A chemical plant is industrial process plant that manufactures (or otherwise processes) chemicals, usually on a large scale. For other uses of this term see Industry (disambiguation An industry (from Latin industrius, "diligent industrious" Industrial processes are procedures involving chemical or mechanical steps to aid in the Manufacture of an item or items usually carried out on a very A factory (previously manufactory) or manufacturing plant is an industrial Building where workers manufacture goods A chemical substance is a Material with a definite chemical composition. The general objective of a chemical plant is to create new material wealth via the chemical or biological transformation and or separation of materials. [1] Chemical plants use special equipment, units, and technology in the processes. Other kinds of plants, such as polymer, pharmaceutical, food, and some beverage production facilities, power plants, oil refineries or other refineries, natural gas processing and biochemical plants, water and wastewater treatment, and pollution control equipment use many technologies which have similarities to chemical plant technology such as fluid systems. A power station (also referred to as generating station, power plant or powerhouse) is an industrial facility for the generation of An oil refinery is an industrial Process plant where Crude oil is processed and refined into more useful Petroleum products, such as Gasoline A refinery is composed of a group of Chemical engineering unit processes and Unit operations used for Refining certain materials or converting Natural gas processing plants or fractionators are used to purify the raw Natural gas extracted from underground gas fields and brought up to the surface by Water is a common Chemical substance that is essential for the survival of all known forms of Life. Distinguish from Wastwater (a lake in the Lake District in northwest England Pollution is the introduction of contaminants into an environment that causes instability disorder harm or discomfort to the physical systems or living organisms they are in Some would consider an oil refinery or a pharmaceutical or polymer manufacturer to be effectively a chemical plant.
Petrochemical plants (plants using petroleum as a raw material) are usually located adjacent to an oil refinery to minimize transportation costs for the feedstocks produced by the refinery. Petrochemicals are chemical products made from raw materials of Petroleum or other Hydrocarbon origin An oil refinery is an industrial Process plant where Crude oil is processed and refined into more useful Petroleum products, such as Gasoline In Mathematics, the term optimization, or mathematical programming, refers to the study of problems in which one seeks to minimize or maximize a real function Transport or transportation is the movement of people and goods from one place to another Specialty chemical plants are usually much smaller and not as sensitive to location. A Specialty chemical is a Chemical produced for a Specialized use
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Chemical processes
Chemical plants are facilities constructed at certain locations which typically use chemical processes, which are detailed industrial-scale methods, to produce the chemicals. In a " scientific " sense a chemical process is a method or means of somehow changing one or more Chemicals or Chemical compounds Such a chemical The same chemical process can be used at more than one chemical plant, with possibly differently scaled capacities at each plant. Also, a chemical plant at a site may be constructed to utilize more than one chemical process.
A chemical plant commonly has usually large vessels or sections called units that are interconnected by piping or other material-moving equipment which can carry streams of material. For other uses see Pipe. Within Industry, piping is a system of pipes used to convey Fluids ( Liquids and Such material streams can include fluids (gas or liquid carried in piping) or sometimes solids or mixtures such as slurries. FLUID ( F ast L ight '''U'''ser '''I'''nterface D esigner is a graphical editor that is used to produce FLTK Source code This page is about the physical properties of gas as a state of matter Liquid is one of the principal States of matter. A liquid is a Fluid that has the particles loose and can freely form a distinct surface at the boundaries of A solid' object is in the States of matter characterized by resistance to Deformation and changes of Volume. An overall chemical process is commonly made up of steps called unit operations which occur in the individual units. In Chemical engineering and related fields a unit operation is a basic step in a Process. A raw material going into a chemical process or plant as input to be converted into a product is commonly called a feedstock, or simply feed. In addition to feedstocks for the plant as a whole, an input stream of material to be processed in a particular unit can similarly be considered feed for that unit. Output streams from the plant as a whole are final products and output streams from individual units may be considered intermediate products for their units. However, final products from one plant may be intermediate chemicals used as feedstock in another plant for further processing. For example, some products from an oil refinery may used as feedstock in petrochemical plants.
Either the feedstock(s), the product(s), or both may be individual compounds or mixtures. A chemical compound is a substance consisting of two or more different elements chemically bonded together in a fixed proportion by Mass. It is often not worthwhile separating the components in these mixtures completely based on product requirements and economics.
