Energy Intensity Research Articles

Energy intensity of Russia's industrial regions: Assessment and potential for reduction

Subject. This article discusses the issues of development of mining and manufacturing industries and energy consumption growth. Objectives. The article aims to develop strategic recommendations to reduce the energy intensity of some regions' economy, taking into account the potential for the region's development. Methods. For the study, I used various methods of statistical data processing. Results. The article finds that technological and production factors have an impact on reducing the energy intensity of industrial regions. Conclusions. When making decisions aimed at improving the energy efficiency of the region's economy, it is necessary to take into account both the growth rate of the volume of shipped goods of own production and the specifics of energy consumption in the region.

Research on Establishment and Application of Evaluation System of Urban Energy Strategy Development Indicators under the Perspective of Carbon Neutrality

A scientific, comprehensive and integrated assessment of urban energy development is of great significance for the establishment of a clean, low-carbon and efficient urban modern energy system. From the perspective of carbon neutrality, this paper sets 25 evaluation indicators in seven dimensions: energy supply, energy consumption, energy efficiency improvement, clean and low-carbon, safety and reliability, low-carbon transport, and scientific and technological innovation, and constructs a secondary indicator system for evaluating the strategic development of urban energy. The system adopts the hierarchical analysis method to determine the weights of the indicators, the double-baseline progression method to standardize the indicator scores, and finally the weighted composite index method to calculate the level of urban energy strategy development. This paper applies the index system to evaluate the current energy development status of Wenzhou city in 2020 and 2022, and to predict the energy strategy development in 2025 and 2030. The scores of Wenzhou city's urban energy strategy development level in the corresponding four periods are 63.56, 70.59, 77.87 and 85.06, indicating that by 2023, Wenzhou city's urban energy development level will go from medium development to high development. Wenzhou City should accelerate the proportion of renewable energy in the future. It is necessary to complement multiple energy sources and improve the integration of heat, electricity, gas and cold. In terms of end consumption, it is necessary to improve the efficiency of energy use, reduce energy intensity, implement electric energy substitution and form an energy consumption pattern centered on electricity.

LCA of recycling aluminium incineration bottom ash, dross and shavings in a rotary furnace and environmental benefits of salt-slag valorisation

Recycling aluminium in a rotary furnace with salt-fluxes allows recovering valuable alloys from hard-to-recycle waste/side-streams such as packaging, dross and incinerator bottom ash. However, this recycling route generates large amounts of salt-slag/salt-cake hazardous wastes which can pose critical environmental risks if landfilled. To tackle this issue, the metallurgical industry has developed processes to valorise the salt-slag residues into recyclable salts and aluminium concentrates, while producing by-products such as ammonium sulphate and non-metallic compounds (NMCs), with applications in the construction or chemical industries. This study aims to assess through LCA the environmental impacts of recycling aluminium in rotary furnaces for both salt-slag management routes: valorisation or landfill. It was found that this recycling process brings forth considerable net environmental profits, which increase for all the considered impact categories if the salt-slag is valorised. The main benefits arise from the production of secondary cast aluminium alloys, which is not unexpected due to the high energy intensity of aluminium primary production. However, the LCA results also identify other hotspots which play a significant role, and which should be considered for the optimisation of the process based on its environmental performance, such as the production of by-products, the consumption of energy/fuels and the avoidance of landfilling waste. Additionally, the assessment shows that the indicators for mineral resource scarcity, human carcinogenic toxicity and terrestrial ecotoxicity are particularly benefited by the salt-slag valorisation. Finally, a sensitivity analysis illustrates the criticality of the metal yield assumptions when calculating the global warming potential of aluminium recycling routes.

Ammonia production by microbubbles: A theoretical analysis of achievable energy intensity

The present paper studies the energy intensity of ammonia production by a freely oscillating microbubble placed in an infinite domain of liquid. The initial content of the bubble is a mixture of hydrogen and nitrogen. The bubble is expanded isothermically to a maximum radius, then it is “released” and oscillates freely. The input energy is composed of the potential energy of the bubble at the maximum radius, the energy required to produce hydrogen, and the pumping work in case a vacuum is employed. The chemical yield is computed by solving the underlying governing equations: the Keller–Miksis equation for the radial dynamics, the first law of thermodynamics for the internal temperature and the reaction mechanism for the evolution of the concentration of the chemical species. The control parameters during the simulations are the equilibrium bubble size, initial expansion ratio, ambient pressure, the initial concentration ratio of hydrogen and the material properties of the liquid. At the optimal parameter setup, the energy intensity is 90.17GJ/t that is 2.31 times higher than the best available technology, the Haber–Bosch process. In both cases, the hydrogen is generated via water electrolysis.

