Utilization of gutter oil

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Gutter oil refers to various types of low-quality oils found in daily life, such as recycled cooking oil and oil that has been reused for frying; consuming it over time can lead to cancer and poses serious risks to human health. Due to significant financial incentives, some people still take the risk of selling gutter oil. In response to public concerns regarding the issue of gutter oil, the General Office of the State Council issued a document in July 2010, deciding to launch pilot projects on the resource utilization and harmless treatment of gutter oil and other urban food waste. On September 13, 2011, the Chinese police solved a major case involving the production and sale of products made from \"gutter oil\" in its entirety. 　When it comes to \"gutter oil,\" people’s first reaction is that it is a type of edible oil of extremely poor quality and unhygienic. As people might think, consuming \"gutter oil\" can damage one’s white blood cells and the mucous membranes of the digestive tract, leading to food poisoning and even serious consequences such as cancer. Therefore, \"gutter oil\" is strictly prohibited from being used in the edible oil industry. However, there are indeed some unscrupulous vendors who, driven by profit, ignore the safety of people’s lives by illegally producing and processing \"gutter oil,\" which is then sold at low prices to small restaurants as cooking oil, causing great harm to people’s physical and mental health. Therefore, the term “gutter oil” has become a synonym for all kinds of low-quality oils that cause physical harm in people’s lives. 　　 Academic Research Achievements “Many people prefer foods without food additives; in fact, without such additives, there would be no modern foods.” Sun Baoguo explained that food safety is impossible without food additives. Taking edible oil as an example, in the past the oil would go bad already by the following year, yet it still had to be consumed ； And now, thanks to the addition of antioxidant ingredients, the shelf life of edible oils can be extended. Additionally, both soy sauce and vinegar contain preservatives, so they won’t spoil even after being stored for a long time. “If preservatives are not added, consuming spoiled food can be even more harmful! ” Some experts say that to date, the food safety incidents that have had negative effects in China have not been caused by food additives. Sun Baoguo believes that in many food safety incidents, food additives serve as the \"scapegoats\". 　　 　　Sun Baoguo believes that issues related to human factors, such as inadequate supervision and weak corporate self-discipline, are responsible for the frequent occurrence of food safety incidents. In fact, ‘ractopamine’ is also used in pig farming in the United States, but it has not caused any major incidents. Because they use intensive farming methods; if they know that the pigs will be sold in a few weeks, they don’t feed them ‘lean meat powder’. By the time of sale, the ‘lean meat powder’ had already been excreted. ” 　　 　　Furthermore, there are also some food safety topics that contain fabricated elements. Sun Baoguo gave an example, stating that \"gutter oil\" has turned out to be a \"gutter oil scam\". “In fact, there is no such thing as ’gutter oil’ anywhere; people refer to it as oil derived from swill, but nowadays there is very little swill left, and if any does exist, it is collected and used to produce biofuel or soap. ”Scientifically speaking, “‘gutter oil’ has a very strong odor; to eliminate this odor would require substantial costs. Therefore, it’s impossible for it to end up back on dining tables.” ” Specific classifications: Gutter oil (in fact, it is a general term used by people in everyday life to refer to various types of low-quality oils). 　　 　　Gutter oil can be divided into three categories: The first is the narrow sense of gutter oil, which refers to the oil obtained through simple processing and extraction of greasy substances floating in sewers, or of leftover food from hotels and restaurants (commonly known as swill). 　　 　　Second is oil produced from the processing and refining of low-quality pork, pig offal, and pig skin. 　　 　　Third is the oil used for fried foods, which, after being used a certain number of times, is reused either as is or after some new oil is added to it. 　　 　　During inspections, law enforcement officers use rapid test strips for detecting rancidity in edible oils, to check whether the peroxide value and acid value of the oil in question exceed the permissible limits; if they do, it can be determined that the oil is defective. Proper use: Gutter oil can be used to produce biodiesel. It is a troubling issue that gutter oil ends up on our dining tables again; the best solution is to recycle it and turn waste into treasure. How can we turn waste into treasure? Fujian Zhuoyue New Energy Development Co., Ltd. has found a new way to do this. By utilizing self-developed technologies and equipment, they have successfully refined biodiesel from waste animal and vegetable oils, becoming the first company in China to achieve its industrialization. 　 　　