Total Chloride Ion Research Articles

Influence of water scouring on chloride ion diffusion in rice husk ash recycled aggregates concrete

This study investigates the chloride ion diffusion behavior in concrete incorporating rice husk ash (RHA) and recycled aggregates (RA) under water scouring conditions. The research results indicate that both free and total chloride ion concentrations in recycled aggregate concrete (RAC) exhibit an initial increase, followed by a subsequent decrease, as the distance from the concrete surface increases. The incorporation of RHA reduces both free and total chloride ion concentrations while increasing bound chloride ion content. However, an excessive amount of RHA can weaken the resistance of RAC to chloride ion penetration. Water erosion deteriorates the internal microstructure of RAC, accelerating the transport of free and total chloride ions. However, it does not compromise the chloride ion binding mechanism conferred by RHA. The fine particulate of RHA provides additional nucleation sites for cement hydration, while the reservoir effect ensures a steady supply of free water to these sites. This synergistic interaction enhances the pozzolanic reaction between cement hydration products and RHA, resulting in reduced Ca(OH)₂ content and increased formation of C-S-H gel.

Effect of chloride binding and sulfate ion attack on the chloride diffusion in calcium sulfoaluminate-based material under seawater environment

The diffusion of chloride ions in reinforced concrete under the seawater environment will affect the physical or mechanical properties and durability. Sulfate ions also influence the diffusion of chloride ions by generating expansion products through physical and chemical reactions. Further research on the effects of chloride binding and sulfate ion attack on chloride ion diffusion will deepen the understanding of concrete failure mechanism. In this paper, a quaternary blend based on calcium sulfoaluminate (CSA) cement was prepared and laboratory immersion tests were conducted in artificial seawater with varying salt concentrations. Initially, chloride ion concentration measurements and XRD tests were conducted at different corrosion ages and salt concentrations. Subsequently, the chloride binding properties of CSA-based materials was quantified through the analysis of chloride ion concentration and the phases of hydration products. Meanwhile, the corrosive effect of sulfate ions on chloride ion diffusion was determined corresponds to the content of expansive hydration products. Furthermore, numerical simulations were employed to evaluate the impact of sulfate ion corrosion, chloride binding, and their combined effects on chloride ion diffusion, and the results were compared with free chloride ion concentration (Cf). The results indicate that the total chloride ion concentration (Ct) exhibits a linear relationship with increasing salt concentrations of seawater in CSA-based materials. Meanwhile, the bound chloride ion concentration (Cb) follows a logarithmic growth pattern. The chloride binding rate experiences a linear decline with the increase of chloride ion concentration in the artificial seawater. Additionally, the relationship between Cf and Cb or Ct can be described using different isothermal adsorption models for the CSA-based materials. Among these models, the Langmuir model is suitable for characterizing the relationship between Cf and Cb, while the Freundlich model is suitable for describing the relationship between Cf and Ct. Furthermore, it is noteworthy that sulfate ion attack and chloride binding exert nearly equivalent effects on the diffusion of chloride ions in CSA-based materials at short corrosion age and low chloride ion concentration. However, the corrosive impact of sulfate ions gradually evolves into the dominant factor in the progression of corrosion over time and the increase in seawater salt concentration.

Salt-tolerant plant growth-promoting Pseudomonas atacamensis KSS-6 in combination with organic manure enhances rice yield, improves nutrient content and soil properties under salinity stress.

In the current study salt tolerant-plant growth-promoting rhizobacteria (ST-PGPR) Pseudomonas atacamensis KSS-6, selected on the basis of prominent plant growth-promoting (PGP) and stress tolerance properties was tested as bioinoculant to improve yield of rice grown in saline soil. The ST-PGPRKSS-6 was capable of maintaining the PGP traits up to 200 mM NaCl, however, higher salt stress conditions affected these activities. The study was designed to determine the effect of developed talc-based bioformulation using KSS-6 along with organic manure (OM) on growth and yield of paddy under saline conditions. Bioformulation broadcasting was also done to examine the effect on soil properties. It was found that the combinatorial treatment showed positive impact on growth and yield of rice under saline conditions. Co-application of KSS-6 with OM showed maximum increment in growth, chlorophyll content, plant fresh weight, and dry weight as compared to untreated control plants. Furthermore, the combinatorial treatment improved the nutrient content (P, K, Zn, Fe, Mg, and Mn) by more than 35% and enhanced the biochemical parameters such as proline, flavonoids, carbohydrates, protein, dietary fiber, and antioxidant content of rice grains by more than 32%. Soil parameters including pH and electrical conductivity(EC), moisture content, total organic carbon, OM, sodium, and chloride ions were also improved upon treatment. There was significant lowering of EC from 7.43 to 4.3 dS/m when combination of OM and bacteria were applied. These findings suggest that the application of KSS-6 in the form of bioinoculant could be a promising strategy to mitigate negative impacts of salt stress and enhance the yield and nutritional properties of rice grown in degraded and saline soil.

