M3 Of Wastewater Research Articles

A Case Study On Predicting The Environmental Impacts Of Untreated Effluent Generated From Tannery Industrial Estate In Dhaka, Bangladesh

Significant amounts of heavy metals in the directly discharged wastewater released from the newly built tannery industrial site in Dhaka, Bangladesh are reported. Despite their detrimental impacts on public health and natural ecosystem, no environmental impact study is yet conducted. Therefore, information on safe discharge rates are not available. In this study, the extent of pollution around the industrial site is investigated for four representative trace metals. Temporal and spatial distributions of chromium (Cr), lead (Pb), cadmium (Cd) and arsenic (As) have been predicted using a numerical model with the aim to estimate safe discharge of these metal contaminants. From multiple simulation runs it has been estimated that a discharge of0.026 m3 of wastewater per day can lead to high levels of Cr and Pb accumulation, exceeding the regulatory standard limits, in the study area. Whilst As and Cd concentrations remain below the advised limits in most cases at this rate. However, an order of magnitude reduction in the total discharge rate, i.e.,0.0026 m3 per day, results into the metal accumulation below the recommended guidelines in all cases. Elevated concentration of Pb is found to be limited to the top 0.5 m of the soil as compared to Cr, As and Cd, which exhibit larger spread along the depth of the soil. The relative dominance of the metal contamination follows the sequence: Pb>Cr>As>Cd as sorbed concentration in soil aggregates and Cr>Pb>As>Cd as aqueous concentration in soil porewater. Further investigations that are essential for a comprehensive environmental impact assessment have been highlighted.

Recovery of struvite from hydrothermally processed algal biomass cultivated in urban wastewaters

A mixotrophic algal wastewater treatment system capable of reducing biochemical oxygen demand (BOD), ammoniacal nitrogen (NH4+-N), and phosphate (PO43−-P) in primary effluent in a single step has been demonstrated previously. Downstream processing of the resulting algal biomass by hydrothermal liquefaction (HTL) to recover its energy-content as biocrude oil has also been demonstrated. The current study evaluated the feasibility of recovering struvite from the two byproducts of HTL– a solid residue, rich in PO43–P; and an aqueous phase, rich in NH4+–N, for use as fertilizer. Results of this feasibility study and a preliminary mass balance model show that the proposed pathway can potentially yield ~2.5 kg struvite per 100 m3 of wastewater treated, recovering nearly 73% of PO43–P and 6% of NH4+–N in the primary effluent. Chemical and microscopic analysis of the wastewater-derived struvite revealed its composition to be close to that of pure struvite, with more than 12% P-content by weight. Scanning electron microscopy images depicted uniformly distributed sizes of irregular crystals in the wastewater-derived struvite. Low calcium content of this struvite indicated minimum amorphous calcium phosphate (ACP) impurities. Trace metal analysis showed that heavy metal levels in the recovered struvite were below current guidelines. This study confirmed the feasibility of recovering high-quality struvite from wastewaters, warranting further process optimization and characterization of the recovered struvite.

Quantifying urban wastewater treatment sector's greenhouse gas emissions using a hybrid life cycle analysis method – An application on Shenzhen city in China

Substantial amounts of greenhouse gas (GHG) emissions generated at urban wastewater treatment plants (WWTP) are gaining increasing appreciation. Improving upon the commonly used Process-Based Life-Cycle Analysis (PLCA) and Environmentally-Extended Life-Cycle Analysis (EIO-LCA) models, we construct a Hybrid Life Cycle Analysis (HLCA) model and quantify both direct and indirect GHG emissions at the operational stage of WWTPs in Shenzhen, one of the fastest urbanizing cities in the world. Data are collected from 26 wastewater treatment plants in Shenzhen, out of all 32, covering 5 commonly used wastewater treatment technologies in China, i.e. Sequencing Batch Reactor, Oxidation Ditch, Biological Filter, AAO-MBR and AAO. The results show that WWTPs using AAO-MBR technology have the highest GHG emission intensity, averaging 0.79 tons per m3, primarily due to its large electricity intensity required. WWTPs using other technologies emit 0.27 to 0.39 tons of GHGs per m3 of wastewater treated. GHG emissions associated with electricity use occupy the largest share, ranging from 65 to 75%. Therefore, transforming the energy structure of the electric power sector to low-carbon sources can reduce WWTPs operational GHG emissions. In total, GHG emissions from Shenzhen's urban wastewater sector have increased from below 0.5 million tons in 2012 to over 0.6 million tons in 2017. Inter-model comparison shows that EIO-LCA substantially underestimates the urban wastewater sector's GHG emissions using the water sector's average parameters while PLCA also results in minor underestimations due the omission of indirect emissions in the production stage of chemicals and other material inputs.

