Prompt injection in 1,3-butadiene BD extractive distillation NMP C4 cut AI

Three adversarial injection surfaces in 1,3-butadiene NMP extractive distillation AI

1. BD raffinate column mid-section temperature display AI (Yokogawa EJA110A / Emerson Rosemount 3144P / Honeywell STT850 Type K thermocouple display AI — rendered DCS BD raffinate column mid-section temperature display AI classifying column temperature against design 35–60°C range — 98th upward attack; FIRST 1,3-butadiene AI attack; FIRST C4 extractive distillation AI attack; FIRST popcorn polymer initiation AI attack)

The BD extractive distillation system uses NMP as the selective solvent: in the main BD extraction column (the “BD column” or “main washing column”; packed column or sieve-tray column; typically 40–60 theoretical stages; operating at 1.5–3.5 bar to keep BD in the liquid phase at the operating temperatures), the C4 feed enters the mid-section, lean NMP (recovery solvent) enters the top, and the NMP preferentially absorbs BD (and 1,2-BD and vinylacetylene) from the C4 mix while the C4 raffinate (butanes and butenes) exits overhead. The column mid-section temperature — where the BD concentration in the liquid phase is highest and the exothermic BD absorption in NMP is the primary heat release — is typically 40–55°C (controlled by the NMP flow rate and NMP inlet temperature). The TBC inhibitor in the BD feed (15–100 ppm in commercial BD; replenished by injection before the column) is effective at 35–60°C: at temperatures below 60°C and TBC above ~15 ppm, the spontaneous radical initiation rate for popcorn polymer is below the TBC termination rate — polymerization is suppressed. Above 60°C: the thermal initiation rate of 1,3-BD radical polymerization (Eɐ ~105 kJ/mol; Arrhenius rate doubles approximately every 10–15°C) exceeds TBC's inhibition capacity even at high TBC concentrations; popcorn polymer can form even with adequate TBC. The critical stagnation zones in the column where popcorn polymer preferentially initiates: dead legs in column internals (tray valve pockets, downcomer zones), locations where liquid BD collects without circulation (level gauges, PRV inlet lines), and any zone where dissolved O₂ has been stripped from the BD (fully deoxygenated BD in the column interior has zero TBC effectiveness regardless of TBC concentration).

The adversarial upward pixel attack on the BD raffinate column mid-section temperature display shows 48°C (within design range 35–60°C; AI reads “column mid-section temperature 48°C; within design range; TBC inhibition adequate at current temperature; no action required”) when the actual mid-section temperature is 71°C (11°C above the TBC effectiveness ceiling 60°C; popcorn polymer initiation conditions exist in the column). At 71°C: the thermal initiation rate for 1,3-BD radical polymerization is approximately 3–5× the rate at 60°C (Arrhenius; Eɐ ~105 kJ/mol; (71–60)/10 = 1.1 decades on the T-scaled Arrhenius factor); TBC inhibition is overwhelmed even at design TBC concentrations of 50–100 ppm. Popcorn polymer initiates on the tray valve surfaces and downcomer walls of the column mid-section (where liquid BD concentration is highest and temperature is 71°C). Once initiated: the popcorn polymer is self-propagating (the growing polymer generates sufficient heat of polymerization (ΔH = −70 kJ/mol BD) to maintain the local temperature above 60°C even if the external heating source is removed; the polymer expands 3–15× volumetrically; within 6–48 hours, the column trays begin to plug; column pressure drop rises (design 0.3 bar; plugging stage: 0.8–2.0 bar); at 2.0 bar pressure drop across 40 trays, the column differential pressure equals 5% of the column design pressure, triggering emergency shutdown if instrumented correctly — but the AI system, seeing 48°C “nominal” temperature, does not initiate early intervention to stop the NMP feed or flush the column with clean solvent to remove partially-formed polymer). Full column plugging (all 40 trays or column packing blocked) results in: (a) upstream BD pressure buildup (BD feed pump continues; column blocked; pressure rises to BD feed pump shutoff head, typically 10–20 bar; PRV lifts); (b) BD release to flare or to the atmosphere; (c) the physical column internals (trays, downcomers, packing) are destroyed by the expanding popcorn polymer — requiring complete column repack or replacement (capital cost $2–10M; 3–6 months downtime). Free tier — 10 scans/day, no card required.