Continuous and batch operation
Chemical processes may be run in continuous or batch operation. In batch operation, production occurs in time-sequential steps in batches. A batch of feedstock(s) is fed into a process or unit, then the chemical process takes place, then the product(s) and any other outputs are removed. Such batch production may be repeated over again and again with new batches of feedstock. Batch operation is commonly used in smaller scale plants such as pharmaceutical or specialty chemicals production.
In continuous operation, all steps are ongoing continuously in time. During usual continuous operation, the feeding and product removal are ongoing streams of moving material, which together with the process itself, all take place simultaneously and continuously. Chemical plants or units in continuous operation are usually in a steady state or approximate steady state. Steady state is a more general situation than Dynamic equilibrium. Steady state means that quantities related to the process do not change as time passes during operation. Such constant quantities include stream flow rates, heating or cooling rates, temperatures, pressures, and chemical compositions at every point (location). The volumetric flow rate in Fluid dynamics and Hydrometry, (also known as volume flow rate or rate of fluid flow) is the volume of fluid which Temperature is a physical property of a system that underlies the common notions of hot and cold something that is hotter generally has the greater temperature Pressure (symbol 'p' is the force per unit Area applied to an object in a direction perpendicular to the surface Continuous operation is more efficient in many large scale operations like petroleum refineries. It is possible for some units to operate continuously and others be in batch operation in a chemical plant; for example, see Continuous distillation and Batch distillation. Continuous distillation, a form of Distillation, is an ongoing separation in which a mixture is continuously (without interruption fed into the process and separated fractions Batch distillation refers to the use of Distillation in batches meaning that a mixture is distilled to separate it into its component fractions before the distillation still The amount of primary feedstock or product per unit of time which a plant or unit can process is referred to as the capacity of that plant or unit. For examples: the capacity of an oil refinery may be given in terms of barrels of crude oil refined per day; alternatively chemical plant capacity may be given in tons of product produced per day. A barrel or cask is a hollow cylindrical container traditionally made of Wood Staves and bound with Iron Hoops The Petroleum ( L petroleum, from Greek πετρέλαιον, lit Units of mass There are three similar units of Mass called the ton: Long ton (simply ton in countries such as the United In actual daily operation, a plant (or unit) will operate at a percentage of its full capacity.
Units and fluid systems
Various kinds of unit operations are conducted in various kinds of units. In Chemical engineering and related fields a unit operation is a basic step in a Process. Although some units may operate at ambient temperature or pressure, many units operate at higher or lower temperatures or pressures. Vessels in chemical plants are often cylindrical with rounded ends, a shape which can be suited to hold either high pressure or vacuum. A cylinder is one of the most basic curvilinear geometric shapes the Surface formed by the points at a fixed distance from a given Straight line, the axis This vacuum means "absence of matter" or "an empty area or space" for the cleaning appliance see Vacuum cleaner. Chemical reactions can convert certain kinds of compounds into other compounds in chemical reactors. A chemical reaction is a process that always results in the interconversion of Chemical substances The substance or substances initially involved in a chemical reaction are called A chemical compound is a substance consisting of two or more different elements chemically bonded together in a fixed proportion by Mass. In Chemical engineering, chemical reactors are vessels designed to contain Chemical reactions The design of a chemical reactor deals with multiple aspects of Chemical reactors may be packed beds and may have solid heterogeneous catalysts which stay in the reactors as fluids move through. In Chemical processing a packed bed is a hollow tube, pipe or other vessel that is filled with a packing material Catalysis is the process in which the rate of a Chemical reaction is increased by means of a Chemical substance known as a catalyst Since the surface of solid heterogeneous catalysts may sometimes become poisoned from deposits such as coke, regeneration of catalysts may be necessary. Coke is a solid Carbonaceous material derived from Destructive distillation of low-ash low-sulfur Bituminous coal. Fluidized beds may also be used in some cases. A fluidized bed is formed when a quantity of a Solid particulate substance (usually present in a holding vessel is placed under appropriate conditions to cause the solid/fluid There can also be units (or subunits) for mixing (including dissolving), separation, heating, cooling, or some combination of these. In industrial Process engineering, mixing is a Unit operation that involves manipulating a Heterogeneous physical system with the