Can wastewater feed cities? Determining the feasibility and environmental burdens of struvite recovery and reuse for urban regions

Phosphorus (P) resources are decreasing at an alarming rate due to global fertilizer use and insufficient nutrient recovery strategies. Currently, more circular approaches are promoted, such as recovering P from wastewater in the form of struvite. This is especially attractive for urban areas, where there is a growing trend of local crop production and large volumes of wastewater are treated in centralized wastewater treatment plants (WWTPs). This research aims to assess the technical and environmental feasibility of applying a struvite recovery and reuse strategy to meet the P requirements to fertilize the agricultural fields of an urban region. To do so, we analyze the potential P recovery and the environmental impacts of integrating three recovery technologies (REM-NUT®, Ostara® and AirPrex®) in the two biggest WWTPs of the Àrea Metropolitana de Barcelona. The results show that all technologies are able to recover between 5 and 30 times the amount of P required to fertilize the agricultural area of the region annually (36.5 t). As can be expected, including P recovery technologies result in additional impacts per m3 of wastewater due to increased electricity consumption and chemicals required for the struvite precipitation. However, struvite recovery results in less eutrophication potential, especially in the REM-NUT® case, with an average reduction of 5.4 times. On the other hand, Ostara®, that recovers P from the digestate, had the lowest impacts (9 kgCO2eq/kgP), even compared to the production of mineral fertilizer. When we apply our findings to the whole region, we can see that chemical use for struvite precipitation and energy consumption during the wastewater treatment process are the elements with the greatest impact. Thus, choosing the most appropriate technology in the most suitable WWTP is the most efficient strategy to diminish the environmental impacts of the system.

MATERIAL FLOW ANALYSIS (MFA) AND ENERGY BALANCE ANALYSIS (EBA) AS TECHNICAL TOOLS FOR WASTEWATER POLLUTION CONTROL IN TEXTILE AND DYEING INDUSTRY – A CASE STUDY

The textile and dyeing industry consumes a large amount of water and discharges to the environment many pollutants including dyestuffs, auxiliaries, others. In this study, a selected textile and dyeing company was representing modern factory in Vietnam. Using STAN software, the authors have quantified and analyzed the material flows of the production lines and of the main pollutants in wastewater. Comparing with “business as usual” scenario, a new scenario with treatment and reuse of wastewater has been introduced. The discharge volume of wastewater from company was about 3,608.96 m3/day (or 1,317,270.4 m3/year). Loadings of the main pollutants in wastewater as COD, TSS, T-P and T-N were 1419.95, 1571.36, 17.77 and 50.16 ton/year, respectively. One meter of produced fabric consumes 0.025 m3 of water. Energy consumption of the wastewater treatment station was analyzed by SANKEY software. The energy consumption rate was 1.695 kWh per m3 of wastewater. Reuse of wastewater could save 1,129.05 kWh per day of electricity and 1,804.48 m3 per day of fresh water to be taken from the river source. Ozonation was the most consuming energy process at the wastewater treatment station, accounting for 58.88% of total wastewater treatment energy consumption.

