Adaptive set-point control system for microbial cultivation processes

A control system for set-point control of microbial cultivation process parameters is developed, in which a tendency model is applied for controller adaptation to process nonlinearity and time-varying operating conditions. The tendency model is updated on-line and introduced into control algorithm for prediction of steady-state control action and returning of feedback controller. The control system was tested for controlling dissolved oxygen concentration in batch operating mode bioreactor under extreme operating conditions. In simulation experiments, the control system demonstrates fast adaptation, robust behaviour and significant improvement in control performance compared to that of fixed gain controller

Technology for treatment of lipid-rich wastewater and pipelines clogged by lipids using bacterial preparation

The complex, effective and innovative cleaning technology for lipid-rich wastewater and pipelines contaminated by lipids, was developed. For this purpose, laboratory experiments were performed to verify the efficiency of bacterial preparation (Enterobacter aerogenes E13, Arthrobacter sp. N3 and Bacillus coagulans S1) to degrade the grease in water and in drainpipes. The results showed that selected microorganisms intensively degrade grease to light odourless precipitate, water and CO2, thus could be applied in industry. For optimization of technological cleaning processes, the response surface methodology was used. The optimal parameters for biological model wastewater treatment were determined: concentration of grease − 4.5–6.0 g/l, amount of bacterial preparation −5.5–6.0%, pH – 8–9. Due to optimization, the grease degradation rate increased by 20–30%. The optimization of drainpipe cleaning technology was achieved in two stages. During the first stage, the experiments were performed in laboratory flasks; during the second stage, optimized cleaning process was tested in a pilot plant. The following optimal parameters were set: pH – 8, amount of bacterial preparation –1.25 l/m2 and harness of water – 0.0 mmol/l. In water of medium hardness, the rate of biodegradation process is 15–20% less. A satisfactory efficiency of grease biodegradation was achieved in the pilot plant: the 86.7% of grease were digested in 21 days. Besides, living microorganisms were detected inside the clean drainpipe. Santrauka Sukurta kompleksinė, efektyvi ir inovacinė nuotekų bei vamzdynų, užterštų riebalais, valymo technologija. Atlikti laboratoriniai eksperimentai, siekiant nustatyti biopreparato, sudaryto iš Enterobacter aerogenes E13, Arthrobacter sp. N3 ir Bacillus coagulans S1, riebalų skaidymo efektyvumą kiek vandenyje, tiek vamzdyje. Gauti rezultatai parodė, kad atrinkti mikroorganizmai intensyviai skaido riebalus iki lengvų, neturinčių nemalonaus kvapo nuosėdų, vandens ir CO2, todėl gali būti taikomi pramonėje. Technologiniam valymo procesui optimizuoti taikyta reakcijos paviršiaus metodologija. Nustatyti optimalūs nuotekų, užterštų riebalais, valymo technologiniai parametrai: riebalų koncentracija – 4,5–6,0 g/l, biopreparato kiekis – 5,5–6,0%, pH – 8–9. Optimizavus procesą, riebalų skaidymo greitis padidėja 20–30 %. Vamzdžių, užterštų riebalais, valymo technologijos optimizavimas atliktas dviem etapais. Pirmajame etape eksperimentiniai tyrimai atlikti kolbose, antrajame etape optimizuotas procesas testuotas valant riebalinius teršalus bandomajame įrenginyje. Nustatyti optimalūs valymo parametrai: pH – 9, biopreparato kiekis – 1,25 l/m2 ir vandens kietis – 0,0 mmol/l. Esant vidutiniam vandens kiečiui biodagradacijos proceso greitis sumažėja 15–20%. Geras riebalų skaidymo efektyvumas pasiektas bandomajame įrenginyje, po 21 paros suskaidyta 86,7 % riebalų. Taip pat ant švaraus vamzdžio sienelių rasta gyvų mikroorganizmų. Резюме Создана комплексная, эффективная и инновационная технология очистки сточных вод и трубопроводов, загрязнённых липидами. С целью проверки эффективности бактериального состава (Enterobacter aerogenes E13, Arthrobacter sp. N3 и Bacillus coagulans S1) для расщепления жиров в воде и водосточной трубе были выполненылабораторные эксперименты. Полученные результаты показали, что отобранные микроорганизмы интенсивнорасщепляют жир до лёгкого осадка без побочного запаха воды и CO2 и могут быть применены в промышленности. Для оптимизации технологических процессов очистки использовался метод математического моделирования.Были определены оптимальные параметры для биологической обработки сточных вод: концентрация жира – 4,5– 6,0 г/л, количество бактериального состава – 5,5–6,0%, pH фактор – 8–9. После оптимизации скорость деградации жира увеличилась на 20–30%. Оптимизация технологии по очистке водосточных труб была выполнена на двухстадиях. На первой стадии эксперименты были выполнены в лабораторных колбах. На второй стадии оптимизационный процесс очистки был проведен в пилотной установке. Были установлены оптимальные параметры: pH фактор – 8, количество бактериального состава – 1,25 л/м2 и жёсткость воды – 0,0 ммол/л. В среднежёсткой водескорость процесса биологического распада была на 15–20% меньше. Хорошая биодеградация жира была установлена в пилотной установке. 86,7% жира было расщеплено за 21 день. Также в чистой водосточной трубе были обнаружены живые микроорганизмы. Reikšminiai žodžiai: lipidai, riebalai, nuotekos, biopreparatas, biodegradacija, matematinis modelis, optimizavimas Ключевые слова: липиды, жиры, сточные воды, бактериальный состав, биодеградация, математическое моделирование, оптимизаци