Research on Energy Conservation and Emission-Reduction Effects of Green Finance: Evidence from China

The energy-saving and low-carbon development model is one of the important symbols of high-quality economic development. This article attempts to study the environmental effects of green finance from both theoretical and empirical perspectives, that is, to test whether green finance policies contribute to achieving energy conservation and emission reduction. This article is based on provincial panel data from 2007 to 2020 in China and constructs a dynamic spatial Durbin model to examine the impact of green finance on environmental pollution and energy intensity. The results indicate that (1) green finance can achieve a dual effect of energy conservation and emission reduction simultaneously and has a significant promoting effect on energy conservation and emission reduction in neighboring regions. This conclusion is still valid after conducting robustness tests. (2) The energy-saving and emission-reduction effects of green finance exhibit significant regional heterogeneity, indicating that the performance of green finance is more outstanding in the eastern region with a higher level of economic development. (3) Mechanism testing has found that green finance can achieve energy-saving and emission-reduction effects through four channels: environmental regulation, credit allocation, enterprise profits, and enterprise innovation. Therefore, in order to further promote high-quality economic development, we need to build a comprehensive and multi-level green finance system, enrich the green finance policy toolbox, and smooth the transmission channels of green finance to promote green and stable economic development.

Effect of waste clay brick powder on microstructure and properties in blended oil well cement pastes at HTHP conditions

The use of waste materials to improve the thermal stability of oil well cement (OWC) at high temperature and high pressure (HTHP) conditions has received increasing attention. This study investigated the performance of sustainable blended OWC pastes by recycling waste clay brick powder (CBP) as a partial substitute for commercial high temperature resistant additives (silica flour, SF). The main objective was to assess the impact of these substitutions on the hydration, microstructure and mechanical properties of blended OWC. CBP was incorporated at substitution rates of 25 wt%, 50 wt%, 75 wt% and 100 wt% by weight of SF. These pastes were firstly precured at 50 °C for 7 days (to simulate the primary cementing operation prior to steam injection), and then thermally cycling cured at 300 °C/13.0 MPa (to simulate the steam injection process). The study conducted comprehensive tests and analyses, including compressive strength, gas permeability, hydration products and microstructural analyses. The results showed that the suitable substitution rate of CBP in this study was 25 wt%-50 wt%. At these substitution levels, the blended OWC pastes had good compressive strength (18.5 MPa and 17.9 MPa) and low gas permeability (3.1 × 10−3 mD and 4.51 × 10−3 mD). From the environmental and economic analyses, the energy intensity and CO2 emissions of all blended OWCs were significantly lower compared to those of conventional OWC. Meanwhile, the cost of blended OWC in this study was significantly lower compared to that of the commercial SF-OWC system. Overall, this study highlighted the potential of recycling waste materials to promote raw material sustainability and improve the performance of OWC pastes at HTHP conditions.

Towards zero-carbon cities: how does environmental information disclosure impact the risk of carbon locking?

Utilizing panel data from 119 cities spanning from 2013 to 2019, the study rigorously investigates the influence of environmental information disclosure (EID) on mitigating the risk of urban carbon lock-in through the application of both two-way fixed effects and spatial econometric models. The findings robustly indicate that EID plays a significant role in facilitating carbon unlocking within cities, a conclusion that remains steadfast even after addressing potential endogeneity issues. Mechanistically, it is revealed that EID can effectively decrease the risk of carbon lock-in by enhancing urbanization levels and reducing energy intensity. Furthermore, the study unveils that the efficacy of EID in curbing urban carbon lock-in risk is also contingent upon factors such as carbon intensity, population size, and environmental quality, highlighting the multifaceted nature of EID's impact on urban carbon management. Specifically, the increase in carbon intensity, the expansion of population size, and the deterioration of environmental quality will reduce the carbon unlocking effect, which may not be conducive to the achievement of the goal of "carbon neutrality" in cities. The spatial effect test found that EID and carbon locking risk are both spatially significant positive autocorrelation, the deepening of local EID can significantly cut the risk of carbon locking in neighboring cities, and the urbanization pathway and energy saving pathway exist both locally and in neighboring places.

