Jacob Clement Nielsen, 12/05/16, Haldor Topsoe A/S

Transcription

1 Jacob Clement Nielsen, 12/05/16, Haldor Topsoe A/S

2 } CATOX Unit design } Catalyst design } Advantages using Catalytic oxidation } Industrial references 5555

3 } When we say catalytic oxidation, it means: Full oxidation, i.e. to the highest possible oxidation number: C x H y + O 2 CO 2 + H 2 O -which is similar to a typical high-t combustion } Although catalytic oxidation also could mean: CH 3 CH 2 OH + O 2 CH 3 COOH + H 2 O

4 Catalytic combustion processes from Haldor Topsoe CATOX (90% of our references) REGENOX (10% of our references)

5 Active phase Pore structure 0, m = 1Å 0, m = 1nm Catalyst from 0,001m = 1mm Reactor 1m 5555

6 C x H y + O 2 CO 2 + H 2 O 1. Step 2. Step 3. Step 4. Step 5. Step Gas phase transport and pore diffusion of reactants Adsorption of reactants Surface reaction Desorption of products Gas phase transport and pore diffusion of products Reactant Products + +

7 Concept of rate determining step Surface reaction regime C o n v e r s io n ( % ) Kinetic limitation - diffusion faster than reaction rate Diffusion regime Reaction rate faster than the diffusion Temperature ( o C)

8 The optimal inlet temperature to the CATOX thus depends on the VOCs and the catalyst type. The inlet temperature is a design parameter! C o n v e rs io n (% ) Carbon monoxide Methanol Toluene Chlorobenzene n-hexane Ammonia Temperature ( o C)

9 Lifetime of catalysts can strongly vary between 2 to 10 years Depends on Load and combination of poisons and inhibitors Thermal load The acceptance of poisons is determined by Catalyst type Catalyst volume

10 } End-users in the petrochemical area, both direct contact and through licensors Engineering packages for large projects (typically PTA, MA, Acrylics etc) Tank farm off-gas projects for Compact CATOX Units } End-users in metal coating and lacquering industry Both small and large scale projects (eg. automotive paintshops, aluminium can printing etc) } End-users in offset printing industry Mainly Standard Compact CATOX } Gas purification, both directly to endusers and through system suppliers CO 2 purification (Linde Gas, Airliquide, Praxair etc.) } Low concentration sulfur removal/gas sweetening (SMC+scrubber solution) Typically large sized projects

11 Saving energy (operating T: ºF) Minimizing CO 2 (carbon dioxide) emmision Normal carbon steel can be used as construction material (below 930ºF) No secondary pollutants such as NOx (nitrogen oxides) and CO (carbon monoxide) Quick start up time Generally more compact plant design Lighter plant Longer lifetime (+20 years) due to lower operating T Can be controlled with low excess O 2 (oxygen) High VOC conversion can be reached > 99% CatalyticOxidation Lower or no support fuel consumption. Autothermal at 0.7 g/nm 3 VOC (REGENOX) and 3.0 g/nm 3 VOC (CATOX) Catalyst can be poisoned Pressure drop over the catalyst bed Thermal Combustion High energy consumption (operating T: 1600ºF) Higher CO 2 (carbon dioxide) emission Stainless steel and/or brick lining needed due to high operating temperature (above 1500ºF) Production of NOx and CO due to high operating T Longer start-up time due to T and heat capacity Generally needs larger reactor design Heavier plant due to brick/ceramic insulation Shorter lifetime (+10 years) due to higher operating T Needs min. 10% surplus O 2 (oxygen) in the gas Typically VOC conversion of 98% Higher support fuel consumption No risk of poisoning Lower pressure drop in the reactor

12 } A Chinese customer runs a plant for producing PTA (purified terephtalic acid) with 600,000 Mtons per year capacity. } The high pressure PTA flue gas contains pollutants such as solvents, carbon monoxide, methyl acetate and methyl bromide. } Haldor Topsoe was asked to improve VOC abatement catalyst design and got the catalyst order for the PTA Plant which consisted of an existing production line 1 (346,000 Nm³/h) and a second line (396,000 Nm³/h) with commission in

13 } Line 1 has been running since July 2013 } We guaranteed: MeBr conversion > 95% VOC conversion > 99% } Performance test by 3 rd party, CTI in China November 2013: MeBr conversion > 99.5% VOC conversion > 99.7% 5555

14 } CATOX is a well proven technology for VOC abatement } Cheaper solution than Thermal oxidation } No secondary pollutants (NOx and CO)

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