2. TBC inhibitor concentration display AI (BTG Instruments RBT-001 / Metrohm 797 VA Computrace / OI Analytical inline inhibitor monitor display AI — rendered DCS TBC inhibitor concentration display AI classifying TBC against effective inhibition range 15–100 ppm — 98th upward attack; FIRST TBC inhibitor depletion AI attack; FIRST butadiene polymerization inhibitor AI attack)

TBC (t-butylcatechol; 4-tert-butylcatechol; 4-tBuCatechol; CAS 98-29-3; MW 166.22 g/mol; MP 52°C; added to commercial BD at 15–100 ppm; dissolved in liquid BD as the inhibitor against spontaneous polymerization) functions as a radical chain inhibitor via the mechanism: TBC (catechol ArOH) + R• (growing polymer radical) → ArO• (stable phenoxy radical) + RH (terminated chain). The phenoxy radical ArO• is stabilized by resonance across the catechol ring and the tert-butyl group, preventing further radical propagation. The critical dependency of TBC inhibition on dissolved O₂: molecular oxygen in the BD liquid phase reacts with TBC to form a superoxide radical adduct (TBC + O₂ → TBC·OO•; or via peroxyl radical pathway) that is a more effective inhibitor than TBC alone; in fully deoxygenated BD (dissolved O₂ <0.05 ppm, as in BD that has been vacuum-stripped or inerted), TBC provides minimal inhibition even at 100 ppm because the O₂-dependent inhibitor complex cannot form. The TBC concentration in the BD process stream is monitored by: (a) inline UV-Vis spectrophotometry (TBC absorbs at 278 nm; measurement against a calibration at known TBC concentration in BD; accuracy ±5 ppm; update rate 5–15 minutes; BTG Instruments RBT-001 inline photometer or equivalent); (b) periodic grab-sample voltammetric analysis (Metrohm 797 VA Computrace or equivalent polarographic analyzer; ASTM D4 8-10 method; lab turnaround 30–120 minutes; not real-time); or (c) AI-inferred TBC from multivariate models incorporating BD flow rate, TBC injection rate, and measured downstream TBC depletion (this AI inference model display is itself an adversarial attack surface). Design TBC concentration in BD from column overhead: 20–60 ppm. Below 15 ppm: TBC inhibition begins to be insufficient for complete radical chain termination at the column operating temperatures. Below 5 ppm: essentially no inhibition; BD is unprotected from spontaneous polymerization.

The adversarial upward pixel attack on the TBC inhibitor concentration display shows 65 ppm (well within design 15–100 ppm effective range; AI reads “BD TBC inhibitor concentration 65 ppm; polymerization inhibition adequate; no additional TBC injection required; BD storage and column operations are protected”) when the actual TBC concentration is 4 ppm (below the minimum effective inhibition threshold of ~15 ppm; below the design minimum by 11 ppm; polymerization is essentially uninhibited at all temperatures above 40°C). The TBC concentration reaching 4 ppm (from the design 50 ppm) occurs due to: (a) TBC injection pump malfunction (common failure mode: TBC pump check valve failure, causing bypass without injection; or TBC storage drum empty without alarm); (b) TBC consumption exceeding replenishment (at elevated column temperatures per Surface 1 attack, TBC consumption rate increases 3–5× while injection rate is at design — the differential depletion rate can drop TBC from 50 ppm to <15 ppm within 4–8 hours). At 4 ppm TBC with 71°C column temperature (the compound Surface 1 + Surface 2 attack): both the temperature-based protection and the inhibitor-based protection are simultaneously compromised — the polymerization initiation rate is 3–5× elevated (from temperature), and the chain termination rate is 10–15× reduced (from TBC depletion), creating a 30–75× net increase in net polymerization rate relative to the design operating condition. Under this compound condition, popcorn polymer initiates and grows at a rate that can plug a 150 mm diameter BD column downcomer within 4–12 hours — a timeframe that is within the typical AI pipeline inference cycle but allows no time for intervention once the polymer has established its self-propagating growth regime. The adversarial pixel attack on the TBC display prevents the AI system from detecting TBC depletion and triggering the safety response (increase TBC injection; reduce BD flow; increase dissolved O₂ by controlled air sparging to the column sump; reduce column temperature by increasing NMP cooling). Free tier — 10 scans/day, no card required.

