Wastewater Treatment Station Research Articles

Evaluation of the Efficiency of Hospital Wastewater Treatment Systems and Stations in the Atlantic and Littoral Departments of Benin

Evaluation of the Efficiency of Hospital Wastewater Treatment Systems and Stations in the Atlantic and Littoral Departments of Benin

Toxic potential evaluation of liquid effluents discharged into nature by the university hospital centers (UHC) and mixed wastewater treatment station (WWTS) at Ouagadougou-Burkina Faso.

In Burkina Faso, several investigations have raised suspicions that hospital liquid effluents are the source of contaminants in porbeagle-culture products and surface water in urban and peri-urban areas. This study aimed to evaluate the hygienic quality of hospital liquid effluents discharged into nature by the UHC Bogodogo (UHC-BOG), Yalgado Ouédraogo (UHC-YO), and the WWTS of Kossodo (WWTS-KOS). Thus, 15 samples of liquid effluents (five per site) discharged into nature were collected. Within the physicochemical parameters, the pH, chemical oxygen demand (COD), biochemical oxygen demand (BOD5), suspended solids (TSS), conductivity, copper, iron, hafnium, silver, mercury, lead, and cadmium of these samples were determined using standard methods. The mean values of pH were 8.84 ± 0.42,8.06 ± 0.54, and 8.55 ± 0.53 for WWTS-KOS, UHC-BOG, and UHC-YO, respectively. Conductivity values were 1956.80 ± 81.30, 812.80 ± 45.22, and 956.00 ± 39.96 µS/cm, respectively. TSS were 338.20 ± 38.80, 45.00 ± 5.79, and 187.80 ± 27.58mg/L, respectively. COD were 274.80 ± 20.46, 35.00 ± 5.52, and 139.80 ± 25.53mg/L, respectively. BOD5 were 186.40 ± 68.68, 26.20 ± 4.82, and 81.80 ± 15.63mg/L, respectively. Mercury values were 1.93 ± 0.38, 4.04 ± 0.38, and 14.37 ± 1.65µg/L, respectively. Lead values were 434.70 ± 202.42, 310.50 ± 4.09, and 367.43 ± 94.01µg/L, respectively. Cadmium values were 79.59 ± 19.48, 109.94 ± 8.43, and 80.26 ± 7.85µg/L, respectively. Copper values were 27.66 ± 3.33, 30.84 ± 1.65, and 28.32 ± 2.36mg/L, respectively. Iron was detected only on the STEP-KOS with an average of 71.01 ± 37.83mg/L. Hafnium values were 50.27 ± 4.49 and 51.58 ± 4.61mg/L for WWTS-KOS and UHC-BOG, respectively. Silver values were 34.26 ± 3.06 for WWTS-KOS. On the three sites, the differences found were significant (p < 0.05). Liquid hospital effluents from Ouagadougou discharged into nature on the whole do not compile with the Burkinabè normative values for the discharge of wastewater into the environment.

Detailed investigation of bio-foam characteristics of piggery wastewater reveals long chain fatty acids-dominated foaming mechanisms

Biological foam has seriously troubled the wastewater treatment process and brings significant challenges to effluent quality, process efficiency, and operation safety. This study systematically analyzed the characteristics of biological foam from three typical piggery wastewater treatment stations, identified the key substances causing biological foam, and revealed potential foaming mechanisms. Foaming characteristics evaluation indicated that, for piggery wastewater, the low surface tension (58.9– 69.7 mN·m−1) was the crucial factor leading to strong foaming capacity (r = −0.761), and high viscosity (0.24– 0.7 Pa·s) and zeta potential (−10.4 ∼ −15.3 mV) increased the foam stability (r = 0.857, −0.767, respectively). Multidimensional correlation analysis revealed that the long-chain fatty acids (LCFAs) in the influent of piggery wastewater were the key leading to the foaming issue, and their influences had two paths: the decrease of surface tension caused by LCFAs could directly induce a stronger foaming capacity (physicochemical path); moreover, LCFAs favored the enrichment of non-filamentous foam-related microbes (abundance >3.3 %) like Hydrogenophaga and Pseudomonas spp. to secrete more extracellular polymeric substances, increasing the viscosity and zeta potential to maintain the foam stability (biological paths). Based on the revealed foaming mechanism dominated by LCFAS, this study provided novel insight and valuable guidance for efficient and safe treatment of piggery wastewater.

