Paint Sludge Reuse

http://deepblue.lib.umich.edu/bitstream/2027.42/106047/1/ME589F13_881-7_Paint Sludge Reuse_Public Summary.pd

Eco-Efficiency of Drinking Water Treatment

Problem statement:In the water treatment processes, the chemicals (aluminum sulfate AS, chlorine, and polyelectrolyte) are required in the different steps of treatment (coagulation, flocculation, settling, disinfection…). The chemicals residues can affect the human healthy and the environment. The treatment process produces sludge according to the level of the water turbidity. However, the sludge management increases the monitoring expenses. Moreover, this water treatment sub-product constitutes a threat for the environment and the downstream water users.Approach:In this study, the effectiveness of chemicals uses and sludge reuse was evaluatedin order to find optimal operational conditions and reduce its residues. The influence of the chemicals consumption on the cost of treated water was also studied. A set of jar test experiments was conducted to find the sludge and aluminum sulfate dosages in order to improve the produced water quality for different turbidity levels. Results: Results demonstrated that the consumption of chemicals could be reduced by 10 to 15%. The sludge reuse improve the water quality and decrease the AS consumption by 50 to 60%. The turbidity removal is increasing and the aluminum residues is decreasing by 50%. Conclusions/Recommendations:Results show that the sludge reuse plays a very important role in reducing the aluminum sulfate dosage, improving the treated water quality and reducing water cost. The AS control and modeling reduce the chemicals consumption. This approach contributes in preserving the environment and opens income-earning opportunities for local population by promoting local products made from water treatment sludge

Enhancing a Transition to a Circular Economy in the Water Sector: The EU Project WIDER UPTAKE

Wastewater treatment plants (WWTPs) require an urgent transition from a linear to a circular economy operation/design concept with a consequent resource recovery and more sustainable waste management. Natural resources have to be preserved, and wastes have to become an opportunity for recovering resources and materials (water reuse, energy, sludge reuse). However, the transition toward a circular economy is a complex and long process due to the existence of technical, economic, social and regulatory barriers. These existing barriers are critical challenges for a modern and sustainable WWTP concept. The recovery of resources must be considered a strategic target from the earliest process-design phase. In this context, the European Union’s Horizon 2020 project “Achieving wider uptake of water-smart solutions—WIDER UPTAKE” aims to overcome the existing barriers (technological, regulatory, organizational, social and economic) toward the transition from a linear to a circular economy model for WWTPs. This study is aimed at increasing the awareness of the existing barriers to a circular economy and summarizes the key contributions of the WIDER UPTAKE project in terms of water reuse, sludge reuse and nutrient recovery

When faecal sludge reuse doesn’t work: a look at access for the poorest and people with disabilities in urban Malawi

Reusing faecal sludge to generate value has the potential to contribute towards solving the issue of long term sanitation solutions in cities across Sub-Saharan Africa. This research was conducted to evaluate the potential for faecal sludge reuse in Malawi, and the difficulties and challenges to existing attempts at reuse in a city. We conducted 65 semi-structured interviews in a city of Malawi. The results show that two main approaches exist currently: The implementation of Skyloos as above ground household toilets which provide compost; and a central disposal site from which compost is illegally harvested. Both existing approaches to faecal sludge management and reuse were found to be inaccessible and not working when implemented for the poorest and people with disabilities

