BM-057 | CONCEPTUAL DESIGN OF 50,000 TPA SPECIALTY GRADE ATH PLANT

Comprehensive Feasibility Study, Four-Grade Product Mix, Process Flowsheet, Capex, Opex & Financial Appraisal

Author: Rajendra Kunwar, Bayer Process Expert

Project Identification:	BM-057 (Specialty Chemical Facility)
Nominal Plant Capacity:	50,000 Metric Tonnes Per Annum (tpa)
Target Product Slate:	1. Dry Chemical | 2. Fire Retardant | 3. Toothpaste | 4. High Purity
Document Status & Date:	Final Feasibility & Conceptual Design Report | November 2026

Executive Summary 

This document presents the detailed technical and commercial conceptual design for project BM-057, a modern 50,000 metric tonne per annum (tpa) specialty Aluminium Trihydrate (ATH / Alumina Trihydrate / Al(OH)3) manufacturing facility. Designed to process wet alumina hydrate cake from refinery precipitation into four high-value specialty grades, the plant delivers robust product flexibility, superior energy efficiency, and strict zero liquid discharge (ZLD) environmental compliance. 

The plant design addresses four primary market segments: (1) Dry Chemical Grade for aluminium chemical synthesis, (2) Fire Retardant Filler Grade for polymer compounding and flame-proof cable jackets, (3) Toothpaste Grade for dentifrice polishing abrasives, and (4) High Purity Grade for catalyst carriers and electronic glass formulations.

Project Highlights: Key Financial & Operating Benchmarks:

·      Total Plant Capacity: 50,000 tpa total capacity across 330 operational days/year (151.5 tpd nominal rate). 

·   Total Capital Investment (CAPEX): $25.00 Million USD (approx. ₹207.5 Crore INR) including complete equipment, civil works, utilities, and EPCM. 

·    Operating Expenditure (OPEX): $404.40 per tonne of blended output ($18.20 Million USD at 90% operating capacity).

·      Projected Annual Revenue: $29.50 Million USD at 90% capacity, yielding an EBITDA of $11.30 Million USD (38.3% EBITDA margin). 

·      Financial Viability: Internal Rate of Return (IRR) of 26.4%, Net Present Value (NPV @ 10%) of $24.80 Million USD, and a Simple Payback Period of 3.6 Years.

1. Broad Market Scenario & Demand Drivers 

The global Aluminium Trihydrate (ATH) market is valued at approximately $1.85 Billion USD in 2026 and is projected to expand at a Compound Annual Growth Rate (CAGR) of 5.8% through 2032. ATH (CAS No. 21645-51-2) represents the world's most widely utilized eco-friendly, halogen-free flame retardant and functional inorganic filler.

1.1  Key Market Drivers by Segment

·       Flame Retardant & Polymer Compounds: Stringent building codes, automotive electrification (EV battery pack enclosures), and electrical insulation requirements (UL 94 V-0 standards) drive demand for ultrafine (D50 < 3.5 µm) and surface-modified ATH fillers. When heated above 220°C, ATH undergoes endothermic decomposition, releasing 34.6% of its weight as water vapor, which dilutes combustible gases and cools the substrate without liberating toxic smoke. 

·      Toothpaste & Oral Care: Modern dentifrice formulations favor precipitated ATH due to its controlled Relative Dentin Abrasiveness (RDA 40–60), high refractive index compatibility with sorbitol (1.57), and excellent fluorine compatibility compared to silica or calcium carbonate. 

·   Chemical Intermediates & Water Treatment: Essential raw material for manufacturing high-purity aluminium chemicals including Aluminium Sulphate (alum), Polyaluminium Chloride (PAC) for municipal water purification, Synthetic Zeolites, and Aluminium Fluoride (AlF3) for aluminium smelting. 

·    High Purity Specialty Applications: High-purity grades (Al(OH)3 > 99.9%, Na2O < 0.05%) are increasingly specified for petroleum refining catalyst substrates, specialty glass, and ceramic micro-substrates.

Figure: BM-057 Product-Mix Allocation and Annual Tonnage Breakdown

2. Detailed Technical Specifications of Target ATH Grades

Project BM-057 is configured to produce four distinct commercial grades of ATH. Each grade requires rigorous control over particle size distribution (PSD), whiteness index, total/soluble soda (Na2O), iron content, and oil absorption.