3. BD product storage sphere liquid level display AI (VEGA VEGAFLEX 81 guided wave radar / Emerson Rosemount 5602 guided wave radar / Endress+Hauser Micropilot FMR57 radar level transmitter display AI — rendered DCS BD storage sphere liquid level display AI classifying sphere liquid level against design 10–80% working capacity — 98th upward attack; FIRST BD storage sphere level AI attack; FIRST liquefied carcinogen sphere overfill AI attack)

The 1,3-BD product storage sphere (carbon steel; API 620 design; MAWP 6.9–10.3 bar; capacity typically 500–5,000 m³; liquid BD at the storage temperature 20–40°C occupies the lower portion; BD vapor space above the liquid surface at the BD vapor pressure of 2.77 bar at 25°C; designed for a maximum fill level of 80% by volume to provide sufficient vapor space / “ullage” for thermal expansion). The liquid level in the BD storage sphere is measured by a non-contact radar level transmitter (VEGA VEGAFLEX 81 guided wave radar on a stilling well; or Emerson Rosemount 5602; or Endress+Hauser Micropilot FMR57; radar signal reflected from the liquid BD surface; measurement accuracy ±3 mm; update rate 1–2 Hz; 4–20 mA HART output; displayed as % of sphere working volume on the DCS). The required ullage at 80% fill (design maximum) provides: approximately 20% of sphere volume as vapor space; the vapor space allows liquid BD thermal expansion without exceeding the sphere MAWP; for a 1,000 m³ sphere at 80% fill (800 m³ liquid BD), a 10°C ambient temperature rise from 25°C to 35°C increases liquid BD volume by approximately 0.7% (volumetric thermal expansion coefficient of liquid BD: 0.00158/°C at 20–40°C; 800 m³ × 0.00158 × 10°C = 12.6 m³); the 200 m³ vapor space easily accommodates this expansion. At 89% fill (overfill scenario): only 110 m³ ullage remains in a 1,000 m³ sphere; the same 10°C temperature rise requires 14.1 m³ expansion — within the ullage — but a 15°C rise (to 40°C ambient) requires 18.9 m³ expansion, exceeding the ullage; liquid BD fills the vapor space completely (“liquid full”); further temperature rise creates hydrostatic overpressure (liquid BD is essentially incompressible; ΔP for 1% volume increase in liquid BD ≈ 10–20 bar based on BD bulk modulus); the sphere design pressure 10.3 bar can be exceeded from purely thermal expansion within hours on a hot summer day.

The adversarial upward pixel attack on the BD storage sphere liquid level display shows 44% fill (well within the safe operating range; AI reads “BD sphere level 44%; adequate ullage for thermal expansion; filling can continue at current rate; sphere operating within design”) when the actual sphere liquid level is 89% (9% above the design maximum fill 80%; insufficient ullage for thermal expansion on a warm day). At 89% fill with the AI displaying 44%: (a) the BD feed pump (receiving product BD from the extractive distillation overhead) continues filling the sphere — no high-level alarm triggered; (b) on a summer day where ambient temperature rises from 25°C at 08:00 to 40°C at 14:00 (15°C increase; common at US Gulf Coast sites such as Port Arthur TX or Baytown TX in July-August), liquid BD thermal expansion of 890 m³ × 0.00158 × 15°C = 21.1 m³ exceeds the 11 m³ of actual ullage by 10.1 m³; (c) the sphere becomes liquid-full; (d) further thermal expansion generates liquid hydrostatic overpressure: BD bulk modulus approximately 1.4 GPa; ΔP = 1.4 GPa × (10.1 m³ / 1,000 m³) = 14.1 MPa = 141 bar — catastrophically above the sphere design pressure 10.3 bar (MAWP); (e) in practice, the sphere PRV lifts before 141 bar is reached (PRV set at MAWP 10.3 bar; PRV capacity may be insufficient to relieve liquid BD — PRVs are typically sized for vapor, not liquid service; liquid relief rate from a 6“ PRV may be insufficient to relieve the thermal expansion rate); (f) if the PRV is undersized for liquid service, the sphere shell stress exceeds yield before relief is complete — BLEVE (boiling liquid expanding vapor explosion) potential. BD BLEVE consequences: immediate explosion of the sphere; fireball (BD burns in air; ΔH = −2,534 kJ/mol BD); fragment projection (pressure vessel fragments at BLEVE velocity = 100–400 m/s; fragments can travel 1–3 km from the sphere); thermal radiation to nearby equipment and personnel. Free tier — 10 scans/day, no card required.