Chemical characteristics and valuation of sewage sludge from four different wastewater treatment plants.

Sewage sludge contains plant nutrients and organic matter in its composition, making it a potential partial substitute for mineral fertilizers if it meets environmental, agronomic, and sanitary standards. The objective was to evaluate the content of nutrients and heavy metals in the sludge generated in four wastewater treatment stations (WWTPs) in Rio de Janeiro state and assess its potential value and usefulness. The samples of 19 batches from the WTTPs Alegria, Barra da Tijuca, Ilha do Governador, and Sarapuí were analyzed. The WWTPs differ in methods and processes used for treating sewage and sludge. The total contents of C, N, P, K, Ca, Mg, Fe, Al, Na, Co, Mn, As, Ba, Cd, Cr, Cu, Ni, Se, Pb, and Zn were evaluated, as well as the ratio C/N, pH, organic matter content, and electrical conductivity. The grouping of sludge samples was assessed using principal components (PCA) and cluster analysis. The economic valuation of sludge was conducted utilizing the substitute goods method, which compared the sludge's N-P-K contents with the prices of consolidated nutrient sources. All the evaluated sludge batches exhibited concentrations of heavy metals below the limits allowed by Brazilian law, along with high levels of nutrients and organic matter. Considering the chemical characteristics, all evaluated materials showed potential for agricultural use, but it is crucial to evaluate the microbiological characteristics of sludge batches before agriculture application. PCA and cluster analysis demonstrated that sludge samples from the same WWTP clustered close to each other, demonstrating higher similarity among themselves than with samples from other WWTPs. The sludge had an average added value of U$ 88.46 per megagram, considering the total contents of N, P, and K in its composition. Land application of sewage sludge can reduce the need to purchase mineral fertilizers, thereby supporting the feasibility of reusing this material in the agricultural sector.

Microalgae Recovery via Alkaline Flocculation in a Stabilization Pond

Purpose: This research study aimed to investigate alkaline flocculation for the recovery of biomass found in wastewater, with the presence of microalgae collected from the maturation pond of a Wastewater Treatment Station in Brazil. Methods: Alkaline flocculation assays were conducted up to 24 hours after samples were collected due to the nature of alkaline flocculation, which may occur spontaneously if samples are stored for too long. Flocculation was obtained using the three proposed bases: sodium hydroxide, calcium hydroxide and sodium carbonate. Results and conclusion: The efficiency tended to increase with increased pH. Sodium hydroxide as the base produced better results for pH values 11 and 12. Research implications: Possibility of dual use of microalgae, in bioremediation and, in doing so, in the production of biomass that can later be converted into biofuels. Originality/value: The search for sustainable technologies and the possibilities of use presented by microalgae is clear about the need to develop cultivation and harvesting methods that are economically viable.

Long-term monitoring of COVID-19 prevalence in raw and treated wastewater in Salvador, the largest capital of the Brazilian Northeast

Wastewater-based epidemiology (WBE) becomes an interesting epidemiological approach to monitoring the prevalence of SARS-CoV-2 broadly and non-invasively. Herein, we employ for the first time WBE, associated or not with the PEG 8000 precipitation method, for the detection of SARS-CoV-2 in samples of raw or treated wastewater from 22 municipal wastewater treatment stations (WWTPs) located in Salvador, the fourth most populous city in Brazil. Our results demonstrate the success of the application of WBE for detecting SARS-CoV-2 in both types of evaluated samples, regardless of the usage of PEG 8000 concentration procedure. Further, an increase in SARS-CoV-2 positivity rate was observed in samples collected in months that presented the highest number of confirmed COVID-19 cases (May/2021, June/2021 and January/2022). While PEG 8000 concentration step was found to significantly increase the positivity rate in treated wastewater samples (p < 0.005), a strong positive correlation (r: 0.84; p < 0.002) between non-concentrated raw wastewater samples with the number of new cases of COVID-19 (April/2021–February/2022) was observed. In general, the present results reinforce the efficiency of WBE approach to monitoring the presence of SARS-CoV-2 in either low- or high-capacity WWTPs. The successful usage of WBE even in raw wastewater samples makes it an interesting low-cost tool for epidemiological surveillance.

