• LinkedIn
  • Youtube
  • Mail
e-mail: info@technobell.eu
Technobell Technology
  • Home
  • Company
    • Integrated Solutions
    • Technobell Worldwide
    • Technobell Team
    • Our Values & Stakeholders
    • Job & Careers
    • Brochures
    • Photo & Video Gallery
  • GRP Technologies
    • CFW Technology
    • GRP Tanks
    • GRP Know How
    • GRP Assistance Team
    • GRP Applications
    • GRP Projects & References
  • Chemical Technologies
    • Maleic Anhydride
    • Phthalic Anhydride
    • Plasticizers
    • Unsaturated Polyester Resins
  • UP Resins Production
  • News & Events
  • Contact
  • Search
  • Menu Menu
  • Maleic Anhydride plant

CHEMICAL PROCESS TECHNOLOGIES

MALEIC ANHYDRIDE

The Technobell technology that is used to produce Maleic Anhydride (MA) is based on a well-known catalyst for oxidation of n-butane to form Maleic Anhydride.

Maleic Anhydride molecule

Maleic Anhydride is a highly reactive chemical intermediate with present and potential uses in practically every field of industrial chemistry. It is essential to the production of a multitude of resins and plastics, agricultural chemicals, petroleum product additives, wetting agents and textile chemicals. Its biggest use is in the manufacture of unsaturated polyester resins.

Maleic Anhydride main advantages

MAIN ADVANTAGES OF THE TECHNOBELL’S MALEIC ANHYDRIDE PRODUCTION PROCESS

  • HIGH CONVERSION AND SELECTIVITY
    Operation using Technobell’s double salt zone reactor system and low bulk density catalyst results in high conversion and selectivity, lower hot-spot of the catalyst and extended catalyst life cycle (5+ years).
  • MINIMISED ENERGY NEEDED FOR FEED GAS COMPRESSION
    Energy needed for feed gas compression is minimised (high butane concentration in the feed reaction gas).
  • HIGH YIELD OF MALEIC ANHYDRIDE
    High yield of Maleic Anhydride: up to 101,5 wt% with single salt zone reactor system and up to 104 wt% with double salt zone reactor system.
  • FLEXIBLE OPERATION
    Fixed bed reactor(s) results flexible operation.
  • SPECIAL DESIGN OF STABILITY/ACTIVITY STABILIZER (TMP) DOSING SYSTEM
    Special design of stability/activity stabilizer (TMP) dosing system results in perfect performance of the catalyst, elongating its lifecycle and improving yield, productivity and control of the catalyst operation.
  • CLOSE-TO-ZERO EMISSIONS
    Completely closed special design pastillator system results in close-to-zero emissions and high reduction of powder content in solid product.
Technobell Maleic Anhydride Technology Maleic Anhydride incinerator Maleic Anhydride - pastillator Maleic Anhydride - reactor Maleic Anhydride plant performance improvement

Maleic Anhydride production process

Technobell’s Maleic Anhydride production process system consists of fixed bed reactor(s) with single or double salt layer circulation, continuous gas cooling, continuous product recovery systems by partial condensation and absorption, batch or continuous dehydrating and distillation/refining system and a continuous incinerator unit with steam turbine generator.

PROCESS DIAGRAMS OF TECHNOBELL’S MALEIC ANHYDRIDE TECHNOLOGIES

Technobell’s MAN process oxidation block with Double Salt Zone Reactor

Technobell Double Salt Zone Reactor

Technobell’s MAN process with semi-continuous Aqueous MAN Recovery system

Technobell’s MAN process with semi-continuous Aqueous MAN Recovery system

Technobell’s MAN process with fully-continuous Aqueous MAN Recovery system

Technobell’s MAN process with fully-continuous Aqueous MAN Recovery system

Technobell’s MAN process with fully-continuous Solvent MAN Recovery system

Technobell’s MAN process with fully-continuous Solvent MAN Recovery system

MALEIC ANHYDRIDE PRODUCTION PROCESS DESCRIPTION

Oxidation

Maleic Anhydride is produced by the partial oxidation of butane with air over a vanadium/phosphorus catalyst. Low concentration (PPM range) of stabilizer (SAS) is added to the feed gas stream to stabilize catalyst activity and selectivity. Water (in the form of steam) is also added under some conditions to modify the catalyst performance.

