scholarly journals REDUCTION OF THE LEVEL OF TECHNOGENIC HAZARD NEGATIVE EFFECT OF SEDIMENTS OF URBAN WASTE WATER ON THE ENVIRONMENT WITH HUMIC SUBSTANCES

2021 ◽  
pp. 70-74
Author(s):  
Stanislav Dushkin
Keyword(s):  
Heavy Metals ◽  
Humic Substances ◽  
Municipal Wastewater ◽  
Negative Impact ◽  
Wastewater Sludge ◽  
Ecological Problem ◽  
Urban Wastewater ◽  
Water Object ◽  
Negative Effect ◽  
Methods Of Treatment

The article discusses the issues of reducing the level of technogenic safety of the negative impact of urban wastewater sludge on the environment by removing heavy metals using humic substances. It is noted that the technogenic and ecological problem requires an urgent solution through the formation of new effective methods of treatment (neutralization and dehydration) and further disposal of urban wastewater sludge. Silt sites are a source of pollution of soil, groundwater and surface water object and air. A new method for removing heavy metals from municipal wastewater sludge using humic substances has been developed. It was found that humic substances have a sorption capacity in relation to heavy metals. As a reagent for removing heavy metals from urban wastewater sludge, it is proposed to use the product of processing lignite and peat with alkali using a carbon-alkali reagent, which makes it possible to reduce the concentration of heavy metals to such concentrations that the sludge can be used as fertilizer in agriculture.

scholarly journals Novel and Eco-Friendly Washing Agents to Remove Heavy Metals from Soil by Soil Washing

2018 ◽  
Vol 2 (2) ◽  
Author(s):  
Zygmunt Mariusz Gusiatin
Keyword(s):  
Heavy Metals ◽  
Organic Matter ◽  
Humic Substances ◽  
Plant Extracts ◽  
Environmental Risk ◽  
Soil Washing ◽  
Field Scale ◽  
Remediation Technology ◽  
Low Weight ◽  
Negative Effect

Soil washing is a remediation technology that can efficiently remove heavy metals from soil and decrease environmental risk. Due to the negative effect of conventional washing agents on soil quality, their replacement with novel, eco-friendly agents is necessary. This paper gives a basic presentation of the most promising washing agents that have high potential to be used at field scale: biodegradable chelators, biosurfactants, plant extracts, and dissolved organic matter including soluble low-weight organic matter and soluble humic substances. The main advantages of these novel agents are highlighted

PLANTER BOX RAINGARDEN FOR ZINC REMOVAL FROM STORM WATER

2020 ◽  
Vol 7 (2) ◽  
Author(s):  
Mohammad Ramezanianpour ◽  
Alex Levien ◽  
George Ritchie
Keyword(s):  
Heavy Metals ◽  
Water Quality ◽  
Negative Impact ◽  
Removal Rate ◽  
Main Idea ◽  
Run Off ◽  
Vertical Hydraulic Conductivity ◽  
New Development ◽  
High Removal Rate ◽  
Methods Of Treatment

Urbanization creates problems for the natural water systems, such as an increase in run-off volume due to the impervious surfaces and a negative impact on groundwater recharge. These changes and exposure to contaminants such as suspended/dissolved solids and heavy metals severely degrade stormwater quality. In Christchurch, heavy metals such as zinc found in run-off, which is mainly sourced from galvanized roofing. The main idea of this research is to solve run-off issues at the source, along with the construction phase. This idea is aligned with the NZ's Unitary Plan to keep rainwater run-off after a new development equal or less than the run-off that occurred before the development. Different methods of treatment for roof run-off were evaluated in this research to propose a sustainable solution followed by an assessment. A multi-layered planter box raingarden was selected since it helps to landscape, improve water quality, and perform as an attenuation device. The research concentrated on maximizing water quality while maintaining a required flowrate. The planter box raingarden performed at a low vertical hydraulic conductivity rate of 164 mm/hr and achieved a high removal rate for heavy metals. The removal rate for dissolved zinc and total zinc was 99.7% and 99.1%, respectively. The results explained that the planter box raingarden performs well as an attenuation device while adsorb and filter contaminants remarkably.

scholarly journals Occurrence and Fate of Heavy Metals in Municipal Wastewater in Heilongjiang Province, China: A Monthly Reconnaissance from 2015 to 2017

Water ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 728 ◽  
Author(s):  
Peng Du ◽  
Lingrong Zhang ◽  
Yuntao Ma ◽  
Xinyue Li ◽  
Zhenglu Wang ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Urban Areas ◽  
Municipal Wastewater ◽  
Flow Analysis ◽  
Material Flow Analysis ◽  
Wastewater Sludge ◽  
County Level ◽  
Heilongjiang Province ◽  
Municipal Wastewater Treatment ◽  
Modeling Tools

