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各位有时间，就用“新规范的加氢裂化反应器吨位差很多，总价相差18000万！具体解释一下”提问一下国产大模型，相当于有趣。
国产大模型集体翻车。它们要么听不懂提问，要么找不到这个规范，关键是张口新规范，闭口旧规范，说的头头是道，但就是不知道新规范是啥，旧规范是啥，那你说个JB毛啊
豆包大模型终于给个标准，T/CASME 509-2023《石化工业生产专用设备生产技术要求 加氢反应器》，本质上这个标准是生产技术要求啊。
ChatGPT"深度研究"一番后，写了篇分析。写的是比国产大模型好，引用的是也是美国企业的例子，但是它也没说明新规范的名称。
Technical Analysis of New vs. Old Hydrocracking Reactor Specifications
A recent large-scale hydrocracking reactor (slurry-phase, heavy-feed) was reported at 3,000+ tonnes (“world’s first 3000-ton slurry-bed reactor”)
, far above typical earlier designs. This weight jump has driven a ¥180 million cost increase. The new reactor is ~72 m tall and handles a much higher throughput than the previous unit
. We analyze the specification changes: materials, design pressure/temperature, capacity, dimensions, and construction complexity. Each change is tied to higher steel mass and fabrication work (thus higher cost). Figure 1 (below) illustrates a cutaway of a modern multi-bed hydrocracking reactor with internal trays and support grids
The table summarizes key differences. The new reactor’s shell uses a much higher-grade alloy steel or clad steel, with wall thickness often exceeding 30 cm. For example, one recent ASME-designed reactor (3.96 m dia) used F22 (2.25Cr-1Mo) steel, 12.6875″ thick
. Higher design pressures/temperatures require these thick walls by code. By contrast, older units often used lower-strength steel with thinner walls. Upgrading steel grade and thickness inherently multiplies the vessel mass (steel density ≈ 7.8 ton/m³).
Materials and Design Conditions
Modern hydrocrackers process heavier feeds at higher hydrogen pressures, demanding exotic metallurgy. New reactors typically use alloy steels (Cr–Mo, Ni–Cr) for corrosion and strength
. For instance, the Lavera refinery replaced its 40-year-old hydrocracker with two new 420 t vessels of 2.25Cr–1Mo steel (185 mm thick walls, stainless overlay)
. By contrast, the old units likely used plain carbon steel. Higher Ni/Cr content increases material density (and cost) by ~5–10% over carbon steel, and requires expensive forgings. Cladding or overlay (e.g. stainless on carbon steel) also adds weight. Design conditions have escalated: modern slurry-bed reactors may operate above 150 bar and 450°C. Meeting these requires large safety factors per ASME VIII. For example, a published design had a 12.69″ (32.2 cm) F22 shell at 3.96 m diameter
. Such thick sections are very heavy – roughly 7.8 t/m³ × (shell volume). Even a 4 m-dia × 30 m vessel with 30 cm walls weighs ~~1,000 t. The new specification’s higher pressure and longer run length (to improve conversion) pushed thickness above that, doubling the weight.
Capacity and Physical Dimensions
Higher capacity directly scales vessel size. Hydrocracker throughput is roughly proportional to cross-sectional area and catalyst volume. The new design targets throughput several times larger than the old. For example, a legacy single-train HCU might have handled ~150 kt/yr, whereas modern 3MTPA units (two trains) now integrate 3,000+ t reactors
. To accommodate this, the new vessel’s diameter jumped from the old ~4–5 m to over 6 m
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. Its total height (including shell and internal beds) grew from a few tens of meters to ~70 m or more
. Since volume scales with (diameter)²×height, a 1.5× larger diameter and ~3× taller vessel yields ~6–7× volume. Given similar wall thicknesses, the mass of steel soars accordingly. For instance, the new 6.15 m×70 m reactor (wall 0.32 m thick
) dwarfs a typical 4 m×30 m predecessor. This huge size increase alone explains most of the 1,000+ ton jump. In general, every 10% increase in diameter adds ~21% more area (and weight), and additional height further multiplies it.
Internals and Construction Complexity
New reactors incorporate more elaborate internals to ensure performance with heavy feeds. Unlike older units with simple distributor trays, the new design adds multiple beds, redistributor trays between beds, and quench headers for intermediate cooling
. All these structures – support grids, mixing funnels, collector rings – are typically made of stainless or nickel allo
, adding considerable weight. For example, support grids alone can be fabricated in 316L or 347 SS (density ~8.0 t/m³)
. Each additional tray/beam layer can add several tons. Figure 1 illustrates this: the reactor has three packed catalyst beds, each on a lattice of beams and wedge-wire supports
. Fabrication has become far more complex. In one Chinese project, the reactor “consists of three tubes, with each weighing over 1,000 tons,” requiring two welding teams working in tandem to ensure identical seam conditions
. Such multi-segment construction (versus a single-shell build) is needed because forging a single 3,000 t cylindrical shell is impractical. The welding and assembly itself adds filler metal and requires careful inspection, further increasing material use. Moreover, lifting and aligning these massive sections demanded giant cranes and precise jacking (a 5,200 t hydraulic gantry was used)
. In short, the complexity of putting together thicker, segmented cylinders and heavy internals substantially escalates labor and fabrication costs.
Weight and Cost Implications
Each design change translates to extra tonnes of steel and fabrication. The table above shows that cumulative effects (thicker walls, larger diameter/height, more internals) increase vessel weight by roughly 50–100%. For example, if the old reactor weighed ~1,500 t and the new one ~3,000 t, that is +1,500 t of steel. Even at a baseline material cost of ~￥100–200k/ton for alloy steel, this adds ￥150–300M. In practice, the new reactors use premium alloys (2–4× cost of carbon steel) and massive forgings, so material costs alone can exceed ￥100M. Fabrication premiums (special welding, test, heavy lifts) easily add tens of millions more. In the cited Lavera case, two 420 t reactors cost about €40 million
(~¥300M), implying ≈¥175k/ton. Scaling to a 3,000 t vessel (with more expensive alloys) would roughly approach the ¥180M difference observed. Thus, the weight increase and higher-spec materials account quantitatively for the reported price gap. Each thicker millimeter of wall on a 6 m shell adds ~20 t; each extra support grid adds a few tonnes. The new specification’s sum total of added thickness, diameter, beds and exotic materials drives both the tonnage and the bill of materials dramatically upward.
Conclusion
The new hydrocracking reactor specification departs sharply from the old: it uses higher-grade materials, operates at more severe conditions, and is physically much larger. These changes multiply the steel mass (and fabrication effort) compared to the legacy design. In practice, the tonnage roughly doubled, directly explaining the ~¥180 million price hike. Each factor – materials, design code, capacity, dimensions, and construction complexity – compounds to raise weight and cost (as summarized in the table). This analysis aligns with industry reports of recent high-end reactors (e.g. 3,000+ t units in China) and underscores why even modest specification shifts can yield large budget impacts.
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