intent to make it In Chemistry and Chemical engineering, a separation process is used to transform a Mixture of substances into two or more distinct products For example, chemical reactors often have stirring for mixing and heating or cooling going on in them. When designing plants on a large scale, heat produced or absorbed by chemical reactions should be considered. The standard enthalpy change of reaction (denoted ΔH ° or ΔH o is the Enthalpy change that occurs in a system when one mole of matter Some plants may have units with organism cultures for biochemical processes such as fermentation or enzyme production. Fermentation has many important uses in industry Though the word fermentation can have stricter definitions when speaking of it in industrial fermentation it more loosely Enzymes are Biomolecules that catalyze ( ie increase the rates of Chemical reactions Almost all enzymes are Proteins
Separation processes include filtration, settling (sedimentation), extraction or leaching, distillation, recrystallization or precipitation (followed by filtration or settling), reverse osmosis, drying, and adsorption. In Chemistry and Chemical engineering, a separation process is used to transform a Mixture of substances into two or more distinct products Filtration is a mechanical or physical operation which is used for the separation of solids from fluids (liquids or gases by interposing a medium to fluid flow through which the fluid Settling is the process by which particulates settle to the bottom of a liquid and form a Sediment. Liquid-liquid extraction, also known as solvent extraction and partitioning, is a method to separate compounds based on their relative solubilities in two Distillation is a method of separating Mixtures based on differences in their volatilities in a boiling liquid mixture Recrystallization (see also Crystallization) is a physical process that has meanings in Chemistry, Metallurgy and Geology. Precipitation is the formation of a Solid in a Solution during a Chemical reaction. Reverse osmosis (RO is a separation process that uses pressure to force a Solution through a membrane that retains the Solute on one side and allows the Drying is a Mass transfer process resulting in the removal of water Moisture or moisture from another Solvent, by Evaporation from a Solid Adsorption is a process that occurs when a gas or liquid Solute accumulates on the surface of a solid or a liquid (adsorbent forming a film of molecules or atoms (the Heat exchangers are often used for heating or cooling, including boiling or condensation, often in conjunction with other units such as distillation towers. A heat exchanger is a device built for efficient Heat transfer from one medium to another whether the media are separated by a solid wall so that they never mix or the media Boiling (also called ebullition) a type of Phase transition, is the rapid vaporization of a Liquid, which typically occurs when a liquid Condensation is the change of the physical state of aggregation (or simply state of matter from gaseous phase into liquid phase There may also be storage tanks for storing feedstock, intermediate or final products, or waste. Chemical tanks are storage Containers for Chemicals They come in a variety of sizes and shapes and are used for Static storage mixing and transport Storage tanks commonly have level indicators to show how full they are. There may be structures holding or supporting sometimes massive units and their associated equipment. There are often stairs, ladders, or other steps for personnel to reach points in the units for sampling, inspection, or maintenance.
Fluid systems for carrying liquids and gases include piping and tubing of various diameter sizes, various types of valves for controlling or stopping flow, pumps for moving or pressurizing liquid, and compressors for pressurizing or moving gases. For other uses see Valve (disambiguation. For the electronic component see Thermionic valve. For information on Wikipedia project-related discussions see WikipediaVillage pump. A gas compressor is a mechanical device that increases the Pressure of a Gas by reducing its Volume. Vessels, piping, tubing, and sometimes other equipment at high or very low temperature are commonly covered with insulation for personnel safety and to maintain temperature inside. The term thermal insulation can refer to materials used to reduce the rate of Heat transfer, or the methods and processes used to reduce heat transfer Fluid systems and units commonly have instrumentation such as temperature and pressure sensors and flow measuring devices at select locations in a plant. Instrumentation is the branch of science that deals with measurement and control in order to increase efficiency and safety in the workplace Flow measurement is the quantification of bulk Fluid movement Online analyzers for chemical or physical property analysis have become more common. An analyser, also spelt analyzer, is a device that analyses given data Solvents can sometimes be used to dissolve reactants or materials such as solids for extraction or leaching, to provide a suitable medium for certain chemical reactions to run, or so they can otherwise be treated as fluids. A solvent is a liquid or gas that dissolves a solid liquid or gaseous Solute, resulting in a Solution. A reagent or reactant is a substance or compound consumed during a Chemical reaction.
