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A novel ternary flocculant was prepared by a simple compounding method to achieve efficient and rapid mud-water separation. This paper aims to discuss the possible mud-water separation mechanism.

This experimental study aims to investigate the effects of different types of flocculants on the separation of waste mud water and the degradation of flocculants in the supernatant. The flocculating component, the ratio of the flocculating accelerator to the flocculant and the addition amount of the novel ternary flocculant were optimized.

The experimental results show that the composition of the new ternary flocculant is cationic polyacrylamide (CP-02), grafted starch (GS-501) and flocculation sedimentation accelerator, the best effect, the mass ratio is 1:0.5: 0.75. According to 0.25:1 (volume ratio), the new ternary flocculant is pre-configured into a solution with a concentration of 3 kg/m³ to achieve efficient and rapid mud-water separation.

The new ternary flocculant is used for the separation of mud and water in the underground continuous wall waste mud, improving the level of civilized construction.

The purpose of this study is to investigate the authors' previously prepared and fully characterized poly (methacrylamide)-chitosan nanoparticles (CNPs) graft copolymer having 50.2% graft yield with respect to flocculation efficiency for ferric laurate aqueous dispersions. This was done to compare the ability of the latter cheap, biodegradable and ecofriendly hybrid natural-synthetic polymeric substrate as a flocculant in comparison with higher cost, nonbiodegradable and harmful polyacrylamide as a well-known synthetic flocculant counterpart.

The graft copolymerization process was carried out at 450°Cfor 120 min using (1.0 g) CNPs, methacrylamide (1.5 g), 100 mmol/l potassium chromate and 80 mmol/l mandelic acid. Fourier transform infrared spectroscopy, thermogravimetric analysis, elemental analysis and specific viscosity were used to characterize and analyze the resultant copolymer. The flocculation efficiency was conferred in terms of transmittance % and weight removal %. The main factors influencing the flocculation process, such as flocculent dose, flocculation medium pH, stirring speed, flocculation temperature and grafting extent, were comprehensively discussed.

The flocculation efficiency of the prepared copolymers revealed the following findings: increased by increasing the flocculant dose, pH, temperature and stirring speed to a maximum values denoted at 30 ppm, 6.0, 30°C and 50 r/min, respectively, then decreased thereafter; increased by increasing the extent of grafting within the range studied; showed a comparable flocculation efficiency in comparison with polyacrylamide as a synthetic polymeric flocculent; and, finally, a preliminary bridging mechanism representing the attraction between the anionic suspended particles ferric laurate and cationic poly (MAam)-CNPs graft copolymer has been projected.

The advancement addressed here is undertaken with using the authors’ poly (MAam)-CNPs graft copolymers having different extent of grafting (a point which is not cited in the literature especially for the authors’ prepared copolymer) as a hybrid natural-synthetic polymeric substrate as a flocculant for ferric laurate aqueous dispersions in comparison with the high cost and nondegradable polyacrylamide synthetic flocculant.

The purpose of this paper is to model the corrosion rate behavior for two ferrous materials, carbon steel AISI 1020 and stainless steel AISI 304, immersed in ferric sulfate and ferric chloride solutions using D-optimal design with response surface methodology.

Experimental design addresses two factors (concentration and contact time) with multilevel categories, in order to predict and compare the corrosion rates of the studied materials immersed in flocculants solutions. A corrosion rate of specimens was calculated from mass loss determinations.

The authors used a polynomial model to fit the experimental values, thereby predicting significantly higher corrosion rates in ferric chloride solutions, as compared to ferric sulfate.

The authors propose a high fidelity model of the corrosion rate of each carbon steel and stainless steel material using D-optimal design with a response surface method (RSM).

In this study, the removal of a series of acid dyes by hybrid polymer adsorbent was investigated. Textile industry wastewater is mainly consisted of suspended solid particles and organic compounds with complex and nondecomposable structures. Treatment of such wastewaters has received much attention by researchers because of high water consumption and the presence of various chemical compounds, especially dyes. The use of polymers has recently attracted much attention for the treatment of textile wastewaters. According to the literature, hybrid polymers are highly capable of adsorbing dyes. In this research work, polyacrylamide/iron sulfate (PAM-FeSO₄) hybrid polymer was successfully synthesized through solution polymerization of acrylamide with ammonium persulfate and sodium thiosulfate and gradual addition of iron sulfate. The hybrid polymeric adsorbent was then used for removing acidic dyes with different chemical structures.

