请将以下文档总结为 liquefied natural gas (LNG) 的三个最重要特点，以供非专业读者了解。文档内容如下：  
Liquefied natural gas (LNG) is a clear, colorless, non-toxic liquid that is formed by super-cooling natural gas to -162°C (-260°F). This process reduces the volume of natural gas by more than 600 times, making LNG a practical solution for transporting large volumes of natural gas over long distances, especially when pipeline infrastructure is not available or is not cost-effective. LNG is primarily used for heating, cooking, and electricity generation, and is gaining increasing popularity as an alternate fuel for heavy-duty transportation and shipping. Due to its high energy density, low weight, and ease of transport, LNG is becoming a more viable and competitive alternative to other fossil fuels. Another significant benefit of LNG is its lower environmental impact compared to other fossil fuels; it produces fewer greenhouse gases and other pollutants when burned, making it a cleaner choice for the environment. However, the process of producing LNG, known as liquefaction, is energy-intensive and can result in significant carbon emissions if the energy used is not renewable. Finally, the safety record of LNG operations is very good, thanks to the stringent regulations and best practices in place, but there are still ongoing concerns regarding the safe handling and transportation of LNG to ensure it meets the highest safety and environmental standards.
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LNG（液化天然气）的三个最重要特点包括：首先，通过将天然气冷却至-162°C，LNG的体积可以减少超过600倍，这使得长距离运输大量天然气成为可能，尤其是在没有管道或管道不经济的情境下。其次，LNG具有高能密度、低重量和易于运输的优点，这使得其成为重型运输和航运中越来越受欢迎的替代燃料。最后，LNG相比其他化石燃料对环境的影响较小，燃烧时产生的温室气体和其他污染物较少，更加环保。
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