Assessment of Chemical Health Risks, Fire - Explosion Risks and Environmental Impact at Cluj Wastewater Treatment Station within Someș S.A. Water Company

Abstract Noticing the increase in attention given by legislation and national practice to the assessment of occupational health and safety risks of a chemical nature, the article summarizes and explains the results of the research carried out from this perspective in a waste water treatment/purification station. By resorting to a well-established method, especially on the European level, the risks for the safety and health of workers (from the perspective of inhalation and skin risks), fire-explosion risks and environmental risks were evaluated. Based on the results obtained, a preliminary, but extremely necessary and useful, diagnosis of the magnitude of these specific risks was made and - on this basis - prevention/protection measures were proposed which, once implemented, can lead to the minimization of the risk levels associated with the identified hazards specific to the three analysed vectors. Beyond the concrete results of an applied nature, the growth of which the synthesis is systematized can serve as a good practice guide for numerous practitioners in the field of safety and health at work in Romania, in order to increase the efficiency of chemical risk assessments and - implicitly - the effectiveness of mitigation measures for this risk so widespread in industrial activities, processes and operations.

New approach to monitoring a wastewater irrigation system controlled by the artificial neural network (ANN)

In this paper, a cost-effective and scalable wireless sensor network (WSN) system has been developed, targeting monitoring and observation applications. The system specifically emphasises wastewater control and management in the context of irrigation practises. An artificial neural network (ANN) technique, incorporating the Well Node approach, has been employed to process a one-year dataset collected from sensor nodes in an actual wastewater treatment station in Morocco. Thus, the acquired data include a range of parameters, such as electrical conductivity (EC), total dissolved solids (TDS), chlorine levels (Cl), nitrogen content (N), hydrogen carbonate concentrations (HCO3), and pH values. The proposed hybrid system incorporates the Kohonen self-regulating characteristic map for data validation and reconstruction, along with multilayer perceptrons for sample prediction. The selected ANN demonstrates impressive performance, with recognition rates exceeding 95% and an F1 score of approximately 96.81% in terms of wastewater reusability. In particular, the system exhibits robustness in handling uncertainties, deviations, and low information content in input data, allowing for informed decisions on usage or reprocessing through its self-learning capabilities. The study highlights the adaptability of the WSN system to different farming requirements and geographical areas, contributing to improved resource management, enhanced water utilization efficiency, and protection of plants, soil, and the environment. The research findings advance the understanding of ANN architecture and its unique modifications for effective wastewater control. The results also emphasise the effectiveness of the system during the adaptation and implementation phases, offering valuable insights for algorithmic improvements.

Evaluation of the Efficiency of the Wastewater Treatment Plant in the Women’s and Children’s Hospital in Ramadi, Anbar, Iraq

The current study was conducted to evaluate the efficiency of the wastewater treatment station in the Women’s and Children’s Hospital in the city of Ramadi. Samples were collected from the treatment plant (water entering the station and treated water) during the two study seasons (summer and winter). As some physical, chemical and biological characteristics of the water entering the station and the treated water were studied to find out the efficiency of this station. It included the physical properties (temperature and conductivity), while the chemical properties included (pH, chloride, total hardness, nitrates, and COD, Oils, greases and dissolved oxygen). Biological characteristics include the biological requirement for oxygen. As it was noted that the efficiency of the station in getting rid of the conductivity is 18.38the chloride is 6.79%, the total hardness is 55.58%, the nitrates are 26.3%, and the COD is 30.6%, while the efficiency of the station for the disposal of oils and greases was 40.5% and BOD 49.23%,. The results of the study showed that the use of the water coming out of the station for irrigation and drinking purposes is not valid because some of the determinants exceeded the permissible limit.

