Study on Rural Solid Waste Collection and Transportation Mode and Route Optimization Strategy in the Cold Regions of Northern China

Rural vitalization is a major strategy for reform and development of agriculture and rural areas in China,the key task of which is improving rural living environment.Imperfect rural solid waste(RSW)collection and transportation system exacerbates the pollution of RSW to rural living environment,while it has not been established and improved in the cold region of Northern China due to climate and economy.Through the analysis of the current situation of RSW source separation,collection,transportation and disposal in China,an RSW collection and transportation system suitable for the northern cold region was developed.Considering the low winter temperature in the northern cold region,different requirements for RSW collection,transportation and terminal disposal,scattered source points and single terminal disposal nodes in rural areas,the study focused on determining the number and location of transfer stations,established a model for transfer stations selection and RSW collection and transportation routes optimization for RSW collection and transportation system,and proposed the elite retention particle swarm optimization–genetic algorithm(ERPSO–GA).The rural area of Baiquan County was taken as a representative case,the collection and transportation scheme of which was given,and the feasibility of the scheme was clarified by simulation experiment.

Establishment and application of performance evaluation model for collection and transportation system of municipal solid waste

On the basis of analyzing the typical waste collection and transportation mode,the evaluation index system for performance of the waste collection and transportation system was proposed with three grades,which related to six factors,such as economic evaluation,high efficient evaluation,environmental impact assessment,resource evaluation,evaluation of security and emergency,evaluation of management and society. With the performance evaluation theory,the performance evaluation model of waste collection and transportation system was constructed,which quantified the grading standard of index and determined the index weight in analytic hierarchy process (AHP). After evaluating the waste collection and transportation system of the main districts of Chongqing city,the results show that the it has an excellent performance evaluation grade with very high performance level of three indices involving evaluation of management and society,environmental impact assessment,evaluation of security and emergency and quite low performance level of two indices that include high efficient evaluation and economic evaluation.

Informal Sector Solid Waste Collection and Recycling in Zaria, Nigeria

Management of solid wastes has become a critical issue for almost all the major cities in Nigeria. Although the responsibility for solid waste management remains primarily with the local government councils, several other stakeholders are playing significant roles in the system. In Zaria, the scavengers, waste pickers and collectors eke out a living by collecting waste and selling recyclable materials out of the urban solid wastes. The paper utilized data collected using questionnaire survey, in-depth discussion guides and open-ended interviews to examine the socio-economic characteristics, the functions, aspects of involvement of children, the working conditions and problems of waste collectors and pickers in Zaria. The paper found that the sector is the only means of solid waste collection in several sections of the town and is a source of livelihood for the poor. The activities help in realizing the aim of modern waste management, that is to move up the solid waste management hierarchy by reducing reliance on disposal and increasing recycling. In spite of these important functions, informal waste collection and recycling are associated with problems of unsanitary conditions and health risks to the communities and the waste collectors. Recommendations have been made to integrate the informal sector into the formal waste management by incorporating the employment needs of the urban poor and enhancing the efficiency of government in addressing the main problems.

Optimization of Planning Routes in Solid Waste Collection

This paper presents an optimization model for solving the planning problem of collection and transportation of solid waste in medium-sized cities. As final results, are expected to promote cost savings to the public coffers, as well as environmental benefits. The developed mathematical model is formulated as a problem of linear programming with mixed-integer variables and transcribed into software GAMS （general algebraic modeling system）. The practical application was tested using data collected in the central region of a Brazilian city with approximately 90,000 inhabitants. The deterministic model used allowed an optimal solution. It was found after inclusion of restrictions that eliminated the appearance of sub-routes. It was concluded that the optimal routes allow for a 38% reduction in total distance traveled, which can generate savings of $320.00 per day regarding maintenance and fuel trucks.

