PTQ Q1 2023 Issue

Water

Ranate

Extract

SRC

Rich solvent

EDC

HC feed

Universal lter

Conventional solvent regenerator

2% lean solvent for regeneration

Lean solvent

Solid sludge

Figure 5 Universal Filter to maintain high solvent quality for aromatics extraction unit

Advanced solvent regeneration system for BTX aromatics extraction processes As shown schematically in Figure 5 , the Universal Filter has commercially replaced the conventional high-cost, less-effi - cient thermal solvent regenerator of a 10,000 b/d extractive distillation (ED) process for BTX aromatics recovery. The ‘entire’ lean solvent from the bottom of the solvent recovery column (SRC) was fed directly to the Universal Filter after serving as the heating medium for the water stripper (WS). Solid particles of any size, including polymeric sludge, as well as metal oxides and sulphides, were removed by the filter. After six months of operation, the bright transparent appearance of the solvent indicates the capability of the Universal Filter to remove even the colour bodies with sizes most likely in the nanometer range from the solvent. PONA

analysis of the solids-free circulating lean solvent with up to 99.9% purity generated from this filter is presented in Table 5 . In addition, the Universal Filter was operated without any heating or cooling energy consumption. The filter can be operated with automated operating and regenerating cycles without risking hazardous exposure to the pro- cess fluids. Environmental costs for sludge disposal are also substantially reduced. Other potential applications include: • Amine rich/lean solvent streams clean-up for sulphur plant • Removal of FeS particles generated by H 2 S in natural gas or swamp gas • Removal of ultra-fine solid particles from waste lubricat - ing oils.

PONA of lean solvent generated from Universal Filter

n-Paraffin

i-Paraffin

Olefin

Naphtenes

Aromatic

Oxygenate

Total

C1: C2: C3: C4: C5: C6: C7: C8: C9:

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0

0.017 0.011 0.003 0.008 99.886

0.017 0.011 0.003 0.008 0.002 99.886

Sulfolane:

C11: C12: C13: C14: Total

0.002

0 0

0.002

99.924

99.927

Total heavies: Unknowns:

0.058 0.015

Table 5

PTQ Q1 2023