Application: Process to produce finished lube-base oils and special oils.
Feeds: Dewaxed solvent or hydrogen-refined lube stocks or raw vacuum distillates for lubricating oils ranging from spindle oil to machine oil and bright stock.
Products: Finished lube oils (base grades or intermediate lube oils) and special oils with specified color, thermal and oxidation stability.
Description: Feedstock is fed together with make-up and recycle hy-drogen over a fixed-bed catalyst at moderate temperature and pressure.
The treated oil is separated from unreacted hydrogen, which is recycled.
Very high yields product are obtained.
For lube-oil hydrofinishing, the catalytic hydrogenation process is operated at medium hydrogen pressure, moderate temperature and low hydrogen consumption. The catalyst is easily regenerated with steam and air.
Operating pressures for hydrogen-finishing processes range from 25 to 80 bar. The higher-pressure range enables greater flexibility with regard to base-stock source and product qualities. Oil color and thermal stability depend on treating severity. Hydrogen consumption depends on the feed stock and desired product quality.
Utility requirements (typical, Middle East crude), units per m3 of feed:
Electricity, kWh 15
Steam, MP, kg 25
Steam, LP, kg 45
Fuel oil, kg 3
Water, cooling, m3 10
Installation: Numerous installations using the Uhde (Edeleanu) propri-etary technology are in operation worldwide. The most recent reference is a complete lube-oil production facility licensed to the state of Turk-menistan.
Licensor: Uhde GmbH contAct
Reactor
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Hydrogen
Application: Hydrogen production with low/no export steam produc-tion from hydrocarbon feedstocks, such as natural gas, LPG, butane, naphtha, refinery offgases, etc., using the Haldor Topsøe radiant-wall Topsøe Bayonet Reformer (TBR). Plant capacities range from 5,000 Nm3/h to more than 170,000 Nm3/h hydrogen (150+ MMscfd H2) and hydrogen purity of up to 99.999+%
Description: The Haldor Topsøe TBR-based hydrogen plant is developed for low export-steam hydrogen production and is tailor-made to suit the customer’s needs with respect to feedstock flexibility and economics. A typical plant comprises feedstock desulfurization, preforming, TBR re-forming, shift reaction and pressure swing adsorption (PSA) purification to obtain product grade hydrogen. PSA offgas is used as fuel in the TBR reformer. Excess heat in the plant is efficiently used for process heating and steam generation.
A unique feature of the TBR is high thermal efficiency. Sensible heat in the process gas is recycled to the steam reforming reaction in the bayonet tube. The high thermal efficiency is utilized to design an energy efficient plant and reduce the size of the radiant-wall reformer.
Economics: TBR-based hydrogen plants provide the customer with a low investment cost and low operating expenses for hydrogen produc-tion when steam has low value. A hydrocarbon consumpproduc-tion of down to 3.28 Gcal/1,000 Nm3 hydrogen (348 MMBtu/scf H2) is achieved de-pending on capacity and feedstock.
References: Heseler-Carstensen, J., “Additional hydrogen capacity by heat exchange reforming” NPRA, May 2010.
Licensor: Haldor Topsøe A/S contact
Bayonet reformer Prereformer
S-removal
Feed Stack
Combustion air Fuel
Shift PSA
H2
Copyright © 2011 Gulf Publishing Company. All rights reserved.
Hydrogen
Application: Production of high-purity hydrogen (H2) from hydrocarbon (HC) feedstocks, using the steam reforming process.
Feedstocks: Ranging from natural gas, LPG to naphtha as well as poten-tial refinery offgases (ROG). Several modern hydrogen plants designed by TECHNIP have multiple feedstock flexibility.
Description: The generic flowsheet consists of feed pre-treatment, pre-reforming (optional), steam-HC reforming, shift conversion and hydrogen purification by pressure swing adsorption (PSA). However, it is often tailored to satisfy specific requirements.
Feed pre-treatment normally involves catalytic removal of sulfur, chlorine and other contaminants detrimental to downstream catalysts.
The treated feed gas mixed with process steam is sent to the fired steam reformer (or adiabatic pre-reformer upstream when applied) af-ter necessary superheating.
The net reforming reaction is strongly endothermic and the heat is supplied externally by combustion of PSA purge gas, supplemented by make-up fuel in multiple burners in a top-fired reformer. Reform-ing severity is optimized for each specific case mainly in terms of S/C ratio and outlet temperature. The reformer effluent is essentially an equilibrium mixture and is cooled though HP-steam generation in the PG boiler before going for shift conversion, where a major portion of carbon monoxide (CO) further converts to hydrogen.
