Bubble Point Temperature Research Articles

Numerical investigation in effects of refrigerants’ thermodynamic properties on performance of supersonic ejector

ABSTRACT Using zeotropic mixtures with unique temperature glide characteristics as the working medium in heat-driven ejector refrigeration system will potentially reduce the irreversible losses in heat exchange process. However, the intrinsic link between the pure/mixture refrigerants’ thermophysical properties and the entrainment performance of supersonic ejector has not yet been elucidated. In this study, a novel ejector CFD model is established by coupling the real-gas thermodynamic equation and species transport equation, then the relationships between thermophysical properties of pure/mixture refrigerants and ejector’s dimensionless operational parameters were thoroughly investigated. The results indicated that the ejector expansion ratio rises as primary flow inlet temperature or refrigerant’s normal boiling point increases, while the dimensionless parameters of primary nozzle are relatively insensitive to the variation of primary flow inlet temperature and refrigerant’s boiling point, resulted in changes of supersonic jet expansion behaviour. Moreover, the specific volume and adiabatic index change characteristics resulted in minor fluctuations of primary nozzle’s dimensionless parameters. When the bubble point temperature is fixed at 30℃ in the condenser, the saturated vapor/liquid phase pressure glide characteristics of R600a/R1234ze mixture may lead to an increasement of ejector’s compression ratio.

Isochoric bubble point data for binary systems of 1 (ethane) in 2 (decane, undecane, dodecane and tridecane)

In this communication, a new set of vapour liquid equilibrium (bubble point) data were obtained for ethane-decane, ethane-undecane, ethane-dodecane and ethane-tridecane binary systems. The datasets were obtained using constant-volume (isochoric) method. The datasets cover temperatures from 260 to 373 K and pressures from 0.6 to 10 MPa for all binary systems. A total of five compositions were studied for each of the binary systems ranging from ethane rich compositions to compositions rich in decane, undecane, dodecane and tridecane respectively. Datasets obtained were used to adjust the binary interaction parameters (BIP) for Peng-Robinson (PR), Perturbed Chain Statistical Associating Fluid Theory (PC-SAFT) and the Multi-Fluid Helmholtz Energy Approximation (MFHEA) equations of state (EoS). Quadratic temperature dependent BIP functions were obtained for PR-EoS using a combination of datasets from this work and those published in the literature for the ethane-decane and ethane-dodecane binary systems. Correlation of the datapoints from this work with the PR-EoS, PC-SAFT-EoS and MFHEA EoS yielded very low average absolute deviations (AADs) of less than 5 % for all the datasets. Expanded uncertainties associated with each of the bubble point temperatures and pressures obtained are also reported at 95 % confidence interval. Expanded uncertainties in all the compositions studied were found to be less than 0.002 at 95 % confidence interval.

Correlations between Petroleum Reservoir Fluid Properties and Amount of Evolved and Dissolved Natural Gas: Case Study of Transgressive–Regressive-Sequence Sedimentary Rocks

It is well recognized that PVT data are essential in oil and gas production facilities as well as in the determination of the reservoir fluid composition in reservoir engineering calculations. In the current work, the studied borehole is located in Tawke oilfield in the High Folded Zone. The structural geology and lithological facies of rocks are studied and found to comprise fine crystalline dolomite and anhydrite interbedded with claystone and dolomite. In addition, the practical PVT data of black oil from Tawke oilfield, Zakho, from reservoirs to transgressive–regressive cycles, are studied. The PVT data are investigated to derive the empirical models that rule and correlate the properties of the reservoir fluids in terms of the amount of natural gas (methane, ethane, and propane) dissolved in reservoir fluids and evolving from the wells. The characteristics of the reservoir fluid, including °API, viscosity at reservoir pressure and bubble-point pressure, reservoir pressure and temperature, gas–oil ratio (GOR), coefficient of compressibility at reservoir pressure, gross heating value, and sample depth, are correlated. The lithological part reveals that the carbonate and some clastic rock facies are conducive to enhancing natural gas adsorption. The reservoir fluid properties show adverse effects on the amount of natural gas constituents evolving from the wells, while it shows positive effects on the dissolved reservoir fluids. The estimated empirical correlations can help indicate the quantity of natural gas that is dissolved in reservoir fluids and liberated from the wells depending on the characteristics of the reservoir. In addition, they can be used in numerical simulators to predict oil well performance.

