Using Industrial Hydraulics |
Applications of Computer-Aided Manufacturing
are employed in a variety of interrelated and interdependent industries and companies in which one concern often makes chemical precursors or starting materials for another’s use.Most chemical workers convert the starting products or raw materials into other chemical com pounds and derivative products, such as pharmaceuticals, plastics, solvents, and paints. In addition to being actively engaged in chemical operations, some workers are required to maintain safety, health, and environmental standards mandated by the federal government and perform routine and preventive maintenance tasks. Still others handle, store, and transport chemicals and operate batch processes.
Although its origins can be traced back to ancient Greece, chemistry was recognized as a physical science during the 17th century. The alkali industry, which began then, made alkalis (caustic com pounds such as sodium or potassium hydroxide) and alkaline salts such as soda ash (sodium carbonate) from wood and plant ashes. These compounds were then used to make soap and glass. By 1775, the natural sources of these alkaline compounds could not meet demand. Encouraged by the French Academy of Sciences, Nicholas Leblanc devised a synthetic process to manufacture them cheaply. Large-scale use of his process came a few years later in En gland. Inspired and encouraged by Leblanc’s success, other scientists developed new methods for making a variety of industrially important chemicals. This marked the beginning of the modern industrial chemicals industry. In the 1880s, the Leblanc process was superseded by the Solvay process. In the industrial chemical field today, many compounds, such as ethylene, which is derived from petroleum, are used to synthesize countless other useful products. Ethylene can be used to make polyethylene, polyethylene terephthalate, polystyrene, vinyl plastics, ethyl alcohol, and ethyl ether, to name just a few. Many of these, in turn, are used in fibers, fabrics, paints, resins, fuels, and pharmaceuticals. Thus, it is evident how one industry feeds off and relies on another. New uses for chemicals continue to be found, as well as new compounds to be synthesized. Some of these compounds will eventually supplant those now in use.
Workers in industrial chemicals plants make all the products previously mentioned plus thousands more. Basic chemicals such as sulfuric acid, nitric acid, hydrochloric acid, sodium hydroxide, sodium chloride, and ammonia are made by giant companies. The demand for these products is so great that only large companies can afford to build the factories and buy the equipment and the raw materials to produce these chemicals at the low prices for which they sell them. On the other hand, these giant companies rarely make specialty chemicals because they either can’t afford to or they don’t wish to make the necessary investment due to the very limited market. Those products are made by small companies.
Because of the large variety of chemicals produced and the number of different processes involved, there are hundreds of job categories. Many of the jobs have quite a bit in common. In general, workers measure batches according to formulas; set reaction parameters for temperature, pressure, or flow of materials; and read gauges to monitor processes. They do routine testing, keep records, and may write progress reports. Many operators use computerized control panels to monitor processes. Some operate mixing machines, agitator tanks, blenders, steam cookers, and other equipment. The worker may pour two or more raw ingredients from storage vats into a reaction vessel or empty cars from overhead conveyors, dumping the contents of a barrel or drum, or manually transfer materials from a hopper, box, or other container. The worker measures a preset amount of ingredients and then activates the mixing machine, while keeping an eye on the gauges and controls.
When the mixture has reached the desired consistency, color, or other characteristic, a test sample may be removed. If the analysis is satisfactory, the mixture is moved to its next destination either by piping, pumping into another container or processing machine, emptying into drums or vats, or by a conveyor. The operator then records the amount and condition of the mixture and readies his equipment for the next run.
Other workers may separate contaminants, undesirable by products, and unreacted materials with equipment that filters, strains, sifts, or centrifuges. Filters and centrifuges are often used to separate a slurry into liquid and solid parts. The filter-press operator sets up the press by covering the filter plates with canvas or paper sheets that separate the solids from the liquid portion. After the filtration, the plates are removed and cleaned. The centrifuge is a machine that spins a solid-liquid mixture like a washing machine in the spin cycle to separate it into solid and liquid components. If the desired end product is the liquid, the centrifuge operator discards the solids, and vice versa.
Distillation operators use equipment that separates liquid mixtures by first heating them to their boiling points. The heated vapors rise into a distillation column. If a very pure liquid is desired, a fractional distillation column is used. A distillation apparatus consists of an electrically or steam-heated still pot, a distillation column, a water-cooled condenser, and a collector. In this process, the hot vapors rise through the distillation column. The condenser cools the vapors and converts them back into a liquid. The condensed liquid is collected and removed for further use. Distillation, a very important separation technique for purifying and separating liquids, is widely used in the liquor industry, petroleum refineries, and chemical companies that make and use liquid chemicals.
Solid chemical mixtures often need to be dried before they can be used. Workers heat, bake, dry, and melt chemicals with kilns, vacuum dryers, rotary or tunnel furnaces, and spray dryers. The workers who operate this equipment, regardless of the industry, perform the same operations.
The paint industry manufactures paints, varnishes, shellacs, lacquers, and a variety of liquid products for decorative and protective coatings. It not only makes many of the materials that go into its products but also purchases chemicals, resins, solvents, dyes, and pigments from others. In its operations, it performs many of the same tasks as those described. Coating and laminating are related industries. Their workers operate press rollers; laminating, coating, and printing machines; and sprayers. They carefully apply measured thicknesses of coating materials to a variety of substrates, such as paper, plastic, metal, and fabric.
Example: Art often test pigments at a manufacturing plant.
Most of the equipment in the industrial chemicals industry is now automated and computer controlled. Because of the complex equipment used, employers prefer to hire workers with at least a high school diploma. Knowledge of basic mathematics, science, and computer skills is essential for those seeking employment in this field. Machine shop experience is also useful.