Technobell has in collaboration with one of the world leading catalyst suppliers developed a reactor with double separated eutectic salt mixture circulation system in order to optimize the catalyst performance by enhancing the control and achieving excellent temperature profile in the catalyst tubes resulting in higher conversion and selectivity, and so to achieve better reaction yield and minimize by-product formation.

Technobell_Double Salt Zone Reactor

Technobell Double Salt Zone Reactor

Reaction Chemistry

Main reaction:

Side reactions:

  • Butane thermal oxidation

C4H10 + 6.5 O2 → 4 CO2 + 5 H2O

C4H10 + 4.5 O2 → 4 CO + 5 H2O

  • Minor reactions forming by- products like acetic or acrylic acids

C4H10 + 2.5 O2 → 2 CH3COOH + H2O

C4H10 + 2.5 O2 → 4/3 CH2CHCOOH + 7/3 H2O

Typical temperatures of reaction are between:

  • Reactor (Salt) temperature: 400 – 440°C.
  • Catalyst temperature (Range): 440 – 485°C
Recovery of Maleic Anhydride

Recovery of Maleic Anhydride

Technobell owns several MAN recovery systems. The optimal system depends on the MAN end use, availability and price of local utilities (OPEX), waste treatment facilities, plant capacity (CAPEX):

1. Aqueous technology for recovery of Maleic Anhydride (more economical for smaller plants)

  • Separation

Cooled reactor off-gas containing MAN is routed to partial condenser where at least half of the MAN is condensed while the rest is fed to the scrubber and forms a maleic acid solution by reaction with boiler feed water (BFW).

  • Recovery system

The condensed MAN (i.e. crude MAN) and the maleic acid solution are then fed to a dehydrating-refining section where xylene is used to form an azeotrope which initiates the dehydration of Maleic Acid.

Technobell’s MAN process with semi-continuous Aqueous MAN Recovery system

Technobell’s MAN process with semi-continuous Aqueous MAN Recovery system

If the plant has high capacity, a continuous dehydrating and refining systems is recommended.

Technobell’s MAN process with fully-continuous Aqueous MAN Recovery system

Technobell’s MAN process with fully-continuous Aqueous MAN Recovery system

2. Solvent based MAN recovery technology 

Solvent-based MAN recovery technology is economical for large scale units, offers a higher product quality at a higher investment cost (CAPEX) but with reduced operation cost (OPEX). Technobell’s fully continuous solvent-based MAN recovery and purification technology uses a phthalate-based solvent agent. Application of this recovery technology together with implementation of Double Salt Zone Reactor results in very high MAN yield and product purity, a close-to-zero plant emission with very low solvent losses resulting in overall market leading OPEX.

Technobell’s MAN process with fully-continuous Solvent MAN Recovery system

Technobell’s MAN process with fully-continuous Solvent MAN Recovery system

Off-gas treatment

Off-gas treatment

The off-gas leaving the top of the scrubber contains not reacted n-butane and other flammable and environmental polluter materials. The valuable n-butane can be partly used again as feed to the reactor by installing an off-gas recycling system or the whole amount of off-gas can be eliminated by burning away its flammable components while the generated heat can be used for steam generation.

Recovered heat of the exothermic reaction and back-cooling of the reaction gases are used for steam generation. In case of requirement, the system can produce high pressure (HHP) steam, which can be used for operation of the air compressor steam-turbine driver(s) or to generate electric energy.

As an option Technobell has a system for valuable n-butane recovery as it can be partly used again as feed to the reactor by installing an off-gas recycling system.

Solid MA production unit

Solid Maleic Anhydride production unit

This part of the plant contains 1-4 Pastillator(s) depending on the required capacity. Each Pastillator has a capacity of max. 12,500 MTPA solid Maleic Anhydride production.  Pastillators are equipped with several trays internally, which are cooled with cold water generated in a refrigerator unit. Molten Maleic Anhydride drops onto the surface of trays and forms solid Maleic Anhydride pastilles immediately on the cold surface. Solid pastilles are removed from the trays by knifes and collected in a bin.