Evaluating the role of inkjet printing in perovskite solar modules manufacturing using mathematical modeling

Enormous gains in efficiency over the last decade have pushed perovskite solar cells towards the cusp of entering into the mass production phase. Given the solution-phase processability and low energy intensity of several techniques, many techniques have been explored to manufacture these cells and modules. Among them, inkjet printing has shown potential for fabricating all the active layers while also achieving higher efficiencies along with the benefits of lower cost and high material efficiency. In this article, we focus on the application of mathematical modeling of the process and understanding the impacts of different decision variables on key performance indicators at various levels. In particular, the screening of decision variables space and their effect on final key performance indicators related to the complete solar module are discussed, highlighting the effectiveness and limitations of using such mechanistic models for manufacturing system optimization.

Dynamics between energy intensity and carbon emissions: What does the clustering effect of labor and capital play?

Energy depletion and environmental degradation have emerged as pressing concerns in the era of China's high-quality green economic development. We present an integrated framework that incorporate energy consumption intensity, industrial clustering, and carbon emissions into the STIRPAT framework. Our study examines 30 Chinese provinces from 2006 to 2017. Unlike previous analyses, our study measures industrial clustering from two dimensions: labor and capital clustering. Specifically, the benchmark results confirm that a 1% increase in energy consumption intensity will, on average, raise regional carbon emission intensity by 0.03389%. Moderating analysis shows that labor and capital clustering significantly lower carbon emission intensity by reducing energy consumption. These findings have been consolidated after performing a panel vector autoregressive model. Interestingly, the promoting effect of energy consumption intensity on carbon emission intensity tends to be tightened when labor clustering surpasses a threshold. In contrast, the corresponding effects substantially weaken after capital clustering exceeds a threshold. In all, these findings provide new evidence to understand the energy-emission nexus from an industrial clustering perspective.

Spatial-temporal differentiation and influencing factors of carbon emission trajectory in Chinese cities - A case study of 247 prefecture-level cities

Cities, where human energy activities and greenhouse gas emissions are concentrated, contribute significantly to alleviating the impacts of global climate change. Utilizing the China Carbon Emissions Accounting Database (CEADs) to provide carbon dioxide emission inventories for urban areas in China at the prefecture level, this study closely examines the historical evolution trajectories of carbon emissions across 247 urban units from 2005 to 2019. The logarithmic cubic function model was employed to simulate these trajectories, evaluating urban emission peaks and classifying the different carbon emission trajectories. Further, the Geographical and Temporal Weighted Regression model was employed to explore spatiotemporal traits and essential variables that impact the variations in carbon emissions among four identified trajectory types. Our results showed that Chinese urban carbon emission trajectories can be classified into four categories: a) peaking emissions, b) fluctuating growth, c) continuous growth, and d) passive decline. Specifically, 43 cities, primarily in North China, proactively attained their emission peak post-2010, driven by the reduction in secondary industry and energy intensity. 90 cities, largely industrial hubs in the southeast coast and inland, reached an emission plateau around 2015, exhibiting fluctuating growth due to dependencies on secondary industries. 101 cities, predominantly located in western and central regions, demonstrated a clear upward trend in carbon emissions, propelled by rapid urbanization and heavy industry-oriented economic development. Lastly, 13 cities, typically in the northeastern and southwestern regions, experienced a passive decline in carbon emissions, attributable to resource depletion or economic downturns. It is evident that China's city-level carbon peaking has demonstrated some effectiveness, yet considerable progress is still required.

Simulation and Forecasting Study on the Influential Factors of PM2.5 Related to Energy Consumption in the Beijing–Tianjin–Hebei Region