Equation of State Associated with Activity Coefficient Model Based on Elements and Chemical Bonds

A new element- and chemical bond-dependent GE-EoS model(SRK-UNICAC) is proposed to consider the deviation of the vapor and liquid phases from the ideal state. The SRK-UNICAC model combines the UNICAC model and the SRK cubic equation of state. It uses the original interaction parameters of the UNICAC model and uses this model to calculate the GE. The SRK-UNICAC model predicted vapor-liquid equilibria for 87 binary systems under low- and medium-pressure conditions, 12 binary systems under high-pressure conditions, and 14 ternary systems; a comparison of the predictions with five other activity coefficient models were also made. The new model predicted the vapor-phase fraction and bubble-point pressure, and temperature for the binary system at high pressure, with a mean relative error of 3.75% and 6.58%, respectively. The mean relative errors of vapor-phase fraction and bubble-point temperature or bubble-point pressure for ternary vapor–liquid phase equilibrium were 6.50%, 4.76%, and 2.25%. The SRK-UNICAC model is more accurate in predicting the vapor–liquid phase equilibrium of high-pressure, non-polar, and polar mixtures and has a simpler and wider range of prediction processes. It can therefore be applied to the prediction of vapor–liquid equilibrium.

Study and application of the shift-temperature of heating fluid for zeotropic mixtures in organic Rankine cycle

The theoretical formulations of the shift-temperature of the heating fluid for zeotropic mixtures (Tshift) were derived when the pinch point was located at the evaporating bubble point and the working fluid inlet of the evaporator, respectively, which were applicable to dry, wet, and isentropic zeotropic mixtures. Tshift was corrected by the impact factor analysis and calculated exactly using the Dragonfly algorithm. The optimal zeotropic mixture was matched by comparing the heat source temperature(Tg, in) and Tshift. The results indicate that Tshift is a property of every zeotropic mixture and is related to the critical temperature, the evaporation bubble point temperature, and the condensation dew point temperature. When the pinch point is at the evaporation bubble point, the zeotropic mixture with Tshift lower than Tg, in is selected and then combined with the thermal efficiency for a comprehensive evaluation. When the pinch point is at the working fluid inlet of the evaporator, Tshift is also affected by the pinch point temperature difference and the temperature glide of the condensation process, Tshift is significantly lower than Tg, in, all zeotropic mixtures are applied. Among the matched zeotropic mixtures, R227ea/R22 with the lowest Tshift has the best thermal performance in the ORC system.

Numerical simulation of single bubble growth and heat transfer of R32+R1234yf binary mixtures during saturated pool boiling

As a promising alternative refrigerant for meeting carbon reduction targets, R32+R1234yf binary mixtures combine the thermal performance of R32 with the environmental performance of R1234yf. Since the degree of heat dissipation during the boiling process is closely related to bubble behavior, the bubble growth and heat transfer characteristics of R32+R1234yf mixtures must be understood in depth. Accordingly, this study proposed a numerical model for single bubble growth during nucleate pool boiling of mixtures. Numerical simulations of single bubble growth in R32, R1234yf, and four binary mixtures thereof were conducted. Owing to the preferential evaporation of the more volatile component, a low concentration region of R32 appeared in the liquid near the heating surface, while the concentration of R32 in the vapor was generally higher than that in the liquid. The evaporation heat flux at the bubble interface in the mixtures was significantly lower than in pure R32, indicating that the existence of mass transfer resistance considerably reduced the heat transfer capacity of mixtures. In contrast to a pure fluid, the microlayer evaporation in a mixture might terminate owing to an increase in the local bubble point temperature, and two modes of microlayer evaporation—called “bubble-point-controlled mode” and “thickness-controlled mode”—were identified accordingly. The total heat transferred during bubble growth first decreased and then increased with an increase in the bulk concentration of R32; a minimum value was observed at an R32 mol fraction of approximately 0.4. This result is consistent with the observed variation in the difference between the vapor and liquid phase concentrations. Overall, this study provides a detailed description of the mass and heat transfer characteristics during single bubble growth in binary mixtures, contributing to a deeper understanding of the associated boiling heat transfer mechanisms.

