The upsizing of hydrogenation reactors has led to a significant increase in the demand for large-diameter openings in reactor shells. Compared with traditional head openings, the shell opening structure is subjected to worse stress conditions and is prone to forming failure-prone zones under high-temperature creep. Taking the 2.25Cr-1Mo-V steel hydrogenation reactor shell-nozzle structure as the research object, this paper adopts the Omega creep constitutive model to carry out simulation research on creep damage evolution. The influence laws of opening diameter (600~1000 mm) and operating temperature (444~474 ℃) on creep damage accumulation are analyzed, and the effects of nozzle inner fillet radius (25~100 mm) and nozzle wall thickness (290~390 mm) on opening reinforcement effect are investigated from the perspective of structural design. The results show that the maximum Mises stress zone does not coincide with the location of maximum creep damage; the maximum stress value and its location hardly change with time, while both the magnitude and location of creep damage have obvious time dependence. This indicates that the maximum stress cannot be used as a substitute for the maximum creep damage as the failure criterion in creep strength and life design. The increase in opening diameter and temperature both significantly accelerate creep damage, and a 10℃ increase in temperature can reduce the structural creep life by about 50%. The nozzle inner fillet radius has a limited control effect on long-term creep damage, while increasing the nozzle wall thickness can significantly inhibit the development of damage. The research results clarify the creep damage evolution law of the shell opening structure of large-scale hydrogenation reactors, confirm the necessity of creep damage analysis, and provide a theoretical basis for the opening reinforcement and safety design of equipment.

The PPP project for the comprehensive development of Shankou area in Anqing High Tech Zone involves site leveling of 5.8 square kilometers, characterized by a large-scale one-time site leveling range and significant site elevation difference. It is adjacent to Wanhe River, a tributary of the Yangtze River, Shimen Lake, and multiple ecological polder areas. There are no existing roads inside. The project design focuses on site vertical layout, slope protection, ecological protection, and construction priorities. By weighing the pros and cons, the optimal site design scheme was determined with the aim of reducing investment. This provides reference and guidance for the large-scale site leveling design and construction of the park in the future.

In the fields of natural gas and refining and petrochemical engineering, sulfur recovery serves as a core process for reducing hydrogen sulfide (H₂S) emissions and achieving cyclic utilization of sulfur resources. Traditional sulfur recovery processes suffer from limitations such as complex flow paths and redundant equipment, whereas the selective oxidation short-process technology efficiently simplifies the process flow by using a catalyst to selectively oxidize the H₂S in tail gas into elemental sulfur. This study conducted a comparative analysis of sulfur recovery processes at a natural gas desulfurization station. Results demonstrate that compared with traditional process, the short-process technology achieves significant improvements across key performance indicators: 15% reduction in energy consumption, 8% decrease in carbon emissions, 32% lower capital investment, and 12% reduction in footprint. This technology balances environmental benefits and economic feasibility, providing an efficient and low-carbon solution for sulfur recovery, especially suitable for small-scale natural gas desulfurization stations.

When the medium flows at high speed in pipelines or equipment, it is easy to cause thermowell vibration. If the instrument itself resonates with the process medium, it may lead to the fatigue fracture of the thermowell. By calculating the vibration frequency ratio, a suitable thermowell can be selected. The method of resonance determination may be slightly different for gaseous medium and liquid medium. According to relevant standards and regulations, the appropriate vibration frequency ratio has a fixed numerical range. When the calculation results are not ideal and it is difficult to select a suitable thermowell, solutions such as shortening the insertion length of the thermowell, optimizing the cross-section, and selecting materials with higher stiffness can be used to adjust the vibration frequency ratio to meet safety requirements.

