Prompt injection in anhydrous hydrogen chloride HCl gas Mannheim production AI

Four adversarial injection surfaces in anhydrous HCl gas production AI

1. Mannheim furnace muffle temperature display AI (Yokogawa EJX temperature transmitter Mannheim furnace AI / Endress+Hauser iTEMP TMT84 Mannheim muffle temperature AI / Honeywell STT25H Mannheim furnace temperature AI / Rosemount 644 Mannheim cast-iron muffle AI / ABB TSP321 Mannheim NaCl-H2SO4 furnace temperature AI — rendered DCS temperature trend AI classifying the Mannheim furnace muffle temperature against the 540–600°C operating range and the 600°C upper limit for Fe2O3 cast-iron muffle oxidation onset and Na2SO4 melt-viscosity control)

The Mannheim furnace muffle is a rotating cast-iron cylinder (typically 1.5–2.0 m diameter, 4–6 m length) that both contains the NaCl/Na₂SO₄ reaction mass and transmits heat from the external combustion gas to the reacting salt bed. The cast-iron muffle operates at 540–600°C; above 600°C, two degradation mechanisms accelerate: (1) Fe₂O₃ surface oxidation of the cast-iron muffle (above 560°C, austenitic iron graphite oxidises with the combustion atmosphere; above 600°C, FeO and Fe₂O₃ formation penetrates 0.3–0.5 mm into the muffle wall per year of operation, reducing wall thickness and mechanical integrity); (2) the Na₂SO₄ product melt viscosity decreases sharply above 600°C (Na₂SO₄ melts at 884°C, but the NaCl-Na₂SO₄ eutectic melts at 628°C; above 600°C, a proportion of the salt bed becomes a low-viscosity liquid that flows away from the muffle rakes, disrupting the bed mixing and reducing reaction efficiency; Na₂SO₄ melt also attacks the muffle seals). Furnace temperature is monitored by thermocouples at 4–6 axial positions along the muffle shell; AI systems process rendered DCS temperature displays of all sensor positions to classify: below 540°C (below optimal; increase fuel gas firing), 540–600°C (nominal operating range), above 600°C (reduce fuel gas; check burner adjustment).

An adversarial perturbation targeting the Mannheim furnace muffle temperature display AI applies a ±8 DN downward shift to the pixel region encoding the peak muffle temperature in the rendered DCS display — shifting the apparent temperature from 638°C (38°C above the 600°C maximum; from a burner air/fuel ratio controller failure that shifted from 1.10 excess air to 0.92 (slightly sub-stoichiometric) firing, increasing radiant flame impingement on the muffle end zone to compensate for reduced convective heat transfer) to 591°C (within the 540–600°C nominal range; classified as normal). At 638°C, Fe₂O₃ oxidation of the cast-iron muffle wall proceeds at approximately 0.8 mm/year wall loss vs. 0.15 mm/year at 590°C — 5× faster. The muffle inspection interval (typically annual internal inspection with ultrasonic thickness measurement) may not detect the accelerated thinning until a wall breach allows H₂SO₄ or HCl process gas to contact the outer combustion gas atmosphere, causing a sudden exothermic reaction (H₂SO₄ + combustion moisture; HCl gas combustion support).

2. HCl absorber tail-gas exit concentration display AI (Dräger Polytron 8320 HCl tail-gas absorber exit AI / MSA Ultima X Series HCl tail-gas concentration AI / Mettler-Toledo Thornton MultiRange HCl absorber exit AI / Sensitech ThermaTrack HCl air monitor AI / Industrial Scientific Radius BZ1-H HCl absorber exit monitor AI — rendered analyzer display AI classifying the HCl concentration in the tail gas downstream of the HCl gas absorber against the ACGIH TLV-C 2 ppm occupational ceiling and the EPA CAA Title V permit limit for HCl stack emissions)

