Pfizer Inc. is an American multinational pharmaceutical corporation headquartered in New York City, with its research headquarters in Groton, Connecticut. It is one of the world's largest pharmaceutical companies, it is listed on the New York Stock Exchange, its shares have been a component of the Dow Jones Industrial Average since 2004. Pfizer ranked No. 57 on the 2018 Fortune 500 list of the largest United States corporations by total revenue. On December 19, 2018, Pfizer announced a joint merger of their consumer healthcare division with UK pharma giant GlaxoSmithKline; the company develops and produces medicines and vaccines for a wide range of medical disciplines, including immunology, cardiology and neurology. Its products include the blockbuster drug Lipitor, used to lower LDL blood cholesterol. In 2016, Pfizer Inc. was expected to merge with Allergan, Plc to create the Ireland-based "Pfizer plc" in a deal that would have been worth $160 billion. The merger was called off in April 2016, because of new rules from the United States Treasury against tax inversions, a method of avoiding taxes by merging with a foreign company.
The company has made the second-largest pharmaceutical settlement with the United States Department of Justice. Pfizer was founded in 1849 by German-American Charles Pfizer and his cousin Charles F. Erhart from Ludwigsburg, Germany, they launched the chemicals business Charles Pfizer and Company from a building at the intersection of Harrison Avenue and Bartlett Street in Williamsburg, where they produced an antiparasitic called santonin. This was an immediate success, although it was the production of citric acid that kick-started Pfizer's growth in the 1880s. Pfizer continued to buy property to expand its lab and factory on the block bounded by Bartlett Street, Harrison Avenue, Gerry Street, Flushing Avenue. Pfizer's original administrative headquarters was at 81 Maiden Lane in Manhattan. By 1906, sales totaled $3.4 million. World War I caused a shortage of calcium citrate which Pfizer imported from Italy for the manufacture of citric acid, the company began a search for an alternative supply.
Pfizer chemists learned of a fungus that ferments sugar to citric acid, they were able to commercialize production of citric acid from this source in 1919, the company developed expertise in fermentation technology as a result. These skills were applied to the mass production of the antibiotic penicillin during World War II in response to the need to treat injured Allied soldiers. Penicillin became inexpensive in the 1940s, Pfizer searched for new antibiotics with greater profit potential, they discovered Terramycin in 1950, this changed the company from a manufacturer of fine chemicals to a research-based pharmaceutical company. Pfizer developed a drug discovery program focusing on in vitro synthesis in order to augment its research in fermentation technology; the company established an animal health division in 1959 with an 700-acre farm and research facility in Terre Haute, Indiana. By the 1950s, Pfizer had established offices in Belgium, Canada, Mexico, Puerto Rico, the United Kingdom. In 1960, the company moved its medical research laboratory operations out of New York City to a new facility in Groton, Connecticut.
In 1980, they launched Feldene, a prescription anti-inflammatory medication that became Pfizer's first product to reach one billion dollars in total sales. During the 1980s and 1990s, Pfizer Corporation growth was sustained by the discovery and marketing of Zoloft, Norvasc, Aricept and Viagra. In this decade, Pfizer grew by mergers, including those with Warner–Lambert and Wyeth. In 2003, the company acquired Esperion Therapeutics for $1.3 billion, protecting Lipitor from ETC-216. In 2004, Pfizer announced. In 2005, the company made a number of acquisitions: Vicuron Pharmaceuticals for $1.9 billion, Idun for just less than $300 million and Angiosyn for $527 million. On June 26, 2006, Pfizer announced it would sell its Consumer Healthcare unit to Johnson & Johnson for $16.6 billion. Development of torcetrapib, a drug that increases production of HDL, or "good cholesterol", which reduces LDL thought to be correlated to heart disease, was cancelled in December 2006. During a Phase III clinical trial involving 15,000 patients, more deaths occurred in the group that took the medicine than expected, a sixty percent increase in mortality was seen among patients taking the combination of torcetrapib and Lipitor versus Lipitor alone.