Development of fatty waste composting technology using bacterial preparation with lipolytic activity

A new composting technology of waste with high fat content was developed in JSC “Biocentras”. The composting technology of fat‐contaminated waste is based on the use of fat‐oxidizing microorganisms. Developed technology is commended for cleaner production/pollution prevention approach as well as meets strict environmental and hygiene requirements. The composting process was investigated for the process optimization by applying the response surface methodology. Values of parameters of composting process were monitored in lab‐scale composters. The optimal composition of the composing mixture was determined: the initial fat content – 5%, the concentration of bacterial preparation cells – 109 CFU/g, the quantity of structural materials – 9.5%. Fat degradation rate slowed down 3 times if the initial fatty concentration increased from 5% to 20%. Concentrated fatty‐waste disposal site prototype was designed. Composting process duration lasted 1 to 1.5 year. Santrauka UAB “Biocentre” sukurta nauja riebalais užterštu atlieku kompostavimo technologija, pagrista riebalus oksiduojančiu mikroorganizmu panaudojimu. Ši technologija pažangesne taršos prevencijos požiūriu, jos privalumas – švaresne gamyba. Sukurtoji technologija atitinka griežtus aplinkos apsaugos ir higienos reikalavimus. Tyrimai atlikti laboratorinemis salygomis. Riebaliniu atlieku kompostavimo procesu technologiniams parametrams optimizuoti taikyta faktoriniais eksperimentais grista reakcijos paviršiaus analizes metodologija. Nustatyta optimali eksperimentine kompostuojamo mišinio sudetis: pradinis riebalu kiekis – 5 %, biopreparato lasteliu koncentracija – 109 KSV/g, struktūrines medžiagos kiekis – 9,5 %. Padidinus pradine riebalu koncentracija nuo 5 % iki 20 %, riebalu skaidymo sparta suleteja apie 3 kartus. Suprojektuotas koncentruotu riebaliniu atlieku utilizavimo aikšteles modelis. Kompostavimo proceso trukme 1–1,5 metu. Резюме В ЗАО “Biocentras” была создана новая технология компостирования отходов с высоким содержанием жира. Технология компостирования загрязненных жирами отходов основана на использовании микроорганизмов, окисляющих жиросодержащие вещества. Разработанная технология является привлекательной для более чистого производства/предупреждения загрязнения окружающей среды, а также удовлетворяет строгим экологическим и гигиеническим требованиям. Исследован процесс компостирования. Для оптимизации процесса применен метод математического моделирования. Опыты проведены в лабораторных условиях. Определен оптимальный состав смеси: начальное содержание жира – 5%, концентрация бактериальных клеток в препарате – 109 КОЕ/г, количество структурных материалов – 9,5%. Деградация жиров замедляется в 3 раза, если первоначальная концентрация жиров увеличивается от 5% до 20%. Разработан и построен прототип площадки для компостирования жировых отходов. Процесс компостирования длится от 1 до 1,5 лет. First Publish Online: 10 Feb 2011 Reikšminiai žodžiai: taukai, aliejus ir lajus, kompostavimas, biopreparatas, biodegradacija, matematinis modeliavimas, optimizacija. Ключевые слова: жиры, растительные и животные масла, компостирование, бактериальный препарат, биоразложение, математическое моделирование, оптимизация

Design and applications of a neural networks assisted portable liquid surface tensiometer