According to experts, once gutter oil is added to the reaction tank, a slightly acidic catalyst is used to enable both alcoholysis and esterification to occur simultaneously, thereby significantly increasing the reaction rate. Furthermore, a metal salt treatment agent was used to solve the key problem of high residual acid value in diesel produced from waste animal and plant oils. These two key technologies can reduce the production cost of biodiesel, enabling it to move from the laboratory to production facilities. The greatest advantage of this fuel is its excellent environmental compatibility; diesel vehicles using it do not emit sulfur dioxide in their exhaust gases, and levels of hydrocarbons and carbon monoxide are also **reduced**. In their research on using gutter oil to produce biodiesel, technicians found that determining how to extract waste oils from the debris in oil separation tanks was a major obstacle to advancing this project. Through research on the characteristics of gutter oil, technicians, guided by fuzzy mathematics and biochemistry, developed a green oil-separating tank waste treatment device that generates zero energy consumption and causes no pollution. 　　 Using \"gutter oil\" to produce flotation reagents Professor Wang Huajun from the Department of Environmental Engineering at University of Science and Technology Beijing and his colleagues have developed a comprehensive technology for utilizing \"gutter oil\" to create flotation reagents. This technology enables the production of fatty acids and sodium fatty acids for use in flotation processes, with almost no risk of secondary pollution. 　　 　　In 2009, the University of Science and Technology Beijing began research on using fatty acids derived from recycled cooking oil as flotation collectors, and achieved satisfactory experimental results. Currently, this technology has begun to be applied in some steel companies, and a **patent application is underway. 　　 　　It is reported that fatty acids are commonly used flotation collectors in the processing of iron ore, fluorite ore, apatite ore, etc., with a typical dosage of 0.5 kilograms per ton of ore. According to rough estimates, the country’s ore flotation process requires 500,000 to 800,000 tons of fatty acid-based collectors per year. Traditionally, fatty acids are produced through chemical synthesis, but in recent years, as costs have risen, there has been increasing interest in using waste materials for their production. Currently, in research on producing mineral fatty acid collectors from waste materials, the main raw materials used are refined vegetable oils, as well as oil residues or intermediate products discarded during the production of acidified oils; the use of \"gutter oil\" to manufacture fatty acid collectors is still relatively rare. Since \"gutter oil\" mainly comes from waste fats and oils from the food service industry, with fatty acid glycerides as its primary components, utilizing it for the production of fatty acid-based collectors can achieve both pollution reduction and comprehensive utilization. 　　 　　Experts believe that further research and broader application of this technology will be of great significance in preventing environmental pollution, reducing mining costs, and minimizing threats to food safety. 　　 “New technologies for producing ethanol and biogas from “gutter oil”
After being sorted and separated, batches of food waste are processed: part of it becomes raw material for biodiesel, while the rest undergoes fermentation to produce fuel ethanol and biogas. The remaining waste residue is entirely converted into fertilizer. This is the process of resource utilization for kitchen waste as witnessed on Hefei Science Island. Thanks to technological integration and innovation, what used to be troublesome issues—kitchen waste and “gutter oil”—have now been transformed from waste into valuable new energy sources. 　　 　　Through years of technical research, scientists from the Institute of Plasma Physics, Chinese Academy of Sciences, have successfully developed technologies for the energy-based treatment of kitchen waste to produce ethanol and biogas, resulting in two invention patents. It is said that this technology transforms kitchen waste into four valuable products: biodiesel, ethanol, biogas, and biofertilizer. The fats in food waste are first separated and refined to produce biodiesel, while components such as carbohydrates and proteins are converted into fuel ethanol through processes like enzymatic hydrolysis and anaerobic fermentation. The residues from ethanol fermentation along with other organic components are used to generate biogas through fermentation, and the sludge and liquid resulting from biogas production are processed into biological fertilizers. 　　 　　It is understood that the greatest feature of this technology is that its approach to energy utilization differs from the domestically prevalent technology route, which primarily focuses on feed production. This helps prevent food waste from re-entering the human food chain, thereby reducing the risk of diseases caused by homologous accumulation. 　　 “\"Gutter oil\" turned into aviation fuel 　　　 Starting in September 2011, KLM will make a new breakthrough by processing oil used for cooking in order to use it as fuel for aircraft. “\"Gutter oil\" turned into aircraft fuel: costs have risen sharply, but it is more efficient and greener. 　　 　　How do vegetable oils get converted into aviation fuel? SkyNRG uses “hydrogenated renewable aviation fuel” technology. 　　 　　First, the vegetable oil is deoxygenated. Then, a series of organic chemical processes follow; the key step is hydrocracking. Under continuous hydrogen pressure, the carbon bonds between molecules are broken, resulting in the formation of smaller hydrocarbons. The product at this stage is unsaturated hydrocarbons, which are already quite close to being fuel. Finally, “isomerization” takes place—that is, the chemical structure of the substance is altered, thereby producing the desired “renewable aviation fuel.” 　　 　　But in Deke’s view, in the process of turning “gutter oil” into a useful resource, the biggest obstacle is not the technical barrier, but the legally mandated high standards. The EU has high requirements for biofuels; not just any material can be used as fuel for commercial purposes. 　　 　　