Thermal performance of a simplified parallel power and refrigeration combined cycle with refrigeration as the main task

• Simplified parallel power/refrigeration combined Kalina cycle was studied. • Obtaining larger refrigeration energy is the main purpose of the new combined cycle. • There is no desorption process of basic solution in the simplified cycle. • Simplified cycle was evaluated by efficiencies based on energy quality and quantity. • Simplified cycle can maintain high performance with much larger refrigeration capacity. A simplified parallel power and refrigeration combined cycle based on the Kalina cycle (SPPRA-KC) using ammonia-water as working fluid is proposed and studied, in which refrigeration is taken as the main task and the refrigerant plays a leading role in improving the concentration of work solution. The turbine exhaust vapor is utilized to heat the work solution fed to the refrigeration sub-cycle, resulting in more refrigeration energy produced. Parameter analysis was conducted under temperatures of heat source/cooling water of 400 °C/30 °C from the perspective of energy quantity and quality. To obtain larger refrigeration capacity and power recovery efficiency, the dew point temperature of work solution and bubble point temperature difference in the boiler shall be as higher as possible and properly increased, respectively, which will cause more irreversible losses in the cycle, resulting in lower effective exergy efficiency. When optimizing the cycles with work concentration of 0.5 based on the effective exergy efficiency, the power recovery efficiency of the SPPRA-KC is 34.8% much higher than that of the related original cycle (PPRA-KC) due to much larger refrigeration capacity, and the effective exergy efficiency of the SPPRA-KC is 1.67% and 12.4% relatively higher than those of the PPRA-KC and the Kalina cycle, respectively. Besides, the main exergy destruction of the SPPRA-KC occurs in the boiler, absorbers, exhaust heat source and turbine.

Simulation of the evaporation/boiling transition for the vaporization of a bi-component droplet under wide-temperature environments

A boiling model was proposed and coupled with a quasi-dimensional evaporation model to simulate the vaporization of a bi-component droplet under wide-temperature environments. Different from previous droplet evaporation models, the transition between droplet evaporation and boiling was especially focused on in this study. In the boiling model, the bubble point temperature of the bi-component mixture was employed to determine the critical condition for the occurrence of the boiling phenomenon. The mass rate of the boiling vaporization of the droplet was calculated by combining the heterogeneous nucleation model, bubble growth model, and bubble fragmentation model. Based on the measurements of the vaporization of an n-heptane/n-hexadecane droplet, the results indicate that the present vaporization model can satisfactorily reproduce the droplet lifetime and diameter evolution under wide ambient temperatures. The simulation results of the vaporization process are greatly affected by the boiling mass rate as the droplet enters the boiling stage. The heterogeneous nucleation rate is the main factor affecting the boiling mass rate, and the decrease of effective thermal conductivity slows down the overall droplet vaporization rate.

Thermo-economic investigation on the hydrogen production through the stored solar energy in a salinity gradient solar pond: A comparative study by employing APC and ORC with zeotropic mixture

In this paper, a salinity gradient solar pond (SGSP) is used to harness the solar energy for hydrogen production through two cycles. The first cycle includes an absorption power cycle (APC), a proton exchange membrane (PEM) electrolyzer, and a thermoelectric generator (TEG) unit; in the second one, an organic Rankine cycle (ORC) with the zeotropic mixture is used instead of APC. The cycles are analyzed through the thermoeconomic vantage point to discover the effect of key decision variables on the cycles’ performance. Finally, NSGA-II is used to optimize both cycles. The results indicate that employing ORC with zeotropic mixture leads to a better performance in comparison to utilizing APC. For the base mode, unit cost product (UCP), exergy, and energy efficiency when APC is employed are 59.9 $/GJ, 23.73%, and 3.84%, respectively. These amounts are 47.27 $/GJ, 29.48%, and 5.86% if ORC with the zeotropic mixture is utilized. The APC and ORC generators have the highest exergy destruction rate which is equal to 6.18 and 10.91 kW. In both cycles, the highest investment cost is related to the turbine and is 0.8275 $/h and 0.976 $/h for the first and second cycles, respectively. In the optimum state the energy efficiency, exergy efficiency, UCP, and H2 production rate of the system enhances 42.44%, 27.54%,15.95%, and 38.24% when ORC with the zeotropic mixture is used. The maximum H2 production is 0.47 kg/h, and is obtained when the mass fraction of R142b, LCZ temperature, pumps pressure ratio, generator bubble point temperature are 0.603, 364.35 K, 2.12, 337.67 K, respectively.