As one of the major sources of pollutions in the environments, effluents from municipal wastewater recently became a hot topic. This study quantified monthly county-level releases of five heavy metals, i.e., lead (Pb), cadmium (Cd), chromium (Cr), arsenic (As), and mercury (Hg), from municipal wastewater into the environment in the Heilongjiang Province of China, based on sampling, measurement, and modeling tools. Wastewater samples were collected from 27 municipal wastewater treatment plants (MWTPs) in 15 county-level cities of Heilongjiang every month from 2015 to 2017. The concentrations of five heavy metals were analyzed in both influents (Pb: 160 ± 100 μg/L; Cd: 15 ± 9.0 μg/L; Cr: 170 ± 64 μg/L; Hg: 0.67 ± 1.5 μg/L; As: 6.2 ± 4.8 μg/L) and effluents (Pb: 45 ± 15 μg/L; Cd: 5.2 ± 5.1 μg/L; Cr: 57 ± 13 μg/L; Hg: 0.28 ± 0.12 μg/L; As: 2.6 ± 1.4 μg/L). The removal ratios of the five heavy metals ranged from 50% to 67%. Inflow fluxes of Pb, Cr, and Cd displayed increasing trends first then decreased after reaching a maximum value, whereas those of Hg and Pb remained stable. Material flow analysis reveals that constructions of MWTPs are conducive to significantly reduce the releases of heavy metals from urban areas into the aquatic environment in the study area. Additionally, municipal wastewater sludge (used as fertilizer or spread on the land) could be a significant source of heavy metals in the land.

scholarly journals Anaerobic co-digestion of municipal wastewater sludge and restaurant grease

2011 ◽  
Vol 46 (4) ◽  
pp. 290-299 ◽  
Author(s):  
Zengkai Liu ◽  
Ian D. Buchanan
Keyword(s):  
Municipal Wastewater ◽  
Loading Rate ◽  
Energy Content ◽  
Biogas Production ◽  
Oxygen Demand ◽  
High Energy ◽  
Wastewater Sludge ◽  
Methane Yield ◽  
Organic Loading Rate ◽  
Negative Effect

Co-digestion has drawn much attention because of its potential to increase biogas production among other benefits. Restaurant grease has high energy content and methane production potential and so is a promising substrate for co-digestion with municipal wastewater sludge. Anaerobic co-digestion of municipal wastewater sludge and restaurant grease was investigated at laboratory-scale under mesophilic conditions (37 °C). Increasing the chemical oxygen demand (COD) loading rate of the test digester by 387% (organic loading rate 4.235 kg VS/m3/d) relative to the control digester led to a 467% increase in daily biogas production, a 25.2% increase in methane yield (based on volatile solids (VS) destruction), a 29.8% increase in COD removal and a 27.2% increase in VS reduction. The biogas methane content ranged from 62.6 to 66.2% (v/v). No negative effect of the grease addition was observed in the test digester performance under the conditions investigated. The increases in biogas production and methane yield indicated enhanced digestion performance. In addition, partial alkalinity and pH proved to be good indicators of digester stability.

scholarly journals An investigation of qualitative variations of groundwater resources under municipal wastewater recharge using numerical and laboratory models, Nazarabad plain, Iran

2021 ◽  
Author(s):  
Nezhla Amiri ◽  
Mohammad Nakhaei
Keyword(s):  
Heavy Metals ◽  
Municipal Wastewater ◽  
Groundwater Resources ◽  
Column Experiment ◽  
Actual Condition ◽  
Alkaline Soil ◽  
Urban Wastewater ◽  
Long Run ◽  
Wastewater Recharge ◽  
Laboratory Models

AbstractMunicipal wastewater irrigation induces elevated concentrations of heavy metals in the soil which their further leaching leads to groundwater contamination in the long run. In this study, both column experiment and 5-year prediction modeling using HYDRUS-1D were conducted to investigate the probable adsorption and transport of 10 different metals including As, Ba, Cr, Cu, Mo, Ni, Pb, Rb, Sr, and Zn in an alkaline soil from Nazarabad plain in Iran which has been irrigated with treated urban wastewater for several years. The obtained results revealed that reaching the equilibrium rate for the mentioned elements during 1825 days (= 5 years) was as follows: Mo > Cr > Rb > Zn > Ni > Ba> Sr > Pb > As> Cu. The finding implies that molybdenum (Mo) and copper (Cu) are the most mobile and the most adsorbent heavy metals in the soil, respectively. Higher mobility poses the greater potential risk of leaching into groundwater resources. Overall, experimental and numerical modelings had good accordance and were capable of describing the actual condition.