Chemical plant design
The fundamental aspects of designing chemical plants are done by chemical engineers. An oil refinery is an industrial Process plant where Crude oil is processed and refined into more useful Petroleum products, such as Gasoline Design is used both as a Noun and a Verb. The term is often tied to the various Applied arts and Engineering (See design disciplines In the field of Engineering, a chemical engineer is the profession in which one works principally in the Chemical industry to convert basic raw materials into a variety In plant design, typically less than 1% of ideas for new designs ever become commercialized. During this solution process, typically, cost studies are used as an initial screening to eliminate unprofitable designs. If a process appears profitable, then other factors are considered, such as safety, environmental constraints, controllability, etc. [1] The general goal in plant design, is to construct or synthesize “optimum designs” in the neighborhood of the desired constraints.
Many times chemists research chemical reactions or other chemical principles in a laboratory, commonly on a small scale in a "batch-type" experiment. A chemist is a Scientist trained in the Science of Chemistry. A laboratory (informally lab) is a facility that provides controlled conditions in which scientific Research, Experiments and Chemistry information obtained is then used by chemical engineers, along with expertise of their own, to convert to a chemical process and scale up the batch size or capacity. Commonly, a small chemical plant called a pilot plant is built to provide design and operating information before construction of a large plant. A pilot plant is a small chemical processing system which is operated to generate information about the behavior of the system for use in Design of larger facilities From data and operating experience obtained from the pilot plant, a scaled-up plant can be designed for higher or full capacity. After the fundamental aspects of a plant design are determined, mechanical or electrical engineers may become involved with mechanical or electrical details, respectively. Mechanical Engineering is an Engineering discipline that involves the application of principles of physics for analysis Design, Manufacturing Electrical engineering, sometimes referred to as electrical and electronic engineering, is a field of Engineering that deals with the study and application of Structural engineers may become involved in the plant design to ensure the structures can support the weight of the units, piping, and other equipment. Structural engineers analyze design plan and research structural components and Structural systems Their work takes account mainly of technical economic and environmental In the Physical sciences weight is a Measurement of the gravitational Force acting on an object
The units, streams, and fluid systems of chemical plants or processes can be represented by block flow diagrams which are very simplified diagrams, or process flow diagrams which are somewhat more detailed. Block diagram is a Diagram of a System, in which the principal parts or functions are represented by blocks connected by lines that show the relationships of A process flow diagram (PFD is a diagram commonly used in chemical and Process engineering to indicate the general flow of plant processes and equipment The streams and other piping are shown as lines with arrow heads showing usual direction of material flow. In block diagrams, units are often simply shown as blocks. Process flow diagrams may use more detailed symbols and show pumps, compressors, and major valves. Likely values or ranges of material flow rates for the various streams are determined based on desired plant capacity using material balance calculations. Energy balances are also done based on heats of reaction, heat capacities, expected temperatures and pressures at various points to calculate amounts of heating and cooling needed in various places and to size heat exchangers. The standard enthalpy change of reaction (denoted ΔH ° or ΔH o is the Enthalpy change that occurs in a system when one mole of matter Specific heat capacity, also known simply as specific heat, is the measure of the heat energy required to increase the Temperature of a unit quantity Chemical plant design can be shown in fuller detail in a piping and instrumentation diagram (P&ID) which shows all piping, tubing, valves, and instrumentation, typically with special symbols. A piping and instrumentation diagram/drawing (P&ID is defined by the Institute of Instrumentation and Control as follows A diagram which shows the interconnection Showing a full plant is often complicated in a P&ID, so often only individual units or specific fluid systems are shown in a single P&ID.
In the plant design, the units are sized for the maximum capacity each may have to handle. Similarly, sizes for pipes, pumps, compressors, and associated equipment are chosen for the flow capacity they have to handle. Utility systems such as electric power and water supply should also be included in the plant design. Electric power is defined as the rate at which Electrical energy is transferred by an Electric circuit. Water is a common Chemical substance that is essential for the survival of all known forms of Life. Additional piping lines for non-routine or alternate operating procedures, such as plant or unit startups and shutdowns, may have to be included. Fluid systems design commonly includes isolation valves around various units or parts of a plant so that a section of a plant could be isolated in case of a problem such as a leak in a unit. LEAK is the brand name for high-fidelity audio equipment made by H If pneumatically or hydraulically actuated valves are used, a system of pressurizing lines to the actuators are needed. Any points where process samples may have to be taken should have sampling lines, valves, and access to them included in the detailed design. If necessary, provisions should be made for reducing high pressure or temperature of a sampling stream, such including a pressure reducing valve or sample cooler.