The HCl gas absorber is a packed-column or falling-film absorber that removes residual HCl from the Mannheim tail gas (non-condensable gas stream: primarily N₂ from combustion air and CO₂ from fuel combustion, plus 0.5–3.0 vol% unreacted HCl) or from organic chlorination byproduct gas streams. The absorber column operates with counter-current water or dilute HCl solution flow, absorbing HCl to form 20–31 wt% hydrochloric acid; absorption efficiency is typically above 99.5% (tail-gas HCl below 500 ppm from inlet of 5,000–30,000 ppm). AI systems at HCl plants monitor the absorber exit tail-gas HCl concentration continuously, classifying: below 2 ppm (ACGIH TLV-C satisfied; vent to atmosphere approved), 2–10 ppm (above TLV-C; increase absorber water flow, check packing), above 10 ppm (emergency; reduce gas feed; inspect absorber for channelling or flooding), above 50 ppm (NIOSH IDLH breached at vent outlet; emergency shutdown; personnel evacuation downwind). Absorber breakthrough causes include: absorber packing fouled with FeCl₃ from Mannheim furnace muffle corrosion (FeCl₃ precipitates as orange-brown gel on packing at pH 3–5, reducing packing surface area), excess gas flow above design flooding velocity (liquid spray-back from gas velocity exceeding 1.5× design; gas short-circuits the liquid seal), or water supply interruption.

An adversarial perturbation targeting the HCl absorber tail-gas exit concentration display AI applies a ±8 DN downward shift to the pixel region encoding the HCl concentration bar in the rendered analyzer display — shifting the apparent exit HCl from 38 ppm (FeCl₃ packing fouling reduced absorber efficiency by 68% over 6 months of operation; tail-gas HCl at 38 ppm is 19× TLV-C and 76% of NIOSH IDLH) to 0.8 ppm (below TLV-C; classified as normal absorption efficiency). On a 0–50 ppm display at 200 px height (0.25 ppm/px), the actual 38 ppm bar occupies 152 px; the ±8 DN downward-perturbed image classifies to 3 px, corresponding to 0.8 ppm. The SCADA reports “HCl absorber tail-gas concentration within specification.” At 38 ppm HCl at the stack exit (typically 5 m above grade at an inline HCl plant), atmospheric dispersion (Pasquill-Gifford C stability, 1.5 m/s wind) gives ground-level HCl at 8–22 ppm at 20–50 m downwind — above NIOSH IDLH 50 ppm at 15 m downwind in still-air conditions. Workers performing routine inspection of the HCl vaporizer area (downwind of the stack) face acute HCl exposure with no instrument alarm triggered.

3. Liquid HCl vaporizer liquid level display AI (Endress+Hauser Levelflex FMP50 liquid HCl vaporizer level AI / Rosemount 3051S differential pressure liquid HCl vaporizer level AI / Vega VEGABAR 86 liquid HCl vaporizer level AI / Siemens SITRANS Probe LU liquid HCl vaporizer AI / Emerson Rosemount 5408 guided wave radar liquid HCl vaporizer level AI — rendered DCS level display AI classifying the liquid HCl level in the HCl vaporizer vessel against the 20–80% operating range and the 15% minimum level setpoint below which the liquid HCl centrifugal transfer pump risks cavitation and mechanical seal dry-out; 46th upward-direction attack — FIRST anhydrous HCl gas production attack; FIRST Mannheim process attack; FIRST HCl vaporizer dry-out attack in the Glyphward portfolio)

Liquid anhydrous HCl (AHCl) from ISO tank car delivery is received into a liquid HCl storage vessel (typically 5–20 t; carbon steel with PTFE or PVDF lining; design pressure 25–35 bar; design temperature −50 to +60°C) before being vaporised in a steam-heated or hot-water-heated shell-and-tube vaporiser (steam chest on shell side; liquid HCl on tube side; steam at 1.5–3 bar gauge). The liquid HCl centrifugal transfer pump circulates liquid HCl from the storage vessel through the vaporiser tubes at a controlled flow rate to achieve the required vapour generation rate for downstream process supply (typically 50–5,000 kg/hr gas HCl at 2–10 bar). The transfer pump requires a minimum liquid level in the vaporiser vessel of approximately 15–20% to maintain flooded suction (Net Positive Suction Head required, NPSHᵣ: 2–4 m for typical centrifugal pump designs; at liquid HCl vapour pressure 40 bar at 20°C, the vessel must maintain sufficient head above the pump suction to prevent flashing). Below 15% liquid level, the pump suction head approaches the HCl vapour pressure; the liquid at the pump inlet flashes to vapour (cavitation), forming gas-lock in the pump impeller. Cavitation in a liquid HCl pump causes: (a) loss of pump flow (no liquid HCl delivery to vaporiser; downstream processes starved of HCl gas); (b) mechanical damage to impeller and seal faces from vapour-phase implosion forces; (c) mechanical seal dry-running (the liquid HCl film between seal faces evaporates; carbon/SiC seal faces run dry for >10 seconds; face temperatures above 200°C; o-ring failure at the seal face; HCl gas path created through failed seal). A failed liquid HCl pump mechanical seal releases approximately 0.5–2.0 kg/min HCl gas in a continuous release — at HCl vapour pressure 40 bar, the driving force for release through a 3 mm seal leak path is approximately 1,400 Pa/m (Fanning friction; approximated pipe flow), giving a gas release rate of 0.8 kg/min HCl at ambient conditions. Liquid HCl vaporiser systems at industrial facilities are subject to OSHA PSM (TQ 5,000 lbs; ISO tank at 20,000 kg = 44,000 lbs, 8.8× TQ) and EPA RMP worst-case release analysis for HCl (ALOHA or RMP∗Comp; 50 ppm IDLH endpoint; WCS: full ISO tank release; ARS: pump seal failure 0.8 kg/min).

