Prompt injection in calcium hypochlorite HTH pool chlorine manufacturing dryer AI

Three adversarial injection surfaces in calcium hypochlorite HTH pool chlorine manufacturing AI

1. Dryer outlet product temperature display AI (Yokogawa EJA110A Ca(OCl)₂ product outlet thermocouple SCADA display AI / Emerson Rosemount 3051 dryer product exit temperature display AI / ABB TTF300 Ca(OCl)₂ rotary dryer product temperature SCADA display AI / Honeywell STT170 dryer discharge temperature display AI / Endress+Hauser iTEMP TMT72 Ca(OCl)₂ product exit belt/conveyor temperature display AI — rendered SCADA Ca(OCl)₂ dryer outlet product temperature display AI classifying the product exit temperature at 40–55°C against design range, with high alarm at 65°C and high-high trip at 75°C triggering dryer shutdown and CO₂ inert purge activation — 84th upward attack; FIRST HTH manufacturing attack; FIRST Ca(OCl)₂ attack; FIRST pool chlorine manufacturing AI attack; FIRST high-test hypochlorite dryer attack)

The Ca(OCl)₂ rotary dryer operates with inlet air at 50–80°C and product exit at 40–55°C design temperature; the 10–15°C temperature increase from product to inlet air reflects the heat absorbed by moisture evaporation (latent heat water evaporation 2,257 kJ/kg; at design 1.0 wt% moisture removal from 5,000 kg/hr wet product = 50 kg/hr H₂O evaporation; heat required 50 × 2,257 = 113 MJ/hr = 31 kW — modest heat load; dryer capacity is not heat-limited but moisture-removal-rate limited). The product temperature at dryer exit must remain below 65°C (high alarm) for two reasons: (a) Ca(OCl)₂ decomposition rate is negligible below 80°C in dry form (DSC: decomposition onset ≈ 100°C; exothermic peak ≈ 140–160°C in fresh, pure Ca(OCl)₂); but decomposition onset is reduced to 80–90°C in the presence of moisture, trace metals (Fe²⁺; Cu²⁺; Ni²⁺; these catalyse OCl⁻ decomposition: OCl⁻ → Cl⁻ + 1/2 O₂; k 10× faster in presence of 1 ppm Fe²⁺), and organic material (wood dust, oil, gasket material — all react exothermically with Ca(OCl)₂ above 50–60°C); (b) the dryer drum handling 65–70 wt% Ca(OCl)₂ solid at elevated temperature is a potential dust-cloud ignition source: Ca(OCl)₂ dust is dispersed in the drying air flow; at product temperature above 65°C, any organic contamination (dryer drum lubricant seal; wooden residue from product handling) in contact with the hot Ca(OCl)₂ can auto-ignite (organic material autoignition in contact with Ca(OCl)₂): 50–100°C onset for dry hay; 60–80°C for oil-soaked rags; 80–100°C for most organic solids). The standard engineered safeguard is a product-exit thermocouple with high-alarm at 65°C (reduce dryer air temperature) and high-high trip at 75°C (immediate dryer shutdown; CO₂ inert gas purge injection into dryer drum to suppress any incipient Ca(OCl)₂ decomposition; isolate product to batch cooler). The AI monitors the rendered SCADA thermocouple display for the dryer exit temperature.

The adversarial upward pixel attack shifts the dryer exit product temperature display from 68°C (actual; above the 65°C high alarm; dryer air temperature is running slightly too hot due to inlet air temperature controller drift; product is approaching the 75°C high-high trip zone; DCS alarm is active but AI is the primary response layer in the AI-assisted operator system) to 92°C (displayed; above the 75°C high-high trip setpoint; AI classification “dryer product temperature critically overtemperature at 92°C; approaching Ca(OCl)₂ decomposition onset; reduce dryer heat input immediately and consider emergency CO₂ purge activation.”). The DCS automatic response: dryer steam/hot-air inlet control valve closes from 72% to 8% open; CO₂ purge injection valve opens 40% (partial inert purge to suppress decomposition). The actual product temperature at 68°C → with reduced heat input, drops to 55–60°C within 15–20 minutes. The adversarial primary consequence: the CO₂ purge reduces the drying air oxygen content from 21% to approximately 13% O₂; at <10% O₂ in the dryer air, Ca(OCl)₂ dust suspension can decompose releasing O₂ without air-supplied ignition — Ca(OCl)₂ is a self-oxidising material (the oxidant is contained within the molecule: Ca(OCl)₂ → CaCl₂ + O₂; the O₂ does not need to come from the dryer air). The CO₂ purge inertisation intended to suppress combustion actually eliminates the normal dilution effect of 21% O₂ drying air on the Ca(OCl)₂ dust concentration — in 21% O₂ air, any ignition of Ca(OCl)₂ dust is partially oxygen-limited; in CO₂-purged air at 8% O₂, the Ca(OCl)₂ dust cloud has no additional oxygen limitation (all O₂ comes from decomposition itself). This is the 84th upward attack — FIRST HTH manufacturing attack; FIRST Ca(OCl)₂ attack; FIRST pool chlorine manufacturing AI attack; FIRST high-test hypochlorite dryer attack. Free tier — 10 scans/day, no card required.

