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In Vietnam, an increase in construction activities together with the absence of recycling-oriented demolition techniques is giving rise to an alarming generation of construction and demolition waste. This study scrutinized the current state of building demolition approaches in Hanoi, Vietnam and evaluated the potential for the selective dismantling, or deconstruction, of reinforced-concrete (RC) houses. Site observations, direct measurement, and interviews were conducted to obtain information on technical, environmental, and economic characteristics of three residential housing sites, each representing a typical current demolition technique (manual, hybrid, and mechanical demolition). A selective dismantling site is proposed based on the collected survey data and published case studies. Our findings confirmed the unsustainability of RC-building demolition practices in Hanoi, which have an average reuse/recycling rate of roughly 3%. The application of selective dismantling will boost the recycling rate to a remarkable 90%, associated with a 55% decrease in greenhouse gas emissions. Even though selective dismantling is more time-consuming and therefore more costly, it results in double the resale value and an eight-fold decrease in disposal costs. The results of a sensitivity analysis indicate that increasing the current disposal fee will significantly improve the feasibility of selective dismantling, suggesting a need for stricter disposal charging mechanisms along with other interventions such as the development of recycling facilities to promote the introduction of this building removal alternative in Vietnam., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Increasing waste generation and the absence of a formal recycling industry are exacerbating the inadequacy of Construction and Demolition Waste (CDW) management in Hanoi, Vietnam. This study assesses potential CDW recycling in Hanoi by estimating the prospective supply of and demand for CDW recycling plants and evaluating their likely costs and benefits. Supply of concrete waste was calculated based on the weight-per-construction-area method whilst demand for recycled concrete aggregates (RCA) was determined by estimating the amount of aggregates for road construction in Hanoi from 2013 to 2017. Two potential models of CDW recycling plants were considered: a stationary plant and a mobile plant, with capacities of 1,000 and 360 tons/day, respectively. Our findings reveal that demand for RCA exceeds waste concrete supply, suggesting a promising market for RCA. Positive Net Present Value and Internal Rate of Return values of the stationary plant indicate its feasibility as an investment option. Meanwhile, the introduction of mobile recycling plants might require governmental intervention to internalize recycling positive externalities. Supporting policies might include a combination of a virgin material tax, green public procurement, and quality standard development., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

This study conducted a survey at 15 building construction and demolition sites in Hanoi, Vietnam in order to identify waste generation rates (WGR), composition, and current handling practices of construction and demolition waste (CDW). Waste quantification based on CDW layout, image analysis to identify CDW components, and face-to-face interviews with construction and demolition contractors to reveal CDW flows were performed. WGRs of 79.3 kg/m 2 and 1,030 kg/m 2 were determined in small- and large-scale construction sites, respectively, whilst WGRs at small and large demolition sites were 610 kg/m 2 and 318 kg/m 2 . The composition analysis identified soil, concrete, and brick as the major CDW components, consistent with building structures in Vietnam. The interviews discovered that merely 10% of total CDW flows was from recycled and reused CDW. Reuse and recycling rates were most significant for metal and were lower (in descending order) for brick, concrete, and soil. These findings raise a need for aggressive and integrated strategies to promote more sustainable CDW management in the country, including the development of recycled CDW product standards, policies that facilitate recycling, and more importantly, a sustainable business model for CDW recycling, for which future evaluations of economic feasibility are of great importance., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

From August 2007 until March 2008, we perfomed a detection and epidemiological analysis for Salmonella spp. in specimens collected from pork production chains to improve the quality of meat hygiene conditions in Hue, Vietnam. A total of 306 specimens were examined for Salmonella spp., aerobic bacterial counts and coliform. Seven serovars of Salmonella spp. were detected in retail pork, slaughterhouse carcasses and environmental specimens with the following detection rates: 32.8% of retail pork, 15.5% of slaughterhouse carcasses, 47.4% of floors, 38.1% of weighing bowls, 28.6% of cooking boards and 16.7% of tank water samples. Based on these results, we recommend that exhaustive sterilization, washing, routine bacteriological examinations and treatments at low temperature are performed in slaughterhouses, transportation facilities and retail stores.