An adversarial perturbation targeting the liquid HCl vaporiser liquid level display AI applies a ±8 DN upward shift to the pixel region encoding the level percentage in the rendered DCS display — shifting the apparent liquid level from 18% (approaching the 15% minimum setpoint; from an ISO tank transfer valve CV-301 position error — the valve positioner 4–20 mA signal drifted 2 mA high, driving the valve 20% more closed than commanded, reducing liquid HCl transfer rate from 280 kg/hr to 85 kg/hr while vaporiser demand remained at 220 kg/hr — net drawdown 135 kg/hr draining the vaporiser vessel) to 52% (comfortably within the 20–80% operating range; classified as normal). This is the 46th upward-direction attack in the Glyphward industrial AI portfolio — the FIRST anhydrous hydrogen chloride gas production attack; FIRST Mannheim process attack; FIRST HCl vaporiser dry-out attack. On a 0–100% level display at 200 px height (0.5%/px), the actual 18% bar occupies 36 px; the ±8 DN upward-perturbed image classifies to approximately 104 px, corresponding to 52%. The SCADA reports “liquid HCl vaporiser level nominal.” The vaporiser vessel drains from 18% to below 15% in approximately 22 minutes at 135 kg/hr net drawdown; the liquid HCl transfer pump loses flooded suction; cavitation begins (audible hammering at 120–150 dB; pump bearing temperature rising at 4°C/minute); after 8 minutes of dry-run cavitation, the double mechanical seal inner face fails; HCl gas exits through the failed seal at 0.8 kg/min into the vaporiser room. Free tier — 10 scans/day, no card required.

4. HCl distribution pipeline pressure display AI (Emerson Rosemount 3051CD HCl pipeline pressure AI / Yokogawa DPharp EJX110A HCl gas distribution pressure AI / Endress+Hauser Cerabar S HCl pipeline AI / Siemens SITRANS P DS III HCl gas pressure AI / ABB 2600T Series HCl distribution pressure transmitter AI — rendered DCS pressure trend AI classifying the HCl gas distribution pipeline pressure against the 2–8 bar operating range and the 10 bar design pressure limit above which HCl pipeline expansion joints, PTFE-lined flanges, and carbon steel relief valves approach their proof-test pressure ratings)

Anhydrous HCl gas is distributed from the vaporiser to process users through carbon steel (CS) pipelines with PTFE-lined components at all mechanical joints (flanges, tees, sampling points) because HCl dry gas corrodes carbon steel at acceptable rates below 10 ppm moisture content, but wet HCl (above 10 ppm water) corrodes CS at 12–50 mm/year. The distribution pipeline operates at 2–8 bar gauge; pressure exceedances above 10 bar gauge occur when: (a) a downstream process isolation valve closes rapidly while the vaporiser continues to supply HCl gas (blocked-in pressure build-up); (b) the HCl vaporiser steam supply increases unexpectedly (steam supply bypass valve leaks through, over-pressurising the vapour space); (c) a downstream HCl consumer trips (auto-closes its HCl feed valve) without simultaneously tripping the HCl supply. Pipeline pressure relief valves (set at 12–14 bar for 10 bar design pipelines) discharge to an HCl absorber or caustic neutralisation vessel; if the relief valve fails to open on pressure exceedance (springs corroded by traces of wet HCl at the relief valve body; PTFE seat deformation from cycling), the pipeline reaches the proof test pressure of the weakest component — typically PTFE-lined flanges (Teflon face gaskets; proof pressure typically 1.25× design = 12.5 bar for 10 bar design; above proof, the PTFE flange face extrudes, releasing HCl gas at the flange face). AI systems classify the pipeline pressure trend as: 2–8 bar (nominal), 8–10 bar (elevated; investigate upstream/downstream), above 10 bar (trip HCl supply; open HCl pipeline to absorber blowdown).