Molecular probing of dissolved organic matter and its transformation in a woolen textile wastewater treatment station

Woolen textile industry produces enormous wastewater (WTIW) with high pollution loads, and needs to be treated by wastewater treatment stations (WWTS) before centralized treatment. However, WTIW effluent still contains many biorefractory and toxic substances; thus, comprehensive understandings of dissolved organic matter (DOM) of WTIW and its transformation are essential. In this study, total quantity indices, size exclusion chromatography, spectral methods, and Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) were used for comprehensively characterizing DOM and its transformation during full-scale treatments, including influent, regulation pool (RP), flotation pool (FP), up-flow anaerobic sludge bed (UA), anaerobic/oxic (AO) and effluent. DOM in influent featured a large molecular weight (5–17 kDa), toxicity (0.201 HgCl2 mg/L), and a protein content of 338 mg C/L. FP largely removed 5–17 kDa DOM with the formation of 0.45–5 kDa DOM. UA and AO removed 698 and 2042 chemicals, respectively, which were primarily saturated components (H/C > 1.5); however, both UA and AO contributed to the formation of 741 and 1378 stable chemicals, respectively. Good correlations were found among water quality indices and spectral/molecular indices. Our study reveals the molecular composition and transformation of WTIW DOM during treatments and encourages the optimization of the employed processes in WWTS.

Naegleria australiensis isolated from a wastewater treatment station in Santiago Island, Cape Verde.

Despite the Naegleria genus being isolated from different natural environments such as water, soil, and air, not all Naegleria species are capable of causing infections in humans, and they are capable of completing their life cycle in environmental niches. However, the presence of this genus may suggest the existence of one of the highly pathogenic free-living amoeba (FLA) species: Naegleria fowleri or the brain-eating amoeba. This facultative parasitic protozoon represents a risk to public health, mainly related to domestic and agricultural waters. In this research, our main objective was to determine the existence of pathogenic protozoa in the Santa Cruz wastewater treatment plant, Santiago Island. Using 5 L of water we confirmed the presence of potentially pathogenic Naegleria australiensis, being the first report on Naegleria species in Cape Verde. This fact demonstrates the low efficiency in the treatment of wastewater and, consequently, a potential threat to public health. Nevertheless, more studies will be needed for the prevention and control of possible infections in this Macaronesian country.

Removal of residual benzohydroxamic acid-lead complex from mineral processing wastewater by metal ion combined with gangue minerals

Benzohydroxamic acid-lead (BHA-Pb) complex reagent is a commonly used collector for the flotation of oxidized ores such as tungsten ore, cassiterite, and ilmenite, but the BHA-Pb complex remaining in the mineral processing wastewater (MPW) after flotation is economically and efficiently difficult to remove. At present, the treatment technology usually starts from the treatment of MPW at a wastewater treatment station. However, the treatment cost is inevitably high due to the huge amount of MPW. In this study, a new process of removing residual BHA-Pb complex reagent from MPW in one-step using metal ions combined with gangue minerals in tailings pulp was proposed. It started from tailings pulp treatment and taking tailings reservoir as the main reaction site. The basic issues related to the new process were mainly studied. The concentration of BHA was characterized using chemical oxygen demand (COD). The results show that when Ca2+, Fe3+, or Al3+ was added to the BHA-Pb solution, only Fe3+ could effectively remove the COD of the BHA-Pb solution, while Ca2+ and Al3+ could not. This is because the BHA-Pb complex can be preferentially transformed into the BHA-Fe complex, and the COD of the BHA-Fe complex solution is most easily removed. However, BHA-Fe complex systems have dark colors and are difficult to settle. When gangue minerals are added to the BHA-Fe complex system, gangue minerals can play the role of coarse particles carrying fine particles settling, which is helpful to the sedimentation of the BHA-Fe complex system. The transformation mechanism between BHA-Pb and BHA-Fe complexes was explained by the conditional stability constants and Gibbs free energy changes analysis. In addition, the sedimentation mechanism of the BHA-Fe complex system was analyzed by zeta potential and scanning electron microscope-energy dispersive spectrometer. This study provides a new idea for removing residual organic flotation reagents from MPW starting from tailings pulp treatment.