Entry-level employees always get on-the-job training and special classroom work. Classes may include heat transfer principles, the basics of distillation, how to take readings on tanks and other equipment, and how to read blueprints. Workers also get safety training about the chemicals and processes they will encounter.
More advanced knowledge of chemistry and physics is important for those who hope to advance to supervisory and managerial positions. Training to become a skilled operator may take two to five years. Information on apprenticeship programs can be found through state employment bureaus. Some community colleges offer programs that allow students to combine classroom work with on- the-job experience to enhance their skills and knowledge.
Workers in this industry must be dependable, alert, accurate, and able to follow instructions exactly. They must always be mindful of the potential hazards involved in working with chemicals and cannot ever be careless. They should be conscientious, able to work without direct supervision, willing to do repetitive and sometimes monotonous work, and be able to work well with others.
A helpful and inexpensive way to explore employment opportunities is to talk with someone who has worked in the industry in which you are interested. Also, it may be possible to arrange a tour of a manufacturing plant by contacting its public relations department. Another way to explore chemical manufacturing occupations is to check high school or public libraries for books on the industry. Other sources include trade journals, high school guidance counselors, and university career services offices. You should join your high school or college science clubs. You can also subscribe to the American Chemical Society’s ChemMatters, a quarterly magazine for high school chemistry students. (To read the magazine online, visit the society’s Web site, http://www.chemistry.org/portal/a/c/s/l/home.html, and click “Educators and Students.”)
are a necessary part of all chemical manufacturing whether the industry is producing basic chemicals, pharmaceuticals, paints, food, or a myriad of other products. The companies that employ them vary in size, depending on the nature of the products they produce. Some large industrial chemicals companies (DuPont and Dow Chemical Company, for example) may make the chemicals they use in their own operations. Others purchase what they need from specialty chemical companies, such as Mallinckrodt Baker.
Basic chemicals, such as sodium hydroxide and nitric acid, are usually made by giant companies while small companies may make fine or specialty chemicals to supply to other manufacturers. Some workers are involved in the actual production process; others focus on the equipment used in manufacturing; still others test finished products to ensure that they meet industry and government standards of purity and safety. There are a number of government laboratories, such as the Department of Agriculture and the National Institute of Standards and Technology, that employ chemical workers.
High school graduates qualify for entry-level factory jobs as helpers, laborers, and material movers. They learn how to handle chemicals safely and acquire skills that enable them to advance to higher levels of responsibility. Students interested in a job in the industrial chemicals industry should look for information on job openings through classified ads and employment agencies. Information can also be obtained by contacting the personnel offices of individual chemical plants and local union offices of the International Chemical Workers Union and the United Steel, Paper and Forestry, Rubber, Manufacturing, Energy, Allied-Industrial and Service Workers International Union (more commonly known as the United Steelworkers of America). High school and college guidance and career services offices are other knowledgeable sources.
Movement into higher paying jobs is possible with increased experience and on-the-job training. Advancement usually requires mastery of advanced skills. Employers often offer classes for those who want to improve their skills and advance their careers.
Most workers start as laborers or unskilled helpers. They can advance to mechanic and installer jobs through formal vocational or in-house training. Or they can move up to positions as skilled operators of complex processes. They may become operators who monitor the flow and mix ratio of chemicals as they go through the production process. Experienced and well-trained production workers can advance to become supervisors overseeing an entire process.
In 2005, median annual earnings for chemical equipment operators and tenders were $39,030, according to the U.S. Department of Labor. Chemical plant and system operators earned median annual salaries of $46,710, while mixing and blending machine setters, operators, and tenders averaged $28,890. Managers and supervisors earn salaries that range from $50,000 to $60,000 or higher, depending on job duties and the number of workers that they supervise. Workers are usually paid more for night, weekend, and overtime work. Hourly rates for each production job are often set by union contract. Fringe benefits vary among employers. They may include group, hospital, dental, and life insurance; paid holidays and vacations; and pension plans. Also, many workers qualify for college tuition aid from their companies.
Working conditions in plants vary, depending on specific jobs, the type and condition of the equipment used, and the size and age of the plant. Chemical processing jobs used to be very dangerous, dirty, and disagreeable. However, working conditions have steadily improved over the years as a result of environmental, safety, and health standards mandated by the government. As a result of government intervention, chemical manufacturing now has an excellent safety record that is superior to other manufacturing industries. Nevertheless, chemical plants by their very nature can be extremely hazardous if strict safety procedures are not followed and enforced. Precautions include wearing protective clothing and equipment where required. Hard hats and safety goggles are worn throughout the plant.
Although few jobs in this industry are strenuous, they may become monotonous. Since manufacturing is a continuous process, most chemical plants operate around the clock. Once a process has begun, it cannot be stopped. This means that workers are needed for three shifts; split, weekend, and night shifts are common.
While the output and productivity of the industrial chemicals industry is expected to increase, the U.S. Department of Labor predicts that employment for will decline through 2014. More efficient production processes, increased plant automation, and growing competition with overseas chemical manufacturers will limit job growth for production workers in this industry.
Advancing technology should create jobs for technical workers with the necessary skills to handle increasingly complex chemical processes and controls, as well as jobs for computer specialists who have technical expertise in computer-controlled production.
FOR MORE INFORMATION
To subscribe to ChemMatters or to learn more about chemical process industries and technical operators, contact
American Chemical Society
1155 16th Street, NW
Washington, DC 20036-4801
The American Chemistry Council offers a great deal of information about the chemical industry and maintains an informative Web site.
American Chemistry Council
1300 Wilson Boulevard
Arlington VA 22209-2323
For information on chemical engineering, contact:
American Institute of Chemical Engineers
3 Park Avenue
New York, NY 10016-5991