Estimation of industrial water demand and reclamation in Jordan: A cross-sectional analysis

The present study quantified the industrial water demand and reclamation and identified the scale of water-intensive industries in Jordan. Five industrial sectors including 395 industrial factories were surveyed by means of a structured questionnaire. The gathered data that were assessed included all industrial sectors, number of employees, the types and quantities of products, water demand, wastewater generation quantities, and management practices. Water demand and wastewater generation indicators (the water use and wastewater generation per product or per worker or per time) were determined for each of the responded groups of industrial sectors. The total industrial water demand and effluents generation in the five industrial sectors were pragmatically extrapolated and calculated. Moreover, the water reclamation and reuse potentialities were assessed from both environmental and economic perspectives. The results showed that the monthly industrial water demand per worker is 0.634 m3 for domestic use, while that for process use is varied between 0.07 to 21.38 m3/tons product. The results also determined the wastewater generation indicators, where the domestic use is generating between 0.515 to 0.628 m3 of wastewater per month per worker, while that for process use is between 0.04 to 12.45 m3/tons product. Moreover, the scenario of on-site treatment of 90% of the generated wastewater to be used as alternative water for 37.83% of total process water demanded by the grouped industries, showed viability where 9.7 million cubic meter of fresh water can be saved annually, and at least 25,953.60 tons CO2 equivalent emission can be reduced.

Reduction in Energy Requirement and CO2 Emission for Microalgae Oil Production Using Wastewater

A comparative evaluation of energy requirement and CO2 emission was performed for native polyculture microalgae oil production in a wastewater treatment plant (WWTP). The wastewater provided nutrients for algae growth. Datasets of microalgae oil production and their details were collected from the Minamisoma pilot plant. Environmental impact estimation from direct energy and material balance was analyzed using SimaPro® v8.0.4. in two scenarios: existing and algal scenarios. In the existing scenario, CO2 emission sources were from wastewater treatment, sludge treatment, and import of crude oil. In the algal scenario, CO2 emission with microalgae production was considered using wastewater treatment, CO2 absorption from growing algae, and hydrothermal liquefaction (HTL) for extraction, along with the exclusion of exhausted CO2 emission for growing algae and use of discharged heat for HTL. In these two scenarios, 1 m3 of wastewater was treated, and 2.17 MJ higher heating value (HHV) output was obtained. Consequently, 2.76 kg-CO2 eq/m3-wastewater in the existing scenario and 1.59 kg-CO2 eq/m3-wastewater in the algal scenario were calculated. In the HTL process, 21.5 MJ/m3-wastewater of the discharged heat energy was required in the algal scenario. Hence, the efficiency of the biocrude production system will surpass those of the WWTP and imported crude oil.

Wood-Based Panel Industry Wastewater Meets Microbial Fuel Cell Technology.

Although the wood-based panel industry is not considered to be a water-consuming sector, it generates ca. 600 M m3 of wastewater every year on a global scale. The wastewater is usually highly polluted and environmentally toxic even after dilution. Common wastewater treatment techniques require high-energy input or addition of various chemicals to the treated wastewater, which cause secondary pollution and production of toxic sludge. Microbial fuel cells (MFCs) have become an attractive technology, allowing for zero-energy treatment of various types of wastewater with simultaneous production of electric current. Recent investigations have shown that MFCs can also be utilized for sustainable treatment and energy production from the wastewater generated by the wood-based panel industry. This article contains a critical summary of the investigations in this field as well as a discussion of the research needed and perspectives for the future.

Integrated assessment of sulfate-based AOPs for pharmaceutical active compound removal from wastewater