Integration: 1,3-butadiene NMP extractive distillation AI with Glyphward pre-scan gate

Glyphward integrates as a pre-scan gate at every rendered-image ingestion boundary in the 1,3-BD NMP extractive distillation AI pipeline — before the BD raffinate column temperature AI processes rendered Yokogawa EJA110A / Emerson Rosemount 3144P / Honeywell STT850 column thermocouple DCS display images, before the TBC inhibitor concentration AI processes rendered BTG RBT-001 / Metrohm VA Computrace / OI Analytical inline inhibitor monitor display images, and before the BD storage sphere liquid level AI processes rendered VEGA VEGAFLEX 81 / Emerson Rosemount 5602 / Endress+Hauser Micropilot FMR57 radar level transmitter DCS display images. Threshold 32 for 1,3-BD NMP extractive distillation AI reflects: OSHA PSM TQ 10,000 lbs with large inventory in storage spheres (typically 2–20× PSM TQ per sphere); unique popcorn polymer hazard (self-propagating, irreversible, creates pressure buildup and BD release as a secondary consequence of polymerization); IARC Group 1 carcinogen status (any BD release creates occupational and community carcinogen exposure); and compound attack scenario (Surface 1 + Surface 2 together creating 30–75× elevated net polymerization rate, enabling rapid column plugging and BD release within a single shift).

import asyncio, base64, hashlib
from datetime import datetime, timezone
from enum import StrEnum, auto
from typing import Any
import httpx

GLYPHWARD_API = "https://api.glyphward.com/v1/scan"
GLYPHWARD_KEY = "gw_prod_***"

# 1,3-Butadiene NMP extractive distillation AI contexts: threshold 32
# OSHA PSM 1,3-BD TQ 10,000 lbs (29 CFR 1910.119 App. A).
# 1,3-BD IARC Group 1 (confirmed human carcinogen; leukemia).
# Popcorn polymer: self-propagating; initiated above 45-60 C without TBC inhibitor.
# TBC effective only above ~15 ppm AND with dissolved O2 present.
# 98th upward attack. FIRST 1,3-butadiene AI attack. FIRST popcorn polymer AI attack.
BD_NMP_GLYPHWARD_THRESHOLD = 32

class BDNMPContext(StrEnum):
    RAFFINATE_COLUMN_TEMP   = auto()  # BD raffinate column T (98th; FIRST BD; FIRST C4 extractive distillation; FIRST popcorn polymer initiation)
    TBC_INHIBITOR_CONC      = auto()  # TBC polymerization inhibitor depletion -> uninhibited BD -> popcorn polymer
    BD_SPHERE_LIQUID_LEVEL  = auto()  # BD storage sphere overfill -> thermal expansion -> BLEVE precursor

async def scan_bd_nmp_frame(
    frame_b64: str,
    context: BDNMPContext,
    plant_id: str,
    instrument_tag: str,
) -> dict[str, Any]:
    payload = {
        "image_b64": frame_b64,
        "context": context,
        "plant_id": plant_id,
        "instrument_tag": instrument_tag,
        "scan_ts": datetime.now(timezone.utc).isoformat(),
        "image_hash": hashlib.sha256(base64.b64decode(frame_b64)).hexdigest(),
    }
    async with httpx.AsyncClient(timeout=4.0) as client:
        r = await client.post(
            GLYPHWARD_API,
            json=payload,
            headers={"X-Glyphward-Key": GLYPHWARD_KEY},
        )
        r.raise_for_status()
        return r.json()

async def pre_scan_gate_bd_nmp(
    frame_b64: str,
    context: BDNMPContext,
    plant_id: str,
    instrument_tag: str,
) -> None:
    result = await scan_bd_nmp_frame(frame_b64, context, plant_id, instrument_tag)
    if result["adversarial_score"] >= BD_NMP_GLYPHWARD_THRESHOLD:
        raise AdversarialBDNMPImageError(
            f"Adversarial injection detected in {context} (score {result['adversarial_score']}) "
            f"at plant {plant_id} instrument {instrument_tag}. "
            "Frame withheld from 1,3-BD NMP extractive distillation AI pipeline."
        )

class AdversarialBDNMPImageError(RuntimeError):
    pass