39 research outputs found
Thermodynamic analysis of an industrial process integration of a reversed Brayton high-temperature heat pump: A case study of an industrial food process
Industry, as a major emitter of CO2 in the process heat sector in Europe, needs to switch from fossil fuels to renewable energy for heat supply. High temperature heat pumps (HTHP) can electrify process heat and integrate renewable electricity into industrial processes. The Institute of Low-Carbon Industrial Processes of the German Aerospace Center (DLR) is developing HTHPs based on the reversed Brayton and Rankine cycles for delivery temperatures above 150°C and is investigating the industrial process integration of this novel technology. The current study considers different integration strategies of a reversed Brayton HTHP in a food production process with a heat sink at 250 °C. A thermodynamic analysis evaluates the results. This study allows conclusions to be drawn about the process integration of Brayton HTHPs in industrial food processes or other industrial processes with heat sinks around 250 °C
Investigation on Process Architectures for High-Temperature Heat Pumps Based on a Reversed Brayton Cycle
Heat pumps are a core technology for the decarbonization
of industrial process heat. High-temperature heat pumps
(HTHP) typically upgrade waste heat of industrial processes.
This way they can simultaneously electrify process heat and
reduce the respective primary energy consumption. The
utilization of renewable electricity to drive HTHP additionally
results in decarbonization of process heat supply. Commercial
industrial heat pumps supply process heat at temperatures up to
approximately 150°C. However, several studies have shown that
process heat can be also supplied with HTHP at temperatures
above 150°C. The economic and environmental performance of
HTHPs depend strongly on their process architecture and their
integration into the industrial process they supply with heat. This
paper focuses on the investigation of high-temperature heat
pump process architectures based on the reversed Brayton cycle
with air as the working medium. The process architecture of the
HTHP pilot plant at the Institute of Low-Carbon Industrial
Processes of the German Aerospace Center (DLR) is presented
and used as a reference. The current work investigates the heat
source and heat sink integration in the heat pump cycle
architecture and methods to effectively break down the
compression and expansion processes to optimize performance
for a heat sink temperature of 250°C. To analyze and compare
the results, fixed boundary conditions valid for all architectures
are made
Thermodynamic analysis of an industrial process integration of a reversed Brayton high-temperature heat pump: A case study of an industrial food process
Industry, as a major emitter of CO2 in the process heat sector in Europe, needs to switch from fossil fuels to renewable energy for heat supply. High temperature heat pumps (HTHP) can electrify process heat and integrate renewable electricity into industrial processes. The Institute of Low-Carbon Industrial Processes of the German Aerospace Center (DLR) is developing HTHPs based on the reversed Brayton and Rankine cycles for delivery temperatures above 150°C and is investigating the industrial process integration of this novel technology. The current study considers different integration strategies of a reversed Brayton HTHP in a food production process with a heat sink at 250 °C. A thermodynamic analysis evaluates the results. This study allows conclusions to be drawn about the process integration of Brayton HTHPs in industrial food processes or other industrial processes with heat sinks around 250 °C
Mindfulness-Based Childbirth and Parenting Education: Promoting Family Mindfulness During the Perinatal Period
We present the conceptual and empirical foundation and curriculum content of the Mindfulness-Based Childbirth and Parenting (MBCP) program and the results of a pilot study of n = 27 pregnant women participating in MBCP during their third trimester of pregnancy. MBCP is a formal adaptation of the Mindfulness-Based Stress Reduction program and was developed and refined over the course of 11 years of clinical practice with 59 groups of expectant couples. MBCP is designed to promote family health and well-being through the practice of mindfulness during pregnancy, childbirth, and early parenting. Quantitative results from the current study include statistically significant increases in mindfulness and positive affect, and decreases in pregnancy anxiety, depression, and negative affect from pre- to post-test (p < .05). Effect sizes for changes in key hypothesized intervention mediators were large (d > .70), suggesting that MBCP is achieving its intended effects on maternal well-being during pregnancy. Qualitative reports from participants expand upon the quantitative findings, with the majority of participants reporting perceived benefits of using mindfulness practices during the perinatal period and early parenting. Our future research will involve conducting a randomized controlled trial of MBCP to test effects on psychophysiological stress mechanisms and to examine effects on birth outcomes, family relationship quality, and child development outcomes
Developmental pathway for potent V1V2-directed HIV-neutralizing antibodies.
CAPRISA, 2014.Antibodies capable of neutralizing HIV-1 often target variable regions 1 and 2 (V1V2) of the HIV-1 envelope, but the mechanism of their elicitation has been unclear. Here we define the developmental pathway by which such antibodies are generated and acquire the requisite molecular characteristics for neutralization. Twelve somatically related neutralizing antibodies (CAP256-VRC26.01-12) were isolated from donor CAP256 (from the Centre for the AIDS Programme of Research in South Africa (CAPRISA)); each antibody contained the protruding tyrosine-sulphated, anionic antigen-binding loop (complementarity-determining region (CDR) H3) characteristic of this category of antibodies. Their unmutated ancestor emerged between weeks 30-38 post-infection with a 35-residue CDR H3, and neutralized the virus that superinfected this individual 15 weeks after initial infection. Improved neutralization breadth and potency occurred by week 59 with modest affinity maturation, and was preceded by extensive diversification of the virus population. HIV-1 V1V2-directed neutralizing antibodies can thus develop relatively rapidly through initial selection of B cells with a long CDR H3, and limited subsequent somatic hypermutation. These data provide important insights relevant to HIV-1 vaccine development
Numerical study of the part load operation for a reverse Brayton high-temperature heat pump
Electrification of industrial process heat from renewable sources can contribute to the reduction of energy-related CO2 emissions. High-temperature heat pumps are one of the most important technologies to realize this electrification while reducing the electrical energy required for it. The Institute of Low-Carbon Industrial Processes of the German Aerospace Center (DLR) is developing high-temperature heat pumps (HTHP) based on reverse Brayton and Rankine cycles for heat transfer temperatures above 150 °C. The development and integration process of HTHPs for industrial processes often starts with their sizing at nominal operating conditions. Once the operational boundary conditions are defined, the individual components are sized. A large proportion of industrial heat pumps operate at a fixed point and are not optimized or designed for frequent part-load operation. This is expected to change, especially when heat pumps are required for industrial processes with part load operation. The current work presents an analysis of the part load operation of a reverse Brayton HTHP built in the laboratory of DLR and investigates its operational limits
Thermodynamic analysis of an industrial process integration of a reversed Brayton high-temperature heat pump: A case study of an industrial food process
Industry, as a major emitter of CO2 in the process heat sector in Europe, needs to switch from fossil fuels to renewable energy for heat supply. High temperature heat pumps (HTHP) can electrify process heat and integrate renewable electricity into industrial processes. The Institute of Low-Carbon Industrial Processes of the German Aerospace Center (DLR) is developing HTHPs based on the reversed Brayton and Rankine cycles for delivery temperatures above 150°C and is investigating the industrial process integration of this novel technology. The current study considers different integration strategies of a reversed Brayton HTHP in a food production process with a heat sink at 250 °C. A thermodynamic analysis evaluates the results. This study allows conclusions to be drawn about the process integration of Brayton HTHPs in industrial food processes or other industrial processes with heat sinks around 250 °C