A by-product, or byproduct, is a secondary product derived from a manufacturing process or chemical reaction. It is not the primary product or service being produced. In the context of production, a by-product is the 'output from a joint production process that is minor in quantity and/or net realizable value (NRV) when compared with the main products'.[1] Because they are deemed to have no influence on reported financial results, by-products do not receive allocations of joint costs. By-products also by convention are not inventoried, but the NRV from by-products is typically recognized as 'other income' or as a reduction of joint production processing costs when the by-product is produced.[2] A by-product can be useful and marketable or it can be considered waste. For example, bran is a byproduct of the milling of refined flour, sometimes composted or burned for disposal but in other cases used as a nutritious ingredient in food or feed, and gasoline was once a byproduct of oil refining that later became a desirable commodity as motor fuel.

IEA defines "by-product" in the context of life-cycle assessment: "... main products, co-products (which involve similar revenues to the main product), by-products (which result in smaller revenues), and waste products (which provide little or no revenue)."[3]

While some chemists treat "by-product" and "side-product" as synonyms in the above sense of a generic secondary (untargeted) product, others find it useful to distinguish the two. When the two terms are distinguished, "by-product" is used to refer to a product that is not desired but inevitably results from molecular fragments of starting materials and/or reagents that are not incorporated into the desired product, as a consequence of conservation of mass. In contrast, "side-product" is used to refer to a product that is formed from a competitive process that could, in principle, be suppressed by optimization of reaction conditions.

See also


  1. ^ Wouters, Mark; Selto, Frank H.; Hilton, Ronald W.; Maher, Michael W. (2012): Cost Management: Strategies for Business Decisions, International Edition, McGraw-Hill, p. 535.
  2. ^ World Trade Organization (2004): United States - Final dumping determination on softwood lumber from Canada, WT/DS264/AB/R, 11 August 2004.
  3. ^ "BIOMITRE Technical Manual, Horne, R. E. and Matthews, R., November 2004" (PDF). Archived from the original (PDF) on 2011-07-26. Retrieved 2011-02-16.
Animal product

An animal product is any material derived from the body of an animal. Examples are fat, flesh, blood, milk, eggs, and lesser known products, such as isinglass and rennet.Animal by-products, as defined by the USDA, are products harvested or manufactured from livestock other than muscle meat. In the EU, animal by-products (ABPs) are defined somewhat more broadly, as materials from animals that people do not consume. Thus, chicken eggs for human consumption are considered by-products in the US but not France; whereas eggs destined for animal feed are classified as animal by-products in both countries. This does not in itself reflect on the condition, safety, or "wholesomeness" of the product.

Animal by-products are carcasses and parts of carcasses from slaughterhouses, animal shelters, zoos and veterinarians, and products of animal origin not intended for human consumption, including catering waste. These products may go through a process known as "rendering" to be made into human and non-human foodstuffs, fats, and other material that can be sold to make commercial products such as cosmetics, paint, cleaners, polishes, glue, soap and ink. The sale of animal by-products allows the meat industry to compete economically with industries selling sources of vegetable protein.The word animals includes all species in the biological kingdom Animalia. For example, insects, shrimp, and oysters are animals.

Generally, products made from fossilized or decomposed animals, such as petroleum formed from the ancient remains of marine animals, are not considered animal products. Crops grown in soil fertilized with animal remains are rarely characterized as animal products.

Several diets prohibit the inclusion of some animal products, including vegetarian, kosher, and halal. Other diets, such as veganism and the raw vegan diet, exclude any material of animal origin.In international trade legislation, the terminology products of animal origin (POAO) is used.


Brine is a high-concentration solution of salt (usually sodium chloride) in water. In different contexts, brine may refer to salt solutions ranging from about 3.5% (a typical concentration of seawater, on the lower end of solutions used for brining foods) up to about 26% (a typical saturated solution, depending on temperature). Lower levels of concentration are called by different names: fresh water, brackish water, and saline water.

Brine naturally occurs on the Earth's surface (salt lakes), crust, and within brine pools on ocean bottom. High-concentration brine lakes typically emerge due to evaporation of ground saline water on high ambient temperatures. Brine is used for food processing and cooking (pickling and brining), for de-icing of roads and other structures, and in a number of technological processes. It is also a by-product of many industrial processes, such as desalination, and may pose an environmental risk due to its corrosive and toxic effects, so it requires wastewater treatment for proper disposal.

Bus manufacturing

Bus manufacturing, a sector of the automotive industry, manufactures buses and coaches.

Commercial bank

A commercial bank is a type of bank that provides services such as accepting deposits, making business loans, and offering basic investment products that is operated as a business for profit.