Study on approaches of extending refrigeration capacity range of parallel power/refrigeration cogeneration Kalina cycle system

A parallel power/refrigeration cogeneration Kalina cycle (PPR-KC) system with adjustable refrigeration/power ratio that developed on the basis of the triple-pressure Kalina cycle system was analyzed. The PPR-KC system can produce refrigeration with temperature ranging in either air conditioning or ice making by switching the exhaust refrigerant vapor to the mid-pressure absorber or to the low-pressure one. The influences of the dilute solution from generator to the destination of either mid-pressure absorber (plan A) or low-pressure absorber (plan B) via recuperators on the performances of the PPR-KC system for air conditioning were investigated. The results show that the PPR-KC system matches well the heat source in cascade arranged boiler and generator thus showing excellent thermal performance by optimizing the solution concentrations, boiler superheat and other parameters. Under the given temperatures of heat source 400°C and cooling water 30°C respectively, the variation trends of the cycle parameters and performances of both plan A and plan B are presented. The power recovery efficiency of plan B is about 1.6% higher than that of plan A. When boiler bubble point temperature difference increases from 20 K to 60 K the refrigeration/power ratio of plan B climbs from 0.475 to 1.192.

Condensation heat transfer and pressure drop characteristics of zeotropic mixtures of R134a/R245fa in plate heat exchangers

Zeotropic mixtures have shown great potential to improve the system efficiency compared with the use of pure fluids as the working fluids. However, there is a lack of analysis of the heat transfer during the phase change of zeotropic mixtures in plate heat exchangers, which is a common heat transfer device used as the evaporator and condenser in these systems. This paper presents an experimental analysis of the flow condensation heat transfer and pressure drop characteristics of zeotropic mixtures in a plate heat exchanger. The objectives are to obtain prediction methods for the heat transfer coefficient and frictional pressure drop and to quantify the degradation of the heat transfer coefficient by using mixtures. Zeotropic mixtures of R134a/R245fa with five different quantitative compositions were experimentally tested with the bubble point temperatures of 30°C to 50°C and various mass fluxes. The experimental results indicate that condensation of the mixtures is governed by a shear-controlled process, similar to what happens with pure fluids. Moreover, the heat transfer degradation of the zeotropic mixture caused by the mixture effects increases with decreasing condensation temperature and mass flux. There is a 48% maximum decrease in the heat transfer coefficient for the mixture of R134a/R245fa with 0.431/0.569 in mass fraction. A modified Silver-Bell-Ghaly method provides a good prediction for the heat transfer data with a mean absolute percentage deviation of 12.2%. A pure-fluid correlation developed in a previous work by the authors enables a prediction with an 8.6% mean absolute percentage deviation for the pressure drop data.

Condensation and vaporization heat transfer of low-GWP mixtures

The present work investigates the heat transfer performance of non-azeotropic ternary low-GWP (Global Warming Potential) mixtures during condensation and vaporization inside a 8.0 mm inner diameter channel. The tested mixtures are R455A, which is a ternary blend of R32, R1234yf and R744 (21.5/75.5/3.0% by mass composition), and R452B, which is a ternary blend of R32, R1234yf and R125 (67.0/26.0/7.0% by mass composition). R455A presents a GWP100-years value equal to 146 and a temperature glide of 10 K at pressure p=17.6 bar, while R452B is characterized by higher GWP, equal to 676, but lower temperature glide, about 1 K at p=22.9 bar. Condensation tests have been run with the two mixtures R455A and R452B at a mean saturation temperature (average value between dew point and bubble point temperatures at constant pressure and given composition) equal to 40 °C and mass velocity ranging between 100 and 600 kg m−2 s−1. Flow boiling tests have been performed at around 18 °C mean saturation temperature and mass velocity ranging between 200 and 400 kg m−2 s−1. The effects of vapor quality, mass velocity and heat flux on the heat transfer coefficient are investigated. Moreover, the adoption of zeotropic mixtures poses the problem of how to extend the correlations developed for pure fluids. In the present paper, the contribution of the mass transfer resistance is assessed and the corrections needed in the models are discussed.

Predicting phase equilibrium of aqueous sugar solutions and industrial juices using COSMO-SAC

COSMO-SAC model was used to predict bubble point pressure, bubble point temperature, water activity, freezing point depression and solubility of sugars in aqueous solutions. COSMO-SAC is based on quantum chemistry computations and has a high predictive character, not requiring a specific parameter calibration for each application. For most systems studied, the results obtained were close to experimental data, with relative mean errors varying from 0.1% to 6.4% for vapor–liquid equilibrium. Solubility results with COSMO-SAC presented the same tendency observed in experimental data, but with higher deviations, probably due to the fact that the loss of crystalline structure in sugars is a kinetic process more than a thermodynamic melting, and does not occur at a single temperature with a constant enthalpy value. COSMO-SAC model was also used to predict industrial juices water activity, bubble point temperature, and freezing point depression. Very low deviations from experimental data were observed for COSMO-SAC calculations, similar to those found for simpler sugar solutions.