Lipitor alone was not implicated in the results, but Pfizer lost nearly $1 billion developing the failed drug and the market value of the company plummeted afterwards. The company announced it would acquire Powermed and Rivax. In September 2009, Pfizer pleaded guilty to the illegal marketing of the arthritis drug Bextra for uses unapproved by the U. S. Food and Drug Administration, agreed to a $2.3 billion settlement, the largest health care fraud settlement at that time. A July 2010 article in BusinessWeek reported that Pfizer was seeing more success in its battle against makers of counterfeit prescription drugs by pursuing c
Volkswagen AG, known internationally as the Volkswagen Group, is a German multinational automotive manufacturing company headquartered in Wolfsburg, Lower Saxony and indirectly majority owned by the Austrian Porsche-Piëch family. It designs and distributes passenger and commercial vehicles, motorcycles and turbomachinery and offers related services including financing and fleet management. In 2016, it was the world's largest automaker by sales, overtaking Toyota and keeping this title in 2017 and 2018, selling 10.8 million vehicles. It has maintained the largest market share in Europe for over two decades, it ranked seventh in the 2018 Fortune Global 500 list of the world's largest companies. Volkswagen Group sells passenger cars under the Audi, Bugatti, Porsche, SEAT, Škoda and the flagship Volkswagen marques, it is divided into two primary divisions, the Automotive Division and the Financial Services Division, as of 2008 had 342 subsidiary companies. Volkswagen has two major joint-ventures in China.
The company has operations in 150 countries and operates 100 production facilities across 27 countries. Volkswagen was founded in 1937; the company's production grew in the 1950s and 1960s, in 1965 it acquired Auto Union, which subsequently produced the first post-war Audi models. Volkswagen launched a new generation of front-wheel drive vehicles in the 1970s, including the Passat and Golf. Volkswagen acquired a controlling stake in SEAT in 1986, making it the first non-German marque of the company, acquired control of Škoda in 1994, of Bentley and Bugatti in 1998, Scania in 2008 and of Ducati, MAN and Porsche in 2012; the company's operations in China have grown in the past decade with the country becoming its largest market. In June 2018, Volkswagen Trucks and Buses which comprises the MAN, RIO truck brands are renamed to TRATON AG but the marques will not change, said by Andreas Renschler. Volkswagen Aktiengesellschaft is a public company and has a primary listing on the Frankfurt Stock Exchange, where it is a constituent of the Euro Stoxx 50 stock market index, secondary listings on the Luxembourg Stock Exchange, SIX Swiss Exchange.
It has been traded in the United States via American depositary receipts since 1988 on the OTC Marketplace. Volkswagen delisted from the London Stock Exchange in 2013; the state of Lower Saxony holds 12.7 % of the company's shares. Volkswagen was founded on 28 May 1937 in Berlin as the Gesellschaft zur Vorbereitung des Deutschen Volkswagens mbH by the National Socialist Deutsche Arbeitsfront; the purpose of the company was to manufacture the Volkswagen car referred to as the Porsche Type 60 the Volkswagen Type 1, called the Volkswagen Beetle. This vehicle was designed by Ferdinand Porsche's consulting firm, the company was backed by the support of Adolf Hitler. On 16 September 1938, Gezuvor was renamed Volkswagenwerk GmbH. Shortly after the factory near Fallersleben was completed, World War II started and the plant manufactured the military Kübelwagen and the related amphibious Schwimmwagen, both of which were derived from the Volkswagen. Only a small number of Type 60 Volkswagens were made during this time.
The Fallersleben plant manufactured the V-1 flying bomb, making the plant a major bombing target for the Allied forces. After the war in Europe, in June 1945, Major Ivan Hirst of the British Army Royal Electrical and Mechanical Engineers took control of the bomb-shattered factory, restarted production, pending the expected disposal of the plant as war reparations. However, no British car manufacturer was interested. To build the car commercially would be a uneconomic enterprise". In 1948, the Ford Motor Company of USA was offered Volkswagen, but Ernest Breech, a Ford executive vice president said he didn't think either the plant or the car was "worth a damn." Breech said that he would have considered merging Ford of Germany and Volkswagen, but after the war, ownership of the company was in such dispute that nobody could hope to be able to take it over. As part of the Industrial plans for Germany, large parts of German industry, including Volkswagen, were to be dismantled. Total German car production was set at a maximum of 10% of the 1936 car production numbers.