Units and fluid systems in the plant including all vessels, piping, tubing, valves, pumps, compressors, and other equipment must be rated or designed to be able to withstand the entire range of pressures, temperatures, and other conditions which they could possibly encounter, including any appropriate safety factors. Factor of safety ( FoS) can mean either the fraction of structural capability over that required or a Multiplier applied to the maximum expected load ( Force All such units and equipment should also be checked for materials compatibility to ensure they can withstand long-term exposure to the chemicals they will come in contact with. Chemical compatibility is a measure of how stable a Substance is when mixed with another substance Any closed system in a plant which has a means of pressurizing possibly beyond the rating of its equipment, such as heating, exothermic reactions, or certain pumps or compressors, should have an appropriately sized pressure relief valve included to prevent overpressurization for safety. The relief valve is a type of Valve used to control or limit the Pressure in a system or vessel which can build up by a process upset instrument or equipment failure Frequently all of these parameters (temperatures, pressures, flow, etc. ) are exhaustively analyzed in combination through a Hazop or fault tree analysis, to ensure that the plant has no known risk of serious hazard. Fault tree analysis (FTA is a failure analysis in which an undesired state of a system is analyzed using Boolean logic to combine a series of lower-level events
Within any constraints the plant is subject to, design parameters are optimized for good economic performance while ensuring safety and welfare of personnel and the surrounding community. Process optimization is the discipline of adjusting a process so as to optimize some specified set of parameters without violating some constraint For flexibility, a plant may be designed to operate in a range around some optimal design parameters in case feedstock or economic conditions change and re-optimization is desirable. In more modern times, computer simulations or other computer calculations have been used to help in chemical plant design or optimization. A computer simulation, a computer model or a computational model is a Computer program, or network of computers that attempts to simulate an
Plant operation
Process control
In process control, information gathered automatically from various sensors or other devices in the plant is used to control various equipment for running the plant, thereby controlling operation of the plant. Process control is a Statistics and Engineering discipline that deals with Architectures mechanisms and Algorithms for controlling Instruments receiving such information signals and sending out control signals to perform this function automatically are process controllers. In Control theory, a controller is a device which monitors and affects the operational conditions of a given Dynamical system. Previously, pneumatic controls were sometimes used. Pneumatics, Pressurized gas to affect mechanical motion Pneumatic power is used in Industry, where it is common to have factory units plumbed for Compressed Electrical controls are now common. A plant often has a control room with displays of parameters such as key temperatures, pressures, fluid flow rates and levels, operating positions of key valves, pumps and other equipment, etc. A control room is a room serving as an operations centre where a facility or service can be monitored and controlled In addition, operators in the control room can control various aspects of the plant operation, often including overriding automatic control. Process control with a computer represents more modern technology. Based on possible changing feedstock composition, changing products requirements or economics, or other changes in constraints, operating conditions may be re-optimized to maximize profit.
Workers
As in any industrial setting, there are a variety of workers working throughout a chemical plant facility, often organized into departments, sections, or other work groups. Such workers typically include engineers, plant operators, and maintenance technicians. An engineer is a person professionally engaged in a field of Engineering. A plant operator is a person who supervises the operation of an Industrial plant. Other personnel at the site could include chemists, management/administration and office workers. Types of engineers involved in operations or maintenance may include chemical process engineers, mechanical engineers for maintaining mechanical equipment, and electrical/computer engineers for electrical or computer equipment. A computer is a Machine that manipulates data according to a list of instructions.
Transport
Large quantities of fluid feedstock or product may enter or leave a plant by pipeline, railroad tank car, or tanker truck. Pipeline transport is the transportation of goods through a pipe. For Jay Leno's bespoke Tank -engined car see the Blastolene Special. A tank truck ( United States usage or tanker lorry ( United Kingdom usage is a Motor vehicle designed to carry liquefied loads, For example, petroleum commonly comes to a refinery by pipeline. Pipelines can also carry petrochemical feedstock from a refinery to a nearby petrochemical plant. Natural gas is a product which comes all the way from a natural gas processing plant to final consumers by pipeline or tubing. Natural gas is a Gaseous Fossil fuel consisting primarily of Methane but including significant quantities of Ethane, Propane, Large quantities of liquid feedstock are typically pumped into process units. Smaller quantities of feedstock or product may be shipped to or from a plant in drums. A drum is a cylindrical container used for shipping bulk goods Use of drums about 55 gallons in capacity is common for packaging industrial quantities of chemicals. Packaging is the science art and technology of enclosing or protecting products for distribution storage sale and use Smaller batches of feedstock may be added from drums or other containers to process units by workers.
