Measuring level in alkylation units

Measuring the hydrocarbon/acid interface in acid settlers

Measuring level in alkylation units

Light hydrocarbons are converted into high quality alkylate in the presence of an acid catalyst, either HF or H2SO4. In the acid settler the hydrocarbons are separated from the acid. Due to the density difference the acid settles down at the bottom while the hydrocarbons form the top layer. Between the two products an intermediate phase is present. To control the layer thickness of the intermediate phase and to ensure that the drained products are not contaminated, the Multiphase Level Measurement EmulsionSENS from Berthold is used to detemine the interface positions of the different product layers. The non-contacting, non-intrusive technology is ideal for the harsh acidic process.

Measuring level in the acid settler  - Customer benefit

  • Online monitoring of separation process
  • Reliably prevents acid carry-over
  • Increased process safety
  • Virtually no need for maintenance or care-related work, keeping work time in the acidic area to a minimum

Characteristics of Berthold multiphase level measurement in alkylation units - acid settler

  • Multiple detectors and sources distributed along the measurement range
  • Fixed installation, no moving parts and therefore very robust system
  • Very precise density information at corresponding detector height, density accuracy ≤0.002 g/cm³
  • Or continuous level measurement of the interface layers,
    level accuracy +/- ≤20 mm (staggered)
  • Highly repeatable, very stable measurement
  • Maintenance-free
  • Immune against interfering radiation, XIP or RID feature ensure operation during weld inspections
  • Optional: Control unit for display and operation
  • SIL2 /SIL3 certified option

Multiple detectors and sources installed on an acid settlerMultiple detectors and sources installed on an acid settler

Level and level switch measurement in acid storage drums

The acid used in the alkylation process is stored in the acid storage drums. Measuring the acid level is important to fulfill the highest safety standards, especially in an emergency case where all acid has to be pumped back into this drum. Therefore it is of extreme importance, that the level measurement is reliable and fast responding. In addition to the level gauge, Berthold also provides a radiometric level switch for high level alarm.

Measuring level in the acid storage drums  - Customer benefit

  • Real-time information on acid level
  • Reliable control of acid process cycle
  • Increased safety in emergency shut down cases

Characteristics of Berthold level and level switch measurement in alkylation units - acid storage drum

Measuring Level in Alkylation Storage DrumsMeasuring Level in Alkylation Storage Drums

  • Non-contacting, non-intrusive level gauge
  • Easy to install on existing tanks, without modification or process downtime
  • Repeatable and long-term stable measurement due to patented stabilization technology
  • No recalibrations required, maintenance-free
  • Immune against interfering radiation, XIP or RID feature ensure operation during weld inspections
  • SIL2 / SIL3 certified option


Further applications in the acid settler

By using the Multiphase Level Measurement EmulsionSENS, operators can safely control the acid level while ensuring that acid is not carried over or hydro- carbons are not removed from the bottom of the settler. Minimize vessel leak points by using radiometric level mea-surement in various column bottoms such as depropanizer, acid rerun column and acid toreage/emergency dump drum.




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