The company survived by producing cars for the British Army, in 1948 the British Government handed the company back over to the German state, it was managed by former Opel chief Heinrich Nordhoff. Production of the Type 60 Volkswagen started after the war due to the need to rebuild the plant and because of the lack of raw materials, but production grew in the 1950s and 1960s; the company began introducing new models based on the Type 1, all with the same basic air-cooled, rear-engine, rear-drive platform. These included the Volkswagen Type 2 in 1950, the Volkswagen Karmann Ghia in 1955, the Volkswagen Type 3 in 1961, the Volkswagen Type 4 in 1968, the Volkswagen Type 181 in 1969. In 1960, upon t
Manufacturing Engineering is a branch of professional engineering. Manufacturing engineering requires the ability to plan the practices of manufacturing; the manufacturing or production engineer's primary focus is to turn raw material into an updated or new product in the most effective, efficient & economic way possible. Manufacturing Engineering is based on core industrial engineering and mechanical engineering skills, adding important elements from mechatronics, commerce and business management; this field deals with the integration of different facilities and systems for producing quality products by applying the principles of physics and the results of manufacturing systems studies, such as the following: Manufacturing engineers develop and create physical artifacts, production processes, technology. It is a broad area which includes the design and development of products. Manufacturing engineering is considered to be a subdiscipline of industrial engineering/systems engineering and has strong overlaps with mechanical engineering.
Manufacturing engineers' success or failure directly impacts the advancement of technology and the spread of innovation. This field of manufacturing engineering emerged from tool and die discipline in the early 20th century, it expanded from the 1960s when industrialized countries introduced factories with: 1. Numerical control automated systems of production. 2. Advanced statistical methods of quality control: These factories were pioneered by the American electrical engineer William Edwards Deming, ignored by his home country; the same methods of quality control turned Japanese factories into world leaders in cost-effectiveness and production quality. 3. Industrial robots on the factory floor, introduced in the late 1970s: These computer-controlled welding arms and grippers could perform simple tasks such as attaching a car door and flawlessly 24 hours a day; this cut improved production speed. The history of manufacturing engineering can be traced to factories in the mid 19th century USA and 18th century UK.
Although large home production sites and workshops were established in China, ancient Rome and the Middle East, the Venice Arsenal provides one of the first examples of a factory in the modern sense of the word. Founded in 1104 in the Republic of Venice several hundred years before the Industrial Revolution, this factory mass-produced ships on assembly lines using manufactured parts; the Venice Arsenal produced nearly one ship every day and, at its height, employed 16,000 people. Many historians regard Matthew Boulton's Soho Manufactory as the first modern factory. Similar claims can be made for John Lombe's silk mill in Derby, or Richard Arkwright's Cromford Mill; the Cromford Mill was purpose-built to accommodate the equipment it held and to take the material through the various manufacturing processes. One historian, Jack Weatherford, contends that the first factory was in Potosí; the Potosi factory took advantage of the abundant silver, mined nearby and processed silver ingot slugs into coins.
British colonies in the 19th century built factories as buildings where a large number of workers gathered to perform hand labor in textile production. This proved more efficient for the administration and distribution of materials to individual workers than earlier methods of manufacturing, such as cottage industries or the putting-out system. Cotton mills used inventions such as the steam engine and the power loom to pioneer the industrial factories of the 19th century, where precision machine tools and replaceable parts allowed greater efficiency and less waste; this experience formed the basis for the studies of manufacturing engineering. Between 1820 and 1850, non-mechanized factories supplanted traditional artisan shops as the predominant form of manufacturing institution. Henry Ford further revolutionized the factory concept and thus manufacturing engineering in the early 20th century with the innovation of mass production. Specialized workers situated alongside a series of rolling ramps would build up a product such as an automobile.
This concept decreased production costs for all manufactured goods and brought about the age of consumerism. Modern manufacturing engineering studies include all intermediate processes required for the production and integration of a product's components; some industries, such as semiconductor and steel manufacturers use the term "fabrication" for these processes. Automation is used in different processes of manufacturing such as welding. Automated manufacturing refers to the application of automation to produce goods in a factory; the main advantages of automated manufacturing for the manufacturing process are realized with effective implementation of automation and include: higher consistency and quality, reduction of lead times, simplification of production, reduced handling, improved work flow, improved worker morale. Robotics is the application of mechatronics and automation to create robots, which are used in manufacturing to perform tasks that are dangerous, unpleasant, or repetitive.