Machine Learning Method to Explore the Correlation between Fly Ash Content and Chloride Resistance.

Chloride ion corrosion has been considered to be one of the main reasons for durability deterioration of reinforced concrete structures in marine or chlorine-containing deicing salt environments. This paper studies the relationship between the amount of fly ash and the durability of concrete, especially the resistance to chloride ion erosion. The heat trend map of total chloride ion factor correlation displayed that the ranking of factor correlations was as follows: sampling depth > cement dosage > fly ash dosage. In order to verify the effect of fly ash dosage on chloride ion resistance, three different machine learning algorithms (RF, GBR, DT) are employed to predict the total chloride content of fly ash proportioned concrete with varying admixture ratios, which are evaluated based on R2, MSE, RMSE, and MAE. The results predicted by the RF model show that the threshold of fly ash admixture in chlorinated salt environments is 30-40%. Replacing part of cement with fly ash in the mixture of concrete below this threshold of fly ash, it could change the phase structure and pore structure, which could improve the permeability of fly ash concrete and reduce the content of free chloride ions in the system. Machine learning modeling using sample data can accurately predict concrete properties, which effectively reduce engineering tests. The development of machine learning models is essential for the decarbonization and intelligence of engineering.

Chloride ion permeation and electrochemical impedance response of red mud-coal metakaolin geopolymer concrete

In geopolymer concrete, chloride ions largely contribute to the surface passivation of steel reinforcement and accelerate its corrosion. However, real-time nondestructive testing of chloride ion diffusion has not been widely conducted. Therefore, this study determined the distribution of chloride ions in red mud-coal metakaolin geopolymer concrete with different water-binding ratios under natural immersion conditions. The electrochemical properties of geopolymer concrete in a sodium chloride environment were examined by electrochemical impedance spectroscopy (EIS) and the relationship between these properties and the chloride ion diffusion coefficient was established. The experimental results showed that the contents of free chloride ions, total chloride ions, and bound chloride ions gradually decreased with increasing penetration depth; total chloride ions and free chloride ions increased at the same depth with increasing water-binder ratio; and bound chloride ions decreased with increasing ratio. In addition, the contents of free chloride ions, total chloride ions, and bound chloride ions gradually increased with the increase of the immersion age. The EIS results showed that there was a significant correlation between the diffusion coefficient and the electrochemical parameters. Therefore, EIS is suitable for detecting the diffusion of chloride ions in geopolymer concrete.

Effect of CaO/SiO2 and Al2O3/SiO2 on the chloride permeability of one-part alkali-activated nickel slag concrete

To study the effect of CaO/SiO2 and Al2O3/SiO2 ratios on the chloride permeability of one-part alkali-activated nickel slag (AANS) concrete, the chloride ion electromigration coefficient and the distribution of total chlorine concentration at different permeability depths of the one-part AANS concrete were investigated. The ratio of CaO/SiO2 and Al2O3/SiO2 of cement were designed in the range of 0.85–1.3 and 0.3–0.75, respectively. The reaction product and pore structure of paste were analyzed. The Results showed that the total chloride ion concentration in concrete first decreased and then increased with CaO/SiO2 and Al2O3/SiO2 ratios increasing. The chloride permeability of the concrete with CaO/SiO2 of 1.0 and Al2O3/SiO2 of 0.45 was the lowest, as the hydration degree of the concrete was the highest, which effectively optimized the pore structure. The chloride ion migration coefficient of concrete decreased with porosity, and an exponential relationship was observed between the chloride ion migration coefficient with porosity.