New application notion of pipeline transport——integrated in industry solid waste innocuous and efficient disposition

In order to solve transport problems of industry solid,firstly,a new applicationnotion of pipeline transport was presented,that is to say,combining pretreatment andtransport with disposal techniques of industry solid waste.Secondly,the integrated dis-posal and transport system for industry solid waste was introduced,in particular,the oper-ating principles,equipment set-up,key technology and technical parameters.Next,thispaper illustrated the application of this integrated system.Such as it can transport coalsludge with sufficiently high solids content(about 72%～77%)and high apparent viscosity(about 1 000～3 000 Pa.s)directly by pipeline having no use for water and addition agent.Generally,the transport distance is about 1 000 m.This system has been successfullyused in innocuous disposition and efficient utilization of other industrial byproducts or solidwastes,such as city sludge and paper making waste.The integrated system causes nopollution to the environment for its complete seal and realizes protecting the environment,conserving the energy,promoting the development of cycling economic.Finally,the paperdiscussed the research works that were needed for studying such pipeline transport sys-tem and narrates the relevant condition and application status.

Investigation of Inhabitants' Wishes on Classified Collection of Waste in Wanghua District of Fushun

In order to disclose present situation and problem of classified collection of municipal solid waste in Wanghua District of Fushun and ana- lyze its practicability, questionnaire was designed in this paper, random research was adopted in Wanghua District, and statistic analysis of investi- gation result was conducted. This investigation could provide basis for popularizing classified collection of municipal solid waste in the whole nation.

Critical Analysis of the Challenges of Solid Waste Management Initiatives in Keko Machungwa Informal Settlement, Dar es Salaam

Solid waste is inevitable because by nature every human activity generates a certain amount of solid waste. The rate of solid waste generated tends to increase with the increase in population. Despite existence of various efforts on solid waste collection, still the quantity of solid waste collected is small compared to the solid waste generated. The situation is even worse in unplanned settlements of developing countries, where, ineffective solid waste collection is contributed to by haphazard solid waste disposal and hence environmental pollution. Therefore, having an effective and efficient solid waste management system is a major challenge in cities of developing countries, and thus more consulted efforts are needed. This paper presents finding based on the study carried out in Keko Machungwa informal settlement in Dar es Salaam, Tanzania. The study explored challenges facing solid waste management initiatives in Keko Machungwa and recommended measures for improvement. Data for this study was collected through documentary review, household interviews, focus group discussions, physical observations and official interviews. The analysis reveals that solid waste generated in Keko Machungwa is 16 tones per day, among those, only 4.56 (less than 50%) are collected. About 11.44 tones of uncollected waste are illegally dumped into a seasonal stream and in different vacant lots hence causing blockage of the seasonal stream. Different groups engaged in solid waste collection are deterred by many challenges. The challenges include: lack of cooperation among the existing solid waste collection organs, inaccessibility in some places, low public participation, financial constraints and unwillingness of local community to pay for solid waste collection fees. The paper recommends four options on how solid waste management, particularly collection in Keko Machungwa can be enhanced. 1) Alliance among the existing organ, 2) placing dust-bins in different points within the settlement, 3) linking the fees of solid waste collection to other public services and 4) education and awareness creation campaigns accompanied by community stakeholder consultations.

Repercussions of Improved Municipal Solid Waste Management on Flood Risk Reduction: The Case of Dar es Salaam, Tanzania