The effects of various experimental conditions and parameters, such as initial concentrations of dye and adsorbent, on the adsorption capacity of the adsorbent were investigated. The dye concentration was measured by an UV–vis spectrophotometer. The adsorption equilibrium was studied by plotting adsorption isotherms. The experimental data was fitted to Langmuir and Freundlich isotherms.

The adsorption experiments indicated that the PAM-FeSO₄ hybrid polymer has a high adsorption capacity (117.64 mg g⁻¹ for the Orange ІІ and 80.64 mg g⁻¹ for the Sunset Yellow [SY]) when 80 mg of adsorbent was immersed in the dye solution (1 g L⁻¹) with a pH of 11 at 25°C. The analysis of the equilibrium isotherms using the Langmuir and Freundlich isotherms indicated that the Langmuir model fit well to the experimental data.

To the best of the authors’ knowledge, this study is original. The removal of acid dyes such as Sunset Yellow and Methyl Orange using PAM-FeSO₄ hybrid polymer as flocculant was done for the first time.

Chitin Derived Coag-flocculant (CDC), is a cheap, abundant and eco-friendly deacetylated cationic polymer applied in this study at a pilot scale for the treatment of Brewery Effluent (BRE). The study investigates the influence of varying BRE pH on the coag-flocculation kinetics and behavior of the aggregation process at varying CDC dosages. The best coag-flocculation performance is recorded at rate constant, K_m, of 0.0003 l/mg·min, half life, τ1/2, of 0.6846 min, pH of 4, dosage of 100 mg/l and efficiency, E (%) of 99.8791. Minimum efficiency (%) > 96 was achieved at 3 minutes of coag-flocculation, establishing CDC as an effective water treatment agent at the conditions of the experiment.

The purpose of this paper was to promote the use of residual moringa seed powder (RMSP) for the enhancement of cereal-based products. RMSP is usually discarded after seed-oil extraction. This work also promotes zero-waste and rheological approaches.

In search of novel and sustainable food products with high nutritional value, cold-pressed Moringa oleifera Lam. seeds residue (RMSP) was used for incorporation in muffin formulations. Wheat flour was partially substituted (0%, 1%, 3%, 5%, 7% and 9%) by RMSP. Sodium (Na), calcium (Ca) and iron (Fe) contents were quantified through atomic absorption spectrometry; protein, through the Kjeldahl method followed by AACC Method 46–13.01; and, fat content, by a modified version of AACC Method 30–25.01a. Analysis of variance (ANOVA) and Tukey tests were performed to determine significant differences between formulations at 95% reliability using Minitab® software. Furthermore, simple viscosity studies of the dough mixture were carried in a Brookfield DV-III Ultra Rheometer; Matlab® curve-fitting tool was used for obtaining the best non-Newtonian equation that modeled experimental data. Subsequently, computational fluid dynamics (CFD) simulations of non-Newtonian fluids along a segmented pipe were carried out in Comsol Multiphysics® software to depict the importance of modeling non-Newtoning fluids for downstream processes.

RMSP significantly (p < 0.0001) increased protein and Fe content for the 7% and 9% formulations; it dramatically changed Na and Ca content in all formulations, while fat remained constant.

The development of this type of product is an opportunity for communities that grow and harvest moringa as well as for food industries which can take advantage of moringa by-products for several subsequent processing.

For the first time, it was found that dough formulations with RMSP presented a pseudo-plastic and thixotropic behavior. In addition, the use of lignocellulosic by-products such as RMSP incorporates an added value to food products. In this case, it was demonstrated that moringa seed residue enhanced nutritional value to muffins and provided coagulant/flocculant action, which is essential during dough preparation.

