This research demonstrated the feasibility of converting source-separated human urine into a solid fertilizer by means of continuous absorption and solar thermal evaporation using dried water hyacinth as adsorbent. In...This research demonstrated the feasibility of converting source-separated human urine into a solid fertilizer by means of continuous absorption and solar thermal evaporation using dried water hyacinth as adsorbent. In a preliminary experiment, the dried petioles of water hyacinth (DWH) absorbed urine in a mean rate of 18.78 ml·g-1 within 7 d, retrieving about 3.46% urine dissolved solids (UDS). In an advanced experiment, the DWH’s capacity of urine absorption declined from an initial 2.73 L·kg-1·d-1 to 0.68 L·kg-1·d-1, with a requirement of material change in about 25 effective days and an average ratio of 25 (L) to 1 (kg). Phosphorus (P2O5) concentration in the adsorbent increased from 0.46% (material baseline) to 3.14% (end product), suggesting a satisfactory recovery of the element. In field application, the urine was discharged, not in wet weather, onto the DWH via a tube connected to a waterless urinal. There are several ways to use the UDS-DWH as P(K)-rich fertilizer, e.g., making soluble fertilizer for foliage spraying to encourage prolific flowering and fruiting. Apparently, utilization of water hyacinth waste to recover dissolved plant nutrient elements from source-separated urine will benefit the environment in a wide range of perspectives. The herein innovative use of water hyacinth is also expected to be useful in the recycling of certain dissolved hazardous materials.展开更多
Freeze concentration has great potential in treating wastewaters containing soluble pollutions. It is important for freeze concentration process to produce ice crystals with large size and high purity. In this work ra...Freeze concentration has great potential in treating wastewaters containing soluble pollutions. It is important for freeze concentration process to produce ice crystals with large size and high purity. In this work raw urines of 4660 -7914 mg/L in COD, 512. 71 -872. 41 mg/L in NH3 -N and 22600 -28800 μs/cm in electric conductivity were studied. Urines were frozen by a digital refrigerated circulator bath. Ice crystals were purified by ice-water steep and vacuum filtration. The COD, NH3 - N, and electric conductivity levels of the melted ices were measured to reflect ice crystal purity. Effects of coolant temperature, ice crystal shape, initial solution temperature, solution concentration, ice seeding, re-crystallization process and crystallization time on ice crystal purity were analyzed. The results show that an appropriate coolant temperature, suspended ice crystals, an initial solution temperature of about 6 ℃, introduction of seed ice, addition of re-crystallization process, and crystallization time of less than 30 min axe in favor of producing ice crystals with high purity. Under such conditions, more than 99 percent of inorganic salts, COD and NH3 - N sources in raw urine could he removed.展开更多
针对受控生态生保系统(CELSS)中生活废水(含卫生废水和尿液废水)的水质特点,采用厌氧、好氧两级MBfR工艺,完成CELSS特征性生活废水的微生物转化处理,以达到循环回用作植物营养液的水质要求。本文研究了水力停留时间(HRT)、尿液强度对该...针对受控生态生保系统(CELSS)中生活废水(含卫生废水和尿液废水)的水质特点,采用厌氧、好氧两级MBfR工艺,完成CELSS特征性生活废水的微生物转化处理,以达到循环回用作植物营养液的水质要求。本文研究了水力停留时间(HRT)、尿液强度对该工艺有机物去除及氮素转换效率的影响。试验结果表明,当HRT≥1 d时,HRT对该系统TOC的去除效率无明显影响,其去除效率大于90%,出水TOC的浓度低于15 mg/L;HRT=1 d时,好氧反应器全程硝化能力达到最高,其容积负荷为0.418 kg N/(m^3·d);而HRT≥2 d时,能获得相对更为稳定的氮素转换效率。工艺系统最高能处理1/5尿液强度的生活废水,该条件下,系统TOC的去除率达94.3%,出水TOC浓度低于20 mg/L;系统氮素的全程硝化效率为90.6%,且反应器容积负荷较高为0.409 kg N/(m^3·d)。本文构建的两级MBfR工艺能较好地实现CELSS中特征性生活废水的有机物去除和氮素的有效转换,研究结果可为CELSS中生活废水微生物处理系统的设计和运行提供参考。展开更多