Time-depth dependent chloride diffusion coefficients of self-compacting concrete

Chloride attack severely impacts the performance of reinforced concrete. The total and free chloride ion concentrations (CICs) of self-compacting concrete (SCC) prepared with three supplementary cementitious materials (SCMs) - fly ash (FA), blast furnace slag (BS), and silica fume (SF) – were measured through the accelerated salt immersion tests. The apparent chloride diffusion coefficients (CDCs) at any exposure time and erosion depth were calculated using the Boltzmann-Matano method. The influence of the type and content of SCMs, the water-binder ratio (W/B), and the type of salt solution on CICs and CDCs were investigated. Both introducing SCMs and reducing W/B effectively reduced the CIC. The SCM that most effectively reduced CIC was SF, followed by BS and then FA. Free CICs were reduced to a greater degree than total CICs in FA and BS concrete, but the opposite was true for SF concrete. Presence of calcium chloride in salt solution increased total CICs while reducing free CICs. Apparent free CDC dropped over exposure time and initially increased with erosion depth but eventually stabilized. A model of apparent free CDC considering the time-depth dependence was created, which shows that time reduction factors of CDC is larger in SCM-containing SCC than in control SCC.

Effect of calcium leaching on the characteristics of chloride physical adsorption and chemical binding of cement-based materials

Chloride corrosion is an important reason for the degradation of bearing capacity of reinforced concrete structures. When chloride ions transport from external environment into concrete, a part of ions will be bound by the cement matrix through the behaviors of chemical binding and physical adsorption. In this paper, the cement paste samples (R0, R5 and R15) with different degrees of calcium leaching are prepared to investigate the chloride binding capacity, by performing the experiment of chloride isothermal adsorption and desorption. In the experiment, the R0, R5 and R15 are immersed into NaCl-CH composite solutions with different chloride concentrations (Cf-Cl). The change of total binding chloride ion (TBCI), physically adsorbed chloride ion (PACI) and chemically bound chloride ion (CBCI) concentrations in the samples with Cf-Cl is obtained. Then, the linear and nonlinear adsorption laws are adopt to fit the experimental data of chloride concentrations, and the most appropriate adsorption laws are determined separately for the behaviors of TBCI, PACI and CBCI. Finally, the equations for chloride binding capacity of R0, R5 and R15 are obtained, which can be used to analyze the capacity of TBCI, PACI and CBCI of cement-based materials subjected to calcium leaching.

The Effect of Mg2+on the Solidification of Chloride Ions in Portland Cement Paste

In order to investigate the mechanism of the effect of Mg2+ on the solidification of chloride ions in hardened Portland cement slurry, a NaCl-MgCl2 composite solution was used to soak and corrode the hardened Portland cement slurry. Under the condition of fixed total chloride ion concentration of 0.6mol/L, the effects of Mg2+ concentration (0.1mol/L, 0.2mol/L, 0.3mol/L) and soaking time in environmental solutions on Friedel salt production, leaching Ca2+ ion concentration, and leaching of hardened Portland cement were studied The influence law of pH value and other properties in erosive environments. The results showed that in the early stage of immersion erosion, Mg2+ had little effect on the rate of pH increase of the erosion solution; After the pH value of the solution stabilizes, the final pH value of the solution decreases with the increase of Mg2+ concentration; As the concentration of Mg2+ in the erosion solution increases, Mg2+ promotes the dissolution of hydration product Ca(OH)2 and the dissolution of Ca2+, while generating Mg(OH)2 precipitates, resulting in a decrease in solution alkalinity and an increase in the amount of chloride ions solidified; When the pH of the solution exceeds 12.1, a lower pH value will promote the formation of Friedel salts; When the pH of the solution is less than 12.1, higher concentrations of Mg2+ cause Friedel salt to decompose.

Satellite-Based Statistical Analysis of Hilla River Water Quality Parameters, Iraq

Since industrial and human activities have been developed, water quality intensely degrades in Hilla River, Iraq. Using remote sensing technology provides data for assessing and monitoring water quality in surface water bodies. Thus, in this study, Landsat 8 satellite images (2016 to 2021) were statistically tested for developing linear models capable of estimating water quality parameters in the river based on field data, including turbidity (turb), electric conductivity (EC), hydrogen ions (pH), total suspended solids (TSS), chloride ions (Cl), sulfate ions (SO4), Alkalinity (ALK), total hardness (TH), calcium (Ca), potassium (K), sodium (Na), magnesium (Mg), and total dissolved solids (TDS). The results showed that seven parameters have a significant relationship with the spectral bands ratio (p-value less than 0.05). Some of them (TDS, SO4, and ALK) are positively correlated with bands ratio (Band10/Band3, Band10/Band3 and Band10/Band4, and Band3/Band7), respectively. Others (Mg, Ca, TH and pH) are inversely correlated with (Band4/Band7, Band1/Band4, Band1/Band4, and Band1/Band2), respectively. However, K, Na, TDS, Cl, EC and turb have an insignificant correlation with any band ratio.