China’s natural gas demand is substantial, accompanied by a high degree of external dependence. Hydrogen, as an alternative fuel, can be transported over long distances through blending into existing gas pipelines, while simultaneously optimizing the national energy supply structure. This study employs TGNET software to conduct steady-state simulations and analyses. The results indicate that for long-distance gas transmission pipelines, when the relative terrain elevation difference (△h) exceeds 200 m, the influence of terrain elevation differences on pipeline pressure loss cannot be neglected. Conversely, in the case of pure hydrogen pipelines (simulated under extreme conditions), due to the low density of hydrogen, the smaller the relative density of the gas at a constant volumetric flow rate, the higher the outlet pressure and the lower the pressure loss. Thus, the impact of elevation differences on pressure loss in gas pipelines is negligible. Based on domestic and international experience regarding optimal hydrogen blending ratios, simulations were conducted with a 15% hydrogen blending ratio. Under identical operating conditions, blending 15% hydrogen into long-distance natural gas pipelines can reduce the pressure loss by 0.1–0.36 MPa, while simultaneously lowering the carbon emission intensity associated with natural gas utilization.

 To address the problems of flow deviation and vortices easily caused by flue gas mixing in the transition section of large double radiant section ethylene cracking furnaces, CFD numerical simulation technology was adopted to systematically study the effects of transition section width, groove structure and side wall inclination angle on the flow field taking this type of cracking furnace in a certain plant as the research object. The results show that the transition section width is a key parameter affecting flow field uniformity, and different width schemes have a significant impact on achieving flow field uniformity. The side wall inclination angle has little effect on the flow field, while the groove structure can improve the flow field but is difficult to implement in engineering due to its complex structure. Finally, a structure of "transition section bottom width benchmark + 350 mm + benchmark side wall inclination angle" is recommended, which provides technical support for the operation of double-hearth cracking furnaces.

To address the gas-solid erosion problem in waste heat boiler heat exchange tubes, this paper proposes a novel inlet structure consisting of a bell-mouth and a long divergent section. Using a Discrete Phase Model (DPM) validated by experimental data, the coupled flow field and erosion behaviors of conventional and novel tubes were compared. The effects of gas velocity, particle mass flux, and particle size on wall wear were systematically investigated. The results indicate that the new structure significantly improves the flow field and inhibits wear. Under varying gas velocities, the peak erosion rate of the novel tube is reduced by 58.8%–66.1%. As the particle mass flux increases, the erosion growth rate of the novel tube slows significantly, achieving a maximum reduction of 72.7%. Furthermore, as the particle size increases, the novel tube consistently lowers the peak wear by 57.1%–70.9%. This study demonstrates that the novel tube effectively optimizes the flow field and significantly weakens the erosion damage caused by gas-solid two-phase flow.

This article systematically explains the technical sources and key clauses regarding support span in GB/T 17116, GB/T 20801 and SH/T 3073 commonly used for calculating the span of pipe supports and hangers in refining and petrochemical units, analyzes the differences between them and their respective application boundaries, points out the problems in the current version, and introduces the specific requirements for the support span of special types of pipelines such as flow-induced vibration pipelines, providing engineering reference for the selection of pipe support span in refining and petrochemical units.

With the capacity expansion of a propylene oxide/styrene monomer (PO/SM) plant, the existing equipment layout of MPK hydrogenation reaction framework can no longer meet the production demands. Focusing on the trickle-bed reactor of the MPK hydrogenation unit and following the principles of gravity flow priority, grouped and symmetric equipment layout, balanced operability and maintainability, and economic-safety integration, the problems in the original layout such as uneven pipeline conditions and insufficient operating space were solved by optimizing equipment elevation differences, implementing symmetric piping, and consolidating operation platforms. The key points to be considered in the equipment layout of framework, the setting of operation platforms, and the layout of important pipelines are introduced. A reasonable layout of the framework plays a crucial role in ensuring the safety and stability of the plant, reducing the energy consumption and investment, and guaranteeing the catalyst reduction and hydrogenation performance. This provides practical engineering reference for the design of similar trickle-bed hydrogenation reactor frameworks.

