Energy conservation through management, energy conservation through concepts, energy conservation through technology

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Energy conservation through management, conceptual approaches, and technology – A review of Harbin Petrochemical Company’s energy conservation efforts in 2007 by Qi Tiezhong and Fan Jingcai, Harbin Petrochemical Company, China National Petroleum Corporation. Preface: Harbin Petrochemical Company is a large state-owned enterprise under China National Petroleum and Natural Gas Group Corporation. It is a fuel-based refining company that consumes over 400,000 tons of standard coal per year; it is considered one of the key energy-consuming enterprises in the country, and it is also one of the enterprises involved in the “11th Five-Year Plan” energy conservation initiative. The company has always attached great importance to energy conservation and emission reduction, considering energy and water savings to be one of the key aspects of oil refining operations. In recent years, the company has integrated energy-saving practices throughout the entire production process by adopting new concepts, improving operational mechanisms, using advanced technologies, and refining daily management. Through continuous exploration and practice, new approaches to energy conservation that rely on effective management, conceptual strategies, and technological solutions have been developed. In 2007, despite factors such as frequent adjustments to crude oil processing plans, the commissioning of multiple new units, the implementation of safety and environmental protection measures, and construction activities, the company managed to reduce its energy consumption to new lows. The energy consumption per ton of refined oil was 78.49 kilograms of standard oil, while the water consumption per ton was 0.75 tons, demonstrating good results in terms of energy and water conservation. The main data are shown in Table 1. Table 1: Key Economic Indicators of Harbin Petrochemical Company – Units: 2007, 2006
Processing loss %: 0.65, 0.82; Difference: -0.17
Energy consumption per unit of output (kg of standard oil per ton): 10.28, 10.87; Difference: -0.59
Energy consumption in refining (kg of standard oil per ton): 78.49, 83.09; Difference: -4.6
Self-use rate %: 7.06**, 9; Difference: -0.53
Fresh water consumption per ton: 0.75, 0.89; Difference: -0.14

1. Improve systems and enhance the energy-saving management framework to achieve effective energy savings.
1.1 Clarify responsibilities and establish a proper organizational structure. In 2007, in order to strengthen energy and water conservation efforts and advance such initiatives more effectively, the previous fragmented multi-departmental approach was replaced by a leadership team for energy and water conservation headed by the general manager and the party committee leader. An office for energy and water conservation was set up under this team, with senior technical experts serving as its directors; experienced full-time and part-time managers were also assigned to it. The leadership team was responsible for coordinating and resolving major issues related to energy and water conservation. Each workshop and directly affiliated unit has also established a leadership group for energy and water conservation, thus creating a comprehensive management system for energy and water conservation from top to bottom. Energy and water conservation management has been integrated into the company’s QHSE system, with clear definitions of the responsibilities of team members and streamlined business relationships among various functional departments. The Energy and Water Conservation Office is responsible for planning, statistics, evaluation, on-site inspections and supervision, as well as conducting in-depth field research. It puts forward recommendations regarding issues such as unreasonable energy use and suboptimal energy utilization, and oversees the implementation of corrective actions, thereby making energy and water conservation management more rational. This facilitates the advancement of energy and water conservation efforts, enables a PDCA cycle-based management approach to energy conservation, and promotes continuous improvement in energy efficiency. 1.2 Improve systems to achieve standardization and institutionalization of energy conservation management. To ensure that energy conservation management is carried out in an orderly manner, the company has established and improved relevant management systems. It has formulated and refined procedural documents and operational guidelines such as the \"Harbin Petrochemical Company Energy Conservation Management Procedures\" and the \"Harbin Petrochemical Company Energy Consumption Statistics Management Regulations\", covering all aspects of energy receipt, distribution, and usage, as well as key energy-consuming equipment. Through the establishment and improvement of management systems, the standardization of the company’s energy and water conservation management has been ensured. 