Inhibeeriva ja raskestilaguneva reovee töötlemise uuringud

Väitekirja elektrooniline versioon ei sisalda publikatsiooneMeie kodudes tekib iga päev olmereovesi, mis sisaldab erinevaid saasteaineid. See suunatakse reoveepuhastisse, kus mikroorganismid tarbivad reovees sisalduvaid saasteaineid oma elutegevuse käigus. Sageli jõuab olmereoveepuhastitesse ka tööstuslik reovesi, mis võib sisaldada reovett puhastavate mikroorganismide ainevahetust pärssivaid saasteaineid, põhjustades puhastusprotsesside inhibitsioone. Seeläbi väheneb reovee puhastamise efektiivsus ning saasteained võivad jõuda keskkonda. Reovee inhibeerivate omaduste vähendamiseks on saadaval erinevad tehnoloogiad, kuid igale põhilisele aktiivmudaprotsessile rakendatavat ja usaldusväärset metoodikat inhibeeriva mõju hindamiseks ei leitud. Lisaks võib tööstusliku päritoluga reovesi sisaldada bioloogiliselt mittelagunevaid orgaanilisi ühendeid ning seetõttu vajada aktiivmudaprotsessist tõhusamate puhastustehnoloogiate rakendamist. Üheks selliseks protsessiks on näiteks Fenton, mis põhineb keemilisel oksüdeerimisel. Fentoni protsessi kasutamist limiteerib suurest kemikaalitarbest tulenev opereerimise kõrge hind ning ohtliku rauarikka jääkmuda teke. Selle doktoritööga lahendati kolm olulist probleemi raskestilaguneva ja inhibeeriva reovee puhastamisel. Esiteks, leiti optimaalsed tingimused inhibitsioonitestidele hindamaks reovee või ohtliku ühendi mõju aktiivmudaprotsessidele, millele usaldusväärsed standardmetoodikad puudusid – aktiivmuda tõhustatud bioloogilisele fosforiärastusele ning lämmastikuärastuse teisele etapile, denitrifikatsioonile. Inhibitsiooniteste rakendatakse reovee sobivuse hindamiseks töötlemiseks aktiivmudaprotsessiga või reoveepuhastile probleeme tekitava sissevoolu päritolu tuvastamiseks. Teiseks, testiti aktiivmuda- ja füüsikalis-keemiliste protsesside kombinatsioone nelja erineva keeruliste omadustega reovee puhastamiseks arvestas inhibitsiooni ja biolagundatavuse testidest saadavad teavet. Kombineeritud töötlemine suurendas keeruliste omadustega reovee puhastamise tõhusust ja vähendas puhastamise hinda. Kolmandaks, Fentoni protsessi opereerimist muudeti viisil, milles ei teki rauarikast jääkmuda ja vähenes kemikaalikulu ning seeläbi ka opereerimise hind.Municipal wastewater containing different pollutants is produced in our homes every day. It is subjected to wastewater treatment plant (WWTP), where microorganisms consume these pollutants. Industrial wastewater containing inhibitory substances is frequently subjected to municipal WWTP-s, which causes the inhibition of wastewater treatment processes. Consequently, wastewater treatment efficiency decreases and pollutants may be subjected to the water bodies. Different technologies are available for inhibition removal, but there were no applicable and reliable methods found for all main wastewater treatment processes. Additionally, industrial wastewater may contain biorefractory organic substances and thereby require application of advanced treatment methods, e.g. the Fenton process. The Fenton process is an advanced oxidation process which application is limited by high operational costs due to high chemical consumption and production of hazardous ferric waste sludge. Three significant problems of inhibitory and recalcitrant wastewater treatment were solved with this thesis. Firstly, optimal conditions for inhibition tests were found to estimate the impact of wastewater or inhibitory substance on wastewater treatment processes for which no reliable standard methods were found – activated sludge enhanced biological phosphorus removal and for the second step of nitrogen removal, denitrification. Inhibition tests are applied to estimate the feasibility of activated sludge processes to treat a certain wastewater and to identify the origin of wastewater causing wastewater treatment problems. Secondly, combined activated sludge and physical-chemical treatment of complex wastewater was tested considering results from preliminary inhibition and biodegradability studies, which increased the treatment efficiency and reduced cost of complex wastewater treatment. Thirdly, operation the Fenton process was modified to reduce the production of ferric waste sludge and consumption for chemicals.https://www.ester.ee/record=b542144

Constructed wetlands for winery wastewater treatment: a comparative Life Cycle Assessment

A Life Cycle Assessment was carried out in order to assess the environmental performance of constructed wetland systems for winery wastewater treatment. In particular, six scenarios which included the most common winery wastewater treatment and management options in South-Western Europe, namely third-party management and activated sludge systems, were compared. Results showed that the constructed wetland scenarios were the most environmentally friendly alternatives, while the third-party management was the worst scenario followed by the activated sludge systems. Specifically, the potential environmental impacts of the constructed wetlands scenarios were 1.5–180 and 1–10 times lower compared to those generated by the third-party and activated sludge scenarios, respectively. Thus, under the considered circumstances, constructed wetlands showed to be an environmentally friendly technology which helps reducing environmental impacts associated with winery wastewater treatment by treating winery waste on-site with low energy and chemicals consumption.Peer ReviewedPostprint (author's final draft

A review of the financial value of faecal sludge reuse in low-income countries

Faecal sludge reuse could promote responsible waste management and alleviate resource shortages. However, for this reuse to be carried out at scale, it needs to be financially viable. This paper reviews the financial values of resource recovery from 112 data points from 43 publications from academic and grey literature. The results found 65% of the existing literature is projected rather than being based on observed data from products in practice, with limited studies providing actual experiences of revenue in practice. Some of the estimates of the potential value were ten times those observed in data from operating businesses. Reasons for this include pricing of products against unrealistic competitors, for example, pricing briquettes against diesel fuel, or difficulties in marketing or regulation of products in practice. The most common form of reuse in practice is agricultural composting, which is also the lowest value product. Few cases were able to achieve more than $5/person/year from sludge reuse, therefore other drivers are needed to promote proper human waste disposal, including the health and dignity of citizens, but which are not easily monetised. Certification and recognition of product safety can improve the perception of value and products. Resource recovery has a limited role in the financial viability of providing Circular Economy sanitation in low-income countries. Instead, there is a need to focus on supportive policies and subsidies enabling the transition towards a Circular Economy supporting environmental quality, ecological health and human health

Quantitative microbial risk assessment of wastewater and faecal sludge reuse in Ghana

The probabilistic health risks of rotavirus and Ascaris infections associated with different scenarios of diluted wastewater and faecal sludge agricultural reuse in Ghana were estimated based on the Quantitative Microbial Risk Assessment (QMRA) approach. The annual risks of rotavirus and Ascaris infections associated with diluted wastewater reuse scenarios were 10-2 and 10-3 to 10-4 respectively compared with the WHO tolerable health risk of 10-4 per person per year. The risk of Ascaris infection for the different scenarios of faecal sludge reuse ranged from 10-4 to 10-2 while it was <10-14 to 10-1 for rotavirus infections per single exposure. The treatment of faecal sludge significantly reduced the risk of rotavirus infections but had less effect on the reduction of Ascaris infections. It is stressed that the estimated risks of infection need to be validated against follow-up data obtained from epidemiological investigations coupled with studies on different health risk barriers