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Cigarette and air pollution

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Par   •  12 Février 2023  •  Étude de cas  •  2 050 Mots (9 Pages)  •  266 Vues

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Air pollution

Cigarette smoke

Claire GABRIEL | Cleaning techniques | 12/11/2022


Table of Contents

Introduction        2

Background        2

Cleaning technique        4

Air ionization theory        4

Process Scheme        6

Limits        7

Conclusion        7

References        7


Introduction

Atmospheric properties can be changed by  pollutants in the atmosphere which manifest as smoke or temperature modification, odors etc. These pollutants can be either gas or particles. Air pollution is a growing concern as it touches practically all countries in the world and all parts of society. As a consequence, air pollution,  ambient (outdoor) just as household (indoor) is the most consequent environmental risk to health . Because everyone breathes thousands of gallons of air each day, we are  constantly exposed to this form of pollution. In 2012 the World Health organization (WHO) reported that air pollution was responsible for about one in every nine deaths. The six main ambient air pollutants which are similar for household and ambient air pollution, are particulate matter, ground-level ozone, lead, carbon monoxide, nitrogen oxides and sulfur dioxide.

Each year, smoking releases approximately 5.2 billion kilograms of methane and 2.6 billion kilograms of CO2 into the environment, all of which smoking contributes to this air pollution. Although carbon dioxide and methane are not responsible for the development of health risks and death in smokers, they do contribute to air pollution. Furthermore,  one source of fine particulate matter is tabaco smoking which is divided into mainstream smoke (smoke directly inhaled by the smoker) and side stream smoke encompassing the smoke coming off the sides of the burning tobacco product plus smoke exhaled by the smoker (commonly known as second-hand smoke). As a result, the air pollution emitted by cigarettes is 10 times greater than diesel car.

Because smoking is often done in closed environment, exposing non-smokers to the smoke technologies such as Air Ionization should be developed in order to frame the health impact of smoking.

Background

Increases in smoking, urbanization, and the persistence of burning unrefined fuel indoors in low-and middle-income countries (more than 80% of the world’s population) have led to a substantial increase in exposure to environmental pollutants. Cigarettes butts are well known for their pollution, but the smoke also pollute the air. Cigarette smoke is the main source of indoor air pollution and is really dangerous for the health of people breathing it. Tobacco smoke is recognized to be a substantial source of oxidants and contains thousands of compounds, both in the particulate matter (PMx) and gas phases. Carbon monoxide, polycyclic aromatic hydrocarbons, tobacco-specific nitrosamines, nitrogen oxides, aldehydes, volatile organic compounds, nicotine, fine particulate matter, and oxidants are all present in both mainstream and side stream smoke. Although the toxicants and carcinogens present in both mainstream and side stream smoke are similar, their concentrations vary, usually as a result of different combustion temperatures. Gases, including the carcinogens vinyl chloride, formaldehyde, and N-nitrosodimethylamine, make up around 90% of cigarette smoke. The remaining 10% of smoke is made up of solid particles, including tar and nicotine, yet it is classified as one of the 98 hazardous smoke components that are damaging to health.

[pic 1] [pic 2]

Secondhand smoking can cause a lot of health damages at evert scale of human organism from the different organs to inside the cells reaching DNA and mitochondria . Passive smoking is the fact of inhaling, involuntarily, the smoke emitted by one or more smokers.  The French National Academy of Medicine estimates that in France, passive smoking kills about 3,000 non-smokers each year. According to the results of an American study conducted by researchers at the University of Aberdeen and published in 2014 in the journal Tobacco Control2, sharing one's home with a smoker would be as harmful to the lungs as living in a highly polluted city. Beyond the immediate irritation of the eyes, nose and throat, passive smoking can cause or worsen many respiratory diseases (infections, asthma disease, chronic obstructive pulmonary disease...). But that's not all, your neighbor's cigarette also increases your risk of lung cancer and coronary heart disease.6 American researchers have also found a link between active and passive smoking and the development of insulin resistance, considered a pre-diabetes condition. In addition, passive smoking alters artery walls and doubles the risk of stroke.

Cleaning technique

Air pollution of cigarettes mainly comes from the particulates and the odors. There are several existing techniques to remove them indoors. Various air-cleaning devices are used, for instance ,electrostatic precipitators, electret fiber filters, ionizers, activated carbon, impregnated alumina, ionizing lamps, and an electron generator.

In a study about the effectiveness of room air cleaner “Tobacco smoke removal with room air cleaners” lead by Lars Olander, Johan Johansson, Rolf Johansson , they concluded that at equivalent airflow rate, the clean airflow rate causes the same decay rate for contaminant concentrations in a room. They measured the rate of ozone emission by electrostatic precipitators and ionizers and another conclusion was that it is much mor difficult to remove gases than particles.

The technical focus will be in the air ionizer. It is an emergent technique which can remove significantly airborne microbials, neutralize odors and specific volatile organic compounds (VOC) in the indoor air environment as well as based on the ionization of the air. It also enhances HEPA filters removing very fine particulates (PMx).

In fact, ionization is increasingly being used inside clean rooms as more engineers realize that air filtration alone does not ensure the elimination of particulate contamination from subvisible particles (less than 25 microns).

[pic 3]

Air ionization theory

In overall, air ionization is a controlled process involving the electronically induced formation of small air ions, such as superoxide O2 , the diatomic oxygen radical anion, which react rapidly with airborne VOC and PMx species.

Ionization is a process that can occur naturally as in electromagnetic radiation (e.g., cosmic rays, gamma rays, lightning, and solar ultraviolet radiation) and alpha/gamma radiation from radioactive materials in the earth's crust. Air ionization systems work by sending a flow of positive and negative ions of anion and cation into the ambient air. An electrostatic charge is created due to the accumulation of ions on a non-conductive surface until an equilibrium state is reached by neutralization .Knowing that gas molecules are electrically neutral in air, the minimum energy required to ionize the molecules and atoms in the gas phase is called the first ionization energy (IE) . If this ionization energy is sufficient, then, one or more bound electrons are stripped from the molecule (or atom) and pass into the atmosphere as free electrons to give positively charged molecules. These primary positive ion species can undergo sequential ion-molecule reactions ion molecules with polar neutral water molecules to give protonates (for example, Hþ(H2O)4, m/z 73). Natural and anthropogenic pathways of ion formation Excited air molecules (N2 *and O*), generated during the ionization process can propagate O3 by chain reaction with NOx products. O3 is a strong oxidizing reagent, which provides a This provides a favorable environment for the destruction of VOCs, even at room temperature.

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