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.
The aim of the work was to determine the technological reliability of the selected pollution indicators removal BOD5, CODCr and total suspension from the sewage treatment plant working with the bioreactor Pomiltek Mann type. Wastewater treatment plant which is a subject of this study is located in Lesser Poland, in Siepraw commune. The analysis was per-formed using the Weibull method for basic indicators of impurities, BOD5, CODCr and total suspended solids. Physico-chemical analyses of raw and treated wastewater, were carried out in the period from 2003 to 2014 (11 years). The research period included measured values of pollutions indicators in 38 samples of raw and treated sewage. For each of pollution indicators descriptive statistic, percentage reduction (��) and treatment plant reliability factors (RF) were calculated. Aver-age reduction for BOD5 and TSS was on level equal 94%, only for COD the average reduction was lower and was on level 89%. The reliability values determined by Weibull method, were: 75% (BOD5), 90% (CODCr) and 89.5% (TSS). The relia-bility results have been lower than the presented by literature source, which means that work of wastewater treatment plant in Siepraw was not satisfied in 11 years of research.
The aim of the work was to analyze the effi ciency and reliability of pollutants removal (total suspended solids – TSS, BOD5, COD) in a collective wastewater treatment plant with activated sludge and hydroponic lagoon during its long term operation. The tested object was designed to treat wastewater in flowing through the sewerage system and wastewater delivered by the septic truck. The projected capacity of the treatment plant was 1200 m3∙d-1. The technological system for wastewater treatment consisted of a mechanical part, a flowing biological reactor working according to the BARDENPHO process, a secondary settling tank and a hydroponic lagoon. The efficiency and reliability of pollutants removal in the analyzed treatment plant were assessed on the basis of the data concerning influent and effluent wastewater collected during the years 2011–2018. On the basis of the measurements results, there were determined characteristic values of the selected pollution indicators in wastewater and the average efficiency of pollutants removal. The technological reliability of the wastewater treatment plant was assessed for the basic pollution parameters (BOD5, COD, TSS) in accordance with the elements of the Weibull’s reliability theory, with regard to normative values of the indicators specified in the Regulation of the Minister of Environment. The analysis was carried out using the Statistica 13.1 software. It was proved that in the wastewater treatment plant with an activated sludge and hydroponic lagoon the level of organic pollutants removal expressed by BOD5 was on average 99.5%, COD – 98.1% and TSS – 99.4%. The technological reliability of the system was 100% in terms of the removal of pollutants from the basic group, which means that during the long term operation (8 years) it provided failure-free operation and guaranteed the fulfillment of the requirements that can be found in the Polish law regulations concerning the analyzed pollutants.
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.