Advanced oxidation processes (AOPs) have been proposed as tertiary treatments for municipal WWTP effluents. UV-activated peroxydisulfate (PDS) and peroxymonosulfate (PMS) are viable technological alternatives for treating secondary WWTP effluent containing PhACs. This article examines the feasibility of applying UV/PDS and UV/PMS technologies at pilot scale, assessing their energy and cost requirements. In addition, life cycle assessment (LCA) impacts associated with the treatment of 1 m³ of wastewater with an effective average pharmaceutical active compounds (PhACs) removal of 80% has also been evaluated. Photolysis (UV) treatment alone was not capable of degrading PhACs to a sufficient extent in WWTP secondary effluent. The addition of 0.4 mmol of PDS or PMS, applying 416 mJ/cm2 of UV fluence, resulted in average removals of 84% and 85% for UV/PDS and UV/PMS, respectively. The electrical energy (kWh) required to degrade the mix of PhACs by one order of magnitude in 1 m³ of contaminated water was calculated as 0.9 kWh/m³/order and 0.8 kWh/m³/order 4 for UV/PDS and UV/PMS, respectively. However, the overall cost, including operation, materials and maintenance, of applying UV/PDS and UV/PMS, based on an average PhAC removal of 80%, was 0.088 €/m³ and 0.280 €/m³, respectively. From the sustainability assessment, the factors with the greatest environmental footprint for the UV/PDS process were chemical production (PDS: 52.9%, PMS: 85%) and electricity consumption (UV/PDS: 33.4%, UV/PMS: 11.2). Finally, the normalized environmental impact analysis showed that UV/PDS was associated with an environmental footprint three times lower than UV/PMS. The overall assessment revealed that UV/PDS is preferable to UV/PMS to remove PhACs in secondary effluents of municipal WWTPs having a lower economic and environmental impact.

Microalgae‐based biodiesel production in open raceway ponds using coal thermal flue gas: A case of West Bengal, India

AbstractIndia is one of the most populous countries and is the third largest greenhouse gas–emitting nation. Energy security is a serious issue for India as it relies heavily on fossil fuel imports. Biodiesel production using microalgae as feedstock can address both of these issues. In this study, the technical feasibility of microalgae‐based biodiesel production is carried out for a coal thermal power plant (i.e., Budge Budge Thermal Station) in the state of West Bengal, India, using a generic methodology. An oleaginous microalgae species that is tolerant toward flue gas was identified (i.e., Nannochloropsis sp). A 75‐acre open raceway microalgae production plant was designed keeping the costs, energy demand, and CO2 emissions low. The open raceway pond can use 38 tons of CO2, produce 19 tons of algal biomass, and treat 9320 m3 of wastewater per acre annually.

СИНТЕЗ ГІДРАЗИНУ ЯК МЕТОД ОЧИЩЕННЯ СТОКІВ ВИРОБНИЦТВА КАРБАМІДУ

Today, the search of promising directions of production improvement is an urgent task. In the process of carbamide synthesis, up to 1.5 m3 of wastewater per ton of product is formed. Steam condensate formed during the concentration of a carbamide solution in vacuum evaporators is the main part of the effluent. For purification, the effluent is sent to a hydrolyzer for the hydrolysis of carbamide. Next, a desorption of ammonia and carbon dioxide occurs. Sewage containing bound nitrogen compounds for further treatment are sent to biological treatment facilities. The effectiveness of biological purification does not exceed 80 %. The aforementioned method of wastewater treatment requires high costs of electric and thermal energy. Hydrolysis and desorption of juice condensate are estimated as the most modern and most promising way of waste disposal. This method is implemented in all plants for the synthesis of carbamide. The article considers a new method for the utilization of nitrogen-containing condensates of carbanide production by using them as secondary raw materials for hydrazine synthesis. A study of the synthesis of hydrazine in an electromagnetic synthesis reactor has been carried out. The effect of the flow rate of the reaction mixture entering the electromagnetic N2H4 synthesis reactor on the prod-uct yield has been studied. The dependence of the degree of conversion of total nitrogen to N2H4 on the flow rate of the reaction mixture into a multimode electromagnetic hydrazine synthesis reactor is established. Experimentally obtained data are mathematically processed in order to establish the optimal flow regime. The results of calculating the mathematical model of the kinetics of chemical reactions initiated by electromagnetic heating are confirmed by solving the system of Arrhenius equations and thermal conductivity in an implicit scheme. It has been confirmed that cyclic heating of the reaction mixture is more effective. In the course of studies, it is found that the synthesis of hydrazine proceeds in the diffusion area. Despite the fact that the absence of pumps reduces the energy consumption of a hydrazine synthesis plant from secondary raw materials, it is difficult to control the production process when introduced into production. The phenomenon of spontaneous regulation of the rate of removal of the synthesis solution from the reaction zone is initiated by the effects of internal airlift by CO2 gas and implosion.

