The impact of chemical additives on the process of biodegradation of oil products /

Many modern technologies for treatment of soil polluted with oil products are developed through creation of new and efficient bio-agents that help to degrade oil products. Another trend in development of new technologies aims to speed up the growth of soil microorganisms, this way accelerating biodegradation of oil products without the help of introduced microorganisms. The biodegradation of diesel fuel and heavy fuel oil was tested in the soil using chemical additives (oxidizing agents). The tests aimed to ascertain the impact of H2O2, KMnO4 and MnSO4 on residual concentrations of heavy fuel oil and diesel fuel, and the total number of microorganism colonies, as well as the number of oil-oxidizing microorganism colonies in the soil. After the statistical analysis of the data obtained during the experiment, a statistically significant (p <0.05) difference between control samples and samples with introduced chemical additives was obtained both in the soil contaminated with heavy fuel oil and diesel fuel. It was determined that use of KMnO4 as an oxidizing agent in the soil contaminated with heavy fuel oil, resulted in 3 times less statistically significant residual value of the heavy fuel oil concentration than in the control samples; however, no statistically significant difference was found between oxidizing agents (potassium permanganate and hydrogen peroxide). In cases where soil is contaminated with diesel fuel, there is a significant difference between KMnO4 and H2O2, which shows that potassium permanganate has a bigger impact on the degradation of diesel fuel than hydrogen peroxide. The residual concentration of diesel fuel in the samples with KMnO4 was 3 times less statistically significant than in the samples with H2O2, and 5 times less than in the control samples. The use of both – KMnO4 and MnSO4 – created more favourable conditions for biodegradation of diesel fuel and heavy fuel oil in the soil. A positive growth of microorganisms using Mn of different valence was observed during the entire course of experiment. Various chemical additives could be used in the technological process of biotreatment, when soil is contaminated with oil products. Santrauka Daugelis šiuolaikinių užteršto naftos produktais dirvožemio valymo technologijų vystosi kurdamos naujus ir efektyvius, naftos produktus skaidančius bioagentus. Kita naujų technologijų vystymosi kryptis – neįnešant mikroorganizmų, pagreitinti dirvožemyje jau esančių mikroorganizmų vystymąsi, paspartinant naftos produktų biodegradaciją. Dyzelino ir mazuto biodegracija buvo tirta dirvožemyje, naudojant cheminius priedus (oksidatorius). Buvo tirta H2O2, KMnO4 ir MnSO4 įtaka mazuto ir dyzelino liekamosioms koncentracijoms, bendram ir naftą oksiduojančių mikroorganizmų skaičiui dirvožemyje. Atlikus statistinę eksperimento metu gautų duomenų analizę, tiek grunte su mazutu, tiek su dyzelinu buvo nustatytas statistiškai reikšmingas (p<0,05) skirtumas tarp liekamujų naftos produktų koncentracijų tiek kontroliniuose bandiniuose, tiek bandiniuose, kuriuose buvo įterpti cheminiai priedai. Mazutu užterštame grunte nustatyta, kad kaip oksidatorių panaudojus KMnO4 likutinė mazuto koncentracijos reikšmė buvo tris kartus statistiškai reikšmingai mažesnė nei kontroliniuose bandiniuose, tačiau nėra statistiškai reikšmingo skirtumo, kurį oksidatorių (ar kalio permanganatą ar vandenilio peroksidą) naudoti. Kai gruntas užterštas dyzelinu, tarp KMnO4 ir H2O2 naudojimo yra statistiškai reikšmingas skirtumas. Tai rodo, kad kalio permanganatas turi didesnę įtaką dyzelino degradacijai negu vandenilio peroksidas. Bandiniuose su KMnO4 liekamoji dyzelino koncentracija buvo tris kartus statistiškai reikšmingai mažesnė negu bandiniuose su H2O2 ir penkis kartus mažesnė nei kontroliniuose bandiniuose. Tiek bendrą, tiek naftą oksiduojančių mikroorganizmų skaičių teigiamai paveikė cheminiai priedai. Tiek grunte su mazutu, tiek su dyzelinu buvo nustatytas statistiškai reikšmingas (p<0,05) skirtumas tarp mikroorganizmų kiekio kontroliniuose bandiniuose ir bandiniuose, į kuriuos buvo įterpti oksidatoriai. Tiek KMnO4, tiek MnSO4 naudojimas sudarė geresnes sąlygas biodegraduoti dyzelinui ir mazutui dirvožemyje. Viso eksperimento metu stebėtas teigiamas mikroorganizmų augimas, naudojant skirtingo valentingumo Mn (druskas). įvairūs cheminiai priedai galėtų būti naudojami biovalymo technologiniame procese, kai dirvožemis yra užterštas skirtingais naftos produktais. Резюме Большинство современных технологий по очистке грунта от нефтепродуктов развиваются в направлении создания новых, более эффективных биоaгентов, способствующих деструкции нефтепродуктов в грунте. Альтернативное направление развития данных технологий заключается в ускорении размножения микроорганизмов,присутствующих в грунте, и тем самым ускорении биодеградации нефтепродуктов. Исследование биодеградациидизельного топлива и мазута в грунте проводилось при использовании химических добавок (оксидаторов). Проводилось исследование влияния H2O2,KMnO4 и MnSO4 на изменение конечной концентрации дизельного топливаи мазута, а также на изменение общего количества нефтеусваивающих микроорганизмов. Статистический анализэкспериментальных данных показал, что в грунте с мазутом, так же, как и в грунте с дизельным топливом, существует статистически значимая разница (p < 0,05) между концентрациями нефтепродуктов в контрольных пробахи в пробах грунта с содержанием химических добавок. Установлено, что в грунте, загрязненном мазутом, во время использования оксидатора KMnO4значение конечной концентрации нефтепродукта было в 3 раза статистически менее значимое, чем в контрольных пробах, однако нет статистически значимой разницы, какой оксидаториспользовать – H2O2 или KMnO4. В случае загрязнения грунта дизельным топливом было установлено, что между KMnO4 и H2O2 существует статистически значимая разница, что позволяет утверждать, что KMnO4имеет большее влияние на процесс деградации нефтепродукта, чем H2O2. В пробах с KMnO4статистически значимая разница конечной концентрации дизельного топлива в грунте была в 3 раза меньше, чем с H2O2, и в 5 раз меньше, чем в контрольных пробах. Химические добавки положительно воздействовали и на общее количество микроорганизмов, ина количество нефтеусваивающих микроорганизмов. Использование KMnO4 и MnSO4 способствовало улучшениюусловий биодеградации дизельного топлива и мазута в грунте. Во время всего эксперимента, используя соли Mnразной валентности, наблюдался постоянный рост количества микроорганизмов. На основании результатов данного исследования можно рекомендовать различные анализированные добавки к использованию в технологическом процессе биологической очистки грунта от различных нефтепродуктов. Reikšminiai žodžiai: dirvožemio valymo technologijos, biodegradacija, mazutas, dyzelinas, cheminiai priedai, mikrobiologinis aktyvumas Ключевые слова: технологии по очистке грунта, биодеградация, дизельное топливо, мазут, химические добавки, размножение микроорганизмо

