3.2 “德拉门德”技术原理 Principle of DARAMEND Technologies

 

德拉门德 (DARAMEND): 这是一个先进成熟的生物“就地/异地”处理技术,专门针对被难分解的有机化合物污染的土壤,底泥,和固体废物。自从1992年,已成功地应用于美国,加拿大,澳大利亚,和欧州,处理700多万吨被污染的土壤和底泥。这些污染物有多环芳烃,五氯酚,邻苯二甲酸盐,氯化除草和杀虫剂,有机易爆化合物和木材防腐剂等。

• 一旦应用于土壤,德拉门德的有机颗粒开始水解,并控制性释放有机物质和营养。 这些有机物质和营养能在有氧和无氧条件下,提供给本地适于以污染物为食的微生物消耗所需的碳源和生长所需的主要,次要,和微量的营养,从而刺激这些微生物在短期内的迅速生长 (请看右图)。微生物新陈代谢所产生的酶能有效地降解污染物。

• 产品颗粒表面电荷能吸附污染物,这样给土壤环境创造了无数的微生物聚集的场所,使污染物在这首先被降解。

• 提供给这些污染降解微生物种群以合适的生长条件也是产品机理的关键。如交替提供有氧和无氧环境证明是更有效的整治策略;温度保持和人工土壤湿度调节等。

• 此外微生物迅速生长的氧消耗和零价铁微小颗粒ZVI的协同作用,使氧化还原潜力降至-500 mV,从而加剧还原环境的形成,使污染物在极度还原的条件下得到还原和稳固。同时暂时地捆束限制急性的有毒物质从而为微生物的生长提供一个安全的环境;

• 它的应用形式是以固体形式投放并与被处理的土壤混合。

DARAMEND? is an advanced biological In-situ/Ex-situ treatment technology for soil, sediment, and solid wastes contaminated with recalcitrant organic compounds. DARAMEND? technology has been used since 1992 to treat over 7,000,000 tons of similarly effected soil and sediment with polycyclic aromatic hydrocarbons (PAHs), PCP, phthalates, chlorinated herbicides and pesticides, organic explosive compounds and wood preservatives at a variety of industrial and military sites in the United States, Canada, Australia and Europe. The use of DARAMEND? can result in substantial cost savings and shorter remediation schedules compared to traditional bioremediation processes, such as composting.

• Once incorporated into the soil matrix, DARAMENDTM organic amendment particles are hydrated and controlled release carbon and nutrients that can provide carbon sources for microbiological consumption and major, minor and micro nutrients for rapid microbial growth to stimulate the growth of indigenous contaminant-degrading microorganisms in anaerobic/aerobic condition. The enzymatic mechanism produced by bacteria results in complete conversion of the contaminant

• The particles also have surface charges that electrostatically draw organic contaminants toward them. In this way the DARAMENDTM Bioremediation Technology creates many microsites where soil contaminants such as PCP are first drawn and then biodegraded.

• The approach with cycled anaerobic and aerobic conditions have been found to be the most effective DARAMEND bioremediation enhances and promotes natural bioremediation rates by adjusting conditions such as moisture, cycled anaerobic and aerobic conditions in a soil matrix to stimulate biodegradation of target compounds.

• Synergistic combination of oxygen consumption by microbes and inorganic amendment (powdered ZVI) allows attainment of redox potentials as low as -500 mV In addition, micro-scale ZVI can create strong reducing conditions in the case of reductive treatment. Meanwhile, transiently bind the contaminants to reduce acute toxicity of the soil’s aqueous phase, allowing the microorganisms to survive

• The application is solid-phase organic soil amendments of specific PSD and nutrient content.

 

德拉门德-M(DARAMEND-M): 是专门设计用来治理土壤中的重金属污染。象EHC-M 产品一样,它能控制释放的碳源和零价铁粉微粒(ZVI),给实地创造一个极低的氧化还原电位,使重金属还原成较稳定的形式而被沉积和吸附,从而限制它们的运动。

DARAMEND-M? is a specially formulated version of Adventus’ controlled-release, integrated carbon and zero valent iron (ZVI) technology for in situ chemical reduction. Similar to EHC-M?, new DARAMEND-M encourages the precipitation and adsorption of arsenic and other dissolved metals (such as chromium, lead and mercury) to limit their mobility.

 

塔拉门德 (TERRAMEND) 是德拉门德的一个低成本版本 (只有德拉门德成本的30%-40%)。但它较为适合可降解的有机物如石油烃类有机物。它能给土壤生物降解环境提供一个较好的主要,次要,和微量营养的平衡。此技术的先进性还表现在于不用异地处理,比起传统的生物整治过程周期短。

TERRAMEND? technology is a lower cost version of DARAMEND for application to more readily degradable organics such as petroleum hydrocarbons,for which TERRAMEND? inorganic soil amendments provide an optimized balance of major, minor, and micronutrients designed to cost-effectively enhance bioremediation of soils without excavation and shorter remediation schedules compared to traditional bioremediation processes.