Coag-flocculation behavior of Brachystegia eurycoma coagulant (BEC) in respect of pH variation in coal washery effluent has been investigated at room temperature using various dosages of unblended BEC. Coag-flocculation parameters such as order of reaction α, rate constant (K and Ks), coagulation period, τ_1/2 e.t.c were determined. Turbidity measurement was employed using the single angle nephelometric method while BEC processing was based on work reported by Adebowale and Adebowale. Maximum parameter values are recorded at K of 6.6667×10^-3m³/kg.s; dosage of (0.2 and 0.4kg/m³), pH2 and τ_1/2 of 1.7293s while the minimum values are recorded at 5.00×10^-4m³/kg.s, dosage of 0.3kg/m³, pH 6 and τ_1/2 of 23.0572s. Minimum value of coag-flocculation efficiency is >98%; thus establishing BEC as a potential effective coag-flocculant. Parameters obtained lie within the range of previous works and confirm that the theory of perikinetics holds for coag-flocculation of the coal washery effluent using BEC at the experimental conditions.

The purpose of this paper is to compare well‐known technologies of sludge utilization on the basis of energy and economical balances of real processes. The calculations are based on pilot tests in the Central Waste Water Treatment Plant (CWWTP) in Prague, the biggest waste water treatment plant in the Czech Republic.

A key issue for the comparison of mass and energy flow of sludge management is the attainable level of sludge dewaterability. Results of dewatering of anaerobic digested sludge are available from real applications since most sewage plants use digesters. The existing limited knowledge about mixed raw sludge (MRS) dewaterability have driven authors to make pilot tests targeted to establishment of an attainable level of MRS dewaterability. To get as close results as possible even anaerobic stabilized sludge was dewatered and various other data were collected to obtain a comprehensive data set for energy balance of the sludge management calculation. The pilot tests took place at CWWTP in 2005. Measured data were used to calculate energy balance of a number of different sludge managements.

To produce self‐reliant combusting sludge, a dry matter content of 35‐45 per cent for MRS and 45‐55 per cent for digested sludge has to be achieved by means of dewatering and potentially drying. In recent measurements at CWWTP a dry matter content of about 33 per cent was achieved by dewatering of MRS. This value is very close to the range of the dry matter content at which a self reliant combustion can be expected.

This comparison together with investment cost analysis should be one of the most important parameters in case of design a new or revamp an old waste water treatment plant.

The paper provides results from pilot tests at CWWTP together with three different energy balances comparison.

The purpose of this paper is to examine inspiring ideas in which Japanese companies are finding innovative ways to tap into base of the pyramid (BOP) markets to increase their profit while simultaneously reducing poverty and contributing to BOP society.

This paper examines a potential and some issues of Japanese business in BOP market through case analysis of Yakult Honsha Co Ltd and Nihon Poly‐Glu Co Ltd.

The paper reveals that Japanese companies have a particular aptitude and strength for BOP business. The paper have three findings: Japanese company has a source of BOP business; Japanese companies have aptitude and strength for BOP business; and the time is ripe for Japanese companies to break into the BOP market.

There are few cases of Japanese companies which are engaging in BOP business. It could be kind of difficult to get a general result on Japanese business.

This paper shows that a high potential for Japanese companies to succeed in BOP market and some issues facing Japanese companies.

This paper is the first which analyzed some cases of Japanese BOP business and revealed a high potential of Japanese companies for BOP business.

To document the drinking water component of the humanitarian response to the Great Sumatra‐Andaman earthquake of December 26, 2004, including a focus on the promotion of household water treatment (HHWT)/safe storage to minimize the spread of diarrhoeal disease.

Firsthand accounts of the response effort, interviews, and literature review.

The combined efforts to mobilize a drinking water response were timely, comprehensive and effective. HHWT/safe storage efforts (other than the continued promotion of boiling) appeared to play only a secondary role in the initial response to the disaster for a variety of reasons.

The enormity of this disaster and the unprecedented scale of the relief effort limit the broad lessons that can be learned at this time.

Shows that there is a clear need to continue to take steps to minimize the risks of waterborne diseases following natural disasters, develop and disseminate practical solutions for the special circumstances associated with tsunamis, including saline water intrusion, clarify the conditions under which proven approaches to HHWT may be useful in emergencies and assess their role in the medium‐ and long‐term response, improve water quality and surveillance without compromising emphasis on water quantity, take advantage of the enormous resources committed to the tsunami response to make effective and sustainable improvements in water, sanitation and hygiene in the affected areas, and document experiences from the tsunami response, distil the lessons learned, disseminate the results and develop guidelines to inform future actions.