It can also refer to a bank, or a division of a large bank, which deals with corporations or large/middle-sized business to differentiate it from a retail bank and an investment bank.


Excretion is a process by which metabolic waste

is eliminated from an organism. In vertebrates this is primarily carried out by the lungs, kidneys and skin. This is in contrast with secretion, where the substance may have specific tasks after leaving the cell. Excretion is an essential process in all forms of life. For example, in mammals urine is expelled through the urethra, which is part of the excretory system. In unicellular organisms, waste products are discharged directly through the surface of the cell.

During life activities such as cellular respiration, several chemical reactions take place in the body. These are known as metabolism. These chemical reactions produce waste products such as carbon dioxide, water, salts, urea and uric acid. Accumulation of these wastes beyond a level inside the body is harmful to the body. The excretory organs remove these wastes. This process of removal of metabolic waste from the body is known as excretion.

Green plants produce carbon dioxide and water as respiratory products. In green plants, the carbon dioxide released during respiration gets utilized during photosynthesis. Oxygen is a by product generated during photosynthesis, and exits through stomata, root cell walls, and other routes. Plants can get rid of excess water by transpiration and guttation. It has been shown that the leaf acts as an 'excretophore' and, in addition to being a primary organ of photosynthesis, is also used as a method of excreting toxic wastes via diffusion. Other waste materials that are exuded by some plants — resin, saps, latex, etc. are forced from the interior of the plant by hydrostatic pressures inside the plant and by absorptive forces of plant cells. These latter processes do not need added energy, they act passively. However, during the pre-abscission phase, the metabolic levels of a leaf are high. Plants also excrete some waste substances into the soil around them.

In animals, the main excretory products are carbon dioxide, ammonia (in ammoniotelics), urea (in ureotelics), uric acid (in uricotelics), guanine (in Arachnida) and creatine. The liver and kidneys clear many substances from the blood (for example, in renal excretion), and the cleared substances are then excreted from the body in the urine and feces.

Aquatic animals usually excrete ammonia directly into the external environment, as this compound has high solubility and there is ample water available for dilution. In terrestrial animals ammonia-like compounds are converted into other nitrogenous materials as there is less water in the environment and ammonia itself is toxic.

Birds excrete their nitrogenous wastes as uric acid in the form of a paste. Although this process is metabolically more expensive, it allows more efficient water retention and it can be stored more easily in the egg. Many avian species, especially seabirds, can also excrete salt via specialized nasal salt glands, the saline solution leaving through nostrils in the beak.

In insects, a system involving Malpighian tubules is utilized to excrete metabolic waste. Metabolic waste diffuses or is actively transported into the tubule, which transports the wastes to the intestines. The metabolic waste is then released from the body along with fecal matter.

The excreted material may be called ejecta. In pathology the word ejecta is more commonly used.

Gold mining

Gold mining is the resource extraction of gold by mining.

List of countries by aircraft and spacecraft exports

The following is a list of countries by exports of aircraft, including helicopters, and spacecraft (Harmonized System code 8802). Data is for 2016, in billions of United States dollars, as reported by The Observatory of Economic Complexity. Currently the top twenty countries are listed.

Note: Export realized under secret code are not counted. The use of secret code is particularly frequent for military equipment, including military aircraft. Example: Russia exported 14 fighter aircraft Su-30 in the year 2016, as well as other types of military aircraft. Depending on sources, the Su-30 are sold at more or less 50 million USD per unit.

Pakistan PAC

List of countries by car exports

The following is a list of countries by car exports. Data is for 2017, in billions of United States dollars. Currently the top ten countries are listed.

List of countries by coffee exports

The following is a list of countries by coffee exports. Data is for 2012 & 2016, in millions of United States dollars, as reported by The Observatory of Economic Complexity. Currently the top twenty countries (as of 2016) are listed.

List of countries by exports

This is a list of countries by merchandise exports, based on The World Factbook of the CIA.

World Bank's World Integrated Trade Solution now provides list of countries and their share Top exporting countries

List of countries by natural gas exports

This is a list of countries by natural gas exports mostly based on The World Factbook [1]. For informational purposes several non-sovereign entities are also included in this list.

List of countries by oil exports

This is a list of oil-producing countries by oil exports based on The World Factbook [1] and other Sources. Many countries also import oil, and some import more oil than they export.

List of countries by wheat exports

The following is a list of countries by wheat exports. Data are for 2016, in millions of United States dollars, as reported by The Observatory of Economic Complexity. Currently the top twenty countries are listed.