Study of synthesis of hydroxyapatite using phosphogypsum waste

The production of phosphoric acid generates phosphorus gypsum waste. It is imposible to avoid this by-product therefore, there is a constant search for ways to use phosphogypsum. A new area of application for phosphogypsum is the synthesis of hydroxyapatite from phosphogypsum waste (Pewkeaw et al., 2018). Technically pure hydroxyapatite can be used in medicine. Currently a lot of studies are examining the adsorption properties of hydroxyapatite. Hydroxyapatite can be used in the production of wastewater treatment filters because of its high adsorption of fluorine, metals and paint residues. Other applications of phosphogypsum are analyzed, however this synthesis is similar, because by-product is utilized to produce material that can be used for waste water treatment. In this experiment, hydroxyapatite was synthesized by changing the synthesis conditions, and 8 samples were synthesized to select the optimal synthesis conditions. After synthesis the physical properties (moisture content, pH of the samples after synthesis) and chemical composition of the samples were evaluated. The most important indicator of the quality of hydroxyapatite is the ratio of calcium to phosphorus. This ratio should be the same as in human bone – 1,677 (7). The highest Ca/P ratio (1.68) was found for the sample obtained during the synthesis for 4 h without stirring at a pressure of 0.1 bar in a closed system. The content of heavy metals in the samples synthesized during the test does not exceed the norm of the hydroxyapatite quality standard

