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The shift of discussions on wastewater management to realize a circular water economy requires rethinking of how the existing systems are managed. The collection system, a physical infrastructure that collects and transports wastewater, is often overlooked in innovation studies in wastewater management. Hence, a review of the collection system is required to realize overlooked innovation points, especially those of its functions and configurations. In this paper, we highlight the possibility of the collection system to contribute to wastewater management, not only to collect and transport wastewater, but to treat wastewater through enhancing sewer self-purification. To realize this, a systems analysis of the forms and functions of the collection system was first conducted to see how the collection system supports different wastewater management systems. It was found that emphasis on the collection system's function to treat wastewater is beneficial because of the transition of wastewater management towards a circular water economy. Second, a scenario analysis of applying enhanced sewer self-purification technologies was conducted to determine communities which would most benefit from using the collection system to treat wastewater. The findings highlight that communities with as much as 100 cap ha-1, typical of urban peripheries, could have their pollutant load reduced to about half if the pipe length per capita is 5 m. It was seen in this study that while the collection system supports wastewater management by functioning to collect and transport wastewater, it can further be elevated into a treatment technology within appropriate localities and thus, contribute to a circular water economy.

Data about the generation of empty pesticide containers (EPC) is scarce, even in countries where an EPC collection system is applied. In most cases, data refers to the total amount of EPC collected, which is lower than EPC generated depending on the extent of application of the collection project. Moreover, results are not correlated to the kind of crops, area and number of farmers involved, making impossible to use them elsewhere. This study aims at estimating EPC generation indices. It focuses on the indirect assessment of EPC generation based on information given by the agronomists of agricultural supplies stores and agricultural cooperatives (stakeholders) consulting farmers. For the study area (Pella prefecture in Greece), EPC waste production was estimated for arable crops, fruits and vegetables and it was found to range from 0.9 to 35.3 pieces/hectare depending on the crop type. The weight of empty plastic pesticide containers (EPPCweight) indices were calculated at 0.97 kg/ha and 4.36 kg/farmer/year which are close to the scarce available literature data. These results can be the basis for the design of an EPC management program in areas where data of this type of wastes is lacking. Other results of this survey indicate that stakeholders (depending on their capacity) could be motivated to organize and operate EPC collection stations as well as to help farmers to comply with the national management plan. Based on the above findings, three alternative scenarios for EPC management are proposed to provide a basis for designing an applicable regional EPC management program.

This paper analyses the food waste collection and transportation (CT) system in a pilot project in Suzhou by using a novel performance evaluation method. The method employed to conduct this analysis involves a unified performance evaluation index containing qualitative and quantitative indicators applied to data from Suzhou City. Two major inefficiencies were identified: a) low system efficiency due to insufficient processing capacity of commercial food waste facilities; and b) low waste resource utilization due to low efficiency of manual sorting. The performance evaluation indicated that the pilot project collection system's strong points included strong economics, low environmental impact and low social impact. This study also shows that Suzhou's integrated system has developed a comprehensive body of laws and clarified regulatory responsibilities for each of the various government departments to solve the problems of commercial food waste management. Based on Suzhou's experience, perspectives and lessons can be drawn for other cities and areas where food waste management systems are in the planning stage, or are encountering operational problems.