2. Chlorinator temperature display AI (Yokogawa EJA110A chlorinator jacket cooling water outlet temperature display AI / Emerson Rosemount 3051 chlorinator bulk slurry temperature display AI / ABB TTF300 Ca(OCl)₂ chlorinator temperature SCADA display AI / Endress+Hauser iTEMP TMT72 chlorinator slurry temperature display AI / Honeywell STT170 chlorinator bulk temperature display AI — rendered SCADA Ca(OCl)₂ chlorinator temperature display AI classifying the chlorination slurry temperature at 0–15°C against design range, with high alarm at 20°C and automatic Cl₂ feed reduction at 18°C to prevent Ca(OCl)₂ decomposition in the chlorinator)

The Ca(OCl)₂ chlorination step (Ca(OH)₂ slurry + Cl₂ gas; 0–15°C; 2–6 bar Cl₂ partial pressure) must be maintained at low temperature to: (a) maximize Ca(OCl)₂ yield (at >20°C, Ca(OCl)₂ solubility in the chlorination slurry increases, reducing crystallisation yield; at >35°C, Ca(OCl)₂ begins to decompose in the alkaline slurry via Ca(OCl)₂ + H₂O → Ca(OH)(OCl) + HOCl → CaCl₂ + H₂O + O₂); (b) maintain Cl₂ absorption efficiency in the slurry (Henry’s law Cl₂ solubility in aqueous Ca(OH)₂ slurry decreases with temperature: at 5°C, Cl₂ absorption 99%+; at 20°C, 92–95%; at 35°C, 80–85%; unabsorbed Cl₂ exits in the chlorinator vent as Cl₂ slip); (c) prevent Ca(OCl)₂ crystal agglomeration (fine crystals at low temperature; coarse agglomerates at >20°C that are harder to filter and dry to specification). Chlorinator temperature is controlled by jacket cooling water (typically 0–5°C chilled water from a dedicated refrigeration system; chillers sized for the Cl₂ absorption exotherm = approximately 65 kJ/mol Cl₂ absorbed = at Cl₂ feed rate 2,000 kg/hr = 2,000/71 × 65 = 1,831 MJ/hr = 509 kW chilling duty; standard HTH chlorinator chiller capacity: 600–800 kW). The AI monitors the rendered SCADA chlorinator temperature display and controls the Cl₂ feed rate (at 18°C alarm, reduce Cl₂ feed to reduce absorption exotherm and allow temperature to recover; at 20°C, automatic Cl₂ feed valve closure).