2.1 Master Technical Specifications Matrix

 

Parameter / Test Method	Grade 1: Dry Chem.	Grade 2: Flame Ret.	Grade 3: Toothpaste	Grade 4: High Purity
Al(OH)3 Content (%)	≥ 99.2%	≥ 99.6%	≥ 99.6%	≥ 99.9%
Al2O3 Content (%)	≥ 64.5%	≥ 65.0%	≥ 65.0%	≥ 65.2%
Fe2O3 Content (%)	≤ 0.020%	≤ 0.012%	≤ 0.008%	≤ 0.003%
Total Na2O Content (%)	≤ 0.35%	≤ 0.20%	≤ 0.10%	≤ 0.04%
SiO2 Content (%)	≤ 0.025%	≤ 0.015%	≤ 0.010%	≤ 0.005%
Moisture at 105°C (%)	≤ 0.30%	≤ 0.20%	≤ 0.25%	≤ 0.15%
Loss on Ignition (1000°C)	34.2 – 34.8%	34.4 – 34.8%	34.5 – 34.8%	34.6 – 34.8%
Particle Size D50 (µm)	45.0 – 75.0 µm	1.5 – 4.5 µm	8.0 – 12.0 µm	1.0 – 3.0 µm
Whiteness Index (Hunter L)	≥ 92.0%	≥ 96.5%	≥ 97.5%	≥ 98.5%
Special Attribute / Functional	Coarse Free Flow	Silane Coated	Low RDA (40-60)	Low Trace Metal

2.2 Grade-by-Grade Technical Descriptions

Grade 1: Dry Chemical Grade ATH — A coarse, free-flowing white crystalline powder produced by direct flash drying of washed precipitation cake. Designed for rapid dissolution in sulphuric acid or caustic liquor to produce alum, PAC, and aluminium fluoride.

Grade 2: Fire Retardant Filler Grade ATH — An ultrafine, micronized, high-whiteness powder subjected to fluid energy milling and optional surface modification with vinyl-silane or stearic acid (0.8–1.2 wt%). Provides excellent fire suppression, smoke mitigation, and low viscosity build-up in PVC cables, epoxy resins, and SMC/DMC automotive parts.

Grade 3: Toothpaste Grade ATH — A specialized precipitated grade engineered with a controlled, narrow particle size distribution (D50 ~ 8–12 µm) and smooth particle morphology. Provides soft dentin cleaning without tooth enamel abrasion (RDA 40–60), high fluoride retention due to ultra-low soluble soda (Na2O < 0.05%), and clean taste profile.

Grade 4: High Purity Grade ATH — An ultra-pure grade manufactured via multi-stage deionized water washing and chemical purification. Trace transition metals (Fe, Cu, Cr) are kept below 30 ppm, making it ideal for pharmaceutical antacids, catalyst carriers, and high-transmission optical glass.

Figure: Particle Size D50 and Whiteness Comparison Across Target ATH Grades

3. Process Technology & Conceptual Flowsheet Design

The BM-057 facility adopts an integrated hydro-metallurgical Bayer process route followed by controlled liquor decomposition / neutralization precipitation with high-efficiency filtration, drying, micronization, and surface coating adopting a few key unit operations as described hereunder. 

3.1 Key Unit Operations

·  Unit 100 — Seeded Crystallization: Purified sodium aluminate liquor is fed into stirred precipitation tanks where temperature, seed concentration, and agitation rate are precisely controlled to establish target particle nucleation.

 

·   Unit 200 — Filtration & Counter-Current Washing: The slurry is transferred to horizontal vacuum belt filters equipped with multi-stage counter-current deionized water wash headers to reduce residual soda (Na2O) below 0.10%.

 

·     Unit 300 — Flash Drying: Washed filter cake (12–15% moisture) is processed through a gas-fired spin-flash dryer operating at 140–160°C inlet temperature to yield dry coarse ATH powder (<0.2% moisture).

 

·     Unit 400 — Air Jet Milling & Classification: For Fire Retardant and High Purity grades, dried powder is fed into fluid energy air-jet mills integrated with dynamic air classifiers to achieve sub-micron and micronized distributions without iron contamination.

·    Unit 500 — Surface Coating & Packaging: Micronized FR powder is fed into a continuous high-speed pin mixer where silane coupling agent or stearic acid is atomized and coated onto particle surfaces at 80°C.

Figure: BM-057 Conceptual Process Flow Diagram (50,000 tpa Plant)

4. Product-Mix & Operational Strategy

To maximize gross margin while maintaining continuous plant utilization, the 50,000 tpa capacity is allocated across the four grades based on market demand and contribution margins. 

Grade Name	Share (%)	Annual (tpa)	Daily Rate (tpd)	Primary Packaging
Dry Chemical Grade	40.0%	20,000 tpa	60.6 tpd	1000kg Jumbo FIBC
Fire Retardant Filler Grade	36.0%	18,000 tpa	54.5 tpd	25kg Paper Bags / FIBC
Toothpaste Grade	14.0%	7,000 tpa	21.2 tpd	25kg Valve Bags
High Purity Grade	10.0%	5,000 tpa	15.2 tpd	25kg Sealed Fiber Drums
TOTAL PLANT OUTPUT	100.0%	50,000 tpa	151.5 tpd	Integrated Warehouse

5. Capital Expenditure (CAPEX) Estimate

The total estimated capital cost for project BM-057 is $25.00 Million USD (approx. ₹207.5 Crore INR). The estimate has been prepared to Class 3 feasibility accuracy (±15%).