INVESTIGATION OF LIME STABILIZATION ON THE ORGANIC WASTE BIODEGRADATION PRODUCTS

The growth of pig industry has caused a great release of organic waste to the environment. Therefore, it can cause excessof nutrients in agriculture, eutrophication of surrounding surface water, hospitable environment for pathogen release and great problemof offensive odours.It was studied the possibility of using lime production-related waste, animal waste management. Management techniques are saferand meet environmental requirements. Organic waste odors caused by neutralization was assessed by inserting different lime levels(15%, 20% and 25% lime). Experimental studies have shown that lime be used as a conducting additive odor prevention and wastetranslates useful agricultural fertilizer.KEY WORDS: odours, lime stabilization, ammonia, hydrogen sulfide, acetic acid, mercaptans

Naftos produktų biodegradacinis aktyvumas dirvožemyje

The current study is aimed to determine how sewage sludge may impact the biodegradation activity of soil contaminated with oil products and what groups of microorganisms are most active in it. Bathihypogleyi-Dystric Albeluvisol (ABd-gld-w) with a texture of sandy loam was selected for laboratory tests. The soil was contaminated with heavy fuel oil 15 and 30 g kg-1, supplemented with sewage sludge to create three backgrounds: 1) without sludge, 2) 5% (50 g kg-1) and 3) 10% (100 g kg-1) of sludge for air-dried soil. The trend was determined that when treating soil contaminated with heavy fuel oil the highest treatment efficiency was achieved by supplementing the soil with 10% of activated sewage sludge. Microorganisms which take part in the process of biodegradation of heavy fuel oil demonstrated different levels of activity during the investigation period. Hydrocarbon-oxidizing bacteria and micromycetes are the most important groups of microorganisms involved in the degradation of heavy fuel oil products in the soil. The initial concentration of heavy fuel oil in the soil had no statistically significant differences for all analyzed groups of microorganisms, although the number of bacteria and micromycetes, capable of oxidizing oil products, was statistically significantly influenced by the degradation time. The increasing concentration of sewage sludge statistically significantly affected the total number of bacteria and actinobacteria

Naftos produktų biodegradacinis aktyvumas dirvožemyje

The current study is aimed to determine how sewage sludge may impact the biodegradation activity of soil contaminated with oil products and what groups of microorganisms are most active in it. Bathihypogleyi-Dystric Albeluvisol (ABd-gld-w) with a texture of sandy loam was selected for laboratory tests. The soil was contaminated with heavy fuel oil 15 and 30 g kg-1, supplemented with sewage sludge to create three backgrounds: 1) without sludge, 2) 5% (50 g kg-1) and 3) 10% (100 g kg-1) of sludge for air-dried soil. The trend was determined that when treating soil contaminated with heavy fuel oil the highest treatment efficiency was achieved by supplementing the soil with 10% of activated sewage sludge. Microorganisms which take part in the process of biodegradation of heavy fuel oil demonstrated different levels of activity during the investigation period. Hydrocarbon-oxidizing bacteria and micromycetes are the most important groups of microorganisms involved in the degradation of heavy fuel oil products in the soil. The initial concentration of heavy fuel oil in the soil had no statistically significant differences for all analyzed groups of microorganisms, although the number of bacteria and micromycetes, capable of oxidizing oil products, was statistically significantly influenced by the degradation time. The increasing concentration of sewage sludge statistically significantly affected the total number of bacteria and actinobacteria

Electrochemical processes occurring during pulsed electric field treatment and their consequences

Electroporation is an effective method for the modification of the cell membrane permeability with an increasing number of applications in biology, oncology, genetics, immunology, and biotechnology. When using high-voltage electrical pulses for treatment of cells and tissues, scientists must keep in mind that the products generated due to electrochemical reactions can influence various processes taking part in their experimental systems. Due to this, the efficiency of electroporation technique depends not only on the parameters of electric treatment but on the electrochemical processes as well. The primary anodic and cathodic electrochemical reactions and secondary processes that can take place during the treatment by high-voltage electrical pulses used in electroporation experiments are reviewed. These include pH changes (acidification around the anode and alkalinisation at the cathode), the production of H2, O2, and Cl2 gases, and the release of the metal ions from the electrodes. Consequences of these reactions which may be important for optimization of cell electromanipulation procedures, such as arcing, the complexation of the metal ions released from the electrodes with the molecules present in the solution, quenching of fluorescence of fluorescent dyes, reduction of the cell viability, the increase of the roughness of the electrode surface due to the dissolution of the electrode material, and other ones are discussedBiologijos katedraRegionistikos katedraVytauto Didžiojo universiteta