of diluted species in air, which had same settings as the previous section. Temperature and energy was neglected here.

Polluted wind was blown from left side (134) with velocity of 1 m/s (flow rate of 8m³/s) and was leaving from right side (136). Each air cleaner (122, 124) was blowing cleaned air with a velocity of 0.5m s (flow rate of 0.2m³/s by both of them).

Flow rate of the air cleaner is assumed to be about 1/40 of wind (polluted air) passing through the street (138).

Figure 6 shows air pollution level in the domain shown in figure 5. Black color (142) indicates completely polluted air and white color (144) indicates clean air. White lines (146) show streamlines of the flow and describes how flow moves in the domain. As it can be seen in figure 6, incoming wind (148) brings pollution to the street (from left side), and the first wall (150) completely separates polluted air and creates a big recirculation zone (144) in the area between the two walls (150, 152). Air cleaners (154, 156) clean air in this area which works effectively in the recirculation zone due to a higher age of air in this area (flow stays longer in this area). Second wall (152) will act in the same way as first wall (150) when wind is blowing from right to left.

Simulation Figure 7

In these simulations, a 3D geometry of an enclosed circular area that is open to the ambient environment at its top was created comprising walls (184, 204) and air cleaning units (186). Figure 7 presents a cross-section view of the 3D geometry wherein the walls comprise a vertical part (184) and a sloping frustum (204) and have a total height of 3 m. The diameter of the enclosed circular area surrounded by the walls (202) is 10 m, wherein the height of the vertical wall component (184) is 2 m and the length of the frustum is 1.774 m.

Five identical air cleaning units (186) are installed on the walls, each one of which has an inlet (190) to draw in polluted air and an outlet (188) to blow clean air. The centre of each air cleaning unit (186) is 0.5 m above the ground (182). Each air cleaning unit is designed to generate a clean air flow rate of 700 m³ h^"1 (3500 m³ h^"1 in total) while the wind speed at a height of 10 m above the ground is assumed to be 2.5 m s^"1. In an outdoor environment, polluted wind passes above the structure (180) from left to right. The CFD modelling setup for these simulations is the same as the simulations for figures 5 and 6.

The vectors (200) and the contour lines (192-198) shown in Figure 7 present the experimental results; the vectors (200) present direction and a qualitative view of the air flow movement in the domain while the contour lines (192-198) present air pollution levels in the system. The first contour line (192) illustrates the area where the air pollution level is 90%, the second contour line (194) illustrates the area where the clean air level is 80%, the third line (196) present 60% clean air area and the fourth line (198) presents 40% clean air level. As it can be seen in figure 7, most of the interior domain volume (202) has 90% or more cleaned air.

Claims

We claim:

1. An air delivery system for providing cleaned and cooled air to a specified zone, such as a street canyon, comprising a) an air cleaning unit having an inlet and an outlet, wherein the inlet is adapted to receive ambient air or cooled air and the outlet is adapted to provide the cleaned and cooled air or the cleaned air, and b) an air cooling unit having an inlet and an outlet, wherein the inlet is adapted to receive ambient air or cleaned air and the outlet is adapted to provide the cleaned and cooled air or the cooled air, wherein the inlet of the cooling unit is connected to the outlet of the air cleaning unit, or wherein the outlet of the cooling unit is connected to the inlet of the air cleaning unit; or c) a unit for cleaning and cooling air simultaneously, having an inlet and an outlet, wherein the inlet is adapted to receive ambient air and the outlet is adapted to provide the cleaned and cooled air.

2. The air delivery system of claim 1 comprising a first barrier element having a first side and a second side opposite each other, wherein the barrier element is adapted to block wind hitting the first side and create the specified zone on the second side with reduced or no wind, wherein the air delivery system is adapted to provide cleaned and cooled air in the specified zone.

3. The air delivery system of claim 2 wherein the first barrier element defines an enclosed area that is open to the ambient environment at its top, which may have an angled or curved top, optionally windows and doors or an opening in the wall for people to walk through, wherein the barrier element is adapted to prevent air from entering the area, and wherein the air cleaning unit is adapted to provide cleaned and cooled air in the specified zone.

4. The air delivery system of claim 2 comprising a second barrier element having a third side and a fourth side opposite each other, wherein the second barrier element is in a specified distance from the first barrier element, so that the specified zone is located between the second side of the first barrier element and the third side of the second barrier element.

5. The air delivery system of any one of claims 1-4 wherein the specified zone is a zone for people to reside and is selected from an open space, such as a street, stadium, urban area, park, or an area that people gather for big ceremonies, events and parties in open spaces; or a semi-open space, such as a train station, malls, transportation stations and terminals including trains, buses and airplanes, industrial hall, temple (church, mosque, etc.), airport, conference center, museum, exhibition, lecture hall.

6. The air delivery system of any one of claims 2-5 wherein the first and/or second barrier element is selected from a solid physical element, such as a brick wall, a metal plate, a glass wall or plate, or a more virtual element, such as a wind curtain.

7. The air delivery system of claim 5 or 6 wherein the specified zone is in a street canyon, such as in a street canyon having a height to width ratio of at least 2.

8. The air delivery system of any one of claims 1-7 wherein the air cleaning unit comprises a filter and a means for driving air over the filter, wherein the filter is adapted to clean ambient air.

9. The air delivery system of any one of claims 1-8 wherein the air cleaning unit is capable of cleaning ambient air comprising exhaust gases, such as NOx and SOx, ultrafine particles, ozone, particulate matter, volatile organic compounds, urban pollutants, naturally occurring compounds, emissions from traffic, industrial sites (power plants, paint shops, sewage treatment plants, tunnels, air terminals, harbors, ferry terminals), construction sites, natural sources (fires, dust storms), occupational air pollution loads that include hazardous and non-hazardous concentrations of pollution, such as high H₂S concentrations, or high VOC concentrations.

