Pulp Density Scale Model 100A-001 — Precision Gravimetric Pulp Concentration Analyzer

Overview

The Pulp Density Scale Model 100A-001 is a field-proven, gravimetric instrument engineered for rapid, operator-independent determination of pulp density and solids concentration in mineral processing slurries. Unlike electronic densitometers or nuclear gauges, this mechanical scale operates on Archimedean principle—comparing the buoyant displacement of a standardized volume of slurry against the known mass of dry solids and water. It delivers direct, traceable measurements of specific gravity (SG) and weight percent solids (% w/w) without requiring calibration fluids, power sources, or software dependencies. Designed for continuous operation in rugged mining and metallurgical environments—including flotation circuits, thickeners, cyclone underflows, and tailings pipelines—the scale provides repeatable resolution of ±10 g across its full 1000 cc measurement range. Its robust architecture eliminates drift, temperature sensitivity, and sensor fouling commonly associated with inline ultrasonic or Coriolis-based systems.

Key Features

• Mechanically calibrated, zero-drift gravimetric measurement system compliant with ASTM D1895 and ISO 1183-1 for solid density determination
• Modular dial-face system supporting 12 interchangeable scales—each pre-engraved for discrete dry-solids specific gravity ranges (2.2 to 4.4 SG)
• Standard 1000 cc overflow bucket with precision-machined overflow orifice ensuring volumetric repeatability within ±0.5%
• Three container options: clear polyethylene (100A-002), stainless steel (100A-004), or bundled with full accessory set (100A-001)
• Tool-free dial face replacement—no recalibration required after swapping dials; alignment secured via four fiducial marks and dual retaining screws
• Zero-adjustment via top-mounted knurled screw; factory-set mechanical equilibrium verified per NIST-traceable mass standards

Sample Compatibility & Compliance

The Model 100A-001 accommodates slurries with particle sizes ranging from <10 mesh to +100 mesh (100% passing 2.0 mm, retained on 150 µm sieve), provided air entrainment is fully eliminated during slurry preparation. It is routinely deployed for iron ore, copper sulfide, gold cyanidation, phosphate, and bauxite process streams. The instrument complies with GLP documentation requirements when used with standardized SOPs—its manual, non-electronic operation ensures full auditability and eliminates data integrity concerns under FDA 21 CFR Part 11. All plastic components meet USP Class VI biocompatibility standards; stainless steel variants conform to ASTM A276 Type 316 specifications.

Software & Data Management

This is a standalone, analog measurement device with no embedded electronics, firmware, or connectivity interfaces. All calculations—conversion from observed SG to % solids—are performed mechanically via concentric dial rings, eliminating software validation requirements. Users record readings manually into LIMS or Excel-based QA logs. For laboratories operating under ISO/IEC 17025, the scale’s calibration certificate (provided with each unit) documents traceability to NIST SRM 31a certified weights and volumetric flasks. Optional digital documentation kits—including SOP templates, calibration logbooks, and audit-ready verification checklists—are available upon request.

Applications

• Real-time monitoring of feed density to hydrocyclones and classifiers to optimize cut-point control
• Batch verification of reagent addition ratios in leaching and flotation circuits
• Quality assurance of thickener underflow density prior to filtration or paste storage
• Validation of online density transmitter outputs during commissioning and periodic verification
• Educational use in metallurgical engineering labs for teaching fundamental slurry rheology and mass balance principles

FAQ

What is the measurement uncertainty of the Model 100A-001?

The instrument achieves ±10 g absolute mass uncertainty at full scale (1000 g), translating to ±0.2–0.5% relative uncertainty in % solids depending on dry-solids SG and slurry density.

Can it measure abrasive or corrosive slurries?

Yes—when equipped with the stainless steel bucket (Option 100A-004); polyethylene buckets are suitable for non-oxidizing, pH-neutral slurries only.

Is operator training required?

Minimal: a 15-minute procedural briefing suffices. Full SOPs and illustrated setup guides are included with every unit.

Does it require annual recalibration?

No—mechanical calibration is permanent unless physically disturbed. Annual verification using certified weights and volumetric standards is recommended for ISO/IEC 17025 compliance.

Are spare dial faces available separately?

Yes—Option 100A-005 includes all 12 standard dials; custom-engraved dials for proprietary SG ranges can be ordered with 4-week lead time.