Ze-Gen, based in Massachusetts, gasifies waste by injecting it into molten steel.The syngas rises through the pool, heavy metals sink to the bottom and other contaminants form a slag on top.

• 资杰，一家位于麻省的垃圾处理公司，通过把废弃物注入高温融化的钢水池气化，可燃混合气上升溢出，重金属在底下沉淀，其他的污染物则形成熔渣浮在表层。