20171020 Atmospheric and Vacuum Distillation Questions and Answers

Combustion – commonly known as catching fire – refers to an exothermic reaction that occurs when a combustible material reacts with an oxidizer, usually accompanied by flames, light emission, and smoke. Ignition point – refers to the lowest temperature required for a combustible substance to be heated and ignited; this is the substance’s “ignition point”. Also known as the “ignition point”. The lower the ignition point of a substance, the easier it is to burn. Combustion requires the following three essential conditions: a combustible material, an oxidizer (a substance that promotes combustion), and temperature (a source of ignition). Only when all three of these conditions are present can a combustible material burn; without any one of these conditions, combustion cannot occur.

Combustion is an exothermic and luminous chemical reaction whose process is extremely complex; the chain reaction of free radicals is the essence of combustion reactions, while light and heat are physical phenomena that occur during combustion. The ignition point is the lowest temperature at which a substance begins to burn and continues to burn when heated in air. The basic conditions for combustion are: a combustible material, an oxidizer (a substance that facilitates combustion), and temperature (a source of ignition). Combustion can occur only when all three of these conditions are present; without any one of them, combustion is not possible.

Combustion is an exothermic, luminous chemical reaction. The ignition point of a substance is the lowest temperature at which it begins to burn and continues to burn when heated in air. There are three conditions for a substance to burn: (a) the substance itself must be flammable ； (b) The temperature must reach the ignition point of the combustible material ； (c) The combustible material is in full contact with oxygen (or air).

Combustion is a process in which substances combine with each other, accompanied by light and heat production. What we usually refer to as combustion is a violent chemical reaction between a combustible substance and oxygen in the air. For combustibles to burn, a certain temperature is required; the lowest temperature at which a combustible begins to burn is known as its ignition point or burning point. For a substance to burn, the following three basic conditions must be met: (1) A combustible material: Whether solid, liquid, or gas, any substance that can react violently with oxygen in the air or other oxidizing agents is generally considered a combustible material, such as wood, paper, gasoline, alcohol, gas, etc. (2) Oxidizers: Any substance that can assist and support combustion is called an oxidizer. It generally refers to oxygen and oxidizing agents, mainly oxygen in the air. This type of oxygen is called atmospheric oxygen, and it makes up about 21% of the air. Combustible materials will not burn without oxygen participating in the reaction. For example, burning 1 kilogram of oil requires 10-12 cubic meters of air. Burning 1 kilogram of wood requires 4-5 cubic meters of air. When the air supply is insufficient, the combustion gradually weakens until it goes out. Combustion does not occur when the oxygen content in the air is below 14-18%. (3) Heat source: Any energy source that can cause combustible materials to burn is called a heat source, such as an open flame, friction, impact, electric sparks, etc. A substance can burn only when it meets these three conditions. For example, to light a stove, three conditions are necessary: wood (a combustible material), air (an oxidizing agent), and a match (a source of fire).

Combustion is a process in which substances combine with each other, accompanied by light and heat production. What we usually refer to as combustion is a violent chemical reaction between a combustible substance and oxygen in the air. For combustibles to burn, a certain temperature is required; the lowest temperature at which a combustible starts to burn is known as its ignition point or burning point. The basic conditions for material combustion are: first, there must be a combustible substance, such as fuel oil or gas; second, there must be an oxidizing agent, such as air or oxygen; third, there must be an open flame or a high enough temperature. All three are essential.

Combustion is an exothermic, luminous chemical reaction. The ignition point of a substance is the lowest temperature at which it begins to burn and continues to burn when heated in air. There are three conditions for a substance to burn: (a) the substance itself must be flammable ； (b) The temperature must reach the ignition point of the combustible material ； (c) The combustible material is in full contact with oxygen (or air)

Combustion is the process in which a substance oxidizes rapidly, producing light and heat. The ignition point of a substance is the lowest temperature at which it begins to burn and continues to burn when heated in air. For a combustion process to occur and develop, the following three necessary conditions must be present: a combustible material, an oxidizer (a substance that aids combustion), and temperature (a source of ignition). Only when all three of these conditions are met can a combustible material burn; without any one of these conditions, combustion cannot take place.

Combustion is the process in which a substance oxidizes rapidly, producing light and heat. The essence of combustion is a redox reaction. Ignition point: Combustible substances, whether in solid, liquid, or gas state, will burn when in contact with an ignition source once they reach a certain temperature when present in air; they will continue to burn even after the ignition source is removed. At this point, the lowest temperature at which a combustible material can burn is called the ignition point, or flash point. Three conditions must be present for a fire to occur: fuel, an oxidizer, and a heat source. It is generally referred to as the three elements of combustion

1. Combustion is a exothermic, luminous chemical reaction. /2. The lowest temperature required for a combustible material to begin burning continuously. /3. For the occurrence and development of a combustion process, the following three necessary conditions must be present: a combustible material, an oxidizer (a substance that facilitates combustion), and temperature (a source of ignition). Only when all three of these conditions are met can a combustible material burn; without any one of these conditions, combustion cannot take place.

Combustion is a violent chemical reaction that produces light and heat. The ignition point of a substance refers to the lowest temperature at which it begins to burn when heated in air. Three conditions are necessary for combustion to occur: a combustible material, an oxidizer, and a source of ignition. They are generally referred to as the three elements of combustion. (1) Possess a certain amount of combustible material ； (2) There is a sufficient amount of oxidizer. (3) There are a certain number of ignition sources available. All three conditions must be present simultaneously and interact with each other for combustion to occur.