LEAPS2: Learning based Evolutionary Assistive Paradigm for Surrogate Selection

We propose a learning-based paradigm (LEAPS2) to recommend the best surrogate/ with minimal computational effort using the input-output data of a complex physico-numerical system. Emulating the knowledge pyramid, LEAPS2 uses several attributes to extract system information from the data, correlates them with surrogate performances, stores this attribute-surrogate knowledge in a regression tree ensemble, and uses the ensemble to recommend surrogates for unknown systems. We implement LEAPS2 using data from 66 diverse analytical functions, 18 attributes, and 25 surrogates. By progressively adding data, we demonstrate that LEAPS2 learns to improve computational efficiency and functional accuracy. Besides, the architecture of LEAPS2 enables its evolution via more attributes and surrogates. We employ LEAPS2 to recommend surrogates for estimating the bubble and dew point temperatures of LNG. Interestingly, our assistive tool suggests a different surrogate for each temperature, and hints that DPT may be harder to approximate than BPT.

Helmholtz free energy equation of state for propane and R134a binary mixture

In this work, a Helmholtz free energy equation of state for R290 + R134a based on the multi-fluid approximations model was developed to describe the thermophysical properties of the binary mixture. The present equation shows more competitive than the default equation in REFPROP 9.1 (Lemmon et al., 2013). It covers a temperature range of (252–400) K and pressures up to 6.1 MPa. The estimated standard uncertainties of the present equation are 0.70% and 0.90% for the bubble point and dew point pressures, 0.26 K and 0.29 K for the bubble point and dew point temperatures, 0.13% and 0.60% for the saturated liquid and vapor densities, respectively. The main purpose is to provide a useful model for R290 + R134a, and thus to promote its better applications for the design and optimization of the refrigeration systems.

Design and control of fully heat-integrated pressure swing distillation with a side withdrawal for separating the methanol/methyl acetate/acetaldehyde ternary mixture

In the industrial manufacturing process of polyvinyl alcohol, there is inevitably a small amount of acetaldehyde in the alcoholysis solution (methyl acetate/methanol mixture), the accumulation of which may decrease the purity of product. The effect of acetaldehyde on the separation of homogeneous azeotrope of methyl acetate and methanol via fully heat-integrated pressure swing distillation (FHI-PSD) is investigated. A PSD process with a side withdrawal is proposed and proved to avoid the accumulation of acetaldehyde in the system effectively. The optimum separation configuration conditions are based on the minimum total annual cost (TAC) analysis. In the steady-state design, the simulation reveals that the process has the minimal TAC when operating pressure of the HPC is 10atm. A conventional pressure-compensated temperature control (CS3) and a new temperature difference control (CS4) are compared in Aspen Dynamics. Both of them can eliminate the influence of pressure fluctuation on bubble points at the sensitive plates and perform well even for large feed disturbances. However, it is easier to design CS4 as CS4 doesn’t require complex bubble point temperature calculation compared with CS3. Therefore, CS4 is suggested to be another favorable and viable control scheme for PSD process, which may show superiority in industrial application.

Experimental study of heat transfer during pseudo-dropwise condensation of water-ethanol and water-isopropanol vapor mixtures on a vertical tube

In the present study experimental heat transfer data on condensation of almost immobile water-ethanol and water-isopropanol vapor mixtures on the vertical smooth copper tube 100 mm long with an outer diameter of 12.0 mm were obtained. Experiments for water-ethanol mixture were carried out at mass concentrations of ethanol from 0.4 to 16% in the vapor phase, and for a water-isopropanol mixture - from 0.6 to 8.4%. The pressure was 0.12…0.13 MPa, vapor-to-surface temperature difference varied from 2 to 40K. The experimental data are represented as dependency of heat transfer coefficient and heat flux on the vapor-to-surface temperature difference. The results of high-speed photography of the condensation process are discussed. It is noted that the transition from film mode to pseudo-dropwise condensation occurs when vapor-to-surface temperature difference is close to dew point - bubble point temperature difference for a given composition of the mixture. According to experimental data, the diffusion thermal resistance and thermal resistance of the liquid phase at different concentrations of the mixture were calculated.