It is still necessary to regularly investigate the breakdown of socio-economic elements as a starting point for analyzing the effects of diverse human production activities on PM2.5 intensity from industrial and regional viewpoints. In this paper, the emission factor model was adopted to measure PM2.5 emissions in the Beijing–Tianjin–Hebei (BTH) region at the regional and industrial levels. The logarithmic mean Divisia index (LMDI) decomposition model was employed to analyze the factors affecting PM2.5 emissions related to energy consumption in the BTH region at the regional and sectoral levels. Building on this foundation, a system dynamics (SD) model was established to make a prediction regarding PM2.5 pollution in the BTH region in 2025. This study found that secondary industry was a major source of PM2.5 emissions in the BTH region. Coal remained the main form of energy consumption in the BTH region. Secondly, the effect size of the factors affecting PM2.5 intensity ranked in the order of energy intensity, energy structure, and industrial structure. Thirdly, in 2025, PM2.5 emissions in the BTH region will decline appreciably, but there is still a certain gap in terms of meeting the targets of “the 14th Five-Year Plan” between the three provinces and cities. These results indicate that the BTH region should achieve the effective management of PM2.5 pollution at the source through the following initiatives: it is necessary to carry out the continuous adjustment of energy structures to gradually increase the proportion of clean energy; we must steadily promote the decline in energy intensity reduction, and gradually strengthen scientific and technological innovation; and we must continue to promote the optimization of the industrial structure and increase the proportion of tertiary industry every year.

Tourism Transport-Related CO2 Emissions and Economic Growth: A Deeper Perspective from Decomposing Driving Effects

This study explores the intricate dynamics of CO2 emissions stemming from transport within the tourism sector. It aims to unravel the multidimensional aspects of how transport-related tourism contributes to CO2 emissions and to elucidate the complex relationship between regional economic growth and CO2 emissions from transport-related tourism. Our study employed Logarithmic Mean Divisia Index (LMDI) and Panel Vector Autoregression (PVAR) models to analyze data from 30 Chinese provincial regions between 2010 and 2018. The tourism transport-related CO2 emissions were decomposed into four separate driving effects using the LMDI approach. Then, PVAR models were constructed to reveal dynamic interactions between each driving effect and per capita gross regional product (GRP). Our results demonstrate a decrease in both energy structure effect (tourism transport-related CO2 emissions from energy structure) and energy intensity effect (tourism transport-related CO2 emissions from energy intensity) during the pre-COVID decade. Notably, the positive impulse response of energy structure effect to per capita GRP is observed. However, we found no evidence of a cointegrated relationship between energy intensity effect and regional economic growth, although other factors demonstrated connections. These findings echo the necessity to integrate sustainable practices into the tourism transportation business, especially in the area of energy structure, in order to mitigate adverse environmental effects from tourism. This paper disseminates the main drivers of CO2 emissions in the tourism transport sector and their interrelationship with regional economic growth. It not only guides tourism policymakers in targeting efforts to reduce carbon footprints, but also sets a new benchmark for future studies on CO2 emissions.

Identification of carbon responsibility factors based on energy consumption from 2005 to 2020 in China

In the process of rapid economic development, the relationship between energy consumption and economic development is close and the coupling relationship is complex. The study proposes a method for the assessment of integrated energy consumption factors. In particular, production and consumption driving factors are expressed in relation to the growth of primary energy consumption responsibility in the energy supply chain system. Specifically, based on previous research, the study builds a LMDI decomposition model based on the primary energy consumption responsibility - embodied energy (PECREE) formula. By analyzing the impact of changes in the final commodity quantity, value-added allocation factor, energy intensity, end-use energy consumption structure and primary energy consumption responsibility conversion factor on primary energy consumption responsibility, the study systematically reveals the linkage relationship between product production and consumption on energy consumption changes, and reveals the related driving mechanism of primary energy consumption responsibility growth. We choose China's energy supply system from 2005 to 2020 as a case study, focusing on the impact of changes in economic sectors on primary energy consumption responsibility, and provide a supplementary explanation from the commodity consumption side. The results show that the change of final use quantity is the most important factor causing the increase of primary energy consumption responsibility, but the impact is decreasing year by year. The impact of energy intensity change on primary energy consumption responsibility is mainly dominated by economic sectors with high energy consumption and high energy intensity. The impact of value-added allocation factor requires systematic consideration of energy intensity of economic sectors. The increase of the proportion of electricity in the end-use energy consumption structure of the economic sector promotes the growth of its primary energy consumption responsibility. The reduction of primary energy consumption responsibility conversion factor for electricity is one of the factors that inhibits the growth of primary energy consumption responsibility. Finally, we believe that while meeting the needs of social development and production and life of the people, China is already on the road of adjustment and transformation of its industrial structure and energy structure, and will continue to make progress in the future.