These robots may be of any shape and size, but all are preprogrammed and interact physically with the world. To create a robot, an engineer employs kinematics and mechanics. Robots are used extensively in manufacturing engineering. Robots allow businesses to save money o
Industrial design is a process of design applied to products that are to be manufactured through techniques of mass production. Its key characteristic is that design is separated from manufacture: the creative act of determining and defining a product's form and features takes place in advance of the physical act of making a product, which consists purely of repeated automated, replication; this distinguishes industrial design from craft-based design, where the form of the product is determined by the product's creator at the time of its creation. All manufactured products are the result of a design process, but the nature of this process can take many forms: it can be conducted by an individual or a large team; the role of an industrial designer is to create and execute design solutions for problems of form, usability, physical ergonomics, brand development and sales. For several millennia before the onset of industrialisation, technical expertise, manufacturing were done by individuals craftsmen, who determined the form of a product at the point of its creation, according to their own manual skill, the requirements of their clients, experience accumulated through their own experimentation, knowledge passed on to them through training or apprenticeship.
The division of labour that underlies the practice of industrial design did have precedents in the pre-industrial era. The growth of trade in the medieval period led to the emergence of large workshops in cities such as Florence, Venice and Bruges, where groups of more specialized craftsmen made objects with common forms through the repetitive duplication of models which defined by their shared training and technique. Competitive pressures in the early 16th century led to the emergence in Italy and Germany of pattern books: collections of engravings illustrating decorative forms and motifs which could be applied to a wide range of products, whose creation took place in advance of their application; the use of drawing to specify how something was to be constructed was first developed by architects and shipwrights during the Italian Renaissance. In the 17th century, the growth of artistic patronage in centralized monarchical states such as France led to large government-operated manufacturing operations epitomised by the Gobelins Manufactory, opened in Paris in 1667 by Louis XIV.
Here teams of hundreds of craftsmen, including specialist artists and engravers, produced sumptuously decorated products ranging from tapestries and furniture to metalwork and coaches, all under the creative supervision of the King's leading artist Charles Le Brun. This pattern of large-scale royal patronage was repeated in the court porcelain factories of the early 18th century, such as the Meissen porcelain workshops established in 1709 by the Grand Duke of Saxony, where patterns from a range of sources, including court goldsmiths and engravers, were used as models for the vessels and figurines for which it became famous; as long as reproduction remained craft-based, the form and artistic quality of the product remained in the hands of the individual craftsman, tended to decline as the scale of production increased. The emergence of industrial design is linked to the growth of industrialisation and mechanisation that began with the industrial revolution in Great Britain in the mid 18th century.
The rise of industrial manufacture changed the way objects were made, urbanisation changed patterns of consumption, the growth of empires broadened tastes and diversified markets, the emergence of a wider middle class created demand for fashionable styles from a much larger and more heterogeneous population. The first use of the term "industrial design" is attributed to the industrial designer Joseph Claude Sinel in 1919, but the discipline predates 1919 by at least a decade. Christopher Dresser is considered among the first independent industrial designers. Industrial design's origins lie in the industrialization of consumer products. For instance the Deutscher Werkbund, founded in 1907 and a precursor to the Bauhaus, was a state-sponsored effort to integrate traditional crafts and industrial mass-production techniques, to put Germany on a competitive footing with Great Britain and the United States; the earliest use of the term may have been in The Art Union, A monthly Journal of the Fine Arts, 1839.
