WASTE GAS

Okey this time I will post about the material science subjects namely Waste Gas. Did you ever hear the word waste gas? Perhaps there who've heard it but maybe some have not. For more details, let us refer to the explanation ..

 Air pollution can be caused by natural sources or as a result of human activity. In general contamination caused oleb natural source known magnitude is difficult, however we may still estimate the amount of air pollutants and activities. Air pollutants as a result of human activity, it is generally much more predictable, especially if unknown material type, material specifications, the ongoing process of the event, as well as the specifications of the unit operations used in the process and post-process. Besides the distribution of pollutants into the atmosphere can also be estimated with a variety of approaches. How to estimate the amount of pollutants coming out of a particular operating system, as well as the approach used to predict the distribution of these pollutants into the atmosphere will be described in the following discussion.Process Air PollutionAll chemical species are included or entry into the atmosphere of a "clean" called contaminants. Contaminants at concentrations high enough to cause a negative effect on the receiver (receptor), when this happens, disebat contaminant contaminant (pollutant).Diklasifihasikan air contaminants into 2 categories according to how contaminants enter or put into the atmosphere, namely: primary contamination and secondary contamination. Contamination is the primary contaminant emitted directly from the source of contamination. Secondary contaminants are contaminants that are formed by chemical processes in the atmosphere.Sources of contamination from human activity (anthropogenic) is any motor vehicle, facility, plant, installation or activity that emits primary air contaminants to the atmosphere. There are 2 categories of anthropogenic sources, namely: fixed sources (stationery source) such as: electricity generation with fossil fuels, factories, households, services, etc. and other (mobile source) such as trucks, buses, airplanes, and train.Five primary contaminant in total contributed over 90% of global air pollution are:a. Carbon monoxide (CO),b. Nitrogen oxides (NOx),c. Hydrocarbons (HC),d. Sulfur oxides (SOx)e. Particulates.In addition there is a primary contaminant secondary contamination is contamination that secondary impacts on environmental components or contaminants emitted from the primary contaminant transformation into a different form of contamination. There are several secondary contamination that can lead to significant impacts both locally, regionally and globally, namely:

a. CO2 (carbon monoxide),

b. Contamination smog (smoke fog) or smog (smoke fog),

c. Acid rain,

d. CFC (Chloro-Fluoro-Carbon/Freon),

e. CH4 (methane).

Elements of Air Pollutantsa :

a.Carbon monoxide (CO)Carbon monoxide pollution comes from natural sources such as forest fires, oxidation of terpenes emitted to the atmosphere of the forest, the production of CO by vegetation and marine life. Other sources of CO from anthropogenic sources, namely the burning of fossil fuels contributes 78.5% of the total emissions. Pollution from anthropogenic sources 55.3% comes from burning gasoline in automotive.

b. Nitrogen oxides (NOx)Important nitrogen oxide contamination from anthropogenic sources, namely: NO and NO2. Contribution of anthropogenic sources to total emissions of ± 10.6%.

c. Sulfur oxides (SOX)Sulfur compounds in the atmosphere consists of H2S, mercaptans, SO2, SO3, H2SO4salts of sulfite, sulfate salts, and organic sulfur aerosols. Of contamination is the most important thing is that SO2 contribute ± 50% of the total emissions. Sulphate and sulphite salt contamination in the form of aerosols from sea spray contributes 15% of total emissions.

d. Hydrocarbons (HC)The most important hydrocarbon contamination is CH4 (methane) + 860 / of the total hydrocarbon emissions, which are derived from 11% rice, 34% of the swamps, tropical forests 36%, mining and others 5%. Other hydrocarbon contamination is quite important is the terpene emissions (a-pinene p-pinene, myrcene, d-Iimonene) ± 9.2% of the plant total hydrocarbon emissions. Donations hydrocarbon emissions from sources antrofogenik 5% smaller than those derived from the burning of gasoline 1.8%, and evaporation of the solvent insineratc 1.9%.

