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Techno-economic comparison of membrane distillation and MVC in a zero liquid discharge application
(2018)
Membrane distillation (MD) is a thermally driven membrane process for the separation of vapour from a liquid stream through a hydrophobic, microporous membrane. However, a commercial breakthrough on a large scale has not been achieved so far. Specific developments on MD technology are required to adapt the technology for applications in which its properties can potentially outshine state of the art technologies such as standard evaporation. In order to drive these developments in a focused manner, firstly it must be shown that MD can be economically attractive in comparison to state of the art systems. Thus, this work presents a technological design and economic analysis for AGMD and v-AGMD for application in a zero liquid discharge (ZLD) process chain and compares it to the costs of mechanical vapour compression (MVC) for the same application. The results show that MD can potentially be ~40% more cost effective than MVC for a system capacity of 100 m3/day feed water, and up to ~75% more cost effective if the MD is driven with free waste heat.
Marketing-Automation-Systeme
(2018)
Einleitung
(2018)
Social Media Controlling
(2018)
Markenbewertung
(2018)
Erfolgsfaktorenforschung
(2018)
Kundenbindungscontrolling
(2018)
Photovoltaics Energy Prediction Under Complex Conditions for a Predictive Energy Management System
(2015)
An energy oriented design concept was developed within the research project PHOTOPUR which has the development of a PV powered water cleaning system as main focus. During a wine season Plant Protection Products (PPP) are several times sprayed on plants to protect them of undesired insects and herbs or avoid hazardous fungus
types. A work package of the project partner INES in Offenburg led to a design introducing energy profiling already in the early beginning of a product design. The concept is based on three pillars respecting first the
requirements of the core process making up filtering and cleaning and secondary aspects which run, support, maintain and monitor the system to secure availability and product reliability.
The presented paper shows that the results of the design tools guided the developers to assemble a functional model of the water decontamination unit which was manually tested with its concatenated steps of the water cleaning process.
Sustainable Aspects force a building manager to continuous observation of actual states and developments concerning building use, energy and media flows.In the presented approach a communication structure was built up to use different software applications and tools in order to optimize the operation of the building.
Intelligent und nachhaltig
(2013)
Cardiac contractility modulation (CCM) is a
device-
based therapy for the treatment of systolic left
ventricular chronic heart failure. Unlike other device
-
based therapies for heart failure, CCM delivers non
-
excitatory pacing signals to the myocardium. This leads to
an extension of the action potential and to an improved
contractility of the heart. The modeling and simulation
was done with the electromagnetic simulation software
CST. Three CCM electrodes were inserted into the
Offenburg heart rhythm model an
d subsequently
simulated the electric field propagation in CCM therapy.
In addition, simulations of CCM have been performed
with electrodes from other device
-based therapies, such as
cardiac resynchronization therapy (CRT) and implantable
cardioverter.
/. defi
brillator (ICD) therapy.
At the same
distance to the simulation electrode, the electric field is
slightly stronger in CCM therapy than in CCM therapy
with additionally implanted CRT or ICD electrodes. In
addition, there is a change in the electric field pr
opagation
at the electrodes of the CRT and the shock electrode of the
ICD.
By simulating several different therapy procedures
on the heart, it is possible to check how they affect their
behavior during normal operation. CCM heart rhythm
model simulation al
lows the evaluation the individual
electrical pacing and sensing field during CCM.
Abstract: Electric field of biventricular (BV) pacing, left ventricular (LV) electrode position and electrical interventricular desynchronization are important parameters for successful cardiac resynchronization therapy (CRT) in patients with heart failure, sinus rhythm and reduced LV ejection fraction. The aim of the study was to evaluate electric pacing field of transesophageal left atrial (LA) pacing and BV pacing with 3D heart rhythm simulation. Bipolar right atrial (RA), right ventricular (RV), LV electrodes and multipolar hemispherical esophageal LA electrodes were modeled with CST (Computer Simulation Technology, Darmstadt). Electric pacing field were simulated with bipolar RA and RV pacing with Solid S (Biotronik) electrode, bipolar LV pacing with Attain 4194 (Medtronic) electrode and bipolar LA pacing with TO8 (Osypka) esophageal electrode. 3D heart rhythm model with esophagus allowed electric pacing field simulation of 4-chamber pacing with bipolar intracardiac RA, RV, LV pacing and bipolar transesophageal LA pacing. The pacing amplitudes were 3V RA pacing amplitude, 50V LA pacing amplitude, 1.5V RV pacing amplitude and 3V LV pacing amplitude with 0.5ms pacing pulse duration. The atrioventricular delay between RA pacing and BV pacing was 140ms atrioventricular pacing delay and simultaneous RV and LV pacing. Electric pacing fields were simulated during the different pacing modes AAI, VVI, DDD and DDD0V. The intracardiac far-field pacing potentials were evaluated with intracardiac electrodes and a distance of 1mm from the electrodes with RA electrode 1.104V, RV electrode 0.703V and LV electrode 1.32V. The transesophageal far-field pacing potential was evaluated with transesophageal electrode and a distance of 10mm from the elelctrode with LA electrode 6.076V. Heart rhythm model simulation with esophagus allows evaluation of electric pacing fields in AAI, VVI, DDD, DDD0V and DDD0D pacing modes. Electric pacing field of RA, RV and LV pacing in combination with LA pacing may additional useful pacing mode in CRT non-responders.