Effect of crack width and wet-dry cycles on the chloride penetration resistance of engineered cementitious composite (ECC)

• Influence of crack width and wet-dry cycles on the chloride ingress in cracked ECC was investigated. • Chloride penetration profile as well as the change of total and water-soluble chloride ion content was measured. • The “maximum phenomenon” is observed for both water-soluble and bound chloride ions profiles under wet-dry cycles. • The change of the mineral phases and porosity is related with the chloride binding behaviour. The resistance of cracked ECC against chloride ingress is mainly governed by the accumulated crack width of all the cracks rather than the maximum width of multiple cracks. However, most studies focus on the influence of a single fine crack (<100 μm), which is far smaller than the accumulated crack width. To this end, this study focuses on a relatively large crack width scale. Cracks with widths of 0.1, 0.2 and 0.3 mm were notched on an ECC specimen. Both NaCl solution immersion and wet-dry cycles conditions were applied. Chloride penetration profile as well as the change of total and water-soluble chloride ion content was measured. Relationship between the bound chloride and water-soluble chloride was studied. X-ray diffraction (XRD) and mercury intrusion porosimetry (MIP) tests were carried out to show the influence of crack width and wet-dry cycles on the changes of the mineral phases, porosity and pore size distribution in the vicinity of the crack.

Properties and durability of partially replaced cement-based composite mortars co-using powders of a nanosilica superplasticiser and finely ground plastic waste

This paper was about an experimental work on properties and durability of partially replaced cement-based composite mortars. Substitutions equal to 0, 2, 4 and 6% of finely ground polyethylene (PE) in association with a 3% nanosilica superplasticiser (SP) were used to cast the composite mortars. Fresh properties concerned setting as well as compressive strength versus porosity accessible to water whereas hardened durability properties were investigated by carbonation according to FT-IR, chloride corrosion of reinforcement, total chloride ion content, steel bars losses of mass and nitric acid attack. The superplasticiser and polyethylene powder inhibited the hydration of the cement while the compressive strength decreased with the rise of the polyethylene content but remained higher than the control mortar one for a (PE) content not exceeding 4%. Composite mortars were less porous and experienced a 2.08% average porosity. Under carbonation, composite mortars exhibited similar performance with the control mortar while corrosion and steel bar mass losses readings revealed the passive condition of the composite mortars and a total chloride content less than 0.4%. Composite mortars demonstrated better resistance to nitric acid attack with (PE) content increase. Correlation of the SEM images and X-ray evidence with the experimental records may be an indication of the feasibility of providing composite mortars with an optimal 2% (PE) for concrete constructions under severe environmental conditions.

The efficiency of some fungi species in wastewater treatment

Using microorganisms in eliminating or reducing the impacts of harmful remnants is very ancient manner. The current study was conducted to explore the potential of utilizing some fungi species that isolated from the main sewage treatment plant in Al-Muamirah area, Babylon-Iraq, in reducing some pollutants. Six fungi taxa Aspergillus flavus, A. niger, A. terrues, Candida albicans, C. krusei, and Penicillium digitatum were identified before any treatment process, whereas only four fungi species A. flavus 20%, A. niger 20%, A. terrues 10%, and P. digitatum 18% were recognized after completing the physical and chemical treatment stages. Only three taxa A. niger, A. terrues, and P. digitatum were employed to reveal their capability in treating the sewage water, which represent the biological treatment stage as the final step of the treatment processes. The results showed a considerable capability of these fungi species in decreasing many variables values such as pH, total soluble solids (TSS), electrical conductivity (EC), salinity, total alkalinity, chlorides, nitrite, and phosphate. Where, slightly low reduction was detected in TSS value in all experiments (1.1–5.9%), similarly, both EC and salinity which were decreased with low ratios (6.6%, 3.9%, respectively). Taxon A. terrues exhibited high ability in reducing the total alkalinity and chloride ions in the treated water (30.9%, 43%, respectively) in comparison with the other two fungi species. Furthermore, all three fungi species were posed high capability in decreasing nutrients, where both nitrite and phosphate ions were highly reduced (87–97% and 22.8–32.1%, respectively). Based on these findings, we suggest using other microorganisms and exploring their capacity in removing the pollutants, and revealing the ability of the above fungi taxa in removing other pollutants.

The effects of reclaimed water irrigation on the soil characteristics and microbial populations of plant rhizosphere.