e. ParticulateParticulate contaminants include particles of molecular size s / d> 10 μm.Particle size> 10 μm to be deposited by gravity from the atmosphere, and the smaller size of 0.1 μm generally do not cause environmental problems. It is therefore important particulate contamination is the size range from 0.1 to 10 μm. The main source of fuel combustion particulates are ± 13% - 59% and incineration.

f. Carbon dioxide (CO2)Contamination of CO2 emissions from fuel combustion and natural sources. The main anthropogenic source of contamination is the combustion of coal 52%, natural gas 8.5%, and 2.8% of forest firesg. Methane (CH4)Methane gas is a contaminant which, together with CO2, CFCs, and N2O causes the greenhouse effect that causes global warming. CH4 source of contamination is the rice (11%), marshes (34%), tropical forests (36%), mining, etc. (5%). The greenhouse effect can be understood from Figure 30. Sunlight entering the atmosphere about 51% is absorbed by the Earth's surface and partially transmitted and reflected radiation in the form of short wavelengths (30%) and partly in the form of infrared radiation (70%). Infrared radiation emitted by Earth's surface muffled by clouds. Gases CH4, CFCs, N2O, CO2 in the atmosphere resulting in pent-infrared radiation will increase which in turn will lead to global warming.

h. Photochemical smokescreenThe smoke haze is the result contamination photochemical reaction between O3, hydrocarbons and NOx to form a new compound aldehyde (RHCO) and Acil Peroxy Nitrate (PAN) (RCNO5).

i. Acid rainWhen the concentration of NOx and SOx contamination high in the atmosphere, it will be converted into HNO3 and H2SO4.The presence of hydrocarbons, NO2, metal oxides Mn (II), Fe (II), Ni (II), and Cu (II) accelerates the reaction of SO2 into H2SO4.HNO3 and H2SO4 together with HCI HCI emissions cause the degree of acidity (pH) of rain is low <>Ambient Air PollutionAmbient air quality is an early stage to understand the negative impact of air contaminants to the environment. Ambient air quality is determined by:

(1) the quantity of contaminant emissions from contamination sources,

(2) the transportation, conversion and removal of contaminants in the atmosphere.Ambient air quality will determine the negative effects of air contamination on public health and welfare (plants, animals, materials and other mark-Iain)Information on the health effects of air pollution exposure on the data derived from animal, epidemiological studies, and in the case of a limited study of exposure in humans. Research is continuously carried out with the aim of:

(1) Establish better concentration where the negative effects can be detected,

(2) determine the correlation between human and animal responses to contamination,