According to KLM President Camiel Eurlings, as early as 2009, a KLM Boeing 747 used 50% biofuel in its engines, proving that flying using bio-kerosene is technically feasible. But it was not until this year that the “hydrogenated renewable aviation fuel” technology received certification from the International Organization for Standardization, allowing its use in commercial flights. Crossing the “legal threshold” directly led to KLM’s decision. On June 22, KLM announced that starting in September it would use \"used cooking oil\" fuel on 200 flights between Amsterdam and Paris, thereby creating a \"green flight corridor\". According to KLM’s statement, the airline does not need to make any changes to the aircraft engines in order to use \"used cooking oil\" as fuel. Testing standards 　　At present, there are no unified standards for testing gutter oil in China. Under the current **mandatory standard, the Hygienic Standards for Edible Vegetable Oils (2716—2005), the physical and chemical parameters of edible oils that are subject to testing include acid value, peroxide value, residual solvents in extracted oils, free phenols (in cottonseed oil), total arsenic, lead, aflatoxins, benzo[a]pyrene, and pesticide residues – a total of 9 parameters. Different testing standards apply to crude vegetable oils and edible vegetable oils respectively. 　　 　　However, both vegetable crude oil and vegetable edible oil are not gutter oil. Among these 9 basic testing indicators for edible oil stipulated in the standards, even oil refined from gutter oil may meet the criteria. Therefore, it is impossible to conduct discriminatory tests specifically for gutter oil. The Ministry of Health stated that, in accordance with the unified arrangements of the State Council’s Food Safety Office, it organized the Ministry of Science and Technology, the State Administration for Industry and Commerce, the General Administration of Quality Supervision, Inspection and Quarantine, the National Medical Products Administration, the State Grain Administration, as well as the Chinese Center for Disease Control and Prevention, among other relevant parties, to jointly develop a plan for evaluating testing methods for \"gutter oil\". An expert group for evaluating these testing methods was formed, comprising authoritative experts in fields such as oil processing, food safety, hygiene inspection, and chemical analysis, as well as relevant institutions, in order to conduct scientific evaluations of the testing methods developed by various technical institutions. Specific harms: Digestive problems. During the process of producing \"gutter oil,\" animal and plant oils become contaminated, undergoing a series of chemical changes such as rancidity, oxidation, and decomposition, which result in the formation of substances that are highly toxic to the human body ； Arsenic is one of such substances; when people consume large amounts of \"gutter oil\" containing arsenic, it can cause symptoms such as indigestion, headaches, dizziness, insomnia, fatigue, and discomfort in the liver area. Diarrhea: The manufacturing process of “gutter oil” inevitably makes it unhygienic. The large number of harmful microorganisms, such as bacteria and fungi, contained in it can, once they enter the human intestines, cause diarrhea in mild cases; in severe cases, they may lead to a range of gastrointestinal disorders, including nausea and vomiting. Abdominal pain: \"Gutter oil\" contains large amounts of sewage, trash, and detergents; when processed in open-air workshops underground, it is impossible to remove bacteria and harmful chemical substances. It is an undisputed fact that all \"used cooking oil\" contains excessively high levels of lead, and consuming foods made from such oil with excessive lead content can cause severe abdominal cramps, anemia, toxic liver disease, and other symptoms. Stomach cancer and colon cancer: The disgusting processing methods are the cause of the toxins produced by gutter oil. “\"Reused cooking oil\" refers to refined oil that is produced by processing waste food and grease collected from hotels and restaurants, removing their unpleasant odor, and then putting it on the market as edible oil. Swill oil contains aflatoxin and benzo[a]pyrene, both of which are carcinogenic toxins that can cause cancers such as stomach cancer, intestinal cancer, kidney cancer, as well as cancers of the breast, ovaries, small intestine, and other organs. 　　 　　Proctologists urge consumers to seek medical attention at a hospital as soon as possible if they experience symptoms such as abdominal pain, nausea, or vomiting after eating at restaurants, street stalls, or other food outlets, in order to prevent further damage to their health. 　　 　　Waste oil is non-edible oil of extremely poor quality and unhygienic, with severely excessive levels of peroxide value, acid value, and moisture. It contains toxins; when it flows into rivers, it causes eutrophication of the water bodies. If consumed, it damages white blood cells and the mucous membranes of the digestive tract, leading to food poisoning and even cancer. “Frying oil, one of the types of vegetable oils, when used repeatedly at high temperatures and in contact with oxygen in the air, undergoes complex reactions such as hydrolysis, oxidation, and polymerization. As a result, the viscosity of the oil increases, its color deepens, and its peroxide value rises. Additionally, volatile substances as well as irritating-smelling compounds such as aldehydes and lactones are produced; these substances have carcinogenic properties. “The main harmful substance in \"swill oil\" – aflatoxin – is 100 times more toxic than arsenic.