Indisputably, flooding is one of the predicaments that have plagued many countries throughout the world. Consequently, Improvement of Municipal Solid Waste Management-(MSWM) has recently become one of the ways that is believed to help in reducing the impact of flooding. Following the fact that Dar es Salaam, the commercial capital, has nearly 5 million inhabitants and several of the wards are in flood-prone areas, the City authorities introduced new models of MSWM by incorporating public-private partnership as a deliberate action envisioned to improve MSWM. Nevertheless, the extent to which the strategy is effective in minimizing flood risks had not been adequately researched, which prompted a need to conduct a study. Specifically, the study sought to: assess the current practice of SWM in the settlement;examine the extent to which flood risk had been reduced given the application of the new models of SWM. This is primarily a case study which used Keko Machungwa in Dar es Salaam as the study area. Different forms of data collections tools were used for instance interviews of households and officials, photographs, spatial data etc. The findings indicated that Jukwaa la Wanawake in Keko Machungwa, a newly emerged community-driven organization was doing a fairly good job in handling SWM. This social entity was capable of collecting 40 tons of solid wastes per week and arranged for transportation. Overall, there was a marked decrease in haphazard dumping within the settlement. Despite the improvement, however, flooding was still persistent and was an alarming challenge. To that effect, this study recommends that improving solid waste collection could help overcome the problem of flooding particularly if integrated with other initiatives which include 1) Investment in robust flood control structures;2) Adherence to Urban planning and disaster management policies which prohibit development in hazardous areas, an instance of which being demolishing the existing building structures located in the water way in Keko Machungwa and;3) Initiate large scale flood risk reduction settlement schemes.

Robust Optimization of Municipal Solid Waste Collection and Transportation with Uncertain Waste Output: A Case Study

Garbage collection is an important issue in urban environmental management.With the increased awareness of urban residents regarding safety,environmental protection,and health in recent years,it is necessary to logically organize municipal solid waste collection and transportation routes while also considering economic and social benefits.This article focuses on the optimization of the waste transportation routes of garbage trucks.With the objective of minimizing transportation costs and maximizing resident satisfaction,we establish a robust optimization model for the multi-trip collection and transportation of municipal solid waste in an uncertain environment.Resident satisfaction is defined as the penalty cost against a time window constraint.The Bertsimas robust optimization method is applied to characterize the uncertainty,and the decision-making scheme of the receiving route is used to adapt to waste volume changes.We conduct a case study based on real-world data for municipal solid waste collection and transportation in the Dongcheng District of Beijing,China.The solution is validated using the CPLEX program,and the validity of the model is verified.In addition,a sensitivity analysis of related parameters is conducted to study the impacts of variations in work hour limits and time windows on the total cost and service levels,as well as their relationships with the level of robustness.This could help decision-makers make reasonable choices based on actual conditions and to balance reductions in total cost with service level improvements.

Energy-Efficient Multi-Trip Routing for Municipal Solid Waste Collection by Contribution-Based Adaptive Particle Swarm Optimization

Waste collection is an important part of waste management system.Transportation costs and carbon emissions can be greatly reduced by proper vehicle routing.Meanwhile,each vehicle can work again after achieving its capacity limit and unloading the waste.For this,an energy-efficient multi-trip vehicle routing model is established for municipal solid waste collection,which incorporates practical factors like the limited capacity,maximum working hours,and multiple trips of each vehicle.Considering both economy and environment,fixed costs,fuel costs,and carbon emission costs are minimized together.To solve the formulated model effectively,contribution-based adaptive particle swarm optimization is proposed.Four strategies named greedy learning,multi-operator learning,exploring learning,and exploiting learning are specifically designed with their own searching priorities.By assessing the contribution of each learning strategy during the process of evolution,an appropriate one is selected and assigned to each individual adaptively to improve the searching efficiency of the algorithm.Moreover,an improved local search operator is performed on the trips with the largest number of waste sites so that both the exploiting ability and the convergence accuracy of the algorithm are improved.Performance of the proposed algorithm is tested on ten waste collection instances,which include one real-world case derived from the Green Ring Company of Jiangbei New District,Nanjing,China,and nine synthetic instances with increasing scales generated from the commonly-used capacitated vehicle routing problem benchmark datasets.Comparisons with five state-of-the-art algorithms show that the proposed algorithm can obtain a solution with a higher accuracy for the constructed model.