1.3 Establish a monitoring and supervision mechanism for energy and water conservation, with equipment and production operations as the focus; by leveraging the MES system, ensure that consumption of water, electricity, steam, air, etc. is under real-time monitoring and control. Through mechanisms such as production coordination meetings, production scheduling meetings, regular meetings on energy and water conservation, and economic activity analysis sessions, a management framework featuring daily inspections and supervision, weekly reports and evaluations, monthly summaries and plans, and quarterly analyses and improvements has been established. By putting these systems in place, every department and employee can always be aware of and keep track of the efforts being made in terms of energy and water conservation, thereby integrating these practices into the work of all departments and employees. This approach boosts everyone’s enthusiasm for energy and water conservation, thus facilitating the advancement of such efforts. 1.4 Implement strict quota management and improve the assessment system. Over the years, Harbin Petrochemical Company has maintained strict quota management, with each unit setting its consumption targets for the following year at the end of each year. The quota indicators cover every energy-consuming process in the entire plant and involve every employee, ensuring that there are indicators everywhere. In the past two years, while continuously refining the accounting for individual units, energy and water conservation targets have been included in the performance contracts signed between the company and its various departments. A strict reward and punishment system ensures that the concept of \"saving energy and water means increasing efficiency\" is truly transformed into the conscious action of employees. 1.5 Strict measurement and monitoring management: Energy measurement is the foundation for carrying out energy-saving efforts; evaluations of technical upgrades, performance assessments, and operational analyses all rely on accurate data from energy measurement and monitoring. In recent years, Harbin Petrochemical Company has allocated a certain amount of funds each year to upgrade its measuring instruments, thereby improving its energy measurement system. In addition, the Harbin Energy Conservation Inspection Center and the energy conservation inspection center of the joint-stock company are regularly invited to monitor key energy-consuming equipment, which provides effective guidance for the implementation of energy and water conservation efforts. 1.6 Conducting inspections for leaks in underground water pipelines: Since most of the main water pipelines are buried underground, corrosion over time often leads to leaks, and these leaks are not easily detectable unless they reach the surface; this can result in significant water loss. Over the past two years, we have worked together with leak detection companies to identify leaks in the underground water pipelines during periods when there were abnormalities in the company’s water usage or when leaks were likely to occur. By addressing these leaks promptly, we were able to reduce the overall water loss rate for the company. In 2007, 9 leak sites were detected, resulting in a total water loss of 27.34 tons per hour. 2. Collaboration with Shell to unlock potential and foster a corporate culture of energy conservation. Harbin Petrochemical Company has a history of over 30 years; its system pipelines are highly complex, some of its equipment is outdated, resulting in relatively high energy consumption per unit of production. After several years of efforts to save energy and reduce consumption, there is increasingly less room for improvement in terms of energy and water conservation performance. To accelerate the shift in mindset, we have expanded the scope of technical exchanges and research. By establishing connections with key energy-saving consulting firms both domestically and internationally, we bring in external expertise to uncover a company’s potential for energy savings, carry out energy optimization efforts, and ultimately achieve the goals of reducing energy consumption and increasing efficiency. “Shell Global Solutions is a technology company under Shell that provides optimization solutions such as energy-saving technologies. In 2007, we collaborated with Shell Global Solutions to assess a company’s energy consumption. A total of 24 PFI projects (solutions that require improvement; the plans have been largely finalized and can be put into implementation) and 9 AFI projects (areas that can be improved but require further analysis to determine the specifics) were identified. All 33 items cover four aspects: process operation, instrument control, maintenance, and utility systems. After the implementation of the first 7 \"zero-investment\" projects, the overall energy consumption of the entire plant was reduced by 3.3 kilograms of standard oil per ton, showing initial success in the implementation of these projects. Upon the full implementation of all 33 projects, it is expected that the overall energy consumption of the plant can be reduced by 12 kilograms of standard