在我国污泥减量化、稳定化的处理处置工程中，高干度污泥脱水装备的稳定运行是技术难点之一。近年来，集成了电渗透脱水和板框压滤原理的电渗透高干污泥脱水技术受到了广泛关注。本文以工程案例为基础，开展了电渗透高干脱水装置的优化运行，进行了技术经济分析与环境影响评价，以促进该技术的工程推广应用。本研究开展了污泥脱水工艺的对比分析。电渗透高干脱水技术不需药剂和热源，降低了运行成本。因此，与传统化学调理-板框压滤技术相比，电渗透高干脱水技术可节约48%的能源和药品，污泥体积减少25%左右；与常见热干化技术相比，达到同等焚烧要求的条件下可节约80%能耗，。本研究优化了实际电渗透高干脱水装置。参与调试和运行了北京市肖家河污水处理厂污泥干化项目，其中电渗透高干脱水设备处理规模100t/d。通过参数优化稳定了处理效果，泥饼含水率稳定且低于50 %，吨污泥能耗为87.6 kW?h。本研究基于调试数据开展了技术经济分析，确认了电渗透高干项目的投资价值。以肖家河项目为例，当污泥处置费由政府承担时，将在第9年收回成本，说明本技术具有较好的经济性。本研究采用生命周期评价分析的方法，比较了污泥脱水技术的环境影响。结果表明，与热干化技术相比，电渗透高干脱水污泥处理技术的各类中间点评价指标影响当量值要低13%~73%，具有更低的环境影响。最后利用综合分析方法，发现从技术性、经济性、环境性三个技术指标层面来看，热干化、电渗透高干以及板框压滤三个技术的最终得分分别为0.45，0.45和0.53。从技术性看，板框压滤和热干化作为成熟技术，得分较高；经济性方面来看，电渗透高干脱水技术有教明显的优势；从环境性指标来看，热干化和电渗透均相对板框压滤具有较大优势。
Among the techniques for sludge reduction and stabilization in wastewater treatment plants (WWTPs) in China, sludge dewatering and drying is one of the most difficult points. The electro-osmotic sludge dewatering to high dryness technology (EoSD) is a new type of sludge dewatering technology coupled electroosmotic dehydration and frame type dewatering. Due to its stable and good performance, EoSD has received wide attention. In this paper, we optimized equipments of EoSD and estimated its economic balance and environmental impacts, for the sake of its engineering application.We compared and estimated dewatering processes including EoSD, thermo drying and plate dewatering. We found that the electroosmotic high pressure drying technique does not require the addition of the agent and does not require a heat source, which can reduce the overall cost. If used for landfill disposal, electro-osmotic high-dry technology can save 48% of energy and drug consumption compared to "chemical conditioning + plate and frame filtration" technology, and the final sludge volume can be reduced by about 25%. If used for incineration, the technology can save about 80% less energy than thermal drying, and also reach incineration requirements.We joined the installation and optimization of a real EoSD project in Xiaojiahe Sewage Treatment Plant. There was an EoSD equipment with capacity of 100 t/d sludge dewatering. The sludge content of the treated sludge is stable and slightly below 50%, and the energy consumption per ton of sludge is about 87.6 kW?h.We conducted the calculation of economic benefits can be found in electroosmotic high pressure drying project has a certain investment value. In the case of the project in Beijing, for example, when the sludge disposal fee is borne by the government, the cost will be recovered in the 9th year, indicating that the technology has good economy.We carried on the life cycle evaluation to the technology, compared with the mechanical heat drying, the electro-osmotic high-dry dewatered sludge treatment technology has the lower environmental impact, the intermediate point evaluation index influence is 13% to 73% lower. Finally, with the comprehensive analysis method, it is found that in the aspects of technology, economic and environment, the final scrore of electroosmotic high-dry technology, heat-drying technology and plate and frame filtration are 0.45, 0.45 and 0.53. In the technical aspect, plate filter and heat-drying have high scores as a mature technology; in the economical aspects, the electro-osmotic has obvious advantages; in the environmental aspect, the heat-drying and electro-osmotic have certain advantages compares to the plate filter.