Some Aspects of Waste Management of Ukraine

The development of waste management can be considered in some way dictates of time. Ukraine has unique conditions of the secondary usage of natural resources, which is particularly important given to the increasing generation of waste and its progressive accumulation. The relevant provisions relate to the industrial sector as well as areas of consumption. However, for most of recyclable materials is still low. The formation of market relations in Ukraine contributed to enhance this process and relevant field of entrepreneurship. Now the formation of a separate segment is taking place. The state and the perspectives of the development of collection, accumulation and recycling of waste stream have been analyzed in the article. Conceptual position of the legislative regulation of this field is defined. The ways of improving the legal support of secondary raw materials have been defined. The peculiarities of waste management of Ukraine are considered.

生活垃圾收运环节温室气体排放量核算方法研究

科学合理的碳核算方法是支持碳达峰碳中和的关键,生活垃圾分类下收运环节温室气体排放量的系统性核算方法有待完善.为了科学核算分类下生活垃圾收运环节温室气体排放,该研究依据《IPCC 2006年国家温室气体清单指南2019修订版》及《温室气体协议》,开展了生活垃圾收运环节核算范围的确定、温室气体排放源和排放种类的识别及核算模型构建.结果表明:生活垃圾收运环节核算范围包括投放点、暂存点、中转站以及处置点4个核算单元,排放源包括移动源、固定源和工艺/过程排放,移动源为收运车辆用电隐含排放CO_(2)以及燃料燃烧排放的CO_(2)、CH4和N_(2)O,固定源为中转站用能设施隐含排放的CO_(2),工艺/过程排放为收运车辆尾气净化消耗催化剂产生的CO_(2).同时构建了温室气体排放核算模型,对北京市顺义区生活垃圾收运环节碳排放当量进行核算,结果显示分类后的厨余垃圾和其他垃圾收运环节温室气体排放量存在差异,其中单位厨余垃圾温室气体排放量(以CO_(2)当量计)为24.78 kg/t,单位其他垃圾温室气体排放量为18.77 kg/t.研究显示,生活垃圾装/卸载过程是产生温室气体的主要排放源,其排放量均占比在50%以上.该研究对生活垃圾分类下的收运过程,建立了可拆分、可组合、模块化的核算单元,可为我国各城市生活垃圾收运环节温室气体排放量核算提供理论支撑.

基于混合遗传算法的皮革产业固废运输路径优化研究

皮革产业形成的固废含有部分对环境、人体等存在一定负面影响的物质,这类固废的运输方式极为关键。本文构建了一种基本的皮革产业固废运输路径模型,通过引入混合遗传算法对该模型中的皮革产业固废运输路径进行优化,以案例的形式对这一模型的可行性进行验证,旨在为皮革产业废弃物的运输工作提供借鉴。

分类收集对我国城市生活垃圾处理处置的影响探析

城市生活垃圾分类收集是实现生活垃圾高效资源化和无害化处理的必然途径。垃圾分类制度的正式实行,使城市生活垃圾收运模式得到了优化,节约了填埋场库容,降低了填埋场失稳风险和焚烧烟气中的重金属含量。我国于2019年在全国范围内实施生活垃圾分类制度,全面推进了城市生活垃圾分类收集工作。分类收集对我国城市生活垃圾处理处置所产生的影响引起了业界广泛关注。通过文献调研,总结和分析了我国城市生活垃圾分类收集的现状及分类收集对生活垃圾不同处理处置方式的影响研究现状及进展,以期为我国更好地规划和管理生活垃圾处理处置及相关研究提供参考。

增强型集气覆盖层闭气能力影响因素及优化布置

为了实现我国生活垃圾填埋场的高效集气,消除填埋气无序逸散造成的环境污染及人身安全问题,提出由HDPE土工膜、膜下集气管和土质调节层构成的增强型集气覆盖层(EGCC)结构.采用Geo-studio软件中的Air/W模块,分析增强型集气覆盖层的闭气效果及其影响因素.结果表明,土质调节层的固有渗透率、膜下集气管的抽气压力和单层填埋垃圾的厚度是影响增强型集气覆盖层闭气效果的3个主要因素.膜下最大气压随着土质调节层的固有渗透率的降低、膜下集气管抽气压力的提高和单层填埋垃圾厚度的提高而增大.提出基于土质调节层的固有渗透率和膜下集气管抽气压力的膜下集气管布置间距估算公式,建议优先选用当地容易获得的中砂或更粗的土料作为土质调节层.在深圳下坪填埋场采用增强型集气覆盖层并结合集气井技术后,2014—2019年期间填埋气收集量提升7倍以上,收集率由不到30%提升至超过90%.