(3) Obtain more information on the epidemiology and

(4) Bridging the information gap and reduce uncertainty standards presently applied.Ambient air quality standard / ambient set for the contamination are: O3 (ozone), CO (carbon monoxide), NOx (nitrogen oxides), SO2 (sulfur oxides), non-methane hydrocarbons, and particulates. Air Quality National Quality Standard American (Table 13) that have been reviewed by the National Academics of Science and Environmental Protection Agency (NEPA) establishes standards of primary and secondary standards.Primary quality standard established to protect the safety margin is sufficient (adequate margin of safety) public health which are set to protect the most people (15-20%) were susceptible to air pollution. Secondary quality standard set to protect public welfare (materials, plants, animals) of any negative effects of air pollution are known or can be anticipated.Based on ambient air quality standard specified emission standards based on the anticipation that the contaminant emissions under the standards and the process of transportation, conversion, and removal of contaminants, the quality will not exceed the ambient air quality standard. One example is the emission standards for Steam Power Plants with Fuel Coal.Emission factorIf a certain amount of fuel burned, it will come out a certain amount of combustion gases. For instance, coal generally. Its chemical formula is written in the C (carbon), when burned perfectly with 02 (oxygen) will produce CO2 (carbon dioxide). But in fact it is not.It turned out to any coal burned also produced other products besides CO2, which is CO2 (carbon monoxide), HCHO (aldehyde), CH4 (methane), NO2 (nitrogen dioxide), SO2 (sulfur dioxide) and Abu.Products of combustion than CO2, commonly referred to as a pollutant (contaminant).Emission factor is here defined as a certain weight of pollutants generated by burning a fuel se / ama certain period of time. From this definition it can be seen that if something pollutant emission factors are known, then the amount of pollutants that pass from the combustion process can be determined amount per time unit.Distribution of pollutantPollutants emitted from the system will spread into the atmosphere.The concentration of pollutants in the air as a result of the distribution of pollutant emission sources can be estimated with a variety of approaches, such as the model of a black box (black box model), the normal Gaussian distribution model (Gaussian model), and other models.Plume rise (smoke rising)Upward movement of clouds of gas from a height of chimney (stack), until the smoke flowing horizontally is known as the "plume rise" or rising smoke. The increase is due to the momentum due to the vertical velocity and the gas temperature difference "flue gas" with ambient air. Because of this plume rise, stack height are physically unable to use the Gauss equation.Instead, stack height needs to be supplemented with high rise smoke that is known the effective stack height.Correlation Between Air Pollution and HealthAir pollution can cause health problems in humans in many ways, such as by a factor stimulates or triggers a number of diseases. Groups affected especially infants, the elderly and low-income groups who usually live in big cities with housing conditions and poor environmental. Examine the correlation between air pollution and health, is quite difficult. This is because:

1. The amount and type of contaminants are manifold.

2. The difficulty in detecting contaminants that can pose a danger to the very low concentrations.

3. Synergistic interaction between the pollutant.

4. The difficulty in isolating a single factor that caused, because humans are exposed to a lot of substances harmful contaminants for a period that is long enough.

5. Illness and death records are incomplete and unreliable.

6. The cause of multiple and long incubation period of penyakitpenyakit (eg, emphysema, chronic bronchitis, cancer, heart disease).

7. Problems in extrapolating the results of laboratory experiments to the human animal.There is a strong correlation between air pollution with chronic bronchitis (chronic). Although smoking is almost always the highest order as a cause of chronic respiratory disease but the sulfur oxides, sulfuric acid, particulate matter, and nitrogen dioxide has been demonstrated as a cause and originators brochiale asthma, chronic bronchitis and pulmonary emphysema.The results of research in the United States sometime in the 70's showed that chronic bronchitis affects 1 in 5 people among American men aged between 40-60 years and the condition is associated with smoking and living in urban areas where the air is polluted.The actual relationship between air pollution and health or the onset of the disease it causes in fact still can not be explained clearly very well and is a very complex problem. Many other factors that will determine this causal relationship. However, statistical and epidemiological data from this relationship can be seen with the real.In general morbidity of data can be considered more important and useful than data on mortality. Moreover, the findings of physiological abnormalities in human life that occurred before the early signs of the disease can be seen or felt, as a result of air pollution, clear more important meaning. Precautions should already be implemented at the earliest possible time.WHO Inter Regional Symposium on Criteria for Air Quality and Method of Measurement has established several concentration levels of air pollution in relation to the consequences for the health / environment as follows:

Level I: Concentration and time exposed where not found any result, either directly or indirectly.

Level II: Concentration in which may be found on sensory irritation, harmful effect on plants, limiting vision or other consequences adverse to the environment (adverse level).

Level III: Concentration where obstacles may arise in physiological functions were vital as well as changes that may cause chronic disease or shortening of life (serious level).

Level IV: Concentration where possible acute illness or death in the sensitive population groups (emergency level).Some ways to calculate / check the effect of air pollution on health are among other records: the number of absences jobs / services, the number of certificate / medical certificate, the number of treatments in the hospital, the number of morbidity in children, the amount of morbidity in elderly people , the number of troops investigation anggotaanggota morbidity in patients with certain diseases such as heart disease, lung and so on.Investigations should be done prospectively and the comparative between areas with severe air pollution and light, by also taking into account other factors that might affect (eg air, eating habits, smoking, data meteorological, etc.).Diseases caused by air pollutionDiseases that can be caused by air pollution are:

1) Bronchitis chronica. The effect on women and men the same. This proves that the prevalence is not affected by the kinds of day-to-day work. By cleaning the air can decrease 40% of the mortality rate.