Dyce's report to the Board of Trade on foreign schools of Design for Manufactures. Mr Dyces official visit to France and Bavaria for the purpose of examining the state of schools of design in those countries will be fresh in the recollection of our readers, his report on this subject was ordered to be printed some few months since, on the motion of Mr Hume. The school of St Peter, at Lyons was founded about 1750 for the instruction of draftsmen employed in preparing patterns for the silk manufacture, it has been much more successful than the Paris school and having been disorganized by the revolution, was restored by Napoleon and differently constituted, being erected into an Academy of Fine Art: to which the study of design for silk manufacture was attached as a subordinate branch. It appears that all the students who entered the school commence as if they were intended for artists in the higher sense of the word and are not expected to decide as to whether they will devote themselves to the Fine Arts or to Industrial Design, until they have completed their exercises in drawing and p
In product development, an end user is a person who uses or is intended to use a product. The end user stands in contrast to users who support or maintain the product, such as sysops, system administrators, database administrators, information technology experts, software professionals and computer technicians. End users do not possess the technical understanding or skill of the product designers, a fact, easy for designers to forget or overlook, leading to features with which the customer is dissatisfied. In information technology, end users are not "customers" in the usual sense—they are employees of the customer. For example, if a large retail corporation buys a software package for its employees to use though the large retail corporation was the "customer" which purchased the software, the end users are the employees of the company who will use the software at work. Certain American defense-related products and information require export approval from the United States Government under the ITAR and EAR.
In order to obtain a license to export, the exporter must specify both the end user and end use using an end-user certificate. In End-User License Agreements, the end user is distinguished from the value-added reseller that installs the software or the organization that purchases and manages the software. In the UK, there exist documents. End users are one of the three major factors contributing to the complexity of managing information systems; the end user's position has changed from a position in the 1950s to one in the 2010s where the end user collaborates with and advises the management information system and Information Technology department about his or her needs regarding the system or product. This raises new questions such as: Who manages each resource? What is the role of the MIS Department? What is the optimal relationship between the end user and the MIS Department? The concept of "end user" first surfaced in the late 1980s and has since raised many debates. One challenge is that the goal is to both give the user more freedom, by adding advanced features and functions, add more constraints.
This phenomenon appeared as a consequence of "consumerization" of software. In the 1960s and 1970s, computer users were programming experts and computer scientists. However, in the 1980s, in the mid- to late 1990s and the early 2000s, regular people began using computer devices and software for personal and work use. IT specialists need to cope with this trend in various ways. In the 2010s, users now want to have more control over the systems they operate, so they solve their own problems and be able to change, customize and "tweak" the systems to suit their needs; the drawback would be the risk of corruption of the systems and data the user has control of due to his or her lack of knowledge on how to properly operate the computer or software at an advanced level. For companies to appeal to the user, they take care to accommodate and think of end users in their new products, software launches and updates. A partnership needs to be formed between the programmer-developers and the everyday end users so that both parties can make the most out of the products.
Public libraries have been affected by new technologies in many ways, ranging from the digitalization of their card catalog and the shift to e-books and e-journals and offering online services. Libraries have had to undergo many changes in order to cope, including training existing librarians in Web 2.0 and database skills and hiring IT and software experts. The aim of end user documentation is to help the user understand certain aspects of the systems and to provide all the answers in one place. A lot of documentation is available for users to help them understand and properly use a certain product or service. Due to the fact that the information available is very vast, inconsistent or ambiguous, many users suffer from an information overload. Therefore, they become unable to take the right course of action; this needs to be kept in mind when developing products and services and the necessary documentation for them. Well written documentation is needed for a user to reference; some key aspects of such a documentation are: Specific titles and subtitles for subsections to aid the reader in finding sections Use of videos, annotated screenshots and links to help the reader understand how to use the device or program Structured provision of information, which goes from the most basic instructions, written in plain language, without specialist jargon or acronyms, progressing to the information that intermediate or advanced users will need Easy to search the help guide, find information and access information Clear end results are described to the reader Detailed, numbered steps, to enable users with a range of proficiency levels to go step-by-step to install and troubleshoot the product or service Unique Uniform Resource Locator so that the user can go to the product website to find additional help and resources.
At times users do not refer to the documentation available to the
A machine is a mechanical structure that uses power to apply forces and control movement to perform an intended action. Machines can be driven by animals and people, by natural forces such as wind and water, by chemical, thermal, or electrical power, include a system of mechanisms that shape the actuator input to achieve a specific application of output forces and movement, they can include computers and sensors that monitor performance and plan movement called mechanical systems. Renaissance natural philosophers identified six simple machines which were the elementary devices that put a load into motion, calculated the ratio of output force to input force, known today as mechanical advantage. Modern machines are complex systems that consist of structural elements and control components and include interfaces for convenient use. Examples include a wide range of vehicles, such as automobiles and airplanes, appliances in the home and office, including computers, building air handling and water handling systems, as well as farm machinery, machine tools and factory automation systems and robots.
