天津市城市生活垃圾物理组成及影响因素分析

对天津市市内六区、环城四区和滨海新区的生活垃圾进行了调查,分析了影响城市生活垃圾物理组成变化的主要因素。     

长期职业暴露于市政固体垃圾与中毒性神经病的进展：营养补充与补充替代医学在化学预防中的前景

Achieving effective municipal solid waste （MSW） management remains a major challenge and waste generation and accumulation continue to constitute important environmental and public health concern, particularly in most developing countries. Although the general population is at risk of adverse health consequences and hazards associated with exposure to MSW, the waste management workers （WMWs） are the most vulnerable because of their direct involvement in the disposal of waste, with increasing evidence of work-related health and safety risks among these individuals. Among the numerous work-related health hazards prevalent in WMWs, development of toxic neuropathies following chronic occupational exposure remains poorly recognized. However, the risk or predisposition to toxic neuropathies is becoming evident considering the increasing recognition of large amount of neurotoxic heavy metals and hazardous industrial materials present in MSW in mostparts of the world. The present review seeks to draw attention to the continuous vulnerability of the WMWs to developing toxic neuropathies. This is aimed at facilitating conscious efforts by relevant governmental and non- governmental agencies towards promoting risk reduction and ensuring adequate protection against possible toxic polyneuropathies associated with occupational exposure to solid wastes. While continuous education of the WMWs on the need for adequate compliance to safety regulations and practice remains sacrosanct towards achieving significant reduction in toxic neuropathies and related adverse health consequences of waste handling, it is also our intention in this review to underscore the possible relevance of nutrient supplementation and alternative medicines in chemoprevention.     

In search of legitimacy – registered nurses’ experience of providing palliative care in a municipal context

Background: The palliative care approach was originally developed for hospice care and for persons with cancer diseases, but has gradually expanded to embrace other contexts and people of all ages, with various life‐threatening diseases. The palliative care concept thus also applies to older people and the context of municipal care, where Registered Nurses (RNs) hold key care provision positions. The municipal context is not, however, focused primarily on advanced nursing care, and it is important to highlight RNs’ prerequisites for care provision. Aim: The study’s aim was to describe RNs’ experience of providing palliative care for older people in a municipal context. Data were collected through focus group discussions with 20 RNs from four different municipalities in southern Sweden and were analysed using conventional content analysis. Findings: The results showed that the nurses experienced that it was they who cushioned the effects of unclear responsibilities between different organizations, but had limited legitimacy in the municipal context and in relation to other care providers. The results also showed that nurses lacked proper support and prerequisites for providing high‐quality palliative care to older dying patients. Conclusion: The results pinpoint the importance of increased acknowledgement of nurses’ knowledge and skills and a critical view on the effects of moving towards an organization composed of different consultants, which can lead to even more unclear responsibility for nursing care provision.     

Applying Mixture of Municipal Incinerator Bottom Ash and Sewage Sludge Ash for Ceramic Tile Manufacturing

Municipal incinerator bottom ash (MIBA) and sewage sludge ash (SSA) are secondary wastes produced from municipal incinerators. Landfills, disposal at sea, and agricultural use have been the major outlets for these secondary wastes. As global emphasis on sustainability arises, many have called for an increasing reuse of waste materials as valuable resources. In this study, MIBA and SSA were mixed with clay for ceramic tile manufacturing in this study. Raw materials firstly went through TCLP (Toxicity Characteristic Leaching Procedure) to ensure their feasibility for reuse. From scanning electron microscopy (SEM), clay’s smooth surface was contrasted with the porous surface of MIBA and SSA, which led to a higher water requirement for the mixing. Specimens with five MIBA mix percentages of 0%, 5%, 10%, 15%, and 20% (wt) and three SSA mix percentages of 0%, 10%, and 20% (wt) were made to compare how the two waste materials affected the quality of the final product and to what extent. Shrinkage tests showed that MIBA and SSA contributed oppositely to tile shrinkage, as more MIBA reduced tile shrinkage, while more SSA encouraged tile shrinkage. However, as the kiln temperature reached 1150 °C, the SiO2-rich SSA adversely reduced the shrinkage due to the glass phase that formed to expand the tile instead. Both MIBA and SSA increased water tile absorption and reduced its bending strength and wear resistance. Increasing the kiln temperature could effectively improve the water absorption, bending strength, and wear resistance of high MIBA and SSA mixes, as SEM showed a more compact structure at higher temperatures. However, when the temperature reached 1100 °C, more pores appeared and seemingly exhausted the benefit brought by the higher temperature. Complex interactions between kiln temperature and MIBA/SSA mix percentage bring unpredictable performance of tile shrinkage, bending strength, and water absorption, which makes it very challenging to create a sample meeting all the specification requirements. We conclude that a mix with up to 20% of SSA and 5% of MIBA could result in quality tiles meeting the requirements for interior or exterior flooring applications when the kiln temperature is carefully controlled.     

Effect of Flue Gases’ Corrosive Components on the Degradation Process of Evaporator Tubes

Corrosion of boiler tubes remains an operational and economic limitation in municipal waste power plants. The understanding of the nature, mechanism, and related factors can help reduce the degradation process caused by corrosion. The chlorine content in the fuel has a significant effect on the production of gaseous components (e.g., HCl) and condensed phases on the chloride base. This study aimed to analyze the effects of flue gases on the outer surface and saturated steam on the inner surface of the evaporator tube. The influence of gaseous chlorides and sulfates or their deposits on the course and intensity of corrosion was observed. The salt melts reacted with the steel surface facing the flue gas flow and increased the thickness of the oxide layer up to a maximum of 30 mm. On the surface not facing the flue gas flow, they disrupted the corrosive layer, reduced its adhesion, and exposed the metal surface. Beneath the massive deposits, a local overheating of the inner surface of the evaporator tubes occurred, which resulted in the release of the protective magnetite layer from the surface. Ash deposits reduce the boiler’s thermal efficiency because they act as a thermal resistor for heat transfer between the flue gases and the working medium in the pipes. The effect of insufficient feedwater treatment was evinced in the presence of mineral salts in the corrosion layer on the inner surface of the tube.     

上海市生活垃圾处理处置现状与对策

分析上海生活垃圾产生量、组成、特性和处理处置现状,探讨其中存在问题,提出解决对策。