Novel Low-Temperature Plasma-Catalyst Control of Dioxin & Furan Emissions from Waste Incinerators

每年有超过1000万吨的英国垃圾被焚烧成废物工厂的能源，为英国的能源需求做出了相当大的贡献。环境局透过《环境许可规例》规管废物焚化炉的排放，该规例为多种污染物，包括微粒、挥发性有机化合物、一氧化碳、氯化氢、氟化氢、二氧化硫、氮氧化物、重金属和二恶英/呋喃，订出严格的排放限值。垃圾焚烧炉的排放控制系统占资本和运营成本的很大比例。废物焚烧炉向大气排放二恶英和呋喃的问题引起了相当大的公众、政治和科学关注。围绕二恶英/呋喃的问题与它们的高毒性、严重的健康危害和对环境中降解的抵抗力有关。二恶英/呋喃对人体免疫、神经和生殖系统造成损害，也是疑似致癌物质。因此，令人关切的是，即使长期接触极少量的二恶英/呋喃，也会对人类健康和环境造成负面影响。根据欧共体工业排放指令即将出台的立法，将通过环境许可法规纳入英国法律，为垃圾焚烧炉设定了强制性的、严格的新的每日排放限制值。对于大多数焚烧炉设施，二恶英/呋喃的排放限值将从0.1 ng m-3降至0.01 ng m-3。目前控制二恶英/呋喃排放的最常见方法是使用添加的活性碳试剂从烟道气中吸附二恶英/呋喃，然后使用织物滤袋进行捕获。使用活性碳是一种高成本的方法，只是将二恶英/呋喃转移到废气控制残留物中，然后处置到高成本的危险废物填埋场。本研究的目的是开发一种新的、低成本、低温(~150℃)的等离子体-催化剂工艺，在模拟典型垃圾焚烧烟气的烟道条件下分解二恶英/呋喃。使用模型氯化芳香族模型化合物进行的补充研究将有助于从机理上解释二恶英/呋喃在非热等离子体催化条件下的分解，从而有助于开发二恶英/呋喃控制系统。

More than 10 million tonnes of UK waste is incinerated in energy from waste plants each year, making a considerable contribution to UK energy demand. The emissions from waste incinerators are regulated by the Environment Agency through the Environmental Permitting Regulations which sets stringent emission limit values for a wide range of pollutants, including, particulate, VOCs, CO, HCl, HF, SO2, NOx, heavy metals and dioxins/furans. The emissions control system for waste incinerators represents a major proportion of the capital and operational costs. The emissions of dioxins and furans from waste incinerators into the atmosphere are of considerable public, political and scientific concern. The issue around dioxins/furans is associated with their high toxicity, significant health hazard and resistance to degradation in the environment. Dioxins/furans cause damage to the human immune, nervous and reproductive systems and are also suspected carcinogens. There is consequently concern over the negative effects on human health and the environment of long-term exposure to even very small amounts of dioxins/furans. Impending legislation under the EC Industrial Emissions Directive that will be transposed into UK Law via the Environmental Permitting Regulations has set mandatory stringent new Daily Emission Limit values for waste incinerators. Dioxin/furan emission limits are to reduced from 0.1 ng m-3 to 0.01 ng m-3 for most incinerator installations. The current most common method for control of dioxin/furan emissions uses added activated carbon reagent for the adsorption of the dioxins/furans from the flue gas followed by capture using fabric filter bags. The use of activated carbon is a high cost method and merely transfers the dioxins/furans to the flue gas control residue and subsequent disposal to high cost hazardous waste landfill. The aim of this research proposal is to develop a novel, low cost, low temperature (~150 C), non-thermal plasma-catalyst process to decompose dioxins/furans under flue duct conditions simulating those of typical waste incineration flue gases. A complementary study using model chlorinated aromatic model compounds will aid a mechanistic interpretation of the decomposition of dioxins/furans under non-thermal plasma-catalysis conditions, aiding the development of the dioxin/furan control system.