In this paper, the effects of irrigation with different water qualities on the soil characteristics of 8 kinds of garden plants were analyzed. The results showed that soil pH (ranging at 7.76-8.73) had no significant difference in different soils compared with the contrast treatment. Under the reclaimed water irrigation, the content of soil total salinity, chloride ions, and water soluble sodium in soil of most plants was averagely 160.3%, 83.3%, and 67.5% higher than that of tap water, respectively. The influences of reclaimed water irrigation on soil nutrients were changed with the types of plants. The content of soil organic matter and the available potassium showed no significant differences in most plants. Compared with the tap water irrigation, the content of alkaline nitrogen in 5 plants increased (averagely 25.8%) after 5-year irrigation with reclaimed water. In terms of soil microorganism, the increase of soil microbial population, including bacteria, fungus and actinomycetes, has been promoted by different levels of reclaimed water irrigation, which is closely related with soil nutrients.

Study of Sodium Chloride Production Using Gradual Evaporation of Seawater from Nggolonio Sea, East Nusa Tenggara

Sea water as a raw material resources for the kitchen salt production, besides containing NaCl, has also containing other dissolved salts such as hygroscopic calcium and magnesium salts. The high content of other salts cause industrial NaCl has a low quality. This aim research was to find out the effect of seawater evaporation on NaCl content changes. Seawater obtained from Nggolonto, Nagekeo, NTT, was used with an initial volume of 200 mL, then it was concentrated in varying of final volume, i.e. 20, 23, 25, 27 and 29 mL. The NaCl content was calculated based on total chloride ion content, corrected toward magnesium and calcium ions content and the presence of sulphate anion. In addition, the chloride and magnesium also calcium ions content was analyzed volumetrically, while the sulphate anion was determined spectrophotometrically. The research result showed that NaCl content increase significantly up to 27 mL of final volume and was constantly afterward. Furthermore, the highest of NaCl content obtained from final volume of 29 mL was 96.01%. Nevertheless, comparing to SNI 06-0303-1989, its content was still below the standard of 98.5%.

Investigating the potential of low-grade calcined clays to produce durable LC3 binders against chloride ions attack

Utilization of limestone calcined clay cements (LC3) as a recently developed ternary blends could be a promising economic approach to reduce the environmental impacts of Portland cement production. This study presents a comparative experimental investigation between LC3 mortars and binary blends, prepared with kaolinitic calcined clays as prominent sustainable resources of supplementary cementitious materials (SCMs). In this regard, four different low to high-grade kaolinitic clays, provided from various resources, were calcined and incorporated in both binary and LC3 blends. Furthermore, the pure Portland cement and limestone Portland cement blends were also prepared to compare the results with calcined clay containing mixtures. Thermogravimetric analysis (TGA) was performed on paste samples to study the phase assemblage of systems. Besides, compressive strength, water absorption and sorptivity, total and free chloride ions penetration profiles, and chloride ions diffusion coefficients of mortar mixtures have been investigated. According to experimental results, the pozzolanic reactivity of calcined clays is not only influenced by the metakaolin content and thermal activation process, but also by the crystallinity of these materials. Besides, although the compressive strength of binary and LC3 mortars may be lower than the control mixture, but the permeability and resistance against chloride ions ingress have been significantly enhanced. Ultimately, low-grade calcined clays have been recognized as a promising resource to produce LC3 blends with adequate durability against chloride ions ingress.

Basic Study on the Durability of Mortar Containing Blast Furnace Slag Fine Powder with Different Basicity

Chloride ions penetrated reinforced concrete structures. Corrosion of reinforcing bars occurs because of cracks due to corrosion expansion, which is a problem of chloride damage deteriorating structures' performance. Blast furnace slag (from now on referred to as "BFS") is the inevitable by-product of steel product manufacturing as sustainable materials. BFS is more effective in preventing corrosion of reinforcing bars in concrete due to the denser cured and its high ability to immobilize chloride ions. Thus, the influence of BFS on the durability of mortar using BFS powder with different basicity was studied by using "Standard on Test Methods for Chloride Ion Diffusion Coefficients in Concrete" by electrophoresis (Draft) (JSCE-G571-2003)" and the total chloride ion amount was measured following JIS R 5202. The result confirmed that the immobilization performance could be greatly improved by increasing the basicity. It was remarkable in the case of air curing, a curing method for available precast products.