oil per ton. The zero-investment projects implemented in 2007 were all adjustment and optimization projects. These projects addressed the issues present in Chinese design practices, such as excessive design margins, device loads that did not meet the designed values, and a lack of consideration for efficient energy utilization across the entire plant. Measures such as implementing pressure-reduction operations on distillation towers to save energy, using steam at 1.3 MPA from Turbine Unit No. 1 of the power plant specifically for MEK production, reducing the hydrogen-to-oil ratio through hydrogenation, and lowering the temperature drop in the inlet pipelines of the exhaust fans were carried out. Pressure energy resulting from fuel use, electricity consumption, as well as temperature and pressure reduction was recovered. Through the implementation of these projects, the production processes were further simplified, the system configuration was optimized, and reductions were achieved at the source, during operations, and at the system level. Working with Shell Global Solutions involves not only making use of its advanced technologies but, more importantly, adopting its innovative concepts. Based on summarizing the advanced energy-saving concepts of this organization and domestic professional institutions, we have developed our own energy-saving philosophy: first, reduction at the point of use; second, stabilization in operational processes; third, recycling in resource utilization; fourth, institutionalization of performance evaluation; fifth, a culture of conservation in mindset. In practice, we prioritize these concepts; by educating employees about advanced energy-saving ideas, we help them understand the situation, organize their work approaches, clarify their goals, and consciously apply these concepts to guide energy-saving efforts. This has played an important role in facilitating energy and water conservation initiatives. Through the dissemination and implementation of advanced concepts, we have come to realize that effective energy and water conservation relies on fostering awareness, presents challenges in terms of process control, and requires persistence. Among these, reducing consumption at the source is a prerequisite; stabilizing operational processes is the core; institutionalizing performance evaluation is a guarantee; fostering a culture of conservation in terms of mindset is the driving force; and achieving circular utilization of resources is the goal. Only by adhering to the principle of giving priority to concepts, implementing solid and effective measures in practical work to turn the saved energy into clean, environmentally friendly, and recyclable energy, and continuously improving the circular economy system, can we push energy and water conservation efforts to new heights. 3 Implement reduction, maintain stable production, and adopt energy-saving concepts. 3.1 Plan and design for energy integration optimization to ensure reduction at the source. Energy saving does not refer to saving energy in individual devices, or in single systems or workshops; rather, it involves energy saving across all aspects and throughout the entire process. Energy integration optimization in planning and design represents the most effective way to achieve energy savings. In the early stages of key project constructions such as restructured hydrogenation complexes and catalytic capacity expansion upgrades, we consider the energy utilization of the new facilities in terms of the overall energy use across the entire company. By combining the energy-saving plans developed by South China University of Technology with the project designs from Beijing Design Institute, we ensure seamless integration between the existing facilities, utility systems, and the new projects, as well as the integration of the steam systems, fuel systems, and low-temperature heat systems of both old and new facilities. When selecting equipment for new installations, full consideration is given to energy efficiency; large-scale, long-operating-life, and high-energy-efficiency process technologies and equipment are employed to achieve optimized energy integration across new and existing installations and systems. 3.2 Emphasize the operational control of KPI indicators to ensure the long-term operation of the equipment. Energy savings must be achieved on the premise of safe and stable production, and long-term operation of the equipment represents the greatest opportunity for energy savings in manufacturing enterprises. Through research, analysis, and practical operation experience, the company has established strict guidelines for the overall operation of the plant. It has identified the key KPI indicators related to production processes and energy conservation, and incorporated these indicators into the operation cards used by operators. This ensures that all relevant metrics are clear and easy to remember, allowing operators to make timely adjustments according to these cards in case of production fluctuations, thereby ensuring optimal operation of the entire plant system. Technical efforts were made to ensure long-term operational efficiency across the entire plant; operation plans were adjusted as needed to optimize the production processes of the refining and chemical units. This approach effectively prevented unplanned shutdowns of these units, enabling stable high-load operation. Emphasis is placed on the management of safety and technical equipment such as equipment interlocks and process interlocks; activities are carried out to maintain equipment in optimal condition, ensuring controlled operation of equipment management. A set of atmospheric and vacuum distillation units, as well as a gas separation unit, have achieved a five-year long-term operation period, while the catalytic unit has achieved a four-year long-term operation period. 