Wyniki wyszukiwania - Biblioteka Nauki

1

Production of the Microfiltration Membranes of Wide Range Porosity, High Mechanical, Thermal and Chemical Stability by ,,Green’’ Fabrication Method

100%

Mkheidze N. , Gotsiridze R. , Mkheidze S. , Tenieshvili K.

Ecological Engineering & Environmental Technology

|

2023

|

tom Vol. 24, iss. 8

301--310

EN

In the modern technological processes, the microfiltration membranes are used for removal of the suspended particles, colloids and microorganisms from the liquid solutions, as well as for use of the biologically active substances. Their demand at the world market rises day by day and if their production from the polymeric materials having wide range porosity, as well as high mechanical, thermal and chemical stability is provided the field of their use will expand even more. Proceeding from all above, fluoroplastic (F-4) was chosen, as the thermo- and chemically stable polymer used in medicine and food industry for production of the wide range porosity microfiltration membranes. The methods used for modification of membranes in the process of the research do not require any toxic solvents or complicated appliances or high power inputs. The thermo- and chemical stability of the produced membranes allows their multiple use in the process of filtration, which also allows implementing the principles of ,,green” technology. Pore sizes distribution of membranes was researched on Porometer by using the method of capillary flow porometry in compliance with the standards of ACTM F-316-03, which rules out using of the toxic (or hazardous substances), ex. mercury.

2

Production of Potassium-Enriched Fertilizer Using the Complex Sorption and Membrane Technology

88%

Mkheidze N. , Gotsiridze R. , Kontselidze L. , Mikeladze Z. , Kharazi N.

Ecological Engineering & Environmental Technology

|

2022

|

tom Vol. 23, iss. 2

199--205

EN

The production of potassium-containing fertilizer using improved, complex method was researched. Cheapness and availability of the raw material (the natural zeolite, clinoptilolite from Dzegvi and Tedzami mines is used as a substrate and seawater – as a source of potassium ions) make this method very interesting and prospective for the countries with clinoptilolite stocks, located in the seaside regions and engaged in agrarian industry (Georgia, Greece, Romania, Bulgaria). It includes two technological processes: sorption and membranes ones. At the first stage, for intensification purpose electrodialysis was used for concentration of sea water. The optimal parameters for concentration of sea water were matched using the electrodialysis apparatus produced in the Institute workshop. In the produced concentrate of sea water, the index of potassium-ion concentration exceeds 4, being twice higher than the natrium-ion concentration index. At the second stage, selection of sea water ions was provided on the natural zeolite by so called dual-temperature ion exchange method: during sorption of potassium by clinoptilolite at low temperature the other ions pass into filtrate. The received potassium-enriched zeolite is a new type fertilizer: potassium containing therein passes into soil "as needed", when soil is impoverished.

3

Cost-Effective Remediation of Petroleum-Contaminated Waters Using Locally Sourced Wood Sawdust

88%

Mkheidze N. , Davitadze R. , Gotsiridze R. , Kiknadze N. , Megrelidze N.

Journal of Ecological Engineering

|

2024

|

tom Vol. 25, nr 5

208--218

EN

The increasing environmental pollution resulting from oil transportation, especially through pipelines such as the Baku-Supsa in Georgia, calls for the development of advanced wastewater purification technologies. This study investigates the use of wooden sawdust for the purification of oil-contaminated waters, aiming to utilize locally available residual natural materials for cost-effective environmental remediation. A comprehensive experimental methodology was adopted, involving thirteen types of plant-derived sawdust as sorbents to evaluate their oil sorption capacities under static and dynamic conditions. The effectiveness of these sorbents was assessed by their ability to lower the concentration of petroleum hydrocarbons in contaminated water, focusing specifically on the influence of sorbent particle size, contact duration, and the initial concentration of oil contaminants. The physicochemical characteristics of Azeri Light crude oil were detailed, and the sorption mechanism was scrutinized using gas-liquid chromatography to ascertain the fractional composition of the oil absorbed by the sawdust. Sawdust from Cryptomeria exhibited the highest oil sorption capacity, successfully absorbing 31.6 grams of oil per 100 milliliters of sorbent. Sawdust from Eucalyptus and Oak also displayed considerable sorption capabilities. The f indings indicate that decreasing the particle size of the sawdust significantly enhances its capacity to sorb crude oil. Furthermore, steam-contact pre-treatment of the sawdust markedly increased its oil sorption capacity by 11% and tripled its efficacy in purifying oil-contaminated water. The results highlight the potential of employing locally sourced wooden sawdust, especially from Cryptomeria, as an efficient, sustainable, and cost-effective sorbent for cleaning oil-contaminated waters. The improved sorption capacity achieved through steam-contact pre-treatment presents a viable strategy for enhancing the performance of sawdust sorbents. This research contributes to the advancement of eco-friendly and economically feasible solutions for reducing water pollution caused by oil and its derivatives, emphasizing the critical role of sorbent selection and pre-treatment in refining purification processes.

4

Improvement of Technological Modes of Electrodialysis Apparatus for Treatment of Chromium-Containing Waste Waters

88%

Mkheidze N. , Gotsiridze R. , Kontselidze L. , Mkheidze S. , Davitadze R.

Ecological Engineering & Environmental Technology

|

2021

|

tom Vol. 22, iss. 5

47--54

EN

The wastewaters of galvanizing plants contain toxic heavy metals, which causes pollution of the environment and endangers it. The aim of the present study includes concentration of chromium (VI) ions from chromium plating wastewaters, purification of wastewater and its reuse for development of waste-free technological cycle. This study was carried out with the pilot electrodialysis apparatus designed by the authors and produced in the Institute engineering workshop using real plating rinse water of the plating shop. The authors obtained desalinated water which may be recirculated in rinsing bath and chromium salts concentrate that can be applied in chromium plating bath after correction. As a result of the conducted experiment, the ion-exchange membranes resistant to "poisoning" with chromium (VI) ions and stable in the process of regeneration were selected and the technological modes for stable operation of apparatus matched.