2) Emphysema Pulmonum.

3) bronchopneumonia.

4) Asthma bronchiale.

5) Cor pulmonale kronikum.In an industrial area in the Czech Republic for example, can be found a high prevalence of this disease. Similarly, in northern India where people live in clay houses without windows and using fire wood for home heating.

6) lung cancer. Stocks and Campbell found the mortality in nonsmokers in urban areas 10 times larger than rural areas.

7) Heart disease, also found morbiditasnya 2 times greater in areas with high air pollution. Carbon monoxide was found to cause harm to the heart, especially if there are signs of previous ischemic heart disease. Affinity of CO for hemoglobin is 210 times greater than the O2 so if COI-Ib levels equal to or greater than 50%, akin to the heart muscle necrosis. Levels lower than it had been able to disrupt the function of the heart. Scharf et al (1974) reported a case with myocardial infarction after exposure to CO transmural.

8) gastric cancer, found 2 times Iebih much in areas with high pollution.

9) Other diseases, for example irritation of eyes, skin and so many are linked to air pollution. Also children's growth disorders and hematologic abnormalities ever published. In Russia never found barriers to influenza vaccin antibody formation in urban areas with high pollution levels, while in other areas the normal formation.In Japan now officially recognized by the central and local governments, a number of 7 kinds of diseases related to pollution (pollution related diseases). namely:

 Bronchitis chronica

 Asthma bronchiale

 Asthrnatik bronchitis

 Pulmonum emphysema and its complications

 Minamata disease (due to contamination with methyl-Hg)

 Itai-itai disease (due to cadmium poisoning khronik)

 Chronic arsenic poisoning (water and air pollution in the U.S. tambangtambang). People with a valid description of the disease, which is thought to be caused by one of the hazards of pollution, will receive compensation due to losses and maintenance costs of illness by polluters.Waste GasThere are several methods that have been developed for simplification of exhaust gas. Basic development is done is absorption, burning, absorbing ions, neutralization and cleaning swimming particles.Equipment selection on the basis of the following factors:- Type of contaminants (pollutants)- Composition- Concentration- Speed ​​of water pollutants- The toxicity of pollutants- Density- Reactivity- Environmental conditionsEquipment design variables are adjusted to obtain maximum efficiency.The difficulty is often formed in inventory tool on the market.Desired design option does not comply with the conditions of waste, because it had formed a new design. Ability to design equipment requires special skill and it is a problem anyway.In addition, there are other factors that should be considered is the economic value of the equipment. Do not include most of the investment in equipment that would have to be charged at the cost of production. The problem is that later turned out to be a load control consumer costs.On the basis of this reasoning the choice of technology. Processing should be a good consumer protection policy from the point of pollution itself and in terms of cost.In general, the type of pollutants through the air consists of an assortment of chemical compounds in the form of waste and toxic and hazardous materials stored in the factory.Waste gas, smoke and dust through the air are:

1. Dust: The form of fine solids

2. Carbon monoxide: Gas is colorless and odorless

3. Carbon dioxide: gas, colorless, odorless

4. Oxides of nitrogen: gas, colorless and odorless

5. Smoke: A mixture of gases and particles are black: CO2 and SO2

6. Sulfur dioxide: Colorless and sharp herbau

7. Caustic Soda: Crystal

8. Acid chloride: The form of the solution and vapor

9. Sulfuric acid: viscous liquid

10. Ammonia: Gas is colorless, odorless

11. Lead: colorless gas

12. Nitro Carbon: colorless gas

13. Hydrogen fluoride: Gas colorless

14. Nitrogen sulfide: Gas, smell

15. Chlor: Gas, solvents and smelled

16. Mercury: Colorless, solvent