3.3 Strengthening the optimization of operational management for equipment: The operational parameters of equipment can be adjusted within certain limits; such adjustments ensure the safe and stable operation of the equipment as well as meet the requirements for product quality control. However, these limits are not necessarily the most economical or optimal ones. Therefore, optimizing the operation of equipment in order to achieve energy savings is a key task when ensuring its safe and stable operation. During the summer of 2007, operational optimizations were carried out on the top of the three-catalyst fractionation tower; the flow rates of air cooling and low-temperature heat exchange were adjusted appropriately. This approach enabled the maximum amount of heat to be extracted while ensuring production safety, thereby achieving the goal of eliminating the need for steam supply to the reboiler of the propane column in the gas separation unit – resulting in a savings of 120 tons of steam per day. Heating furnaces are important energy-consuming devices in refineries. By implementing 12 measures such as strict control of the exhaust temperature and excess oxygen levels in heating furnaces, as well as oxygen-deficient regeneration in catalytic converters, Harbin Petrochemical has managed to reduce oil refining energy consumption by 2.5 kilograms of standard oil per ton, while saving 200,000 tons of water. 3.4 The storage and transportation system reduces the heat consumption required for maintaining the temperature of storage tanks, thereby achieving reduction in energy use. In 2007, Harbin Petrochemical adopted measures such as reducing crude oil inventory, adjusting the parameters for maintaining tank temperatures, shortening the storage period for refined oils, and utilizing the low-temperature waste heat from refining units as a heat source for maintaining tank temperatures – all of which helped to **reduce the heat consumption of the storage and transportation system**. Furthermore, by taking measures such as ensuring the steady operation of the equipment, product quality is controlled at the source; this reduces the need for oil blending, thereby cutting down storage and transportation losses in the oil tank areas as well as the energy consumption associated with blending, and enabling more rational utilization of energy in these areas. 3.5 Reducing consumption between units, with widespread adoption of direct material supply. Implementing direct material supply is an important energy-saving measure that further optimizes the energy usage of the entire process system, building on the energy optimization within the units themselves. It aims to minimize overall energy consumption by optimizing the temperatures and flow rates between the devices that supply materials to each other. In the atmospheric and vacuum distillation unit of Harbin Petrochemical Company, a portion of the residual bottom oil is sent to catalytic cracking at a temperature of around 110°C ； Some of it goes to the tank area, where it needs to be cooled to 90°C. This not only increases the cooling load on the atmospheric-pressure units and raises energy consumption for storage and transportation, but it also increases the preheating load on the catalytic units, resulting in the high heat content of the hot streams within those units being underutilized. In 2007, we achieved direct feeding from the atmospheric pressure unit to the catalytic unit through simple modifications, which simplified the process flow between the units and reduced the cooling requirements of the atmospheric pressure unit, as well as the heat required for temperature maintenance during storage and transportation, as well as the energy consumption of the transportation systems. 3.6 Actively carry out winter reduction efforts. Winter production is the season with the highest energy consumption in the north, but it is also the season with the most opportunities for energy savings. In the winter of 2007, Harbin Petrochemical Company took measures to reduce production during that season: it cut off heating in unused buildings and reorganized the heat tracing for the process pipelines of equipment that was not in use ； Adjust the amount of circulating water used to address the issue of excessive short circuits caused by small temperature differences ； Measures such as adjusting the steam consumption to achieve its tiered use helped to reduce steam usage by 20 tons per hour in the winter of 2007 compared to the same period in 2006, thereby cutting the company’s energy consumption by nearly 4 units. 