The adversarial upward pixel attack shifts the chlorinator temperature display from 8°C (actual; within design range 0–15°C; cooling is adequate; Cl₂ absorption running at full rate; product forming normally) to 28°C (displayed; above the 20°C Cl₂-shutoff alarm setpoint; above the 18°C Cl₂-reduction setpoint; AI classification “chlorinator critically overtemperature at 28°C; above Cl₂ shutoff threshold 20°C; immediately close Cl₂ feed control valve to prevent Ca(OCl)₂ decomposition in chlorinator; investigate cooling system failure.”). The DCS response: Cl₂ feed control valve closes from 85% to 0% (full shutoff). Actual chlorinator temperature remains at 8°C with Cl₂ feed shut off: (a) Cl₂ feed is stopped but Cl₂ in the pipeline from the liquid Cl₂ vaporiser to the chlorinator continues to pressure-equalise; Cl₂ pressure in the chlorinator feed line rises as feed valve is closed; Cl₂ pressure at the chlorinator inlet = 3.5 bar (liquid Cl₂ vaporiser supply pressure). The Cl₂ feed pipe depressurises through the closed valve vent (minor Cl₂ release). More significantly: (b) the Ca(OH)₂ slurry feed (milk of lime) continues at design flow into the chlorinator (Ca(OH)₂ feed valve was not affected by the adversarial action; only Cl₂ feed was shut); the chlorinator now contains Ca(OH)₂ slurry with no Cl₂ addition; pH rises from 11–12 (design) to 12.5–13.0 (excess Ca(OH)₂); the Ca(OH)₂ slurry overflows toward the product filtration system without Ca(OCl)₂ content; (c) when the adversarial display is eventually corrected (either by the operator noticing the process anomaly or by the AI self-correcting after pixel injection ceases), the Cl₂ feed resumes at full flow into a chlorinator now containing excess Ca(OH)₂ slurry at pH 12.5–13.0; the exothermic Cl₂ absorption into the concentrated Ca(OH)₂ slurry occurs at 8.5× the design Cl₂ absorption rate (excess Ca(OH)₂ in slurry = higher alkalinity = faster Cl₂ absorption rate by Le Chatelier); the chlorinator temperature spikes from 8°C to 22–28°C in 4–8 minutes from the full-flow Cl₂ resumption into over-charged slurry — a real overtemperature event caused by the adversarial AI action of shutting off Cl₂ and allowing Ca(OH)₂ to accumulate. Free tier — 10 scans/day, no card required.

3. Ca(OCl)₂ product moisture display AI (Mettler-Toledo Moisture Analyzer Karl Fischer SCADA display AI / Near-infrared NIR moisture sensor Ca(OCl)₂ inline SCADA display AI / Sartorius MA35 moisture display AI / Endress+Hauser Liquidline CM44 conductivity moisture proxy display AI / Yokogawa Raman inline Ca(OCl)₂ moisture SCADA display AI — rendered SCADA Ca(OCl)₂ product moisture wt% display AI classifying the product moisture against the design specification of 0.5–1.5 wt% with high alarm at 2.5 wt% and low alarm at 0.4 wt% to prevent under-dry and overdried Ca(OCl)₂ stability problems)

Ca(OCl)₂ product moisture specification (0.5–1.5 wt% moisture) is a critical quality and safety parameter: above 1.5 wt%, the product hydrolyses in the packaging (Ca(OCl)₂ + H₂O → Ca(OH)(OCl) + HOCl), reducing available chlorine content and generating HOCl vapour (acrid chlorine-like odour; OSHA PEL 1 ppm Cl₂-equivalent; HOCl is more reactive than Cl₂ in some oxidation reactions) inside the sealed product drum or bag — pressurisation risk; product degradation; customer quality complaint. Below 0.5 wt% moisture, Ca(OCl)₂ is overly sensitised to heat- and contamination-initiated decomposition: moisture acts as a thermal stabiliser (water has high heat capacity; absorbs decomposition initiation heat; at 0.5 wt% moisture content, approximately 40 g H₂O per kg Ca(OCl)₂ absorbs 167 kJ/kg before reaching 100°C decomposition onset, providing meaningful thermal buffering). Inline NIR moisture measurement (near-infrared reflectance spectroscopy at 1,450 nm and 1,940 nm OH absorption bands) is the standard continuous moisture monitoring method on the Ca(OCl)₂ product conveyor/exit belt at HTH manufacturing plants; the NIR sensor reads the rendered SCADA moisture display which the AI interprets for dryer temperature setpoint adjustment. If NIR reads 1.1 wt% (nominal; in specification; dryer operating normally), no setpoint adjustment. If NIR shows 4.8 wt% (displayed; above 2.5 wt% high alarm; AI classification “Ca(OCl)₂ product moisture critically above specification; risk of hydrolysis in packaging; increase dryer air temperature from 65°C to 80°C to increase moisture removal rate and bring product moisture within specification”), while actual moisture is 0.9 wt% (normal; NIR adversarially perturbed): the AI/DCS increases dryer inlet air temperature from 65°C to 80°C. Product temperature at dryer exit (currently 48°C at 65°C inlet air) rises to 58–62°C at 80°C inlet air (within the high alarm zone 65°C but not yet triggering it). Product moisture drops from 0.9 wt% to 0.35–0.40 wt% (below the 0.4 wt% low alarm but the low alarm is displayed as 1.1 wt% by the adversarial NIR so the alarm does not fire).