Elaboration and Characterization of a Biochar from Wastewater Sludge and Olive Mill Wastewater

The objective of this study is to valorize two waste products which, until now, caused major problems concerning their management and impacts on the environment and health. This study concerns the sludge of the wastewater treatment station of the city of Fez-Morocco and the olive mill wastewater, which are produced, respectively, in quantities of around 51,100 t/year and 514,350 m3/year, by pyrolysis for the production of biochar. The obtained biochar was characterized by physicochemical and spectroscopic analyses. The results show that the biochar is close to neutrality and is characterized by an important organic and mineral load; further, it is endowed with a porous surface, which could facilitate the adsorption of different polluting substances, composed mainly by micropores. It is mainly composed of alcohol, phenol, carboxyl and phenyl groups, as well as other mineral elements including silica and calcite. The composition, structure and morphology of the biochar thus prepared recommend its use in various fields, such as the treatment of pollutants, organic amendment, the reinforcement of polymers and as a secondary building material.

Metal ions synergize with gangue minerals to remove residual sodium oleate from mineral processing wastewater

The removal of residual organic flotation reagents from mineral processing wastewater (MPW) can be divided into two steps: the tailings pulp settles in the tailings reservoir, and the effluent from the reservoir is treated in a wastewater treatment station. To simplify the wastewater treatment process, this work explored the fundamental problems of removing residual sodium oleate (NaOl) from tailings wastewater by one step starting from tailings pulp treatment. The removal behavior and mechanism of NaOl from wastewater by metal ions combined with gangue minerals in the tailings pulp were studied. The concentration of NaOl was determined using chemical oxygen demand (COD). Results showed that the newly prepared 100 mg/L NaOl solution formed NaOl colloid after a period of time, and Fe3+ and Al3+ were more conducive to the COD removal of NaOl colloid than Ca2+. Moreover, metal ions and gangue minerals played a synergistic role in enhancing the COD removal of NaOl colloid. Mechanism analysis showed that the unit charge solubility of FeOl3 or AlOl3 was much lower than that of CaOl2, so Fe3+ or Al3+ was more likely to precipitate with NaOl than Ca2+. The addition of Fe3+ or Al3+ to NaOl colloid reduced the absolute value of the zeta potential of the suspended solids under suitable pH conditions, leading to colloid condensation. When metal ions and gangue minerals coexisted, gangue minerals adsorbed part of NaOl and played the role of coarse particles carrying fine particles to settle. This finding can be used to explain the synergistic effect of metal ions and gangue minerals. The study provides a new idea for the treatment of MPW and has great application prospect.

Oral Administration of a Phage Cocktail to Reduce Salmonella Colonization in Broiler Gastrointestinal Tract-A Pilot Study.

Salmonella contamination in poultry meat products can lead to serious foodborne illness and economic loss from product recalls. It is crucial to control Salmonella contamination in poultry from farm to fork. Bacteriophages (phages) are viruses of bacteria that offer several advantages, especially their specificity to target bacteria. In our study, three Salmonella phages (vB_SenS_KP001, vB_SenS_KP005, and vB_SenS_WP110) recovered from a broiler farm and wastewater treatment stations showed high lysis ability ranging from 85.7 to 96.4% on over 56 serovars of Salmonella derived from several sources, including livestock and a broiler farm environment. A three-phage cocktail reduced S. Enteritidis and S. Typhimurium, in vitro by 3.9 ± 0.0 and 3.9 ± 0.2 log units at a multiplicity of infection (MOI) of 103 and 3.8 ± 0.4 and 4.1 ± 0.2 log units at MOI of 104 after 6 h post-phage treatment. A developed phage cocktail did not cause phage resistance in Salmonella during phage treatments for three passages. Phages could survive under simulated chicken gastrointestinal conditions in the presence of gastric acid for 2 h (100.0 ± 0.0% survivability), bile salt for 1 h (98.1 ± 1.0% survivability), and intestinal fluid for 4 h (100 ± 0.0% survivability). Each phage was in the phage cocktail at a concentration of up to 9.0 log PFU/mL. These did not cause any cytotoxicity to human fibroblast cells or Caco-2 cells as indicated by the percent of cell viability, which remained nearly 100% as compared with the control during 72 h of co-culture. The phage cocktail was given to broilers raised in commercial conditions at a 9 log PFU/dose for five doses, while naturally occurring Salmonella cells colonized in the gastrointestinal tract of broilers were significantly reduced as suggested by a considerably lower Salmonella prevalence from over 70 to 0% prevalence after four days of phage treatment. Our findings suggest that a phage cocktail is an effective biocontrol agent to reduce Salmonella present in the guts of broilers, which can be applied to improve food safety in broiler production.