The impact of natural resources rent, renewable energy, and governance on the environmental sustainability—Evidence from resource‐rich countries

AbstractNatural resources are vital in alleviating the effects imposed by human activities on the environment. For this reason, the preservation and wise utilization of natural resources has been emphasized and some laws toward ensuring that natural resources are not wasted have been put in place. However, high rents on natural resources are not sustaining. By following the STIRPAT model, this research seeks to assess the role played by natural resources rent, the rule of law, and renewable energy in alleviating the damage caused to the environment by human activities. The present research furthers the growing body of literature on the topic, which constitutes its primary contribution. To attain this goal, the dataset of the top 10 natural resource‐rich African countries, for the time range 1990 to 2021 is used. The dynamic Cross‐sectional Autoregressive Distributive Lag (CS‐ARDL) which overcomes heterogeneity, cross‐sectional dependence (CD), and dynamics is used in the analysis of the research model. The Augmented Mean Group (AMG) and the dynamic Common Correlated Estimator Mean Group (CCEMG) methods are employed to check the robustness of CS‐ARDL results. The findings illustrate that economic growth, natural resources rent, and energy intensity promote environmental damage, while renewable energy (RE) and the rule of law lessen it. This research advocates for the reduction and stabilization of natural resources rent, extensive use of RE, and improvements in the rule of law to alleviate environmental damage.

Social and economic driving forces of recent CO2 emissions in three major BRICS economies

The study examines the driving factors of total energy-related and power-related (electricity-heat) CO2 emissions for China, India and Brazil, three BRICS countries with vital economic and demographic dynamics. The paper applies decoupling and decomposition analysis in order to investigate the influence of those factors that are prominent in the contemporary literature as well as factors reflecting important social and demographic dynamics which affect the ecological footprint of society. Household size and number of households are introduced into the relevant literature for the first time to reflect demographic factors with substantially different trends from population size, the predominant factor in the existing literature. This novelty together with the simultaneous application of decoupling and decomposition analysis adds importance to the findings of the study, which covers the period of 2000–2018. The results show that increasing income and population significantly enlarge the energy-related CO2 emissions. Household size, number of households and income effects are crucial in the increase of power-related CO2 emissions. The crucial factor for the decrease of energy-related CO2 emissions is the decreasing energy intensity, while for power-related CO2 emissions it is the emission factor effect reflecting the recent shift towards less carbon intensive energy types.

Algorithm for personalization of diet therapy in patients with atrial fibrillation and obesity based on metabolic status assessment

Aim: To develop an algorithm for personalizing the diet therapy of patients with obesity and atrial fibrillation (AF) based on the assessment of the metabolic status.Material and Methods. The study included 100 patients with grade III obesity and paroxysmal AF. All subjects had nonvalvular AF. Anthropometric parameters, actual nutrition, bioimedance analysis of body composition, basal metabolic rate (BMR) were assessed.Results. Changes in basal metabolism by gender were identified. In women – a decrease in the rate of carboydrate oxidation (CHO) (by 27 ± 12.2%, p < 0.05), an increase in fat oxidation (by 48,58 ± 14.6%, p < 0.01). In men – a decrease in BMR (by 26,23 ± 13.6%, p < 0.05), CHO (by 57,18 ± 18.1%, p < 0.01) and protein (by 28,06 ± 12.9%, p < 0.05), increased rate of fat oxidation (by 31,42 ± 10.0%, p <0.05). A hyperphagic pattern of actual nutrition has been established: excess daily energy intensity (by 16–44%), excess of daily intake of proteins (by 34–54%), fats (by 17% in women) and carbohydrates (by 57–72%, p < 0.05). An excessive amount of saturated fat, cholesterol, and added sugar was revealed in the diet. A deficiency in vitamin D intake was found (by 8–16%, p < 0.05). The maximum daily energy requirement for 95% of women is within 2250 kcal/day, for men – 2950 kcal/day.Conclusion. Metabolic status disorders serve as factors of hemodynamic overload, humoral and electrical dysfunction of the heart. Diet therapy is a powerful component in the treatment and prevention of AF. It is advisable to carry out an algorithm for individual correction of the chemical composition and energy value of diet therapy taking into account the optimal metabolic corridor of needs, enriching the diet with vitamin D, eliminating added sugar, cholesterol, sodium, phosphorus, and sources of vitamin K.

