The most common volatile matter in coal is water, carbon dioxide, and sulfur dioxide. Volatile matter is directly related to coal rank; as rank increases, volatile matter content decreases (Stach and others, 1982).
What is volatile material?
Volatility describes how easily a substance will vaporize (turn into a gas or vapor). A volatile substance can be defined as (1) a substance that evaporates readily at normal temperatures and/or (2) one that has a measurable vapor pressure. The term volatile usually applies to liquids.
Which is preferred for high volatile coal and why?
Generally, the highest value bituminous coals have a specific grade of plasticity, volatility and low ash content, especially with low carbonate, phosphorus, and sulfur. … Coking coal is best if it has a very narrow range of volatility and plasticity. This is measured by the free swelling index test.
Which of the coal have the best heating values in terms of volatile matter?
3. Which of the coal have the best heating values in terms of volatile matter? Explanation: Coals containing high volatile matter produces long and smoky flame due to which its heating value decreases. Semi-bituminous coal has the highest heating value due to less volatiles content.
What is the temperature for determination of volatile matter?
Volatile matter is determined as the loss in mass, less that due to moisture, when a sample is heated at 900 degrees Celsius for a period of 7 minutes. This procedure is undertaken out of contact with air under standardised conditions.
Which one is more volatile?
– Volatility of compounds depends on polarity and molar masses. – More polar the molecule, less volatile it is. – Lower molar mass results in more volatility. – Therefore, CHCl3 is most volatile of them all.6 мая 2018 г.
Which liquid is the most volatile?
Bromine liquid readily transitions to vapor at room temperature, indicating a high volatility.
What are the 4 types of coal?
Coal is classified into four main types, or ranks: anthracite, bituminous, subbituminous, and lignite.
Is high volatile matter in coal Good?
High-volatile matter may also be associated with spontaneous combustion, especially in low-rank coals (Fierro and others, 1999). Hence, knowledge of volatile matter is important for safety, handling, and transporting coal.
Which country has the best quality coal?
Experts told Fact Check that Australia’s coal is on average high quality as a result of its low moisture and ash content, and high carbon content, compared with other countries, particularly Indonesia, the largest coal exporter in the world.
What is the effect of volatile matter in coal?
The volatile content has a positive effect on the volatilization rate of arsenic in the initial stage of combustion. With the same level of ash content, high-volatile coals (>30%) own a larger volatilization rate of arsenic (0.55–0.6% s–1) than the low-volatile coals (<12%) (0.25% s–1).
Which coal has highest ash content?
Which coal has the highest sulfur content?
What is meant by ash content?
Ash content represents the incombustible component remaining after a sample of the furnace oil is completely burned. The ash content of petroleum products is generally low. It is defined as inorganic residue that remains after combustion of the oil in air at specific high temperature. Ash ranges from 0.1–0.2%.
What is non volatile material?
In chemistry, the term nonvolatile refers to a substance that does not readily evaporate into gas under existing conditions. In other words, a nonvolatile material exerts a low vapor pressure and has a slow rate of evaporation.
At what temperature moisture and ash present in coal are removed?
Coal sample is heated at 105-110 ℃ temperature for removal of moisture and ash. – Coal is the most common form of energy used on industrial scale. – To remove ash and moisture, coal sample is first heated at 105-110 ℃ in silica crucible.