The overdried Ca(OCl)₂ at 0.35–0.40 wt% moisture entering the product storage warehouse is now at the bottom boundary of thermal stability. In a warehouse storage pile (2.0 m high; 10 tonne bulk bag; core temperature can reach 5–10°C above ambient due to poor heat dissipation at pile center; insulated bulk bag; polyethylene liner): on a summer day (ambient 32°C; pile core 37–42°C); overdried Ca(OCl)₂ at 0.35% moisture at 40°C: decomposition rate is non-trivial (k at 40°C approximately 10⁻⁷·⁶ s⁻¹ for dry Ca(OCl)₂; self-heating rate approximately 0.04°C/hr for 10 tonne pile); any contamination event (mouse droppings on Ca(OCl)₂ surface; oil spill from forklift; wooden pallet resin degradation; 0.1 g organic contamination contact with Ca(OCl)₂ at 40°C): Ca(OCl)₂ + organic matter (e.g., cellulose (C₆H₁₀O₅)ⁿ) → exothermic reaction; CaCl₂ + CO₂ + H₂O + heat; initiation temperature for Ca(OCl)₂ / organic contamination: approximately 50–70°C for dry Ca(OCl)₂ (lower than the 80–100°C for moist Ca(OCl)₂). The overdried product is therefore significantly more vulnerable to contamination-initiated runaway than properly moistened product — and the adversarial moisture display attack that drove over-drying occurred at the manufacturing facility, not the warehouse; by the time the product reaches the customer’s pool supply warehouse, no moisture re-measurement is done. The consequence chain (adversarial NIR display → dryer overheating → overdried product → warehouse fire from contamination initiation) spans the manufacturing facility and the downstream supply chain, with the initiating adversarial event potentially invisible in any post-incident investigation that focuses on the warehouse fire rather than the manufacturing dryer AI. Free tier — 10 scans/day, no card required.

Integration: calcium hypochlorite HTH manufacturing AI with Glyphward pre-scan gate

Glyphward integrates as a pre-scan gate at every rendered-image ingestion boundary in the Ca(OCl)₂ HTH manufacturing AI pipeline — before the dryer outlet product temperature AI processes rendered thermocouple SCADA display images, before the chlorinator temperature AI processes rendered SCADA jacket cooling display images, and before the Ca(OCl)₂ product moisture AI processes rendered NIR/Karl Fischer display images. Threshold 28 for HTH manufacturing AI reflects: Cl₂ PSM TQ 1,500 lbs; Ca(OCl)₂ NFPA 430 Class 3 oxidizer; decomposition onset 100°C in dry form; overdried Ca(OCl)₂ initiation temperature as low as 50–70°C with organic contamination; Thailand 2003 warehouse fire (200 deaths); Olin Corporation McIntosh AL; Lonza Water Treatment Conley GA; OxyChem Taft LA.

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_***"

# Ca(OCl)2 HTH manufacturing AI contexts: threshold 28
# OSHA PSM Cl2 TQ 1,500 lbs; Ca(OCl)2 NFPA 430 Class 3 oxidizer.
# Dryer decomp onset 100C; overdried <0.5 wt% moisture lowers contamination ignition.
# 84th upward attack: 92C shown when 68C actual -> dryer CO2 purge triggered
# -> self-oxidising Ca(OCl)2 dust loses O2 dilution from air -> decomp risk.
CACL2_HTH_THRESHOLD = 28

class HTHContext(StrEnum):
    DRYER_PRODUCT_TEMPERATURE = auto()  # Ca(OCl)2 exit belt temp 40-55C (84th upward)
    CHLORINATOR_TEMPERATURE   = auto()  # Chlorination slurry 0-15C design
    PRODUCT_MOISTURE_PCT      = auto()  # Ca(OCl)2 moisture wt% 0.5-1.5 design

async def scan_hth_frame(
    frame_b64: str,
    context: HTHContext,
    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_hth(
    frame_b64: str,
    context: HTHContext,
    plant_id: str,
    instrument_tag: str,
) -> None:
    result = await scan_hth_frame(frame_b64, context, plant_id, instrument_tag)
    if result["adversarial_score"] >= CACL2_HTH_THRESHOLD:
        raise AdversarialHTHImageError(
            f"Adversarial injection detected in {context} (score {result['adversarial_score']}) "
            f"at plant {plant_id} instrument {instrument_tag}. "
            "Frame withheld from Ca(OCl)2 HTH manufacturing AI pipeline."
        )

class AdversarialHTHImageError(RuntimeError):
    pass