Testing Groundwater Quality in Jouamaa Hakama Region (North of Morocco) Using Water Quality Indices (WQIs) and Fuzzy Logic Method: An Exploratory Study

Groundwater is one of the important determinants of human health in many regions of Morocco. Indeed, it is one of the government’s top concerns. However, slow and wrong decisions are hindering the advancement of the quality of groundwater in Morocco. The traditional monitoring methods are costly, time-consuming, and human-resource-intensive, especially in such a developing country. An exploratory study was conducted in the Jouamaa Hakama region in Morocco to test and compare groundwater quality using in situ measurements, water quality indices (WQIs), and a fuzzy logic (FL) method. The methodology followed in this study involves using and comparing four WQIs and FL based on in situ measurements at nine different wells along the Ouljat Echatt River downstream of the Chrafate wastewater treatment station. Twelve physical–chemical and bacteriological parameters: potential of hydrogen (pH), temperature (T°), turbidity (TURB), chemical oxygen demand (COD), biochemical oxygen demand in five days (BOD5), suspended matter (SM), phosphate (PO43−), nitrite (NO2−), nitrate (NO3−), ammonium (NH4+), dissolved oxygen (DO), electrical conductivity (EC), and fecal coliforms (FC) were measured in 2016 and 2017. The results show that all wells are of poor quality according to FL and WQIs; the Weighted Geometric WQI and Oregon WQI indicate that the groundwater is below the acceptable standard for human consumption, while the Weighted Arithmetic WQI and Logarithmic WQI indicate that the majority of wells are of good quality. These tested indices represent an excellent tool to support decision making and can be highly helpful in monitoring groundwater quality in vulnerable areas such as the Jouamaa Hakama region in the north of Morocco.

Broad lytic spectrum of novel Salmonella phages on ciprofloxacin-resistant Salmonella contaminated in the broiler production chain.

Background and Aim:Ciprofloxacin (CIP) is recommended for salmonellosis treatment as the drug of choice; however, overuse of this drug can cause drug resistance issues and failure to treat diseases. Phage therapy is an alternative approach for combatting CIP-resistant infection. This study aimed to estimate the prevalence of CIP-resistant Salmonella isolated from the broiler production chain and evaluated the lytic ability of novel Salmonella phages isolated from water samples.Materials and Methods:Samples were obtained from the broiler production chain and used for Salmonella isolation. serovar and CIP resistance of each isolate were characterized through latex agglutination and agar disk diffusion test, respectively. Water samples from different sources were acquired for phage isolation. The lytic activity of novel-isolated phages was also examined.Results:In this study, 51 Salmonella isolates were recovered from the broiler production chain (two commercial farms, one free-range farm, two slaughterhouses, and three stalls from the wet market). Kentucky was the major serovar characterized (16), followed by Typhimurium (9), Agona (5), Corvalis (5), Schwarzengrund (5), Singapore (3), Weltevreden (3), Mbandaka (2), Give (2), and Albany (1). The serovars that exhibited CIP resistance were 14/16 isolates of serovar Kentucky (87.5%) and one isolate of serovar Give (50%), whereas eight other serovars were susceptible to this drug. Overall, the prevalence of CIP-resistant Salmonella recovered from the sources included in this study was 29.4%. This study identified 11 Salmonella phages isolated from wastewater samples derived from broiler farms, wastewater treatment stations, and natural reservoirs. Our phages showed the total percentage of lysis ability ranging from 33.3% to 93.3% against CIP-resistant isolates. However, only one bacterial isolate, namely 210SL, recovered from the food contact surface of a wet market stall and was resistant to all phages.Conclusion:Diverse serovars of Salmonella were recovered in the broiler production chain in this study, while the isolates presenting CIP-resistant Salmonella were as high as 29.4%. Overall, Salmonella phages showed high lysis ability against these CIP-resistant Salmonella isolates, suggesting the potential application of phage-based treatments or biocontrol in the broiler production chain.