The heat recovery fom the flugas exiting the firebox is achieved in the convection section (vertical or horizontal) and its configuration largely impacts the amount of export steam.
The process condensate resulting from heat recovery and cooling is separated and generally re-utilized in the steam system after neces-sary treatment. The entire steam generation is usually on natural cir-culation, which adds to high reliability. The cooled process gas flows to the PSA unit that provides high-purity hydrogen product (typically
< 10 ppmv total carbon oxides and in some cases < 1ppmv CO).
Typical specific energy consumptions based on feed + fuel – ex-port steam range between 3 to 3.4 Gcal/KNm3 (320 to 360 Btu/scf) LHV, depending upon the feedstock, plant capacity and heat recovery optimization. Recent advances include high-purity export steam, gas turbine integration for steam-power synergy, environmental perfor-mance and recuperative reforming for capacity retrofit, thus lowering the hydrogen plant C-footprint.
Installation: TECHNIP, maintaining a leading market share, has de-signed over 260 hydrogen plants worldwide covering a wide range of capacities ranging from 12 to 530 tpd (5–220 MMscfd). Most of these installations are for refinery application with basic features for high reliability (99.5%+ excluding forced outage) as well as optimized efficiency and installed cost.
Licensor: TECHNIP contact
Pre-reformer
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Hydrogen
Application: Production of hydrogen for refinery applications and petro-chemical and other industrial uses.
Feed: Natural gas, refinery offgases, LPG, naphtha or mixtures thereof or any other feedstocks.
Product: High-purity hydrogen (typically >99.9%), CO, CO2, HP steam and/or electricity may be produced as separate creditable byproduct.
Description: The plant generally comprises four process units. The feed is desulfurized, mixed with steam and converted to synthesis gas in steam reformer over a nickel containing catalyst at 20 – 40 bar pressure and outlet temperatures of typically 860°C– 890°C for hydrogen production.
The synthesis gas is further treated in the adiabatic carbon monoxide (CO) shift and the pressure swing adsorption unit to obtain high-purity hydrogen. Process options include feed evaporation, adiabatic feed pre-reforming and/or HT/LT shift to process, e.g., heavier feeds and/or opti-mize feed/fuel consumption and steam production.
Uhde’s design enables maximizing process heat recovery and opti-mizing energy efficiency with operational safety and reliability. The Uhde’s steam reformer features a well-proven top-fired design with tubes made of centrifugally cast alloy steel and a unique proprietary “cold” outlet manifold system for enhanced reliability. AA special feature further spe-ciality is Uhde’s bi-sectional steam system for the environment-friendly full recovery of process condensate and production of contaminant-free high-pressure export steam (3) with a proven process gas cooler design.
The Uhde steam reformer concept also includes a modularized shop-tested convection bank to maximize plant quality and minimize construction risks. Uhde usually offers tailor-made designs based on ei-ther their own or the customer’s design standards. The hydrogen plant is often fully integrated into the refinery, particularly with respect to
steam production and use of refinery waste gases. Uhde has extensive experience and expertise in the construction of highly reliable reformers with hydrogen capacities of up to 220,000 Nm3/ h (197 MMscfd). Re-cent developments include the reduction of CO2-emissions while using removed CO2 for sequestration or enhanced oil recovery (EOR).
Economics: Depending on the individual plant concept, the typical con-sumption figure for natural gas based plants (feed + fuel – steam) may be as low as 3.05 Gcal /1,000 Nm3 (324 MMBtu/ MMscf).
Installation: Uhde is currently executing several designs for hydrogen plants. These include a 150,000 Nm³/134 MMscfd plant for Shell in Canada and a 91,000 Nm³/h/81 MMscfd plant for Bayernoil in
Ger-Steam export
emissions.
References: Ruthardt, K. and M. Smith, “Reliability and availability,”
Hydrocarbon Engineering, February 2008.
Ruthardt, K., K. R. Radtke and J. Larsen, “Hydrogen trends,”
Hydrocarbon Engineering, November 2005, pp. 41– 45.
Michel, M., “Design and Engineering Experience with Large-Scale Hydrogen Plants,” Oil Gas European Magazine, Vol. 30 (2004) No. 2 in:
Erdöl Erdgas Kohle Vol. 120 (2004) No. 6, pp. OG 85–88.
Licensor: Uhde GmbH contAct
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