Maintenance
In addition to feeding and operating the plant, and packaging or preparing the product for shipping, plant workers are needed for taking samples for routine and troubleshooting analysis and for performing routine and non-routine maintenance. Routine maintenance can include periodic inspections and replacement of worn catalyst, analyzer reagents, various sensors, or mechanical parts. Non-routine maintenance can include investigating problems and then fixing them, such as leaks, failure to meet feed or product specifications, mechanical failures of valves, pumps, compressors, sensors, etc.
Regulatory compliance
When working with chemicals, safety is a concern. Safety is the state of being "safe" (from French sauf) the condition of being protected against physical social spiritual financial political In the United States, the law requires that employers provide workers working with chemicals with access to a Material Safety Data Sheet (MSDS) for every kind of chemical they work with. The United States of America —commonly referred to as the A material safety data sheet ( MSDS) is a form containing data regarding the properties of a particular substance An MSDS for a certain chemical is prepared and provided by the supplier to whomever buys the chemical. Other laws covering chemical safety, hazardous waste, and pollution must be observed such as the Resource Conservation and Recovery Act (RCRA) and the Toxic Substances Control Act (TSCA) in the United States. The Resource Conservation and Recovery Act (RCRA enacted in 1976, is a Federal law of the United States contained in 42 U The Toxic Substances Control Act ( TSCA) is a United States law passed by the United States Congress in 1976, that regulates the introduction Hazmat (hazardous materials) teams are trained to deal with chemical leaks or spills.
Plant facilities
The actual production or process part of a plant may be indoors, outdoors, or a combination of the two. The actual production section of a facility usually has the appearance of a rather industrial environment. Hard hats and work shoes are commonly worn. Floors and stairs are often made of metal grating, and there is practically no decoration. There may also be pollution control or waste treatment facilities or equipment. Pollution is the introduction of contaminants into an environment that causes instability disorder harm or discomfort to the physical systems or living organisms they are in Waste treatment refers to the activities required to ensure that Waste has the least practicable impact on the environment Sometimes existing plants may be expanded or modified based on changing economics, feedstock, or product needs. As in other production facilities, there may be shipping and receiving, and storage facilities. A warehouse is a commercial Building for Storage of Goods. Warehouses are used by Manufacturers Importers Exporters In addition, there are usually certain other facilities, typically indoors, to support production at the site.
Although some simple sample analysis may be able to be done by operations technicians in the plant area, a chemical plant typically has a laboratory where chemists analyze samples taken from the plant. A laboratory (informally lab) is a facility that provides controlled conditions in which scientific Research, Experiments and Such analysis can include chemical analysis or determination of physical properties. Analytical chemistry is the study of the Chemical composition of natural and artificial Materials. Sample analysis can include routine quality control on feedstock coming into the plant, intermediate and final products to ensure quality specifications are met. In Engineering and Manufacturing, quality control and quality engineering are involved in developing systems to ensure products or services Non-routine samples may be taken and analyzed for investigating plant process problems also. A larger chemical company often has a research laboratory for developing and testing products and processes where there may be pilot plants, but such a laboratory may be located at a site separate from the production plants. The chemical industry comprises the companies that produce industrial chemicals
A plant may also have a workshop or maintenance facility for repairs or keeping maintenance equipment. There is also typically some office space for engineers, management or administration, and perhaps for receiving visitors. The decorum there is commonly more typical of an office environment.
See also
- Chemical industry ("Chemical company" redirects to "Chemical industry". The chemical industry comprises the companies that produce industrial chemicals )
- Chemical process modeling
References
- ^ a b Douglas, James M. Chemical process modeling is a Computer modeling technique used in Chemical engineering process design. (1988). Conceptual Design of Chemical Processes. McGraw-Hill. ISBN 0070177627.
Dictionary
chemical plant
-noun
- (chemistry) an industrial facility used to manufacture chemical compounds
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