Suggestions and regulations for designing, planning and constructing industrial parks, a case study of Vietnam

On the basis of experiences in designing, planning and constructing industrial zones in Vietnam, this paper aimed to give some suggestions and regulations for designing. The study used the qualititative method with synthesis and explanatory methods. Resources usage and environmental protection are more effective, while maximal economic and social benefits are simultaneously targeted. A concept of developing eco-industrial parks has established and evolved through time, and planning and constructing industrial zones based on current regulations in the nation. As a result, researches stated that we need to pay attention to network cloud service, big data service and investment management and meet some standards such as 100% of newly built industrial clusters have wastewater treatment stations that meet relevant national standards or technical regulations, etc. as well as certain principles such as 3R (Recycle, Reduce, Reuse). Operation services should include: cloud-based service operation providing basic cloud rental services, such as cloud hosting, cloud desktop, cloud disk, virtual data center, container services, collaborative development and Open API; SaaS Operation Service; APP Store; and space operation service to make full use of digital showrooms and free space resources, providing reservation and rental services, and demonstration services.

Overcoming Barriers to the Implementation of Cleaner Production in Small Enterprises in the Mechanics Industry: Exploring Economic Gains and Contributions for Sustainable Development Goals

The purpose of this study is to evaluate the economic and environmental gains that result from the implementation of cleaner production in a small enterprise (SE) from the metal and mechanics industry, allowing for overcoming barriers and contributing to sustainable development goals. The research work builds on a case study that involved several data sources, including semi structured interviewing and non-participant observation. Data analysis involved the calculation of mass balance, building solid and liquid waste that were minimized in the process. The results suggest that cleaner production led to economic gains, by allowing for reduction in losses and promoting a better use of raw materials. It also led to environmental improvements by means of the implementation of a wastewater treatment station that allowed for the reuse of water in the manufacturing process. It was concluded that the economic gain in the project played a determinant role for the SE to overcome the barriers for the implementation of CP and leading to the reduction of the environmental impact in the abiotic, biotic, water and air compartments, as estimated with the Mass Intensity Factor. The study offers a timely and relevant contribution for the literature in the field, while offering insights for o managerial practice, and the attainment of the Sustainable Development Goals defined by the United Nations Development Program.

Biogas manufacture from co-digestion of untreated primary sludge with raw chicken manure under anaerobic mesophilic environmental conditions

This work aimed to co-digest various wastes to assess the best combination of all mixing ratio, also at choosing the best ratio between untreated primary sludge (UPS) singly from two sources, (South valley University (SUPS) and Abu tesht wastewater station (AUPS) and raw chicken manure (RCM) and comparing the results in either case. The co-digestions of untreated primary sludge from Abu tesht wastewater treatment stations with different levels of raw chicken manure (0:100, 10:90, 30:70, 50:50, 90:10, and 100:0) to obtain the best mixtures. Also, co-digestion of untreated primary sludge from south valley university with different levels of raw chicken manure at the same ratios, to obtain the best mixtures. Batch digestion tests were applied in 2.5 L digester with a working volume of 2.0 L. The samples in triplicates were separately loaded into the digesters locally fabricated and kept for 20 days as a retention period and diluted with the same amount of water. Mesophilic under 35 °C was adopted for untreated primary sludge as well as mixtures with raw chicken manure based on total solids (TS) and volatile solid (VS) proportions. The average biogas yields from AUPS/RCM mixture obtained ranged from 8570 to 5600 ml, by the following descending order, 10: 90 > 90:10 and so on >100:0, and the average biogas yields from SUPS/RCM obtained ranged from 6330 to 5635 ml, in the order of 90: 10 > 10:90 and so on >100:0. The results showed highest biogas yield from AUPS/RCM and SUPS/RCM mixtures with mixing ratio of 10:90 and 90:10, respectively, however, the lowest biogas production detected in separate digestion of AUPS and SUPS. The results indicated that co-digestion between the sludge and raw chicken manure could increase total biogas production volume, enhance sludge treatment process, and produce eco-friendly sludge because of co-digestion process than separate processing of each feedstock.