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CHE 680 LEADERSHIP AND PROFESSIONAL ETHICS FOR ENGINEERS CASE STUDIES BRIGHT SPARKLERS FIRE AND EXPLOSIONS Prepared for: PROF. IR. DR. NADIAHNOR MD YUSOF Prepared by: NAMES

STUDENT ID

NUR ALLIENA BT SHARIF

2016249806

NUR MUNIRAH BT AHMAD RIZAL

2016249912

SITI ZAINAB BINTI CHE MAT

2016250028

MUHAMMAD IZZAIRY IZNY BIN

2016249948

IBRAHIM NUR FATIHAH BT ABDUL RAHMAN MOHD AMIRRUSYAIDI BIN MAZLAN

2016249808 2016238956

1. INTRODUCTION a) Definition of emission and incineration Emission can be defined as the production and discharge of something, especially gas or radiation. While incineration is a waste treatment process that involves the combustion of organic substances contained in waste materials. Incineration and other high-temperature waste treatment systems are described as "thermal treatment". Incineration of waste materials can converts the waste into ash, flue gas and heat. Incinerator can be understand more precisely as a furnace where waste is burnt.

b) History of the incinerator The first one who build the incinerators for waste disposal are Manlove, Alliott & Co. Ltd. In in Notthingham (1874). It is a design patented by Albert Fryer. They were originally known as a destructor. In 1885, the first US incinerator was built on Governors Island in New York, NY. The first incineration facility was built in 1905 in Czech Republic in Brno.

c) How does incinerator works in past In some countries, incinerators just built a decades ago which not include a materials separation. In past, incineration was conducted without separating materials which causing harm to environment. This un-separated waste was not free from bulky and recyclable materials. This resulted in risk for plant workers health and environment. Most of such plants and incinerations never generate electricity.

d) Current incineration technology Incineration and coupled with other high temperature waste treatment systems are described as ‘thermal treatment’. Thermal treatment is involving high temperatures in the processing of the waste feedstock in any waste treatment technology. It is commonly involves the combustion of waste materials. Systems that can generally considered as a thermal treatment are cement kiln, gasification, mechanical heat treatment, pyrolysis, and waste autoclaves. Incineration of waste materials converts the waste into ash, flue gas, particles and also heat which later can be to generate the electricity. The gases (flue gases) are first treated for eradication of pollutants before going in

to atmosphere. Eradication of pollutants is the process of reducing or eliminating release pollutants to the atmosphere or environment. Among the waste-to-energy technologies, incineration can be considered as the best. Other technologies are gasification, PDG, anaerobic digestion and Pyrolysis. Sometimes incineration is conducted without the reason for recovering energy. Incineration lessen the mass of the waste from 95 to 96 percent. This minimization of the waste depends upon the recovery degree and composition of materials. This means that incineration does not replace the need for landfilling but it decrease the amount of waste to be thrown. Incineration has its own benefits in specific areas like in medical wastes and other life risking waste. In this process, when waste is treated at high temperature toxins are demolished completely. In Japan, incineration or thermal treatment of waste is much popular because there is scarcity of land. Countries like Denmark and Sweden are highly demanded the energy generated by the incineration. In year, 2005 it was estimated that 4.8 percent of the electricity as is consumed by Danish nation was produced by incineration and the amount of heat was some 13.7 percent out of total. Many European countries are recovering heat and electricity from waste.

2. TYPES OF INCINERATOR 1. Burn pile

Burn pile is one of the earliest form of incineration because it is the easiest one to do. All you need to do is pile up all combustible waste onto the ground and set the whole thing on fire. Burn pile is one of the earliest form of open burning.

2. Burn Barrel

Unlike burn pile, we need to collect all combustible waste and put them into the barrel before burning them. An expanded metal screen with holes will usually cover up the top of the barrel.

3. Rotary Kiln

Rotary kiln incinerators, like the other types, are designed with a primary chamber, where the waste is heated and volatilized, and a secondary chamber, where combustion of the volatile fraction is migrate from the feed end to the ash discharge end. The waste throughput rate is controlled by adjusting the rate of kiln rotation and the angle of inclination. Volatiles and combustion gases pass from the primary chamber to the secondary chamber. The secondary chamber operates at excess air. Combustion of the volatiles is completed in the secondary chamber.