 In petrochemical plants, the antivibration design of high-pressure small-bore pipelines are often overlooked, yet vibration issues may compromise the safe and stable operation of the plants. This paper takes a synthetic base oil project (PAO unit) as a case study. By integrating the pulsation and vibration analysis of the inlet/outlet pipelines of high-pressure reciprocating pumps and reciprocating compressor, this article systematically explores the optimized layout strategies, support design, and vibration control measures for high-pressure small-bore pipelines, and proposes systematic troubleshooting procedures for field vibration problems. Through case analysis, effective antivibration strategies are summarized, providing references for the design and vibration mitigation of similar pipelines to enhance the reliability and safety of the plant.

 The residual stress generated during the deep drawing forming process of pressure vessel heads seriously affects the quality of the heads. In order to accurately predict the influence of various process parameters on maximum residual stress, this paper selects blank holding force, friction coefficient and die fillet radius as research variables, and designs a numerical simulation scheme according to the response surface methodology. Abaqus software is used for numerical simulation calculation to obtain the maximum residual stress of the deep-drawing forming head. Design Expert software is used to analyze the numerical simulation test data. The regression equation between the maximum residual stress of the deep drawing forming head and the three variables, namely the response surface mathematical model, is obtained by fitting. According to the response function, the three-dimensional response surface diagram for the influence of interaction between the variables on the maximum residual stress of deep drawing forming head is drawn. The results show that the regression model is highly significant, the fitting precision of the response function is good, and the reliability is high. It verifies that the response surface methodology can accurately analyze and predict the maximum residual stress of the deep drawing forming head, and provides a reference for process parameter optimization and residual stress research of the deep drawing forming process of pressure vessel heads.

The power boiler calculation model constructed in this paper provides an effective tool for chemical enterprises to accurately quantify the impact of coal quality and load on steam production, and provides a reliable basis for fuel procurement and operation optimization. After verifying and optimizing the model using the actual operation data of a 160 ton/h fluidized bed boiler of a chemical company in Shandong, the accuracy and reliability of the model have been significantly improved. It was calculated that the fuel cost per unit of steam was reduced by 7.3%. The boiler efficiency was about 81.25% when using high calorific value coal. By adjusting the operating parameters, the flue gas temperature was reduced by 10°C, the combustible content of ash was reduced to 3.97%, and the boiler efficiency was increased to 83.79%. It has effectively improved the economic benefits and energy utilization efficiency of enterprises, providing a scientific basis and effective means for the operation and management of power boilers in chemical enterprises.

To address the issues of frequent clogging and short operation cycles in the purification unit of styrene extraction plant, this study systematically analyzed the main factors contributing to the blockage in key components of the unit, including process temperature, decolorizing agent concentration, and reaction residence time, based on polymerization reaction mechanisms. Through measures such as optimizing the injection concentration of the decolorizing agent, improving the performance of polymerization inhibitors, and strengthening the control of process parameters, the clogging in the purification system was effectively mitigated. Following the implementation of these optimizations, the continuous operation cycle of the unit has been extended to over two years. This not only maintains the environmental advantage of avoiding the discharge of high-salinity wastewater, but also significantly enhances production stability and economic benefits. The study demonstrates that targeted process adjustments based on polymerization mechanisms are crucial for ensuring the long-term, stable operation of this green decolorization technology.

 As the simplest fully biodegradable plastic with excellent mechanical properties, poly (glycolic acid) (PGA) can be widely used in fields such as healthcare, oil fields and packaging. This article summarizes the characteristics and applications of poly (glycolic acid), and provides a detailed introduction to main production technologies such as one-step method (direct polymerization) and two-step method (ring opening polymerization), especially the synthesis and purification technologies of the key monomer glycolide. The process route of producing poly (glycolic acid) from coal via synthesis gas is explored, and the future direction of industrial development of poly (glycolic acid) is summarized, providing reference for its large-scale industrial application.