Pulmonary vein isolation (PVI) is a common
therapy in atrial fibrillation (AF). The cryoballoon was
invented to isolate the pulmonary vein in one step and in a
shorter time than a point-by-point radiofrequency (RF)
ablation. The aim of the study was to model two cryoballoon
catheters, one RF catheter and to integrate them into a heart
rhythm model for the static and dynamic simulation of PVI
by cryoablation and RF ablation in AF. The modeling and
simulation were carried out using the electromagnetic and
thermal simulation software CST (CST, Darmstadt). Two
cryoballons and one RF ablation catheter were modeled
based on the technical manuals of the manufacturers
Medtronic and Osypka. The PVI especially the isolation of
the left inferior pulmonary vein using a cryoballoon catheter
was performed with a -50 °C heatsource and an exponential
signal. The temperature at the balloon surface was -50 °C
after 20 s ablation time, -24 °C from the balloon 0,5 mm in
the myocardium, at a distance of 1 mm -3 °C, at 2 mm 18 °C
and at a distance of 3mm 29 °C. PVI with RF energy was
simulated with an applied power of 5 W at 420 kHz at the
distal 8 mm ablation electrode. The temperature at the tip
electrode was 110 °C after 15 s ablation time, 75 °C from the
balloon at 0,5 mm in the myocardium, at a distance of 1 mm
58 °C, at 2 mm 45 °C and at a distance of 3 mm 38 °C.
Virtual heart rhythm and catheter models as well as the
simulation of the temperature allow the simulation of PVI in
AF by cryo ablation and RF ablation. The 3D simulation of
the temperature profile may be used to optimize RF and cryo
ablation.
The high frequency (HF) catheter ablation is the gold standard for the therapy of many cardiac tachyarrhythmias, such as atrioventricular node re-entry tachycardia (AVNRT), atrioventricular re-entry tachycardia (AVRT) or atrial flutter (AFL). The aim of the study was to simulate the HF ablation of AVNRT, AVRT, AFL and its heat propagation in reference to the supplied power with different electrode material and electrode size. The modeling and simulation were performed with the thermal and electromagnetic simulation software CST® (Computer Simulation Technology, Darmstadt). The modeling and simulation were carried out using ablation catheters with 4 mm tip electrode and 8 mm tip electrode with different electrode materials. Both electrode types were made of platinum and gold respectively. For the measurement of the heat propagation in the heart tissue, the catheters were integrated in the Offenburg heart rhythm model. The HF ablation procedures were performed with the 4 mm platinum tip electrode, with an application duration of 45 seconds and a power output of 40 watts. The HF ablation of the atrioventricular node slow pathway produced a maximum temperature of 66.33 °C. The Kent bundle HF ablation in the left atrium achieved a maximum temperature of 67.14 °C. The HF ablation of the right atrial isthmus resulted 65.96 °C. The 8 mm distal platinum tip electrode and a power output of 60 watts reached 72.85 °C. The 8 mm distal gold tip electrode and a power output of 60 watt reached 64.66 °C, due to the improved thermal conductivity of gold. Virtual heart and ablation electrode models allow the static and dynamic simulation of HF ablation with different electrode material and electrode size. The 3D simulation of the temperature profile may be used to optimize the AVNRT, AVRT and AFL HF ablation.
Die starke Nachfrage für wirtschaftliche und technische Lösungen zur Umsetzung der Energiewende wirkt sich auch auf Projektinitiativen der Forschungsgruppen am Institut für Energiesystemtechnik (INES) der Hochschule Offenburg aus. Am Campus Nord entsteht seit 2012 ein intelligentes Energienetz als Reallabor, das als Teil eines Smart Grid betrieben werden kann.