4. Fixed grate

It is a brick-lined cell oven with an opening on top or sides for loading and another opening on the side for removing the solid residue. A fixed metal grate usually covers the top of the ash pit. The waste will be loaded into the oven through the opening and once it is in the oven the waste will be burn before they are removed from the oven through another opening.

5. Fluidized Bed

Fluidized bed combustion (FBC) is a method of burning coal in a bed of heated particles suspended in a gas flow. At sufficient flow rates, the bed acts as a fluid resulting in rapid mixing of the particles. Coal is added to the bed and the continuous mixing encourages complete combustion. Air is blown at high speed over a sand bed. The air gets going through the bed when a point come where sand granules separates and let air pass through them and here comes the part of mixing. A fluidized bed comes in to being and fuel and waste are then can be introduced.

6. Moving Grate Waste is poured into the grate with a help of crane from and opening. From here, the waste moved towards the ash pit. Waste is further treated and water locks wash out the ash from it. Air is then blown through the waste and this blown air works for cooling down the grate. Some of grates are cooled with the help of water. Air is blown through the boiler for another time but this time comparatively faster than before. This air helps in completely burning the flue gases with the introduction of turmoil leading to better mixing and excess of oxygen. In some grates, the combustion air at fast speed is blown in separate chamber.

7. Special Incineration When it comes to the furniture factory for incineration of the waste, they need to take special precautions, as they have to handle resin powder and many flammable substances. For this purpose, they have incinerators, which are installed with burn back prevention systems and are very much necessary for the dust suspensions when they are more able to catch up the fire.

3. HOW DOES INCINERATION CAUSE EMISSION? Nowadays, incinerators are outfitted with thorough contamination control innovations to diminish the discharges of possibly poisonous synthetic concoctions. The utilization of these frameworks extraordinarily decreases, however does not dispose of the emanations of synthetic concoctions from incinerators. Likewise, similarly as with any innovation, there is dependably the danger of mishaps of different sorts, which on account of an incinerator could result in a generally uncontrolled emanation of contaminations for some timeframe. The heater is intended to create great blending of the ignition air and the gases and vapours originating from the consuming waste. All things considered, in parts of the heater where ignition is not finished (for instance, close to the dividers of the heater), flammable segments of natural mixes are scorched off, leaving the incombustible particulate issue known as fly fiery remains entrained in the vent gas. The incombustible segment of the waste (known as base fiery debris) is abandoned. Cremation offices fuse various general strategies for guaranteeing appropriate burning and lessening outflows. An unfaltering circumstance with no significant variances in the waste-feed supply rate, ignition wind currents, or other burning conditions advances proficient burning. Wasteful burning can result in larger amounts of results of fragmented ignition. (Freeman, 2000) Similarly, the more frequently an office is begun up and close down (for upkeep or as a result of deficient or fluctuating waste stream volume), the more uneven the burning and the more prominent the potential for expanded emanations. The most widely recognized burning gas cooling methods for incinerators are squander warm boilers, and direct-contact water-splash extinguishes. Squander warm boilers are utilized on all new city strong waste-to-vitality plants, numerous perilous waste incinerators, and a portion of the bigger medicinal waste incinerators. Squander to-vitality plants have brilliant water divider heaters and additionally convective kettle segments. Dangerous waste and medicinal waste incinerators more often than not have quite recently convective kettle areas, normally of flame tube as opposed to water-tube structure. Most risky waste and medicinal waste incinerators, especially the littler units, don't have warm recuperation boilers. Ignition gases are extinguished by water splashes atomized into the hot gas

stream. Other, less normal, gas-temperature decrease strategies incorporate air-to-gas warm exchangers and direct gas hardening with air. Gas cooling methods are basic to burning framework structure, and can be critical regarding outflows of specific poisons. As talked about later in this part, emanations of mercury and dioxins and furans can be influenced by the rate of gas cooling and the air contamination control gadget (APCD) working temperature. Dry APCDs, including scrubbers and particulate control gadgets, accomplish the most astounding level of decrease of mercury, dioxins and furans, and corrosive gases when pipe gas temperatures are brought down to about 300°F or less at the APCD delta. The burning procedure produces two kinds of fiery debris. Base cinder originates from the heater and is blended with slag, while fly fiery debris originates from the stack and contains parts that are increasingly risky. In metropolitan waste incinerators, base slag is roughly 10% by volume and around 20 to 35% by weight of the strong waste info. Fly fiery debris amounts are much lower, by and large just a couple of percent of info. Emanations from incinerators can incorporate substantial metals, dioxins and furans, which might be available in the waste gases, water or powder. Plastic and metals are the significant wellspring of the calorific estimation of the waste. The ignition of plastics, as polyvinyl chloride (PVC) offers ascend to these very dangerous contaminations.