PD-L1 and survival in oral cavity squamous cell carcinoma

2020 ◽  
Vol 25 (4) ◽  
pp. 287-294
Author(s):  
S. I. Kutukova ◽  
N. P. Beliak ◽  
G. A. Raskin ◽  
M. S. Mukhina ◽  
Yu. V. Ivaskova ◽  
...  
Keyword(s):  
Squamous Cell Carcinoma ◽  
Oral Cavity ◽  
Cell Carcinoma ◽  
Tumor Cells ◽  
Squamous Cell ◽  
Immune Cells ◽  
Negative Impact ◽  
Progression Free Survival ◽  
Negative Effect ◽  
Effect Of Pd

Relevance. Prognostic value of PD-L1 expression in oral cavity squamous cell carcinoma (OCSCC) and its effect on survival is still controversial. It should be to determine the prognostic role of PD-L1 expression on tumor and immune cells of OCSCC and assess their effect on overall survival (OS) and progression-free survival (PFS).Materials and methods. A prospective study included 145 patients, first diagnosed with OCSCC. PD-L1 expression on tumor and immune cells, infiltrating tumor and its microenvironment, was assessed in all tumor samples by IHC, CPS was calculated. Cut-off values were determined by ROC analysis for identification of PD-L1 expression effect on OS and PFS.Results. Most patients with oral mucosa squamous cell carcinoma showed positive expression of PD-L1 on tumor (77.2%) and immune cells (92.4%). The median PD-L1 expression on tumor cells was 13.5% [1.0-40.0], the median PD-L1 expression on immune cells was 5.0% [1.0-11.0], and the median CPS – 18.0 [3.0-7.8]. Univariate and multivariate analyses revealed a significant negative effect of PD-L1 expression on immune cells ≤ 7% on OS (HR 0.66; 95% CI 0.45-0.93; p = 0.0498); PD-L1 expression in tumor cells ≤ 15% (HR 0.65; 95% CI 0.43-0.98; p = 0.0416) and CPS ≤ 21 (HR 0.62; 95% CI 0.44-0.92; p = 0.0183) for PFS. PD-L1 expression in tumor cells ≤ 6% (HR 0.71; 95% CI 0.47-1.08; p = 0.1096) and CPS ≤ 7 (RR 0.67; 95% CI 0.44-1.01; p = 0.0575) had a confident tendency to negative impact on OS.Conclusion. Positive PD-L1 expression in tumor and immune cells as well as CPS are effective additional factors in the prognosis of the disease course, OS and PFS in patients with OCSCC.

Physical properties of dewatered wastewater sludge for landfilling

1996 ◽  
Vol 34 (3-4) ◽  
pp. 533-540 ◽  
Author(s):  
A. Koenig ◽  
J. N. Kay ◽  
I. M. Wan
Keyword(s):  
Shear Strength ◽  
Hong Kong ◽  
Municipal Wastewater ◽  
Compressibility Factor ◽  
Wastewater Sludge ◽  
Municipal Wastewater Treatment ◽  
Intrinsic Resistance ◽  
Coefficient Of Consolidation ◽  
Minimum Requirement ◽  
Geotechnical Stability

In the context of landfilling dewatered wastewater sludge in Hong Kong, with landfills up to 140 m high, one of the most significant properties of sludge is its physical nature with regard to moisture characteristics and associated geotechnical stability. Commonly, lower limits are set on total solids content, but no geotechnical stability criteria are applied with the exception of Germany where a minimum requirement for vane shear strength is set at 25 kN/m2. The purpose of this study was to determine and evaluate dewatered wastewater sludge from three Hong Kong municipal wastewater treatment plants with regard to the following physical and geotechnical properties: (i) vane shear strength; (ii) consolidation characteristics such as compression index, compressibility factor, coefficient of consolidation and compressibility coefficient; and (iii) hydraulic characteristics such as permeability and intrinsic resistance. Although dewatered sludge exhibits quite different characteristics as compared to soils, predictive logarithmic relationships may be established between various properties which are consistent with the critical state model for soils, conventional filtration and consolidation theory. Such representation provides a valuable basis for understanding the sludge characteristics and behaviour to landfill design.

Hydrothermal liquefaction of municipal wastewater sludge and nutrient recovery from the aqueous phase

Biofuels ◽  
2021 ◽  
pp. 1-6
Author(s):  
Vinod Kumar ◽  
Krishna Kumar Jaiswal ◽  
Mikhail S. Vlaskin ◽  
Manisha Nanda ◽  
M. K. Tripathi ◽  
...  
Keyword(s):  
Aqueous Phase ◽  
Municipal Wastewater ◽  
Hydrothermal Liquefaction ◽  
Wastewater Sludge ◽  
Nutrient Recovery
Sign in / Sign up

Export Citation Format

Share Document