The remarkable development of sanitation in Morocco has inevitably led to the production of sludge generated from wastewater treatment plants in increasing quantities. Consequently, the problem of sludge management becomes persistent and worrying.
The aim of this paper was to contribute to the study of sewage sludge management issue in Morocco by identifying the various constraints hampering the sustainable disposal and/or recovery of municipal sewage sludge and drawing up rec-ommendations for the decision-makers. Moreover, in the context of improving by learning from best practices and seeking common solutions regarding this problematic, benchmarking with other countries has been conducted as well.
To carry out this study, a methodological approach was defined based on bibliographic research, surveys, interviews and benchmarking.
The constraints hampering the sustainable management of sludge are numerous and complex, they have not been tech-nical and environmental but also a regulatory, institutional-organizational and economic-financial nature yet. Therefore, municipalities, government and academia ideally would be encouraged to participate in the decision-making process re-garding the management of sewage sludge. Technical solutions, when coupled with stakeholder participation, can lead to policy implementation with a higher chance of improving the present situation.
In the case of Morocco, when comparing with others sludge recovery and disposal routes, land application (reuse in ag-riculture, silviculture and rehabilitation of degraded soils) remains the most environmentally friendly option, as well as a sustainable and economically viable solution.
In environmental matrices there are mixtures of parent drug and its metabolites. The majority of research is focused on the biological activity and toxic effect of diclofenac (DCF), there is little research on the biological activity of DCF metabolites and their mixtures. The study focused on the assessment of the biological impact of DCF, its metabolites 4’-hydroxydiclofenac (4’-OHDCF) and 5-hydroxydiclofenac (5-OHDCF) and their mixtures on E. coli strains. The biological effects of tested chemicals were evaluated using the following: E. coli K-12 cells viability assay, the inhibition of bacteria culture growth, ROS (reactive oxygene species) generation and glutathione (GSH) content estimation. Moreover, we examined the influence of the mixture of DCF with caffeic acid (CA) on E. coli cells viability. Our results showed the strongest impact of the mixtures of DCF with 4’-OHDCF and 5-OHDCF on E. coli SM biosensor strains in comparison to parent chemicals. Similar results were obtained in viability test, where we noticed the highest reduction in E. coli cell viability after bacteria incubation with the mixtures of DCF with 4’-OHDCF and 5-OHDCF. Similarly, these mixtures strongly inhibited the growth of E. coli culture. We also found synergistic effect of caffeic acid in combination with DCF on E. coli cells viability. After bacteria treatment with the mixture of DCF and its metabolites we also noted the strongest amount of ROS generation and GSH depletion in E. coli culture. It suggests that oxidative stress is the most important mechanism underlying the activity of DCF and its metabolites.
This work aims to evaluate the treated wastewater from the activated sludge treatment plant in the City of Sidi Bel Ab-bes (North-Western Algeria) which is required for reuse in irrigation. The control of irrigated areas downstream is done based on a pedological study. Physico-chemical analysis such as (pH, BOD5, COD and SS) indicate results in Algerian and international standards required by the WHO. The Sodium Adsorption Ratio and Electrical Conductivity values of the treated wastewater belong to the C3-S1 class. The treated wastewater has a fairly good microbiological quality that meets Algerian standards. The helminth eggs are practically absent. The concentrations of heavy metals are much lower than the limits prescribed in the Algerian decrees. Therefore, the overall processing plant efficiency is satisfactory and has the char-acteristics of a good treated water quality for reuse in the field of irrigation while protecting the environment. The pedolo-gical study of the soil samples shows that the most dominant fraction is undeveloped calcimagnetic. The planned irrigation plain covers an area of about two thousand hectares. Depending on the crops to irrigate; the development and nature of the necessary or recommended improvements, the proposed irrigation perimeter could be classified into five categories in which only three categories are irrigable. Water projects have been proposed to ensure the irrigation of three subdivided sectors.
Anaerobic digestion (AD) is an adequate alternative to treat wastewater generated from fruit and vegetable processing (FVWW); likewise, in recent years, artificial wetlands (AWs) have been applied as a post-treatment process for anaerobi-cally pre-treated wastewater. The objective of this work was to design a sustainable treatment system for FVWW composed of upflow anaerobic reactors (UASB) with phase separation and an AW system that receive the anaerobically pretreated effluent. Using the design methodologies for the UASB reactors and artificial wetlands with sub-surface flow (AW-SSF), the parameters of the combined AD-AW system that treat a wastewater flow of 300 m3∙d–1 were calculated. The UASB acidogenic system was adjusted to a hydraulic retention time (HRT) of 10 h and organic loading rate (OLR) of 13.84 kg COD m–3∙d–1; meanwhile, the methanogenic and cascade UASB reactors with OLRs of 10.0 and 3.0 kg COD m3∙d–1, and HRTs of 11 and 10 h, respectively, achieve a high COD removal efficiency (above 94%), and an overall biogas production rate of 1.53 m3 of biogas per m3 of reactor capacity per day. According to the results obtained with the theoretical design, anaerobic-wetland combined system achieves an overall efficiency greater than 98%. The wastewater treated by the pro-posed system will allow the reuse of 30% of the water used in the washing of fruits and vegetables.