Toxics are made at different phases of such warm advancements, and not just toward the finish of the stack. These can be made amid the procedure, in the stack channels, as build ups in slag, scrubber water and channels, and in actuality even in air tufts which leave the stack. There are no sheltered methods for keeping away from their generation or pulverizing them, and, best case scenario they can be caught at outrageous expense in refined channels or in the fiery debris. A definitive discharge is unavoidable, and whenever caught in slag or channels, these end up unsafe squanders themselves. The waste-to-vitality program to boost vitality recuperation is mechanically incongruent with lessening dioxins discharges. Dioxins are the most deadly Persistent Organic Pollutants (POPs) which have hopeless ecological wellbeing outcomes. The influenced masses incorporates those

living close to the incinerator and additionally those living in the more extensive locale. Individuals are presented to toxics mixes in a few different ways: • By breathing the air which influences the two laborers in the plant and individuals who live close-by; • By eating privately created sustenance or water that have been defiled via air poisons from the incinerator; and • By eating fish or natural life that have been debased by the air emanations. Dioxin is a profoundly lethal compound which may cause malignancy and neurological harm, and disturb (zafar, 2008) reproductive frameworks, thyroid frameworks, respiratory frameworks and so on. One of numerous factors that influence incinerator activity are controlled by administrators, so the burning conditions that control outflow rates might be considerably influenced by administrator choices. Poor administrator control both of the heater (by allowing temperature or oxygen fixation to diminish) or of the stirring task can cause decreased burning effectiveness. In many incinerators, blending and charging of waste into the incinerator, grind speed, over-flame and under-flame air-infusion rates, and choice of the temperature set point for the helper burner are altogether or incompletely controlled by plant work force. Moreover, the degree of discharge control accomplished by post-burning APCDs relies upon how the gadgets are worked. Problematic task can be caused by ineffectively prepared or scatter brained administrators, broken methodology, and gear disappointment. Administrators must be mindful to the stream rate of waste into the incinerator and heater task to take into account compelling capacity of APCDs. Albeit the absolute most-current cremation gear has been robotized, there will dependably be a requirement for administrators to manage surprising circumstances. Also, mechanized hardware requires alignment and support, and combustor parts can destroy or glitch. Instances of what can turn out badly incorporate stopped up air infusion into the burning chamber, fouled kettle tubes, an opening in the texture channels, and an obstructed scrubber spout.

4. TYPE OF EMMISION I.

Dioxin and furan

II.

Carbon dioxide

III.

Nitrogen oxides

IV.

Sulfur dioxide

V.

Heavy metals

Effects of the emmisions A. Dioxins and furans Dioxins and furans are considered by many to be serious health hazards. The EPA announced in 2012 that the safe limit for human oral consumption is 0.7 picograms Toxic Equivalence (TEQ) per kilogram bodyweight per day, which works out to 17 billionths of a gram for a 150lb person per year. Short-term exposure of humans to high levels of dioxins may result in skin lesions, such as chloracne and patchy darkening of the skin, and altered liver function. Long-term exposure is linked to impairment of the immune system, the developing nervous system, the endocrine system and reproductive functions. Chronic exposure of animals to dioxins has resulted in several types of cancer. TCDD was evaluated by the WHO’s International Agency for Research on Cancer (IARC) in 1997 and 2012. Based on animal data and on human epidemiology data, TCDD was classified by IARC as a "known human carcinogen”. However, TCDD does not affect genetic material and there is a level of exposure below which cancer risk would be negligible. Due to the omnipresence of dioxins, all people have background exposure and a certain level of dioxins in the body, leading to the so-called body burden. Current normal background exposure is not expected to affect human health on average. However, due to the high toxic potential of this class of compounds, efforts need to be undertaken to reduce current background exposure.