The English word machine comes through Middle French from Latin machina, which in turn derives from the Greek. The word mechanical comes from the same Greek roots. A wider meaning of "fabric, structure" is found in classical Latin, but not in Greek usage; this meaning is found in late medieval French, is adopted from the French into English in the mid-16th century. In the 17th century, the word could mean a scheme or plot, a meaning now expressed by the derived machination; the modern meaning develops out of specialized application of the term to stage engines used in theater and to military siege engines, both in the late 16th and early 17th centuries. The OED traces the formal, modern meaning to John Harris' Lexicon Technicum, which has: Machine, or Engine, in Mechanicks, is whatsoever hath Force sufficient either to raise or stop the Motion of a Body... Simple Machines are reckoned to be Six in Number, viz. the Ballance, Pulley, Wheel and Screw... Compound Machines, or Engines, are innumerable.
The word engine used as a synonym both by Harris and in language derives from Latin ingenium "ingenuity, an invention". The hand axe, made by chipping flint to form a wedge, in the hands of a human transforms force and movement of the tool into a transverse splitting forces and movement of the workpiece; the idea of a simple machine originated with the Greek philosopher Archimedes around the 3rd century BC, who studied the Archimedean simple machines: lever and screw. Archimedes discovered the principle of mechanical advantage in the lever. Greek philosophers defined the classic five simple machines and were able to calculate their mechanical advantage. Heron of Alexandria in his work Mechanics lists five mechanisms that can "set a load in motion". However, the Greeks' understanding was limited to statics and did not include dynamics or the concept of work. During the Renaissance the dynamics of the Mechanical Powers, as the simple machines were called, began to be studied from the standpoint of how much useful work they could perform, leading to the new concept of mechanical work.
In 1586 Flemish engineer Simon Stevin derived the mechanical advantage of the inclined plane, it was included with the other simple machines. The complete dynamic theory of simple machines was worked out by Italian scientist Galileo Galilei in 1600 in Le Meccaniche, he was the first to understand that simple machines do not create energy, they transform it. The classic rules of sliding friction in machines were discovered by Leonardo da Vinci, but remained unpublished in his notebooks, they were rediscovered by Guillaume Amontons and were further developed by Charles-Augustin de Coulomb. James Watt patented his parallel motion linkage in 1782, which made the double acting steam engine practical; the Boulton and Watt steam engine and designs powered steam locomotives, steam ships, factories. The Industrial Revolution was a period from 1750 to 1850 where changes in agriculture, mining and technology had a profound effect on the social and cultural conditions of the times, it began in the United Kingdom subsequently spread throughout Western Europe, North America and the rest of the world.
Starting in the part of the 18th century, there began a transition in parts of Great Britain's manual labour and draft-animal-based economy towards machine-based manufacturing. It started with the mechanisation of the textile industries, the development of iron-making techniques and the increased use of refined coal; the idea that a machine can be decomposed into simple movable elements led Archimedes to define the lever and screw as simple machines. By the time of the Renaissance this list increased to include the wheel and axle and inclined plane; the modern approach to characterizing machines focusses on the components that allow movement, known as joints. Wedge: Perhaps the first example of a device designed to manage power is the hand axe called biface and Olorgesailie. A hand axe is made by chipping stone flint, to form a bifacial edge, or wedge. A wedge is a simple machine that transforms lateral force and movement o
A thermal oxidizer is a process unit for air pollution control in many chemical plants that decomposes hazardous gases at a high temperature and releases them into the atmosphere. Thermal oxidizers are used to destroy hazardous air pollutants and volatile organic compounds from industrial air streams; these pollutants are hydrocarbon based and when destroyed via thermal combustion they are chemically oxidized to form CO2 and H2O. Three main factors in designing the effective thermal oxidizers are temperature, residence time, turbulence; the temperature needs to be high enough to ignite the waste gas. Most organic compounds ignite at the temperature between 590 °C and 650 °C. To ensure near destruction of hazardous gases, most basic oxidizers are operated at much higher temperature levels; when catalyst is used, the operating temperature range may be lower. Residence time is to ensure; the turbulence factor is the mixture of combustion air with the hazardous gases. The simplest technology of thermal oxidation is direct-fired thermal oxidizer.