Item	Cost Center Description	Cost ($M USD)	Cost (₹ Crore)
1.0	Major Process Equipment (Precipitation, Filters, Flash Dryers)	$10.80 M	₹ 89.64 Cr
2.0	Micronization, Air Jet Milling & Surface Coating Package	$3.80 M	₹ 31.54 Cr
3.0	Civil Works, Factory Buildings & Steel Structures	$3.50 M	₹ 29.05 Cr
4.0	Utilities (Boiler, Compressed Air, RO Water, ZLD ETP)	$2.60 M	₹ 21.58 Cr
5.0	Electrical Substation, MCC & DCS/PLC Automation	$1.80 M	₹ 14.94 Cr
6.0	Engineering, EPCM, Pre-operative & Contingencies	$2.50 M	₹ 20.75 Cr
TOTAL	TOTAL ESTIMATED PROJECT CAPEX	$25.00 M	₹ 207.50 Cr

6. Operating Expenditure (OPEX) Estimate

Operating costs are modeled based on continuous processing at 90% capacity utilization (45,000 tpa output). The blended average cost of production is $404.40 per tonne of finished ATH. 

Cost Component	Specific Consumption	Unit Rate	$/Tonne Out	Annual ($M)
Raw Hydrate Cake / Feed	1.02 t / t ATH	$230 / tonne	$234.60	$10.56 M
Power & Utilities	110 kWh / t	$0.09 / kWh	$62.50	$2.81 M
Natural Gas (Drying)	38 Nm³ / t	$0.45 / Nm³	$17.10	$0.77 M
Silane / Coating Chemicals	Weighted Blend	Market Rate	$28.00	$1.26 M
Direct Labour & Overhead	75 Personnel	Loaded Rate	$26.20	$1.18 M
Maintenance & Spare Parts	3% Equipment	Annual	$16.00	$0.72 M
Packaging & Logistics	Bags & FIBCs	Standard	$20.00	$0.90 M

7. Indicative Financial Appraisal & Viability Metrics

Financial evaluation assumes a 10-year operating horizon, 70:30 Debt-to-Equity financing structure at 8.5% interest rate, and a 10% Weighted Average Cost of Capital (WACC) discount rate.

7.1 Revenue Realization & Margin Matrix

Grade Description	Volume @ 90%	Selling Price	Annual Revenue	EBITDA Margin
Dry Chemical Grade	18,000 tpa	$360 / tonne	$6.48 Million	22.5%
Fire Retardant Filler Grade	16,200 tpa	$720 / tonne	$11.66 Million	43.0%
Toothpaste Grade	6,300 tpa	$820 / tonne	$5.17 Million	48.2%
High Purity Grade	4,500 tpa	$1,380 / tonne	$6.21 Million	61.5%
BLENDED TOTAL	45,000 tpa	$655.50 / t avg	$29.52 Million	38.3% avg

 

7.2 Key Financial Performance Metrics

 

Financial Indicator	Project Benchmark	Feasibility Assessment
Project Internal Rate of Return (IRR)	26.4%	Highly Attractive (>15% Hurdle)
Net Present Value (NPV @ 10%)	$24.80 Million USD	Strong Value Creation
Simple Payback Period	3.6 Years	Rapid Capital Recovery
Break-Even Capacity Utilization	41.5%	High Safety Margin against Downturns
Average Debt Service Coverage (DSCR)	2.45x	Excellent Bankability & Debt Capacity

 

Figure: Financial Snapshot of Project BM-057 (At 90% Operating Capacity)

8. Conclusion & Strategic Next Steps

The conceptual design for BM-057 confirms that establishing a 50,000 tpa four-grade specialty ATH facility is highly viable technically, environmentally, and commercially. The high proportion of specialty Fire Retardant, Toothpaste and High Purity grades provides strong margin insulation against commoditized alumina chemical cycles.

Strategic Recommendations:

 

1. Pilot Validation: Commission detailed pilot-scale crystallization trials to firm up particle morphology and soda leaching parameters for Toothpaste and High Purity grades. 

2.  Feedstock Security: Establish long-term raw alumina hydrate cake supply contracts with regional bauxite refineries to hedge against feedstock price volatility. 

3. EPCM Execution: Proceed to Front-End Engineering Design (FEED) and initiate environmental permitting for the Zero Liquid Discharge (ZLD) effluent treatment plant.

 

CETI ENTERPRISES, INDIA

CETI Enterprises supports alumina industry professionals through technical training, process audits, calcination performance assessment, energy optimization, process troubleshooting, equipment design review, debottlenecking and refinery improvement programs. For further details please visit our website at https://ceti.co.in

About the Author: Rajendra Kunwar is Bayer Process & Alumina Technology Specialist. Through CETI Enterprises, he offers expert technical consultancy in customized online / onsite team training, process for production of specialty grade ATH & Alumina, efficiency enhancement, quality improvement, energy reduction, cost reduction, troubleshooting and plant debottlenecking. To explore how we can support your plant operations or upcoming expansion, please contact us at rajendra@ceti.co.in