B. Carbon dioxide

As for other complete combustion processes, nearly all of the carbon content in the waste is emitted as CO2 to the atmosphere. MSW contains approximately the same mass fraction of carbon CO2 itself (27%), so incineration of 1 ton of MSW produces approximately 1 ton of CO2. Carbon dioxide contributes to air pollution in its role in the greenhouse effect. Carbon dioxide traps radiation at ground level, creating ground-level ozone. This atmospheric layer prevents the earth from cooling at night. One result is a warming of ocean waters. Oceans absorb carbon dioxide from the atmosphere. However, higher water temperatures compromise the oceans' ability to absorb carbon dioxide. Over time, the effects of carbon dioxide are compounded. Another environmental effect of

carbon dioxide on air pollution is climate change. The earth's surface temperature has risen over the last 100 years, according to studies done by the National Oceanic and Atmospheric Administration (NOAA). Scientists believe carbon dioxide pollution is the primary culprit. The effects are highly complex. Evidence shows, however, that ocean water levels have increased, resulting in a loss of shoreline and coastal wetlands.

C. Nitrogen oxides Nitrous oxide is a colorless and odorless substance that’s also known as “laughing gas.” When inhaled, the gas slows down the body’s reaction time. This results in a calm, euphoric feeling. Nitrous oxide can be used to treat pain. It also functions as a mild sedative. Because of this, it’s sometimes used before dental procedures to promote relaxation and reduce anxiety. Nitrous oxide gas works fast as a sedative, but it doesn’t take long for the effects to wear off. Nitrous oxide is safe. But like any type of drug, side effects may occur. Here’s a look at the potential side effects of nitrous oxide. Common short-term side effects include: 

Excessive sweating



Shivering



Nausea



Vomiting



Dizziness



Fatigue

Some people also experience hallucinations or sound distortion after inhaling nitrous oxide.

D. Sulfur dioxide Sulfur dioxide (SO2) is a colorless gas with a sharp, irritating odor. It is produced by burning fossil fuels and by the smelting of mineral ores that contain sulfur. Erupting volcanoes can be a significant natural source of sulfur dioxide emissions. Environmental effects When sulfur dioxide combines with water and air, it forms sulfuric acid, which is the main component of acid rain. Acid rain can: 

cause deforestation



acidify waterways to the detriment of aquatic life



the corrosion of building materials and paints.

In Queensland, there is less heavy industry than in Europe or North America, where the potential for forming acid rain from sulfur dioxide emissions is higher. Our weather conditions and low sulfur content of fuels reduce the potential for acid rain. Health effects Sulfur dioxide affects the respiratory system, particularly lung function, and can irritate the eyes. Sulfur dioxide irritates the respiratory tract and increases the risk of tract infections. It causes coughing, mucus secretion and aggravates conditions such as asthma and chronic bronchitis.

E. Heavy metals

Heavy metals are toxic to soil, plants, aquatic life and human health if their concentration is high in the compost. Heavy metals exhibit toxic effects towards soil biota by affecting key microbial processes and decrease the number and activity of soil microorganisms. Even low concentration of heavy metals may inhibit the physiological metabolism of plant. Uptake of heavy metals by plants and subsequent accumulation along the food chain is a potential

threat to animal and human health. Contaminants in aquatic systems, including heavy metals, stimulate the production of reactive oxygen species (ROS) that can damage fishes and other aquatic organisms. Hence the compost has to be used for agriculture it should be free from heavy metals. Therefore, the present study evaluated the effects of heavy metal containing compost on soil, plants, human health and aquatic life.

5. Emission Control Devices 1) Activated Carbon -

Granular activated carbon is a highly adsorbent material used to remove contamination from water.

-

Activated carbon has been known as a miracle filter media by many researchers because of its unique ability to remove offensive tastes, odors, color, chlorine and volatile organic chemicals and pesticides.

-

Briefly, activated carbon acts like a sponge, with a large surface area to absorb contaminants in the water. The surface area of one pound of activated carbon is equal to 125 acres.

-

Many scientists believe this is a result of an affinity that these chemicals have for carbon because of Van Der Waal forces.

