南通市农村生活垃圾现状调查与处理模式研究

以南通6县(市)农村为研究对象,采用问卷调查、发放调查表等方式对农村生活垃圾现状进行调查,结合垃圾的产生特征分析垃圾的去向及处理方式,提出南通市农村生活垃圾的处理模式。结果表明,南通市农民具有较强的环保意识,能够自觉支持和参与农村的生活垃圾处理。南通市农村生活垃圾平均产生量为0.69kg/(人.d),乡镇垃圾产生量[y,kg/(人.d)]与经济发展水平(x,乡镇年生产总值,单位:百万元)呈y=0.191 4 lnx-0.462 4的关系。生活垃圾组成以可堆肥有机物和能就地填埋的无害无机物为主;根据不同组分,垃圾去向可为回收、堆肥、焚烧、填埋等方式的组合,应采用分类收集、分类处理的组合模式进行处理。     

餐厨垃圾生化尾渣蚯蚓堆肥中矿物的调节效应

餐厨垃圾生化尾渣的资源化利用是餐厨垃圾生化处理后的新难点,针对餐厨垃圾生化尾渣中的高盐分和低腐熟度问题,本研究以脱硫石膏和骨炭作为添加剂,探究脱硫石膏与骨炭对餐厨垃圾生化尾渣蚯蚓堆肥中的调节效应,研究其对蚓体生长及蚯蚓堆肥基本性状变化规律的影响。结果表明:脱硫石膏和骨炭添加均可促进蚯蚓生长繁殖,且骨炭添加下蚯蚓生长状况相对更优;蚯蚓处理可降低蚯蚓堆肥pH而提高其电导率(EC)和总养分含量;骨炭较之脱硫石膏添加下所获蚯蚓堆肥pH、总养分含量和过氧化氢酶(CAT)活性均升高,而其EC、脲酶(UA)和碱性磷酸酶(AKP)活性则均降低。腐熟度变化表明,蚯蚓活动和骨炭添加均可降低堆肥中C/N和NH⁺₄-N/NO^-₃-N,增加其腐殖质(HS)、胡敏酸(HA)、富里酸(FA)含量和种子发芽指数(GI)。因此,在餐厨垃圾生化尾渣中添加骨炭进行蚯蚓堆肥以降低盐分和提高腐熟度具有一定可行性。     

Colloid formation during waste form reaction: implications for nuclear waste disposal

Insoluble plutonium- and americium-bearing colloidal particles formed during simulated weathering of a high-level nuclear waste glass. Nearly 100 percent of the total plutonium and americium in test ground water was concentrated in these submicrometer particles. These results indicate that models of actinide mobility and repository integrity, which assume complete solubility of actinides in ground water, underestimate the potential for radionuclide release into the environment. A colloid-trapping mechanism may be necessary for a waste repository to meet long-term performance specifications.     

Thermodiffusional transport in pelagic clay: implications for nuclear waste disposal in geological media

Thermal gradient experiments in sediment-seawater systems revealed large-scale fluxes of aqueous electrolytic components away from the heat source through thermal diffusion. These findings indicate a need for similar studies in other geological materials of low permeability in order to assess the implications of this phenomenon for various nuclear waste disposal options.     

Disposal of radioactive wastes

Scientists appointed by the International Council of Scientific Unions have concluded that nuclear wastes may be safely disposed of using current technology. Interim storage for 50 to 100 years greatly reduces the problem of thermal loading at the final disposal sites, but more research devoted to such interim storage is needed.