An automatic packing system is weighing and dosing the pastilles into 25 kg plastic sacks, then forms 1 ton of palettes to be ready for supply out the final Maleic Anhydride product.

PROCESS VALUES

Process values

PropertiesUnitExpected Value Solvent RecoveryExpected Value Aqueus Recovery
Colour in molten formHazen5 – 1010 – 15
Melting point°C52,7 – 52,852,6 – 52,7
Maleic Anhydride Puritywt. %99,85 – 99,999,6 – 99,7
Maleic Acid Contentwt. %0,05 – 0,100,05 – 0,15
Colour Stability (150 °C; 1,5 hours)wt. %30 – 4040 – 50

SINGLE/DOUBLE SALT ZONE REACTOR EXPECTED REACTION PERFORMANCE

Expected reaction performance

PROCESS PARAMETER:UNITSINGLE SALT ZONE REACTORDOUBLE SALT ZONE REACTOR
n-C4 concentration in feed gasmol %Up to 2,0Up to 2,2
Conversionmol %82 – 8586 – 90
Selectivitymol %67 – 7267 – 73
Cumulative MA reaction yield* after 5 years of operationwt %99 – 100102
Salt temperature°C405 – 435400 – 445
Catalyst lifecyclemonth48 – 6060 – 72

*ton of crude Maleic Anhydride / ton of feed n-butane in percentage.

Maleic Anhydride plant layout

Technobell Maleic Anhydride Technology

Contact our Chemical Process Technologies Team for more information

SEND INQUIRY

CHEMICAL PROCESS TECHNOLOGIES

  • Chemical Process Technologies
  • Maleic Anhydride
  • Phthalic Anhydride
  • Plasticizers
  • Unsaturated Polyester Resins

PHOTO & VIDEO GALLERY

OUR BROCHURES

CONTACT US

SUBSCRIBE TO NEWSLETTER

FOLLOW US

BUSINESS AREAS

GRP PIPES PRODUCTION TECHNOLOGIES

CHEMICAL PROCESS TECHNOLOGIES

UP RESINS PRODUCTION

PRIVACY POLICY

FOLLOW US

 

www.technobell.si

www.technobell.cn

Contacts

  TECHNOBELL d.o.o. KOPER
Ferrarska ulica 10
6000 Koper, SLOVENIA

+386 5 63 98 276

info@technobell.eu

 

  TECHNOBELL LTD
201, Cervantes House
5-9 Headstone Road
Harrow HA1 1PD
Middlesex, UK

+44 79 000 80 990

info@technobell.eu

Contact Us

SUBSCRIBE TO NEWSLETTER

© 2017-2020 | TECHNOBELL TECHNOLOGY
  • Home
  • Company
  • GRP Technologies
  • Chemical Technologies
  • UP Resins Production
  • News & Events
  • Contact
Scroll to top

We are using cookies to give you the best experience on our website.

You can find out more about which cookies we are using or switch them off in settings.

Technobell Technology
Privacy Overview

This website uses cookies so that we can provide you with the best user experience possible. Cookie information is stored in your browser and performs functions such as recognising you when you return to our website and helping our team to understand which sections of the website you find most interesting and useful.

You can adjust all of your cookie settings by navigating the tabs on the left hand side.

You can read about our cookies and privacy settings in detail in our Privacy Policy.

Strictly Necessary Cookies

Strictly Necessary Cookie should be enabled at all times so that we can save your preferences for cookie settings.

If you disable this cookie, we will not be able to save your preferences. This means that every time you visit this website you will need to enable or disable cookies again.

Google Analytics Cookies

This website uses Google Analytics to collect anonymous information such as the number of visitors to the site, and the most popular pages. 

Name of CookiePurposeExpiration time
_gatUsed to throttle request rate.1 minute
_gaUsed to distinguish users.2 years
_gidUsed to distinguish users.24 hours

Keeping this cookie enabled helps us to improve our website.

Please enable Strictly Necessary Cookies first so that we can save your preferences!