-

Activated carbon is the preferred treatment and method to remove a host of potentially hazardous and possibly carcinogenic chemicals in drinking water.

-

Activated carbon acts as a treatment for the public water systems. Several chemicals that are reduced or removed by activated carbon are: i) Chlorobenzene (Affects nervous system, kidneys and liver) (Used as a solvent for paint and metal manufacturing) ii) Toluene (Cancer) (Used in gasoline, paint thinners, lacquers and adhesives.) iii) Ethylene Dibromide (Affects nervous system, kidneys and liver) (Used as a gasoline additive and soil fumigant.) iv) Epichlorohydrin (Affects nervous system, kidneys and liver) (Used in epoxy resins and coating, and in flocculants.) v) Monochlorobenzene (Cancer) (Used in manufacture of pesticides and as a metal cleaner and industrial solvent.) vi) Chloroform (Affects kidney, liver and can cause nausea) (Used in manufacturing dyes, plastic, perfumes, paints and adhesives)

2) Baghouse -

A baghouse, bag filter or fabric filter is an air pollution control device and dust collector that removes particulates out of air or gas released from commercial processes or combustion for electricity generation.

-

Power plants, steel mills, pharmaceutical producers, food manufacturers, chemical producers and other industrial companies often use baghouses to control emission of air pollutants.

-

The baghouse is a system in which air is filtered by bags made of various materials, which are periodically cleaned to remove the accumulated dust.

-

Generally, all baghouses have a tube sheet to which the bags are attached, an inlet for dirty air and an outlet for clean air, and an opening at the bottom for collected dust to drop out. The location of these features depends on the type of baghouse.

-

The main differences between types of baghouses is how the bags are kept clean.

-

Types of baghouse : i) Mechanical shakers 

In mechanical-shaker baghouses, tubular filter bags are fastened onto a cell plate at the bottom of the baghouse and suspended from horizontal beams at the top.



Dirty gas enters the bottom of the baghouse and passes through the filter, and the dust collects on the inside surface of the bags.

ii) Reverse air 

In reverse-air baghouses, the bags are fastened onto a cell plate at the bottom of the baghouse and suspended from an adjustable hanger frame at the top.



Dirty gas flow normally enters the baghouse and passes through the bag from the inside, and the dust collects on the inside of the bags.

iii) Pulse jet 

In reverse pulse-jet baghouses, individual bags are supported by a metal cage (filter cage), which is fastened onto a cell plate at the top of the baghouse.



Dirty gas enters from the bottom of the baghouse and flows from outside to inside the bags. The metal cage prevents collapse of the bag.

3) Electrostatic precipitator -

An electrostatic precipitator (ESP) is a filtration device that removes fine particles, like dust and smoke, from a flowing gas using the force of an induced electrostatic charge minimally impeding the flow of gases through the unit.

-

The most basic precipitator contains a row of thin vertical wires, and followed by a stack of large flat metal plates oriented vertically, with the plates typically spaced about 1 cm to 18 cm apart, depending on the application.

-

The air stream flows horizontally through the spaces between the wires, and then passes through the stack of plates.

-

A negative voltage of several thousand volts is applied between wire and plate. If the applied voltage is high enough, an electric corona discharge ionizes the air around the electrodes, which then ionizes the particles in the air stream.

-

The ionized particles, due to the electrostatic force, are diverted towards the grounded plates. Particles build up on the collection plates and are removed from the air stream.

6. ADVANTAGES AND DISADVANTAGES OF INCINERATORS Solid waste incinerators are used to combust organic substances contained in waste. Incineration converts solid waste into ash, flue gas and heat. It is the main alternative to landfills, which hold solid waste in a contained area. Modern solid waste incinerators separate most dangerous gases and particulates from the flue gas produced during incineration. There are many advantages and disadvantages of using the incinerator. One of the advantages using the incinerator is it can reduce volume of solid waste. Incinerators can reduce waste volume by approximately 95 percent and reduce the solid mass of the original waste by 80 percent to 85 percent. Incineration does not eliminate the need for dumping ground completely, it certainly reduces the amount of land needed. Next, the advantages is it generate power and heat generation. As energy costs went up in the 1950s, numerous countries sought to incorporate the energy and heat generated from garbage incinerators for the production of electricity through steam turbines. For example, at Sweden produces 8 percent of its heating needs from 50 percent of the waste incinerated. On the other hand, the advantage is it can reduce pollution. According to studies it have shown that solid waste incinerators produce less pollution than landfills. One study in particular, conducted during a 1994 lawsuit in the United States, showed that a waste incinerator site was more environmentally friendly than an equivalent landfill. The study found that the landfill released higher amounts of greenhouse gases, hydrocarbons, non-methane organic compounds, hazardous air pollutants, nitrogen oxides and dioxin than an incinerator. Lastly, incinerator can filter trap pollutants. A major concern associated with incinerating solid waste was the release of dangerous compounds, dioxin in particular. Modern incinerators use filters to trap dangerous gases and particulate matter like dioxin. The release of dioxin by most modern incinerators is good within the recommended limits prescribed by the Environmental Protection Agency and international protocols.

