CNN News:美国食物垃圾占供应量40% 新技术将垃圾变为电力

AZUZ: According to the United Nations, food waste is defined as food that's initial safe for people to eat, but it doesn't get eaten because it's left to spoil or it's thrown out. The U.S. government estimates that food waste in America could be as high as 40 percent of the food supply.
But there is a process that ensures that food left to waste doesn't stay that way.
REPORTER: Americans send more than 30 million tons of food to the landfill every year. But as the saying goes, "One person's trash is another's treasure" — really smell treasure.
BOB YOST, A1 ORGANICS, VICE PRESIDENT: We're not dealing with the Bed, Bath and Beyond. These are the smells of nature.
REPORTER: Welcome to Heartland Biogas, a facility in rural Colorado that takes food waste from all over the state and turns it into electricity.
YOST: The waste comes from grocery stores, from cafeterias, from restaurants, packing houses, meat preparation, dog food or pet food manufacturing facilities, food processors, just about any place that has a food-based waste.
阿祖兹：联合国对食物垃圾的定义是，本来是可以安全食用的食物，但因为剩下后变质或被扔掉而不再适宜食用。美国政府估计，美国的食物垃圾可能占食物供应的40%。
但是有一个处理方法可以使食物垃圾有其他的用处。
记者：美国人每年将3000余万吨食物丢进垃圾堆。但是俗话说，“一个人的垃圾是另一个人的宝藏”——有味道的宝藏。
A1 ORGANICS副主席鲍勃·约斯特：我们没有同床上及家庭用品公司打交道。这些是大自然的味道。
记者：欢迎来到Heartland Biogas，这里位于科罗拉多州郊区，负责将全州的食物垃圾转变成电力。
约斯特：这些垃圾来自食杂店、自助餐厅、餐厅、包装工厂、肉类准备工厂、狗粮或宠物食品制造工厂、食物处理器等任何可以产生食物垃圾的地方。

REPORTER: The process Heartland uses is called anaerobic digestion, and as the name implies, it works just like our human digestive systems, by breaking down food into energy, in this case, electricity.
The food waste that comes into the facility is separated from any packaging, chewed up into a more digestible state, and mixed with bacteria, in one of Heartland's 1.7 million gallon holding tanks. And while in human digestion, gas is far from being the goal. Gas is exactly what Heartland is after.
Remember the smell from before? It's methane and it's a great source of renewable energy.
YOST: We create three things: gas, liquid soil amendment, and solid soil amendment of peat moss like material.
The digester is just like your stomach's bacteria. The bacteria eat the organics and then they create gas. Not unlike what we do.
REPORTER: Methane is a powerful greenhouse gas. So, when food rots in a landfill and sends gas into the atmosphere, it's bad news for the environment. In fact, if global food waste were a country, it would be the world's third largest emitter of greenhouse gases. The methane made in Heartland's digesters is pumped into an interstate pipeline where it can be accessed as a source of clean renewable power, all while cutting on harmful emissions.
YOST: The vast majority of the materials that we processed were originally landfill or disposed of. We can process up to 1,200 tons a day. That's really good size landfill. If you're doing 240,000 tons a year into a landfill, that's a lot of waste. This is a very efficient and impactful way to be capturing that resource.
记者：Heartland使用的处理方法叫做厌氧消化，顾名思义，其工作原理同我们人类的消化系统类似，就是将食物分解成能量，在这里就是转化成电力。
通过这个设施处理的食物垃圾从包装中隔离出来，转化成更易消化的状态，然后在Heartland公司170万加仑的收集罐中同细菌混合在一起。对人类消化系统来说，最终的目标肯定不是气体。而气体却是Heartland公司想要的结果。
还记得我们刚刚提到的气味吗？那是甲烷，是可再生能源的重要来源。
约斯特：我们的目标有三个：气体，类似泥炭沼泽的液体土壤改良和固体土壤改良。
浸煮器就像你胃里的细菌。细菌吃掉有机物，然后生成气体。和我们做的很像。
记者：甲烷是一种强大的温室气体。所以，当食物在垃圾堆里腐烂时，会将气体扩散到大气中，这对我们的环境很不利。实际上，如果把全球食物垃圾比作一个国家，那它可能会成为世界第三大温室气体排放国。在Heartland的浸煮器里产生的甲烷被注入一个州际管道里，用作清洁可再生能源的来源，同时可以减少有害排放。
约斯特：我们处理的绝大部分物质来自垃圾堆或被处理的东西。我们每天可以处理1200吨。那是很多垃圾。如果一年扔24万吨垃圾，那非常浪费。而这种方法则是高效又有效的资源获取方法。