In this paper, a portable instrument for surface tension measurements, characterization and applications is described. The instrumentation is operated wirelessly, and samples can be measured in situ. The instrument has changeable different size probes; therefore, it is possible to measure samples from 1 ml up to 10 ml. The response of the measured retraction force and the concentrations of measured surfactant is complex. Therefore, two calibration methods were proposed: (i) the conditional calibration using polynomial and logarithmic fitting and (ii) the neural network trained model prediction of the surfactant concentration in samples. Calibrating the instrument, the neural network trained model showed a superior coefficient of determination (0.999), comparing it to the conditional calibration using polynomial (0.992) and logarithmic (0.991) fit equations

Simple Gain-Scheduled Control System for Dissolved Oxygen Control in Bioreactors

An adaptive control system for the set-point control and disturbance rejection of biotechnological-process parameters is presented. The gain scheduling of PID (PI) controller parameters is based on only controller input/output signals and does not require additional measurement of process variables for controller-parameter adaptation. Realization of the proposed system does not depend on the instrumentation-level of the bioreactor and is, therefore, attractive for practical application. A simple gain-scheduling algorithm is developed, using tendency models of the controlled process. Dissolved oxygen concentration was controlled using the developed control system. The biotechnological process was simulated in fed-batch operating mode, under extreme operating conditions (the oxygen uptake-rate’s rapidly and widely varying, feeding and aeration rate disturbances). In the simulation experiments, the gain-scheduled controller demonstrated robust behavior and outperformed the compared conventional PI controller with fixed parameters

The optimization of biodiesel fuel production from microalgae oil using response surface methodology

Biodiesel fuel was produced by the transesterification of microalgae oil using sodium hydroxide as a catalyst. The oil was extracted from heterotrophic cultivated algae biomass. The transesterification process was optimized using response surface methodologyto increase the yield of methyl esters. The Box–Behnken design and fractional factorial design 24-1 points were used to investigate the interaction of process variables, such as the methanol/oil molar ratio, the percentage of sodium hydroxide, the temperature, and the reaction time in the production of biodiesel fuel, and to predict the optimum process conditions for the FAME yield. Based on the results, the optimal conditions for the synthesis of biodiesel fuel were as follows: methanol/oil molar ratio, 7:1; catalyst concentration, 1.0% (by weight of algae oil); temperature, 67◦C, and reaction time, 51 minutes. The yield of FAME was confirmed by gas chromatography analysisVytauto Didžiojo universitetasŽemės ūkio akademij

Riebalinių atliekų kompostavimo technologijos sukūrimas naudojant lipazinio aktyvumo bakterinį preparatą

A new composting technology of waste with high fat content was developed in JSC „Biocentras”. The compos-ting technology of fat-contaminated waste is based on the use of fat-oxidizing microorganisms. Developed technology is commended for cleaner production/pollution prevention approach as well as meets strict environmental and hygiene requirements. The composting process was investigated for the process optimization by applying the response surface me-thodology. Values of parameters of composting process were monitored in lab-scale composters. The optimal composition of the composing mixture was determined: the initial fat content – 5%, the concentration of bacterial preparation cells – 109 CFU/g, the quantity of structural materials – 9.5%. Fat degradation rate slowed down 3 times if the initial fatty con-centration increased from 5% to 20%. Concentrated fatty-waste disposal site prototype was designed. Composting process duration lasted 1 to 1.5 year.Lietuviška santrauka. UAB „Biocentre“ sukurta nauja riebalais užterštų atliekų kompostavimo technologija, pagrįsta riebalus oksiduojančių mikroorganizmų panaudojimu. Ši technologija pažangesnė taršos prevencijos požiūriu, jos privalumas – švaresnė gamyba. Sukurtoji technologija atitinka griežtus aplinkos apsaugos ir higienos reikalavimus. Tyrimai atlikti laboratorinėmis sąlygomis. Riebalinių atliekų kompostavimo procesų technologiniams parametrams optimizuoti taikyta faktoriniais eksperimentais grįsta reakcijos paviršiaus analizės metodologija. Nustatyta optimali eksperimentinė kompostuojamo mišinio sudėtis: pradinis riebalų kiekis – 5 %, biopreparato ląstelių koncentracija – 109 KSV/g, struktūrinės medžiagos kiekis – 9,5 %. Padidinus pradinę riebalų koncentraciją nuo 5 % iki 20 %, riebalų skaidymo sparta sulėtėja apie 3 kartus. Suprojektuotas koncentruotų riebalinių atliekų utilizavimo aikštelės modelis. Kompostavimo proceso trukmė 1–1,5 metų

Review of creosote pollution toxicity and possibilities of bioremediation

BiocentrasBiochemijos katedraJSC Biocentras, PagiriaiKauno technologijos universitetasVilniaus universitetasVytauto Didžiojo universiteta