Mutualism (biology)

Mutualism describes the ecological interaction between two or more species where each species benefits. Mutualism is thought to be the most common type of ecological interaction, and it is often dominant in most communities worldwide. Prominent examples include most vascular plants engaged in mutualistic interactions with mycorrhizae, flowering plants being pollinated by animals, vascular plants being dispersed by animals, and corals with zooxanthellae, among many others. Mutualism can be contrasted with interspecific competition, in which each species experiences reduced fitness, and exploitation, or parasitism, in which one species benefits at the "expense" of the other.

Mutualism is often conflated with two other types of ecological phenomena: cooperation and symbiosis. Cooperation refers to increases in fitness through within-species (intraspecific) interactions. Symbiosis involves two species living in close proximity and may be mutualistic, parasitic, or commensal, so symbiotic relationships are not always mutualistic.

Mutualism plays a key part in ecology. For example, mutualistic interactions are vital for terrestrial ecosystem function as more than 48% of land plants rely on mycorrhizal relationships with fungi to provide them with inorganic compounds and trace elements. As another example, the estimate of tropical forest trees with seed dispersal mutualisms with animals ranges from 70–90%. In addition, mutualism is thought to have driven the evolution of much of the biological diversity we see, such as flower forms (important for pollination mutualisms) and co-evolution between groups of species. However, mutualism has historically received less attention than other interactions such as predation and parasitism.The term mutualism was introduced by Pierre-Joseph van Beneden in his 1876 book Animal Parasites and Messmates.


Recycling is the process of converting waste materials into new materials and objects. It is an alternative to "conventional" waste disposal that can save material and help lower greenhouse gas emissions. Recycling can prevent the waste of potentially useful materials and reduce the consumption of fresh raw materials, thereby reducing: energy usage, air pollution (from incineration), and water pollution (from landfilling).

Recycling is a key component of modern waste reduction and is the third component of the "Reduce, Reuse, and Recycle" waste hierarchy. Thus, recycling aims at environmental sustainability by substituting raw material inputs into and redirecting waste outputs out of the economic system.There are some ISO standards related to recycling such as ISO 15270:2008 for plastics waste and ISO 14001:2015 for environmental management control of recycling practice.

Recyclable materials include many kinds of glass, paper, cardboard, metal, plastic, tires, textiles, and electronics. The composting or other reuse of biodegradable waste—such as food or garden waste—is also considered recycling. Materials to be recycled are either brought to a collection center or picked up from the curbside, then sorted, cleaned, and reprocessed into new materials destined for manufacturing.

In the strictest sense, recycling of a material would produce a fresh supply of the same material—for example, used office paper would be converted into new office paper or used polystyrene foam into new polystyrene. However, this is often difficult or too expensive (compared with producing the same product from raw materials or other sources), so "recycling" of many products or materials involves their reuse in producing different materials (for example, paperboard) instead. Another form of recycling is the salvage of certain materials from complex products, either due to their intrinsic value (such as lead from car batteries, or gold from circuit boards), or due to their hazardous nature (e.g., removal and reuse of mercury from thermometers and thermostats).

Rose water

Rose water is a flavoured water made by steeping rose petals in water. Additionally, it is the hydrosol portion of the distillate of rose petals, a by-product of the production of rose oil for use in perfume. It is used to flavour food, as a component in some cosmetic and medical preparations, and for religious purposes throughout Europe and Asia. Rose syrup (not to be confused with rose hip syrup) is a syrup made from rose water, with sugar added.


Slag is the glass-like by-product left over after a desired metal has been separated (i.e., smelted) from its raw ore. Slag is usually a mixture of metal oxides and silicon dioxide. However, slags can contain metal sulfides and elemental metals. While slags are generally used to remove waste in metal smelting, they can also serve other purposes, such as assisting in the temperature control of the smelting, and minimizing any re-oxidation of the final liquid metal product before the molten metal is removed from the furnace and used to make solid metal.

Textile recycling

Textile recycling is the method or process of reusing or reprocessing used clothing, fibrous material, and clothing scraps from the manufacturing process. Textiles in municipal solid waste are found mainly in discarded clothing, although other sources include furniture, carpets, tires, footwear, and non-durable goods such as sheets and towels


Waste (or wastes) are unwanted or unusable materials. Waste is any substance which is discarded after primary use, or is worthless, defective and of no use. A by-product by contrast is a joint product of relatively minor economic value. A waste product may become a by-product, joint product or resource through an invention that raises a waste product's value above zero.

Examples include municipal solid waste (household trash/refuse), hazardous waste, wastewater (such as sewage, which contains bodily wastes (feces and urine) and surface runoff), radioactive waste, and others.

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