For the disadvantages of incinerators, one of it is installation of incinerator is expensive. Incinerator is built in the incineration plant so the costs of constructing the infrastructure to the costs of operating the incineration plants are very high. Besides, an incineration plant requires

trained personnel and devoted staff to man its operation. Incinerator plants also need regular maintenance, which adds to the already high costs of operating it. Next, the disadvantages of incinerators is it pollute the environment. Incinerators produce smoke during the burning process. The smoke produced includes acid gases, carcinogen dioxin, particulates, heavy metals, and nitrogen oxide. These gases are poisonous to the environment. Research has shown that dioxin produced in the plant is a cancer forming chemical. It causes atmospheric pollution if incinerators are not well maintained It also have the possibility of long-term problems. Incineration does not encourage recycling and waste reduction. Reducing waste and recycling most should be focused on it. Burning most of the waste without recycling some of it will only further environmental damage because it may encourage more waste production. Lastly, incinerator produce ash waste which can potentially harm people and the environment. Even though the ash that remains from the process can be comparatively small in quantity, it contains a number of poisons and heavy metals which requires further treatment. If not disposed correctly, it can cause serious harm to the public and the environment.

7. CONCLUSION Waste-incineration technology and practice can be implemented under conditions that meet currently applicable and proposed emissions limits and other environmental regulatory constraints. The characteristics of incineration emissions and residual ash are affected by the wastes fed to an incineration facility, its combustion efficiency, and the degree of emission control of that facility. Next , the combustion efficiency of an incineration process can be improved by optimizing combustor operations which will reduce the quantity of soot produced and lessen the formation of PICs, such as dioxins and furans. However, the potential to increase the heavy-metal content in the emissions due to volatilization resulting from the higher combustion temperatures needed to improve combustion efficiency. Emissions from incineration facilities are reduced by modifying operating characteristic such as furnace temperature, air-injection rate, flue-gas temperature, reagent type, and injection rate, and by selecting optimal combustor designs and emission-control technologies. Continuous emission monitors for CO, O2, SOx, NOx, and HCl are available and have been certified by jurisdictions in this country and in other countries. CEMs for particulate matter and total mercury are under development and are in the process of being certified. Emissions from incineration facilities also can be reduced by choosing advanced combustion designs and emission-control technologies for the pollutant of concern and by having well-trained and certified employees who can help to ensure that the combustor is operated to maximize combustion efficiency and that the emission control devices are operated to optimize conditions for pollutant capture or neutralization.

REFERENCES: https://www.bioenergyconsult.com/moving-grate-incineration/ (Retrieved Dec 11th, 2018) http://www.chavond-barry.com/fluidized-bed-incinerators.html (Retrieved Dec 11th, 2018) Freeman, W. (2000). Incineration Processes and Environmental Releases. National Academy of Sciences. zafar, s. (september 2008). negative impacts of incineraton based to waste technology. Retrieved from http://www.alternative-energy-news.info/negative-impacts-waste-to-energy/ Kwak, P. S. ( 2018, March 13). https://sciencing.com. Retrieved from https://sciencing.com/advantages-solid-waste-incinerator-8367212.html Rinkesh. Retrieved from http://www.conserve-energy-future.com/advantages-and-disadvantagesincineration.php http://www.cabotcorp.com/solutions/applications/air-purification/automotive-emissioncontrol https://crystalquest.com/pages/how-activated-carbon-works

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