Chloride ion transport performance of lining concrete under coupling the action of flowing groundwater and loading

In this study, the chloride ion transport behavior of lining concrete under the coupling action of flowing groundwater and loading is investigated. The results indicate that the damage layer thickness and chloride ion concentration of the lining concrete increases with the increase of erosion age. The flowing groundwater accelerates the dissolution of the lining concrete, alkaline substances such as CH and NaOH in the lining concrete dissolve out. Under the action of the loading, the micro-cracks in the tension zone of the lining concrete continue to expand and the pores are connected to each other. Therefore, for same erosion age and distance from the lining concrete surface, the chloride ion concentration in the tensile zone is the highest under the coupling action of flowing groundwater and loading; that is followed by the action of flowing groundwater alone, and then, by the action of static groundwater. The chloride ion concentration in the pressure zone is the lowest, and the addition of fly ash and silica fume is found to help in decreasing the total chloride ion concentration and increasing the bound chloride ion concentration. In this study, a chloride ion transport model is established considering the accelerated dissolution of flowing groundwater, damage caused by loading in terms of micro-cracks and pore structure, and the effect of bound chloride ion on the total chloride ion transport, further, the rationality of the model is verified.

The applicability of different tobacco types to heated tobacco products

Heated tobacco (Nicotiana tabacum L.) products develop rapidly because of its low toxicity. In order to evaluate the industrial applicability of the existing types of characteristic tobacco as raw materials for heated tobaccos, this research ascertained differences in the main chemical compositions in tobacco leaves from different types to establish a relationship between chemical composition and sensory evaluation to select types suitable for producing heated tobaccos. Nine tobacco types (K326, Yunyan 97, Cherry-red tobacco, Han tobacco, Dao tobacco, Tiandeng tobacco, Sun-cured yellow tobacco, fresh-cut tobacco, and aromatic tobacco) planted in Yunnan Province, China were selected. Their sensory quality was evaluated by the method for sensory evaluation of heated tobaccos and chemical composition and content of aroma substances in tobacco leaves were determined. In the evaluation of sensory quality of heated tobaccos, the total score of Tiandeng tobacco was significantly higher than those of the other types, followed by Cherry-red tobacco and K326; There were significant differences in chemical composition in the nine tobacco types and the total alkaloid content in Cherry-red tobacco was notably higher than in the other tobacco types. The amounts of total sugar, reducing sugar, and starch in Han tobacco were significantly lower than other types, while the amounts of total nitrogen, potassium oxide, chloride ions, and protein were much higher than in the other tobacco types. The total amounts of polyphenols and aroma compounds in fresh-cut tobacco were significantly higher than in the other tobacco types. The contents of nornicotine, neonicotine, anatabine, and total alkaloid showed a significant positive correlation with the total sensory evaluation score. The contents of nicotyrine and 2,3-bipyridine were significantly and negatively correlated with the total sensory evaluation score. A remarkable negative correlation was found between starch content and score on irritation. Furthermore, the amounts of neochlorogenic acid, chlorogenic acid, caffeic acid, and total polyphenols were significantly and positively correlated with the total sensory evaluation score. The amounts of aldehydes and phenolic compounds had a significant negative correlation, while the amount of olefin compounds had a significant positive correlation, with the total sensory evaluation score. These chemicals in tobacco leaves can be used as in analyses screening of other suitable tobacco types, and as reference standards for selecting tobacco raw materials suitable for high-quality heated tobaccos.

Prediction of Chemical Oxygen Demand from The Chemical Composition of Wastewater by Artificial Neural Networks

In our era, many technical applications are being used. Artificial Neural Networks (ANNs) as one of the artificial intelligence tools have emerged to learn and discover a model of dynamic nonlinear. In this study, six input parameters were taken to predict the value of the Chemical Oxygen Demand (COD) in the wastewater before and after the treatment at the North Gas Company/Kirkuk, by using the standard back propagation algorithm. The network was trained with the 150 data collected from the quality indices of the untreated and treated wastewater, such as total chloride ions Cl-, nitrate ions NO3 −, phosphate ions PO4 −3, sulfate ions SO4 −2, ammonia NH3, Biochemical Oxygen Demand (BOD5) to predict one element, that is the COD. After properly training of the neural network, it was tested by using the test data, and the best results were selected by the consideration of the mean square error and the regression coefficient, where the best result appeared before wastewater treatment is 0.98235 and the best result after wastewater treatment is 0.99999. The findings of this study suggest that artificial neural networks are accurate and effective tools for predicting the COD values of treated wastewater.