4. Increase efforts in transformation and adopt technological solutions for energy savings, continuously improving the level of energy-saving technologies. Scientific management is the foundation for energy conservation, while technological progress serves as the driving force behind it. Our company places great emphasis on investing in technological upgrades in its efforts to reduce energy consumption. In recent years, despite financial constraints, significant investment has been made in energy-saving technological upgrades. Through such upgrades, research and development efforts, and the application of advanced technologies, the company’s energy-saving capabilities have been continuously improved, which has played a vital role in enhancing the efficiency of energy use and the economic performance of the enterprise. 4.1 Thermal integration between units: Take advantage of the downtime resulting from the long-term maintenance of the catalytic and gas separation units to carry out thermal integration upgrades. Before the renovation, the low-temperature waste heat generated by our company’s three catalytic units was used for heating in winter, as well as for heating the polymerization reactors in the polypropylene plant and for domestic hot water. However, in summer, there was a clear shortage of heat sinks; as a result, this low-temperature heat had to be removed using circulating water and air coolers, resulting in extremely inefficient use of energy ； Meanwhile, the reboilers at the bottoms of each column in the gas fractionation unit use steam as the heat source, with temperatures suitable for low-grade heat. After the commissioning of the heat integration project, not only was the steam used in the reboiler at the bottom of the propylene column in the gas separation unit discontinued, and was the overhead cooler in the distillation tower of the three-catalyst unit taken out of service, but the company’s steam shortage was also alleviated. Seven months of continuous operation reduced the overall energy consumption of the plant by 1.24 units. In 2007, the two-catalyst atmospheric heat integration project was put into operation; this system used a two-catalyst unit to heat the crude distillate in the atmospheric unit, raising its temperature by about 8°C, reducing the load on the heating furnaces, and saving fuel consumption. 4.2 Wastewater purification and reuse: In 1998, our company was the first to utilize three-stage filtration technology to directly reuse qualified wastewater for replenishing circulating water; to date, all water used for replenishing circulating water comes from this purified recycled water. In 2006, our company developed a new approach to reusing refinery wastewater as make-up water for boilers, building on the existing wastewater treatment systems. The secondary wastewater treatment plant utilizes a combination of ultrafiltration and reverse osmosis technologies to carry out advanced treatment of refinery wastewater, enabling the water quality to meet the standards for high-quality reclaimed water. This water is then used to supply water to the boilers in the on-site power plants, resulting in an annual increase of 420,000 tons in the amount of recycled water used. In 2007, the company’s wastewater discharge rate was 0.17 tons per ton of crude oil. 4.3 Optimization of the heat exchange network: Due to limitations in processing capacity, as well as changes in the properties of raw materials and production methods, there are many issues with the heat exchange processes in a constant-pressure plant. Taking advantage of maintenance opportunities, Harbin Petrochemical Company collaborated with South China University of Technology to carry out energy-saving upgrades on one such plant, optimizing its heat exchange network. As a result of these upgrades, the final temperature at which crude oil is cooled increased from 270°C to 305°C, which reduced the consumption of circulating water and lowered the plant’s energy consumption by nearly 1.5 units. 4.4 Sealed loading of large flexible hoses and recovery of oil vapor during loading: Previously, our company loaded gasoline and diesel using small flexible hoses in an open manner. During loading, there are significant volatilization losses, which pollute the environment and pose considerable safety risks. In 2005, a renovation of the large crane loading system was carried out. After the renovation, measurement accuracy was improved, volatilization losses during loading were reduced, the workload on workers was decreased, and operational safety was enhanced. Meanwhile, the increased level of automation helps to effectively prevent accidents caused by overfilling. In 2006, building on the completion of the upgrade to large-diameter piping for loading operations, we became the first company within CNPC’s network to implement a membrane separation technology-based system for recovering oil and gas during loading. Once operational, this system kept the emission concentration of exhaust gases at less than 25 g/m3, with an oil and gas recovery rate of over 95%, thereby reducing potential risks to safety and the environment. 