垃圾分类背景下县域城乡生活垃圾处理体系建设的实践探索

在垃圾分类的背景下,采取实地考察、采样分析和调查研究等形式,对近年来滕州市城乡生活垃圾处理体系建设的实践探索及工作经验进行研究。分析了当前生活垃圾分类收运体系发展滞后、垃圾末端处置设施存在短板、建筑垃圾资源化利用率整体偏低等问题。同时,结合实际提出全面打造最优垃圾分类收运链条、建设新型环保固废循环经济静脉产业园、探索推行建筑垃圾“一体化”运作等对策和建议。

关于生活垃圾分类的市场化研究

生活垃圾分类是改善生态环境,提升居民文明素养的有效平台,开展生活垃圾分类具有深远意义。对生活垃圾分类收集市场产业化运作模式进行了分析,以问题为导向,建立统筹谋划,靶向失策,系统改革的工作思路,对城市开展生活垃圾分类收集市场化发展提供了理论依据。

进水管设置角度对圆形循环水养殖池自清洗能力的影响

为了提高圆形养殖池的自清洗能力,本研究系统开展了污物汇集试验和流场测量试验。实验针对圆形养殖池双管贴壁进水模式,共设计9个不同的角度工况。利用设置在养殖池正上方的相机记录不同工况下污物的汇集过程,通过分析污物的运动过程以及池内剩余的污物量,量化进水管设置角度对养殖池内污物汇集过程以及自清洗能力的影响。利用PIV技术测量了不同工况下距离池底1、2、10、19 cm(底层、近底层、中层、上层)水层的流场,通过分析流态以及水阻力系数Ct、速度均匀系数DU50等养殖池水动力参数,阐明进水管设置角度对养殖池内污物汇集以及自清洗能力的影响机制。结果显示,进水管设置角度明显影响养殖池的自清洗能力,自清洗能力随着进水管设置角度的增大先增大后减小,在45°~50°工况时养殖池自清洗能力最优;进水管设置角度通过影响底层流速大小和流态影响养殖池的自清洗能力,流速大小决定污物能否起动,流态决定污物能否汇集至出水口。因此,在实际循环水养殖生产中建议将与本研究中类似的养殖池的进水管角度设置为45°~50°,以提高养殖池的自清洗能力,提升循环水养殖系统的综合性能。

长沙市餐厨垃圾收运管理系统研究与实践

餐厨垃圾收运是实现其资源化和无害化的关键环节,虽然已经研发很多新型收运系统,但是仍然存在源头数据获取准确率低的问题。针对这个问题,介绍一种基于App的餐厨垃圾收运管理方法,并以长沙市餐厨项目为例,验证该方法的实用性及其在餐厨垃圾全覆盖收运中的重要作用。该方法为餐厨垃圾收运提供了新的管理模式,能够显著提高收运数据获取的准确性,具有广阔的应用前景。

固废收运企业的环保信息化管理系统设计与应用

为响应“无废城市”建设,提高固废精细化、信息化管理水平,以某一般工业固废收运企业的环保信息化系统建设为例,分析该系统的功能和特点,阐述信息化在固废收运企业环保管理中的有效促进作用。系统实际应用结果表明,信息化能够有效促进固废收运企业的环保管理,显著提升一般固废的资源化利用效率,实现一般固废的集中治理,优化市场服务和营商环境,助力企业绿色转型。