Comprehensive comparison of chemically enhanced primary treatment and high-rate activated sludge in novel wastewater treatment plant configurations

Novel wastewater treatment plants (WWTPs) are designed to be more energy efficient than conventional plants. One approach to becoming more energy efficient is the pre-concentration of organic carbon through chemically enhanced primary treatment (CEPT) or high-rate activated sludge (HRAS). This study compares these approaches in terms of energy demand, operational costs, organic micropollutants (OMP), and virus removal efficiency. A CEPT pilot-scale plant was operated at a hydraulic retention time (HRT) of 30 min, and a lab-scale HRAS reactor was operated at an HRT of 2 h and a solid retention time (SRT) of 1 d in continuous mode. A minimum dose of 150 mg/L ferric chloride (FeCl3) was required to achieve a threshold chemical oxygen demand (COD)-to-ammonium ratio below 2 g COD to 1 g of NH4+ –N (fulfilling the requirement for a partial nitritation-anammox reactor), reaching high phosphate (PO43−)-removal efficiency (>99%). A slightly lower COD recovery was attained in the HRAS reactor, due to the partial oxidation of the influent COD (15%). The lower PO43− removal efficiency achieved in the HRAS configuration (13%) was enhanced to a comparable value of that achieved in CEPT by the addition of 30 mg/L FeCl3 at the clarifier. The CEPT configuration was less energy-intensive (0.07 vs 0.13 kWh/m3 of wastewater) but had significantly higher operational costs than the HRAS-based configuration (6.0 vs 3.8 c€/m3 of wastewater). For OMPs with kbiol > 10 L/gVSS·d, considerably higher removal efficiencies were achieved in HRAS (80–90%) than in CEPT (4–55%). For the remaining OMPs, the biotransformation efficiencies were generally higher in HRAS than in CEPT but were below 55% in both configurations. Finally, CEPT was less efficient than HRAS for virus removal. HRAS followed by FeCl3 post-treatment appeared to be a more effective alternative than CEPT for COD pre-concentration in novel WWTPs.

The performance of a pilot-scale anaerobic hybrid bioreactor on palm oil mill effluent treatment

Contemporarily, Indonesia and Malaysia are the largest contributors of crude palm oil (CPO) in the world by up to 40%, and 37.3%, respectively. Furthermore, its production value this year reached 19.7 million tons, where each generates 2.5 m3 of wastewater. Meanwhile, of all the provinces in Indonesia specifically, Riau is the largest supplier for exports by up to 38%, generated from 225 palm oil mills, where a total of 6.3 million tons resulting in the generation of about 15.75 million m3 of wastewater, with organic content between the range of 30,000-60,000 mg COD/l. In addition, one of the uses of this wastewater includes anaerobic processes, with the double benefit of reducing COD concentrations, subsequently applying it as fertilizer, and also in the production of methane gas, as an alternative source of energy. The purpose of this study, therefore, is to observe the effect of bioreactor volume, scale-up on the performance of anaerobic hybrid bioreactors, in the treatment of mill effluents. The technology examined in this study was the anaerobic hybrid bioreactor with the dimensions of length 22 m, width 10 m, and depth 1.5 m, and a total volume of 330 m3, which is impermeable to oxygen, and a 250 m3 effective working volume. This was built and operated at a hydraulic retention time of 1 day, in the Palm Oil Mill of Riau, and the results showed the environmental conditions to range from a pH of 7.2 to 8.0, with temperatures from 320C to 350C, acetic acid of 774 mg/l to 1,180 mg/l, and alkalinity of 2,149 mg/l up to 2,400 mg/l. Furthermore, the performance of these reactors are shown by the highest COD removal efficiency of 77.8%, and a biogas test for the propensity of being applied as an alternative energy source obtained a methane gas concentration of 54%. Keywords: anaerobic, bioreactor, biogas, wastewater, performance, palm oil mill effluent