A process stream with hazardous gases is introduced into a firing box through or near the burner and enough residence time is provided to get the desired destruction removal efficiency of the VOCs. Most direct-fired thermal oxidizers operate at temperature levels between 980 °C and 1,200 °C with air flow rates of 0.24 to 24 standard cubic meters per second. Called afterburners in the cases where the input gases come from a process where combustion is incomplete, these systems are the least capital intensive, can be integrated with downstream boilers and heat exchangers to optimize fuel efficiency. Thermal Oxidziers are best applied where there is a high concentration of VOCs to act as the fuel source for complete combustion at the targeted operating temperature. One of today’s most accepted air pollution control technologies across industry is a regenerative thermal oxidizer referred to as a RTO. RTOs use a ceramic bed, heated from a previous oxidation cycle to preheat the input gases to oxidize them.
The preheated gases enter a combustion chamber, heated by an external fuel source to reach the target oxidation temperature, in the range between 760 °C and 820 °C. The final temperature may be as high as 1,100 °C for applications; the air flow rates are 2.4 to 240 standard cubic meters per second. RTOs are versatile and efficient – thermal efficiency can reach 95%, they are used for abating solvent fumes, etc. from a wide range of industries. Regenerative Thermal Oxidizers are ideal in a range of low to high VOC concentrations up to 10 g/m3 solvent. There are many types Regenerative Thermal Oxidizer on the market with the capabitlity of 99.5+% Volatile Organic Compound oxidisation or destruction efficiency. The ceramic heat exchanger in the towers can be designed for thermal efficiencies as high as 97+%. Ventilation air methane thermal oxidizers are used to destroy methane in the exhaust air of underground coal mine shafts. Methane is a greenhouse gas and, when oxidized via thermal combustion, is chemically altered to form CO2 and H2O.
CO2 is 25 times less potent than methane when emitted into the atmosphere with regards to global warming. Concentrations of methane in mine ventilation exhaust air of coal and trona mines are dilute. VAMTOX units have a system of valves and dampers that direct the air flow across one or more ceramic filled bed. On start-up, the system preheats by raising the temperature of the heat exchanging ceramic material in the bed at or above the auto-oxidation temperature of methane 1,000 °C, at which time the preheating system is turned off and mine exhaust air is introduced; the methane-filled air reaches the preheated bed, releasing the heat from combustion. This heat is transferred back to the bed, thereby maintaining the temperature at or above what is necessary to support auto-thermal operation. A less used thermal oxidizer technology is a thermal recuperative oxidizer. Thermal recuperative oxidizers have a primary and/or secondary heat exchanger within the system. A primary heat exchanger preheats the incoming dirty air by recuperating heat from the exiting clean air.
This is done by a plate heat exchanger. As the incoming air passes on one side of the metal tube or plate, hot clean air from the combustion chamber passes on the other side of the tube or plate and heat is transferred to the incoming air through the process of conduction using the metal as the medium of heat transfer. In a secondary heat exchanger the same concept applies for heat transfer, but the air being heated by the outgoing clean process stream is being returned to another part of the plant – back to the process. Biomass, such as wood chips, can be used as the fuel for a thermal oxidizer; the biomass is gasified and the stream with hazardous gases is mixed with the biomassgas in a firing box. Sufficient turbulence, retention time, oxygen content and temperature will ensure destruction of the VOC's; such biomass fired thermal oxidizer has been installed at New Hampshire. The inlet concentrations are between 3000-10.000 ppm VOC. The outlet concentration of VOC are below 3 ppm, thus having a VOC destruction efficiency of 99.8%-99.9%.
In a flameless thermal oxidizer system waste gas, ambient air, auxiliary fuel are premixed prior to passing the combined gaseous mixture through a prehea