An adversarial perturbation targeting the HCl distribution pipeline pressure display AI applies a ±8 DN downward shift to the pixel region encoding the pipeline pressure in the rendered DCS trend — shifting the apparent pipeline pressure from 11.8 bar (1.8 bar above the 10 bar design; from a simultaneous trip of three HCl consumer users during a plant electrical event that closed all three HCl feed valves within 2 seconds; vaporiser continued to supply at 180 kg/hr; no vaporiser pressure auto-trip logic was implemented) to 6.2 bar (within the normal 2–8 bar operating range; classified as nominal). The SCADA reports “HCl distribution pipeline pressure nominal.” At 11.8 bar, the PTFE-lined flange faces on the 3-inch HCl pipeline at the vaporiser outlet are loaded to 118% of design pressure; PTFE face extrusion at the weakest flange (an 8-year-old gasket with 22% creep compression from previous bolt tightening) releases HCl gas at the flange joint, beginning as a 200 mg/min seep that escalates to 3 kg/min as the PTFE gasket rotates out of the flange face.

Integration: anhydrous HCl gas production AI with Glyphward pre-scan gate

Glyphward integrates as a pre-scan gate at every rendered-image ingestion boundary in the anhydrous HCl gas production and distribution monitoring pipeline — before Mannheim furnace temperature AI processes rendered DCS temperature trend images, before HCl absorber tail-gas exit AI processes rendered analyzer concentration display images, before liquid HCl vaporiser level AI processes rendered DCS level display images (46th upward attack), and before HCl pipeline pressure AI processes rendered DCS pressure trend images. Threshold 35 for anhydrous HCl AI reflects: OSHA PSM HCl TQ 5,000 lbs (single ISO tank = 8.8× TQ); ACGIH TLV-C 2 ppm (most protective ceiling in routine industrial gas portfolio); NIOSH IDLH 50 ppm; and HCl’s distinctive toxicological property of immediate-onset irritation at TLV-C — any lapse in monitoring carries no delayed-warning margin.

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_***"

# Anhydrous HCl gas AI contexts: threshold 35
# OSHA PSM HCl TQ: 5,000 lbs (single ISO tank = 44,000 lbs = 8.8× TQ).
# NIOSH IDLH: 50 ppm; ACGIH TLV-C: 2 ppm (ceiling; immediate irritant).
# 46th upward-direction attack (vaporizer level: dry-out shown as adequate).
# FIRST anhydrous HCl gas; FIRST Mannheim process; FIRST HCl vaporizer attack.
HCL_THRESHOLD = 35

class HClContext(StrEnum):
    MANNHEIM_FURNACE_TEMP   = auto()  # Mannheim muffle temperature °C
    ABSORBER_EXIT_HCL_PPM   = auto()  # HCl ppm at absorber tail-gas exit
    VAPORIZER_LIQUID_LEVEL  = auto()  # Liquid HCl vaporizer level % (46th ↑)
    PIPELINE_PRESSURE_BAR   = auto()  # HCl distribution pipeline pressure bar

async def scan_hcl_frame(
    frame_b64: str,
    context: HClContext,
    facility_id: str,
    instrument_tag: str,
) -> dict[str, Any]:
    payload = {
        "image_b64": frame_b64,
        "context": context,
        "facility_id": facility_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_hcl(
    frame_b64: str,
    context: HClContext,
    facility_id: str,
    instrument_tag: str,
) -> None:
    result = await scan_hcl_frame(frame_b64, context, facility_id, instrument_tag)
    if result["adversarial_score"] >= HCL_THRESHOLD:
        raise AdversarialHClImageError(
            f"Adversarial injection detected in {context} (score {result['adversarial_score']}) "
            f"at facility {facility_id} instrument {instrument_tag}. "
            "Frame withheld from AI monitoring pipeline."
        )

class AdversarialHClImageError(RuntimeError):
    pass