Auditing and Analysis of Natural Gas Consumptions in Small- and Medium-Sized Industrial Facilities in the Greater Toronto Area for Energy Conservation Opportunities

This paper presents the findings of fifteen energy audits conducted on industrial sites in Canada’s Greater Toronto Area (GTA). The audits covered a range of industries including food processing, packaged goods, and finishing processes (powder-coating). The primary focus of the audits was to analyze the natural gas consumption and the performance of major-gas-consuming equipment. The audits identified natural-gas-consuming equipment that could be optimized to yield energy and operational cost savings and greenhouse gas (GHG) reduction opportunities. Food production plants’ energy intensity ranges from 5.59 m3/ft2 to 17.73 m3/ft2. Therefore, there is a significant opportunity to improve energy consumption through better technology integration. The results of the audits indicate a trend of an increase in the percentage of non-productive consumption with non-productive time. The proposed energy-saving measures include reducing non-productive natural gas consumption, gas-fired equipment tune-up, optimizing boiler loads, and reducing oven exhaust by using variable frequency drives (VFDs). The findings of this study could be used to develop a demand-side management program specifically for small- and medium-sized industrial facilities in the Greater Toronto Area and other parts of Canada.

Digital economy, energy intensity and carbon emissions: new insights from the TIMG index

ABSTRACT Based on the panel data of 96 countries from 2013 to 2020, this study innovatively adopts the TIMG index to measure global digital economy (DE) and examines the impact of DE on carbon emissions. We find that there is an inverted U-shaped relationship between DE and carbon emissions, and energy intensity is the mediating channel. Heterogeneity analysis reveals that lower-middle-income countries can enter the ‘carbon reduction dividend stage’ of DE faster than high-income and upper-middle-income countries. Our findings provide empirical evidence and policy references for effectively utilizing DE for carbon reduction.

Opportunity or trap - the policy effect of China’s energy quota trading

ABSTRACT This paper assesses the policy effect of the energy quota trading (EQT) policy from the perspectives of energy consumption, economic growth, and energy intensity, based on the panel data of 30 provinces in China from 2006 to 2019. The energy intensity has been decomposed into technical effect and structural effect using the LMDI model. The triple difference method, the corresponding parallel dynamic trend test and the placebo test are employed in this study. The result suggests that the EQT policy is capable of suppressing the growth of energy consumption, and will not dampen economic growth. Moreover, the policy facilitates the decrease of energy intensity in China. The EQT policy has spurred energy technology innovation, improved energy efficiency, and exerted about innovative compensation effects. However, the initial allocation of energy quota is free, thus leading to the structural effect of enterprises converging to high-energy-consumption industries. Compared with the white certificate policy, the EQT policy has some defects in the regulatory mechanism and operating rules. It is imperative for the policymakers to formulate guiding policies when considering the policy shocks of the above low industrialization area on the rapidly developing country.

Enhanced downstream processing of NGL using intensified fluid separation technologies

Downstream processing of natural gas liquids (NGL) provides feedstock needed for plastic production, upgraded fuels and heating, but it is one of the largest high-pressure and energy intensive processes. This original study is the first to integrate novel process intensification options from a holistic viewpoint for the full process covering all sections: 1) NGL recovery, 2) NGL fractionation, and 3) isomerization. Intensified fluid separation technologies (e.g. complex columns, thermal coupling, and heat pumps) are explored and integrated into a full NGL process to improve the energy efficiency and mitigate GHG emissions, and to establish the limits of operation, utility usage, and specific product costs. All NGL processes are rigorously simulated in Aspen Plus, and evaluated based on a fair economic and sustainability analysis.The enhanced recycle split vapor process for NGL recovery results in a full heat recovery for the reboiler of the demethanizer (2.9 MW energy savings), while the enhanced gas subcooled process results in 17.9% reduction of the refrigerant duty, 20.2% reduction of the electrical duty, and 19.9% reduction of the total utility cost. For the NGL fractionation section, heat pump assisted double dividing wall process improves energy intensity for a fraction of the utility cost although requiring external incentives (e.g., carbon tax) to become commercially viable. The total utility costs as well as GHG emissions are reduced up to 30% and 49%, respectively, while the specific product cost reduces to $23.45/t or $24.38/t with carbon tax. The heat pump assisted recycled isomerization process for the last section increased AKI from 65.3 to 89.6, with 19.1% reduction of utility usage and 42.4% reduction of carbon emission.