|
China Resid Oil Reactor Manufacturer
China resid oil reactor manufacturer
,heat exchanger for resid oil
,industrial resid oil reactor
China Resid Oil Reactor Manufacturer
What does a resid oil reactor from Shijiazhuang Zhengzhong Technology Co., Ltd provide to refiners? Shijiazhuang Zhengzhong Technology Co., Ltd (Center Enamel) builds resid oil processing reactors that upgrade atmospheric and vacuum bottoms, the heaviest refinery streams carrying up to 400 ppm nickel and vanadium and conradson carbon up to 25 percent. The portfolio includes ebullated-bed reactors (H-Oil, LC-Fining style) at 5 to 20 MPa and 400 to 450°C, fixed-bed resid hydrotreaters at 10 to 18 MPa, slurry-phase hydrocracking, and coking drums, all engineered for demetallization, erosion resistance and long run length between turnarounds.
1. Resid Processing Routes
Four routes handle resid, differentiated by how much metals and coke they tolerate:
- Fixed-Bed Resid Hydrotreater: Vacuum resid flows down through graded catalyst beds at 10 to 18 MPa and 380 to 420°C, removing sulfur, metals and conradson carbon from the top down. Because metals deposit on the top layer, the bed is loaded with cheap guard material over active catalyst and the reactor is switched or topped up at the first sign of breakthrough. It gives high-quality upgrade but is limited by the metals the feed carries, since a high-metal resid plugs the top of the bed quickly.
- Ebullated-Bed Hydroconversion: A three-phase (oil, gas, catalyst) bed is suspended by upward liquid flow at 5 to 20 MPa and 400 to 450°C, with catalyst continuously added and withdrawn so the bed stays active despite high metals. This is the route for the dirtiest feeds, tolerating 400 ppm metals and 25 percent conradson carbon, because the moving catalyst carries the deactivation away instead of plugging the top. The reactor must contain an internal distributor that keeps the bed expanded and well mixed without short-circuiting.
- Slurry-Phase Hydrocracking: Resid is reacted as a slurry with a dispersed or suspended catalyst at 420 to 460°C and 15 to 24 MPa, converting almost all of the heavy fraction to distillate and rejecting metals and coke in a bottoms stream. It accepts the widest feed range of any route and maximizes conversion, but the reactor and downstream separator must handle a solids-laden slurry and extreme erosion, so material and velocity limits dominate the mechanical design.
- Resid Fluid Catalytic Cracking and Coking: Resid is cracked in an RFCC unit at 500 to 550°C or coked at 480 to 510°C to recover light products, with the metals ending in the catalyst or coke. These routes need no hydrogen but produce the most coke and the dirtiest byproduct, and the reactor or drum must survive thermal cycling and abrasion. They are chosen when hydrogen is unavailable or when maximum light-product recovery from the very bottom of the barrel is the goal.
2. Engineering Resid Reactors for Metals and Coke
Resid is the most abusive feed in refining. Four engineering responses apply:
- Demetallization and Graded Loading: Nickel and vanadium deposit on catalyst and foul surfaces, so fixed-bed units use a graded top layer of low-cost guard material that captures metals before the active bed, and ebullated units add fresh catalyst daily at 0.5 to 2 percent of inventory to hold activity. The reactor internals distribute flow so deposition is even, because uneven metals laydown channels the flow and fails the bed early. Metals handling, not kinetics, sets the run length of a resid unit.
- Erosion and Velocity Control: Resid and slurry streams carry gritty solids that erode elbows, distributors and separators. The design limits local velocity, uses erosion-resistant overlays or hard-faced trims at the worst locations, and avoids dead spots where solids settle and abrade. In slurry-phase service the separator and the bottoms line see the worst wear and are specified with generous corrosion and erosion allowances plus inspection access, because a penetrant leak here is both a loss and a fire risk.
- Hot-Wall Cladding for Hydrogen Service: Where resid hydroconversion runs in hydrogen, the shell is a hot-wall clad vessel with 347SS or 316L overlay over SA-387, sized inside the Nelson curve for the temperature and hydrogen partial pressure exactly as for hydrocracking. The overlay must survive not only hydrogen but also the abrasive resid and the thermal cycles, so bond and dilution are examined by ultrasonics and the dilution kept low enough to meet the surface chemistry requirement.
- Run-Length and Turnaround Design: Resid reactors are designed for the interval between turnarounds, typically 6 to 24 months, not just for start-up. That means the internals, the cladding and the refractory are qualified for the full cyclic and abrasive duty, with access for in-situ cleaning and inspection, and the catalyst handling system sized for the planned addition or change-out. A resid reactor that reaches spec but cannot be turned around safely on schedule is a poor investment.
Resid Processing Reactor Comparison Matrix
| Route | Metals Tolerance | Pressure | Dominant Design Response |
|---|---|---|---|
| Fixed-bed hydrotreater | Low to moderate | 10 to 18 MPa | Graded bed, guard layer |
| Ebullated bed | Up to 400 ppm | 5 to 20 MPa | Circulating catalyst, distributor |
| Slurry phase | Very high | 15 to 24 MPa | Erosion control, solids handling |
| RFCC or coking | High, to coke | Near atmospheric | Thermal cycle, abrasion |
Frequently Asked Questions (FAQ)
Q: What is the difference between fixed-bed and ebullated-bed resid hydroconversion?
A: A fixed-bed resid hydrotreater flows feed down through graded catalyst at 10 to 18 MPa, capturing metals on a guard layer at the top, and is limited by how much metals the feed carries before the bed plugs. An ebullated-bed reactor suspends the catalyst in upward liquid flow at 5 to 20 MPa and continuously adds and withdraws catalyst, so it tolerates up to 400 ppm metals and 25 percent conradson carbon because deactivation is carried away rather than accumulated at the top. Fixed bed gives higher quality at lower metals; ebullated bed handles the dirtiest feeds and runs longer between full change-outs.
Q: Why does resid cause erosion in reactors?
A: Resid and slurry-phase streams carry gritty solids, fine catalyst, coke and scale that abrade metal at high velocity, especially at elbows, distributors and separators. Erosion thins walls and trims until they leak, and in hydrogen service a leak is catastrophic. The design limits local velocity, applies erosion-resistant overlays or hard-faced trims at the worst locations, and avoids dead spots where solids settle and grind. In slurry-phase service the separator and the bottoms line see the worst wear and are given generous allowances plus inspection access.
Q: How are metals removed in resid upgrading?
A: Metals are removed by deposition on the catalyst, not by chemistry that destroys them. Fixed-bed units use a graded top layer of low-cost guard material that captures nickel and vanadium before the active bed, and the reactor is topped up or switched at breakthrough. Ebullated-bed units add fresh catalyst daily at 0.5 to 2 percent of inventory so the bed stays active despite continuous metals laydown. The metals end in the spent catalyst or coke, which is then handled as a containing waste or recovered, never released to the product.
Q: What should a buyer verify for a resid reactor?
A: Four checks. Feed matching: confirm the route tolerates the actual metals and conradson carbon of the resid, not a generic grade. Hydrogen service: for hydroconversion require a hot-wall clad vessel inside the Nelson curve with ultrasonic examination of the overlay. Erosion: review the velocity limits and the hard-facing at distributors and separators. Life-cycle: require the catalyst handling and turnaround provisions, the cladding and refractory inspection access, and the delivered file with material certificates, welding procedure qualifications, the hydrostatic test at 1.3 times design pressure, and the run-length basis stated.