4.5 Closed-loop recovery of condensate Water: In 2007, the company carried out optimization upgrades for the closed-loop recovery of condensate water. After the implementation of these improvements, the problem of inability to reuse condensate water due to the presence of oils in it was resolved ； It eliminates the unreasonable practices of using circulating water to cool condensate in some units, as well as using condensate for air-cooling spray. At the same time, it makes full use of the heat from the high-temperature condensate to heat the deionized water that is heated by steam, thereby increasing the temperature of this deionized water and reducing the amount of deaeration steam required. This results in a closed-loop recycling system for condensate; the condensed water is collected, heated through heat exchange, and then sent to oil and iron removal devices for purification. After purification, the condensed water is used in the power system. Hierarchical utilization of water and steam resources has been achieved, resulting in significant benefits in terms of energy savings and emission reduction. 4.6 By applying the energy \"three-stage\" theory, low-temperature level transformations are implemented in production systems, while low-vacuum transformations are used in non-production systems, thereby achieving hierarchical utilization of energy. Based on the conditions of the low-temperature heat source, the production system reorganizes the flow of the company’s low-temperature systems in accordance with the principle of exchanging heat with low-temperature hot water starting from lower temperatures and progressing to higher ones. The original configuration in which the low-temperature hot water flowed in parallel is changed to a series configuration, thereby enabling hierarchical utilization of thermal energy. Under the current circumstances, this approach allows the project to save 10 tons of steam per hour, reducing the overall energy consumption of the company by 1.8 units. Non-production systems are retrofitted with low-vacuum heating systems in power plants, where the steam turbines use heating water instead of circulating cooling water to cool the condensers. After the modification, the low-vacuum heating system of Unit 1 turbine can recover 15 million kcal/h of thermal energy; meanwhile, the cooling tower and cooling water pumps are shut down, resulting in a savings of 220 kW in electricity consumption and a reduction in the amount of water needed for circulating water by about 40 tons per hour. The direct annual benefit is 2.5 million yuan. 4.7 Online Gasoline Blending Technology: With the implementation of this technology, the tank-based blending method is replaced by a pipeline-based approach, and manual handling is replaced by automated processes. This not only solves the problem of excessive octane value in gasoline but also reduces blending time, eliminates the need for repeated blending, shortens the mixing time for various components before they are fed into the finished product tanks, and lowers energy consumption. 5 Develop long-term plans to ensure that efforts to save energy and water are forward-looking and continuous. In accordance with the planning requirements of the ** and the joint-stock company, the company has set energy-saving targets for the 11th Five-Year Plan: by the end of this period, it aims to achieve a comprehensive energy consumption of 70 kgEO per ton in oil refining, as well as a water consumption of 0.5 tons per ton. To achieve this goal, our company has collaborated with South China University of Technology and Tianjin **Industrial Water Treatment Center to develop a detailed plan for the company’s development during the 11th Five-Year Plan period. In 2007, a partnership was established with Shell Global Solutions to utilize its energy management planning techniques for further tapping into the energy-saving potential of refineries; projects requiring \"zero investment\" have since been launched. While also taking into account the continuity of long-term development, we are working on establishing a planning model that integrates energy conservation in enterprises with sustainable production, thereby enhancing its practicality and flexibility for future development. In short, energy and water conservation efforts involve the entire process of oil refining; only by adopting a completely new approach and achieving energy savings throughout this process can energy consumption be reduced fundamentally. At present, the call to build a resource-conserving society imposes higher demands on the oil refining industry, which is a major consumer of energy. We are aware of our responsibilities and will redouble our efforts to turn our company into a modern enterprise that is energy-efficient, safe, environmentally friendly, and highly efficient. We will strive to produce high-quality products and to build a top-notch refinery!