Profitable sludge management via novel combined ozone disperser pretreatment coupled with membrane bioreactor for treating confectionary wastewater

Abstract In this study, two lab scale membrane bioreactor (MBR) with working volume of 12 L were used to study the effect of sludge pretreatment over period of 120 d. Among the two MBRs one was used as a control (U-MBR) and another one was used as experimental (P-MBR). After attaining stable operation, 540 mL/d of mixed liquor was withdrawn and subjected to Ozone Disperser Pretreatment (ODP). ODP results with 22% of Chemical Oxygen Demand (COD) solubilisation and 19% of solids reduction. Upon recycling ODP sludge, 36% of sludge reduction was achieved in P-MBR, when compared to U-MBR. The yield observed of P-MBR (0.165 g SS/g COD) is lower than U-MBR (0.254 g SS/g COD). The effluent organic concentration of both MBRs is in the range of 6–12 mg/L COD. Incorporation of ODP in P-MBR, reduces the cost to manage sludge for treating 1 m3 of wastewater from −0.0334 to −0.0276 USD.

Artificial neural network and cost estimation for Cr(VI) removal using polycationic composite adsorbent

AbstractA cationic adsorbent, namely polyamine/folic acid composite (PFC) was used to remove Cr(VI) from aqueous solutions. The optimum pH was 2.0, achieving Cr(VI) removal of 99.4% at an initial concentration 200 mg/L, PFC dosage 0.5 g/L and temperature 298 K within 90 min. Under the acidic condition, electrostatic attractions between anionic species of chromium ( and ) and cations on PFC (NR4+ and H+) enhanced Cr(VI) uptake. Additional removal mechanisms including anion exchange with Cl− (because of the use of epichlorohydrin for PFC preparation), reduction of Cr(VI) to Cr(III) and physical interaction could be involved in the adsorption process. Artificial neural network containing a first layer with five inputs, a hidden layer with eight neurons and the last layer with one output was able to predict the Cr(VI) removal efficiency (R2 = 0.919). The total cost of scaling up the adsorption system was $3.53 per m3 of wastewater containing 200 mg‐Cr(VI)/L.

Suitability of chemical and electrocoagulation process on sugar industry wastewater treatment

Socio-economics development of any nation depends on Industrialization. With increase in number of industries needs, water is an essential requirement and added extra burden in terms of fresh water and wastewater. Among all the industries, sugar-processing industry is one of them. To fulfill the demand, appropriate technology will require otherwise with limited resources low quality of water can be used for operation. The aim of this research work is to treat the wastewater generated from sugarcane-processing industry using chemical coagulation and electrocoagulation. The aluminium salt suitability of both treatments was carried out for iron and metal electrode. A result shows 82% chemical oxygen demand and 84% color removal with iron electrode was attended at 156 A−2 current density, optimum pH 6 and 120 min of treatment time. Finally, settling, filtrations, X-ray diffraction and scanning electron micrograph study also conform that iron electrode is more suitable to treat sugar industry wastewater. To treat 1 m3 of wastewater, 2.0 USD will be required including all expenses.

Use of biogas from tofu industry for domestic use at Probolinggo City - Indonesia

Tofu industries produce by product of whey which is still rich in organic content. Tofu industry of using soy bean of 1400 – 1600 kg/day produces 25 m3 of wastewater per day of 6321 mg COD/liter. This high content of COD and volume of wastewater instead of potential pollution could be transformed into biogas and used by local communities for domestic purposes like alternative energy for cooking. This study is aimed to assess the possibility of using wastewater from tofu industry by local communities for cooking. Asri Tofu Industry with such typical production of wastewater was assessed to treat its wastewater while the by-product of biogas would be used by local communities for cooking. About 38 m3 biogas per day could be produced per day and can be used by at least 117 houses in the nearby factories not far from 300 m from the factory. The use of biogas would reduce local community expenses to buy LPG and woods for cooking.