Grey relational analysis coupled with principal component analysis for optimization of the cyclic parameters of a solar-driven organic Rankine cycle

PurposeThe purpose of this paper is to investigate the effect of four controllable parameters (fuel mixture, evaporation bubble point temperature, expander inlet temperature and condensation dew point temperature) of a solar-driven organic Rankine cycle (ORC) on the first-law efficiency, the exergetic efficiency, the exergy destruction and the volume flow ratio (expander outlet/expander inlet).Design/methodology/approachNine experiments as per Taguchi’s standard L9 orthogonal array were performed on the solar-driven ORC. Subsequently, multi-response optimization was performed using grey relational and principal component analyses.FindingsThe results revealed that the grey relational analysis along with the principal component analysis is a simple as well as effective method for solving the multi-response optimization problem and it provides the optimal combination of the solar-driven ORC parameters. Further, the analysis of variance was also employed to identify the most significant parameter based on the percentage of contribution of each cyclic parameter. Confirmation tests were performed to check the validity of the results which revealed good agreement between predicted and experimental values of the response variables at optimum combination of the input parameters. The optimal combination of process parameters is the set with A3 (the best fuel mixture in the context of optimal performance is 0.9 percent butane and 0.1 percent pentane by weight), B2 (evaporation bubble point temperature=358 K), C1 (condensation dew point temperature=300 K) and D3 (expander inlet temperature=370 K).Research limitations/implicationsIn this research, the Taguchi-based grey relational analysis coupled with the principal components analysis has been successfully carried out, whereas for any optimized solution, it is required to have a real-time scenario that may be taken into consideration by the application of different soft computing techniques like genetic algorithm, simulated annealing, etc. The results generated are purely based on theoretical modeling, and, for further research, experimental analyses are required to consolidate the generated results.Originality/valueThis piece of research work will be helpful to users of solar energy, academicians, researchers and other concerned persons, in understanding the importance, severity and benefits obtained by the application, implementation and optimization of the cyclic parameters of the solar-driven ORC.

Modeling solubility of CO2/hydrocarbon gas in ionic liquid ([emim][FAP]) using Aspen Plus simulations.

The Peng-Robinson equation of state with quadratic van der Waals (vdW) mixing rule model was chosen to perform the thermodynamic calculations in Flash3 column of Aspen Plus to predict the solubility of CO2 or any one of the hydrocarbons (HCs) among methane, ethane, propane, and butane in an ionic liquid 1-ethyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate ([emim][FAP]). Bubble point pressure, solubility, bubble point temperature, fugacity, and partial molar volume at infinite dilution were obtained from the simulations, and enthalpy of absorption, Gibbs free energy of solvation, and entropy change of absorption were estimated by thermodynamic relations. Results show that carbon chain length has a significant effect on the bubble point pressure. Methane has the highest bubble point pressure among all the considered HCs and CO2. The bubble point pressure and fugacity variation with temperature is different for CO2 as compared to HCs for mole fractions above 0.2. Two different profiles are noticed for enthalpy of absorption when plotted as a function of mole fraction of gas soluble in IL. Partial molar volume of CO2 decreases with increase in temperature in [emim][FAP], while it is increased for HCs. Bubble point temperature decreases with increase in the mole fraction of the solute. Entropy of solvation increases with temperature till a particular value followed by a decrease with further increase in temperature. Gibbs free energy change of solvation showed that the process of solubility was spontaneous.

Design and control of a cryogenic multi-stage compression refrigeration process

Providing refrigeration at very low cryogenic temperatures requires the use of several stages of compression refrigeration with progressively lower boiling point refrigerants in the various stages. The cascade of cycles ultimately rejects heat to cooling water, but the working fluid at each stage removes heat from a lower-temperature source and rejects this heat plus the compressor work in that stage to a higher-temperature sink. The design of these systems appears to be only qualitatively discussed in the literature, and no discussion of their plantwide dynamic control has been found.This paper presents a quantitative design of a three-stage compression refrigeration process that uses methane, ethylene and propylene as the working refrigerant fluids in the three stages. Heat is removed in the condenser of a cryogenic distillation column separating carbon monoxide and methane. The bubble-point temperature of carbon monoxide at 13.9bar is −158°C. The distillation column condenser is cooled by evaporating boiling liquid methane at −163°C. The second stage has an evaporator with boiling ethylene at −106.7°C. The final stage has an evaporator with boiling propylene at −25.9°C. An effective plantwide control structure is developed and tested.