10. The air delivery system of any one of claims 1-9 wherein the means for driving air over the filter is selected from one or more of the group consisting of a fan, wind power, thermal convection, flow convection and solar power.

11. The air delivery system of any one of claims 1-10 wherein the air cleaning unit comprises a gas phase advanced oxidation (GPAO) or a filter, such as a filter selected from the group consisting of an active carbon filter, a gas adsorbing filter, an electrostatic filter, and a fabric filter.

12. The air delivery system of any one of claims 1-11 wherein the air cleaning unit and air cooling unit are located in one housing.

13. The air delivery system of any one of claims 1-11 wherein the air cleaning unit and air cooling unit are located in separate housings.

14. The air delivery system of any one of claims 1-13 wherein the air cleaning unit and the air cooling unit are adapted to be mounted on a vertical wall, and optionally the first and/or second barrier element is adapted to be mounted on a vertical wall.

15. The air delivery system of any one of claims 1-13 wherein the air cleaning unit and the air cooling unit are adapted to be mounted on barrier elements.

16. The air delivery system of any one of claims 1-15 wherein multiple air cleaning and/or cooling units are supplying air in the specified zone, and wherein these units may be oriented either to blow air into the specified zone, to recirculate air within the zone, or some combination of the two.

17. An air delivery system for providing cleaned air to a specified zone, such as a street canyon, comprising a) an air cleaning unit having an inlet and an outlet, wherein the inlet is adapted to receive ambient air and the outlet is adapted to provide the cleaned air, and b) a first barrier element having a first side and a second side opposite each other, wherein the barrier element is adapted to block wind hitting the first side and create the specified zone on the second side with reduced or no wind, wherein the air cleaning unit is adapted to provide cleaned air in the specified zone.

18. The air delivery system of claim 17 wherein the first barrier element defines an enclosed area (specified zone) that is open to the ambient environment at its top, which may have an angled or curved top, optionally windows and doors or an opening in the wall for people to walk through, wherein the barrier element is adapted to prevent air from entering the area, and wherein the air cleaning unit is adapted to provide cleaned air in the specified zone.

19. The air delivery system of claim 17 comprising a second barrier element having a third side and a fourth side opposite each other, wherein the second barrier element is in a specified distance from the first barrier element, so that the specified zone is located between the second side of the first barrier element and the third side of the second barrier element.

20. The air delivery system of any one of claims 17-19 wherein the specified zone is a zone for people to reside and is selected from an open space, such as a street, stadium, urban area, or park, or a semi-open space, such as a train station, malls, industrial hall, temple (church, mosque, etc.), airport, conference center, museum, exhibition, lecture hall.

21. The air delivery system of any one of claims 17-20 wherein the first and/or second barrier element is selected from a solid physical element, such as a brick wall, a metal plate, a glass wall or plate, or a more virtual element, such as a wind curtain.

22. The air delivery system of any one of claims 17-21 wherein the specified zone is in a street canyon, such as in a street canyon having a height to width ratio of at least 1.

23. The air delivery system of any one of claims 17-22 wherein the air cleaning unit comprises a filter and a means for driving air over the filter, wherein the filter is adapted to clean ambient air.

24. The air delivery system of any one of claims 17-23 wherein the air cleaning unit is capable of cleaning ambient air comprising exhaust gases, such as NOx and SOx, ultrafme particles, ozone, particulate matter, volatile organic compounds, urban pollutants, naturally occurring compounds, emissions from traffic, industrial sites (power plants, paint shops, sewage treatment plants, tunnels, air terminals, harbors, ferry terminals), construction sites, natural sources (fires, dust storms), occupational air pollution loads that include hazardous and non-hazardous concentrations of pollution, such as high H₂S concentrations, or high VOC concentrations.

25. The air delivery system of any one of claims 17-24 wherein the means for driving air over the filter is selected from one or more of the group consisting of a fan, wind power, thermal convection, flow convection and solar power.

26. The air delivery system of any one of claims 17-25 wherein the air cleaning unit comprises a gas phase advanced oxidation (GPAO) or a filter, such as a filter selected from the group consisting of an active carbon filter, a gas adsorbing filter, an electrostatic filter, and a fabric filter.

27. The air delivery system of any one of claims 17-26 wherein the air cleaning unit is located in a housing.

28. The air delivery system of any one of claims 17-27 wherein the air cleaning unit is adapted to be mounted on a vertical wall, and the first and/or second barrier element is adapted to be mounted on a vertical wall.

29. The air delivery system of any one of claims 17-28 comprising an air cooling unit having an inlet and an outlet, wherein the inlet is adapted to receive ambient air or cleaned air and the outlet is adapted to provide the cleaned and cooled air or the cooled air.

30. The air delivery system of claim 29 wherein the air cleaning unit and the air cooling unit are adapted to be mounted on the first, the second or both barrier elements.

31. The air delivery system of any one of claims 29-30 wherein multiple air cleaning and cooling units are supplying air in the specified zone, and wherein these units may be oriented either to blow air into the specified zone, to recirculate air within the zone, or some combination of the two.

32. A method of providing cleaned air and optionally cleaned and cooled air to a specified zone, such as a street canyon, comprising leading ambient air into an air cleaning system of any one of claims 1-31.

33. The method of claim 32 wherein a temperature of the air outside the specified zone and before entering the air cleaning system of any one of claims 1-16 is lowered by at least 2°C when exiting the air cleaning unit to provide cleaned and cooled air to the specified zone.