Investigation of energy efficiency in Gebze Wastewater Treatment Plant

An intensive amount of energy is used during the operation of wastewater treatment plants, depending on the processes and equipment employed. The equipment which exhibits a large scale of diversity varies widely in their energy requirements as well. Energy costs constitute the most important part of the budget in the operation of a treatment plant. The issue of energy conservation has become a crucial topic for wastewater treatment plants as the energy costs are on a rising trend in Turkey. This study is conducted to investigate the energy efficiency of Gebze Wastewater Treatment Plant located in Gebze district of Kocaeli by assessing the influent and effluent design and operation parameters of the plant and to determine unit energy consumption values required for treating a unit amount of wastewater. In the plant, removal of many contaminants like chemical oxygen demand, biological oxygen demand, suspended solids, total nitrogen and total phosphorus has been aimed. Approximate removal efficiency of chemical oxygen demand, biological oxygen demand and suspended solids is determined to be 93%, 98% and 94%, respectively. Total amount of treated wastewater was 2,020,723 m3/month on average, and total amount of electricity consumption of the plant is 819,754 kWh/month on average. The consumption of electricity used for treating 1 m3 of wastewater varies between 0.38 and 0.43 kWh. Although the amount of total energy use increases depending on the amount of pollutants in the incoming water and treated pollutants, unit energy costs decrease as expected.

Effluent Water Reuse Possibilities in Northern Cyprus

Northern Cyprus (NC) is suffering from limited water resources and reiterated drought condition experiences due to global warming effects. Previous studies revealed that the water management policy in the country is not sustainable from the perspective of demand and balance. Apparently, the reuse of recycled water will be an alternative resource and can be utilized for some specific purposes to reduce water extraction from the ground. It is expected that treated wastewater will reach 20 million cubic meters (MCM) per year after the completion of the new sewage system for Lefkosa. Today, 20,000 m3 of wastewater is treated at the Lefkosa Central Treatment Plant up to the secondary treatment level, in which the degree of treatment varies from 60% to 95% owing to the weather conditions in the country during the year. Effluent water reuse in NC was not accepted due to cultural belief. However, water scarcity was experienced in the country during the last decade, forcing the farmers to benefit from the recycled water. There is no regulatory framework available in the country for effluent water reuse. However, preparation studies are almost finalized after discussions among government and European Union (EU) agencies. Cyprus, as an EU country, has an obligation to treat the wastewater up to the secondary level before releasing it in an environmentally friendly nature, following the Directive 91/271/EEC. This paper analyzes the effluent water reuse possibilities as a component of integrated water resource management in Northern Cyprus considering laboratory experiment results. It appears that applying tertiary treatment in Northern Cyprus will allow 20 MCM of water contribution to the water budget and it will help protect the vulnerable environment. Also, since the cost of tertiary treatment will be 0.2 United States dollars (USD)/m3, it would be reasonable to prefer this process to the desalination of water, which costs of 1 USD/m3.

Resource recovery from sulphate-rich sewage through an innovative anaerobic-based water resource recovery facility (WRRF).

This research work proposes an innovative water resource recovery facility (WRRF) for the recovery of energy, nutrients and reclaimed water from sewage, which represents a promising approach towards enhanced circular economy scenarios. To this aim, anaerobic technology, microalgae cultivation, and membrane technology were combined in a dedicated platform. The proposed platform produces a high-quality solid- and coliform-free effluent that can be directly discharged to receiving water bodies identified as sensitive areas. Specifically, the content of organic matter, nitrogen and phosphorus in the effluent was 45 mg COD·L-1, 14.9 mg N·L-1 and 0.5 mg P·L-1, respectively. Harvested solar energy and carbon dioxide biofixation in the form of microalgae biomass allowed remarkable methane yields (399 STP L CH4·kg-1 CODinf) to be achieved, equivalent to theoretical electricity productions of around 0.52 kWh per m3 of wastewater entering the WRRF. Furthermore, 26.6% of total nitrogen influent load was recovered as ammonium sulphate, while nitrogen and phosphorus were recovered in the biosolids produced (650 ± 77 mg N·L-1 and 121.0 ± 7.2 mg P·L-1).