尿液因其含有丰富的氮、磷、有机物等营养物质,被称为“废水中的黄金”,其如何处理废弃资源并实现高效资源化利用已成为环境工程领域科研人员关注的焦点。基于Web of Science数据库对“尿液废水”、“源分离尿液”等关键词进行检索分析...尿液因其含有丰富的氮、磷、有机物等营养物质,被称为“废水中的黄金”,其如何处理废弃资源并实现高效资源化利用已成为环境工程领域科研人员关注的焦点。基于Web of Science数据库对“尿液废水”、“源分离尿液”等关键词进行检索分析、归纳总结,将目前处理源分离尿液废水的研究分为氮去除(回收)、磷回收、产电及其他等4个方面。进一步对其处理技术分析发现:1)氮回收主要通过吹脱、离子交换吸附、电化学等技术实现;2)磷回收则多以化学沉淀技术为主;3)基于生物电化学技术,尿液中有机化学能可回收电能,为其资源化利用提供新的途径。然而,由于尿液废水成分复杂、氮磷等污染物浓度高,现有单一技术难以实现其中多种物质或能量形式的同时处理与利用,且回收效果及成本仍不能满足实际应用要求,高效稳定的一体化源分离尿液废水处理技术仍需进一步深入研究。通过系统总结处理现状及研究进展,有利于加深对源分离尿液废水资源化处理技术应用的认识,具有一定的指导意义。展开更多
文摘This research demonstrated the feasibility of converting source-separated human urine into a solid fertilizer by means of continuous absorption and solar thermal evaporation using dried water hyacinth as adsorbent. In a preliminary experiment, the dried petioles of water hyacinth (DWH) absorbed urine in a mean rate of 18.78 ml·g-1 within 7 d, retrieving about 3.46% urine dissolved solids (UDS). In an advanced experiment, the DWH’s capacity of urine absorption declined from an initial 2.73 L·kg-1·d-1 to 0.68 L·kg-1·d-1, with a requirement of material change in about 25 effective days and an average ratio of 25 (L) to 1 (kg). Phosphorus (P2O5) concentration in the adsorbent increased from 0.46% (material baseline) to 3.14% (end product), suggesting a satisfactory recovery of the element. In field application, the urine was discharged, not in wet weather, onto the DWH via a tube connected to a waterless urinal. There are several ways to use the UDS-DWH as P(K)-rich fertilizer, e.g., making soluble fertilizer for foliage spraying to encourage prolific flowering and fruiting. Apparently, utilization of water hyacinth waste to recover dissolved plant nutrient elements from source-separated urine will benefit the environment in a wide range of perspectives. The herein innovative use of water hyacinth is also expected to be useful in the recycling of certain dissolved hazardous materials.
基金Sponsored by the High Technology Research and Development Programm of China(Grant No.2002AA743022).
文摘Freeze concentration has great potential in treating wastewaters containing soluble pollutions. It is important for freeze concentration process to produce ice crystals with large size and high purity. In this work raw urines of 4660 -7914 mg/L in COD, 512. 71 -872. 41 mg/L in NH3 -N and 22600 -28800 μs/cm in electric conductivity were studied. Urines were frozen by a digital refrigerated circulator bath. Ice crystals were purified by ice-water steep and vacuum filtration. The COD, NH3 - N, and electric conductivity levels of the melted ices were measured to reflect ice crystal purity. Effects of coolant temperature, ice crystal shape, initial solution temperature, solution concentration, ice seeding, re-crystallization process and crystallization time on ice crystal purity were analyzed. The results show that an appropriate coolant temperature, suspended ice crystals, an initial solution temperature of about 6 ℃, introduction of seed ice, addition of re-crystallization process, and crystallization time of less than 30 min axe in favor of producing ice crystals with high purity. Under such conditions, more than 99 percent of inorganic salts, COD and NH3 - N sources in raw urine could he removed.
文摘针对受控生态生保系统(CELSS)中生活废水(含卫生废水和尿液废水)的水质特点,采用厌氧、好氧两级MBfR工艺,完成CELSS特征性生活废水的微生物转化处理,以达到循环回用作植物营养液的水质要求。本文研究了水力停留时间(HRT)、尿液强度对该工艺有机物去除及氮素转换效率的影响。试验结果表明,当HRT≥1 d时,HRT对该系统TOC的去除效率无明显影响,其去除效率大于90%,出水TOC的浓度低于15 mg/L;HRT=1 d时,好氧反应器全程硝化能力达到最高,其容积负荷为0.418 kg N/(m^3·d);而HRT≥2 d时,能获得相对更为稳定的氮素转换效率。工艺系统最高能处理1/5尿液强度的生活废水,该条件下,系统TOC的去除率达94.3%,出水TOC浓度低于20 mg/L;系统氮素的全程硝化效率为90.6%,且反应器容积负荷较高为0.409 kg N/(m^3·d)。本文构建的两级MBfR工艺能较好地实现CELSS中特征性生活废水的有机物去除和氮素的有效转换,研究结果可为CELSS中生活废水微生物处理系统的设计和运行提供参考。
文摘尿液因其含有丰富的氮、磷、有机物等营养物质,被称为“废水中的黄金”,其如何处理废弃资源并实现高效资源化利用已成为环境工程领域科研人员关注的焦点。基于Web of Science数据库对“尿液废水”、“源分离尿液”等关键词进行检索分析、归纳总结,将目前处理源分离尿液废水的研究分为氮去除(回收)、磷回收、产电及其他等4个方面。进一步对其处理技术分析发现:1)氮回收主要通过吹脱、离子交换吸附、电化学等技术实现;2)磷回收则多以化学沉淀技术为主;3)基于生物电化学技术,尿液中有机化学能可回收电能,为其资源化利用提供新的途径。然而,由于尿液废水成分复杂、氮磷等污染物浓度高,现有单一技术难以实现其中多种物质或能量形式的同时处理与利用,且回收效果及成本仍不能满足实际应用要求,高效稳定的一体化源分离尿液废水处理技术仍需进一步深入研究。通过系统总结处理现状及研究进展,有利于加深对源分离尿液废水资源化处理技术应用的认识,具有一定的指导意义。
