What Liquid Solids Control does

Liquid Solids Control Inc. is a privately-held U.S. manufacturer of inline process refractometers founded in 1977 and headquartered in Upton, Massachusetts. The company designs and builds optical concentration and density measurement instruments used to continuously monitor dissolved solids, Brix, and refractive index in industrial process streams. Its core technology relies on the Critical Angle optical measurement technique combined with an I.R. Detection System claimed to provide infinite resolution and drift elimination, with industrial sapphire prisms as the sensing interface. The company also produces a third-generation Model 1022 dual-refractometer Black Liquor Divert System, a safety-instrumented product used in pulp and paper recovery boilers to prevent smelt water explosions, fully compliant with BLRBAC recommendations.

The product portfolio centers on the Model 326 universal in-line process refractometer, complemented by a family of sensing heads, insertion probes, and green liquor probes offered in multiple materials (Duplex 2205, 316L stainless steel, Hastelloy-C, Kynar, Monel, Tantalum) to address corrosive, sanitary, and hazardous process environments. Accessories include the Gate Adaptor Isolation Valve for hot-swap maintenance, an Automatic Prism Wash System with smart-wash logic, Stahl-certified intrinsic safety barriers, and replaceable baffle assemblies. Served end markets span pulp and paper (the historical anchor), semiconductor, chemical and petrochemical, food, dairy, beverage, and sugar processing.

LSC operates an enterprise field-sales model with custom application-based quotation; each refractometer is priced individually based on process specifications, materials, and accessories, with no public price list. The company distributes directly to industrial customers from its Upton headquarters and through regional offices in Canada (Vancouver Island) and São Paulo, Brazil, supported by 24/7/365 technical service, in-house repair, and on-site preventative maintenance. The firm is closely held (no external investment disclosed), maintains 11–50 employees, and positions itself as a specialized niche supplier competing against larger diversified process-instrumentation vendors by emphasizing customization, safety compliance, and decades of application engineering.

Name

Liquid Solids Control

Legal name

Liquid Solids Control Inc.

Website

https://liquidsolidscontrol.com

Company type

Private

Founded year

1977

Operating status

Operating

Headcount range

11–50 employees

Short description

Liquid Solids Control Inc. is a U.S. manufacturer of inline process refractometers and Black Liquor Divert Systems, founded in 1977, that provides continuous concentration and density measurement for the pulp and paper, chemical, semiconductor, food, dairy, beverage, and sugar industries via custom enterprise field sales.

Ownership category

akta.pro rank

Product category

Industrial Process Refractometers

NAICS

Instruments and Related Products Manufacturing for Measuring, Displaying, and Controlling Industrial Process Variables (334513), Other Measuring and Controlling Device Manufacturing (334519)

SIC

Industrial Instruments For Measurement, Display, And Control (3823)

akta.pro primary industry

Process Analytical Instrumentation (Gas analyzers, spectroscopy, pH/ORP, conductivity) (IMAGAFAE)

akta.pro secondary industry

Sensors & Feedback Devices (Pressure, Flow, Position, Encoders, Transducers) (IMAHAGAK)

Keywords

• Inline process refractometers
• Concentration measurement instruments
• Black liquor divert systems
• Industrial brix density sensors
• Process control instrumentation

Headquarters

HQ city

Upton

HQ country

United States

HQ region

North America

Offices3 records

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

Supply Chain, Personnel, Operations, Technology or R&D, Marketing or Sales, Others

Revenue model

1. Process Refractometer Hardware Sales: Sale of inline process refractometers and sensors including Model 326 and Model 1022 systems. Hardware includes sensing heads, controllers, accessories like isolation valves, prism wash systems, and intrinsic safety barriers
2. Repair Services: In-house repair services for refractometer equipment including no-charge repair estimates. Repairs include inspection and written estimates, with option to approve or deny repair work
3. On-site Maintenance and Training: Emergency on-site maintenance services, preventative maintenance during outages, and on-site training services for customer technicians
4. Custom Application Quotation: Each industrial refractometer application is quoted separately based on unique customer requirements, process specifications, and industry needs

Pricing tiers

Go-to-market motion1 record

Distribution channels1 record

Marketing channels4 records

Core offering

Liquid Solids Control Inc. designs, manufactures, and services inline process refractometers that continuously measure liquid concentration and density in industrial process streams. Its core offerings are the Model 326 In-Line Process Refractometer (universal concentration/density sensor with touchscreen and 4-20 mA output) and the Model 1022 Black Liquor Divert System (a dual-refractometer safety system for pulp and paper recovery boilers), complemented by sapphire-prism sensing heads, insertion probes, green liquor probes, and accessories such as isolation valves, automatic prism wash systems, and intrinsic safety barriers. The company also provides in-house repair, preventative maintenance, emergency on-site service, and technician training for installed systems.

Product overview

Liquid Solids Control offers a portfolio of inline process refractometers and related measurement systems for industrial concentration/density monitoring. The core offerings consist of the Model 326 In-Line Process Refractometer (universal instrument sold across all industries) and the Model 1022 Black Liquor Divert System (specialized dual-sensor safety system for pulp and paper recovery boilers). These are complemented by a range of sensor types (In-Line Sensing Heads, Green Liquor Probes, Insertion Probes) and accessories (Gate Adaptor Isolation Valve, Automatic Prism Wash, Intrinsic Safety Barriers, Replaceable Baffles). The product line serves industries including Pulp and Paper, Semiconductor, Food/Beverage, Dairy, Chemical/Petro-Chemical, and Sugar, providing continuous in-line measurement of concentration using critical angle optical technology with sapphire prisms.

Differentiator

Problem solved

Functional benefit

Products and services

• Model 326 In-Line Process Refractometer A fully computerized two-piece optical/electronic process instrument that provides continuous in-line concentration and density measurement with an 8.4-inch touchscreen, Ethernet remote access, USB diagnostics, and isolated 4-20 mA output. Measures % by Weight, % Solids, Brix, Refractive Index, and Baume for industrial process automation customers across pulp and paper, chemical, food, dairy, sugar, beverage, and semiconductor plants.
• Model 1022 Black Liquor Divert System A specialized safety system for the pulp and paper market containing two independent refractometers and one Black Liquor divert controller that automatically diverts black liquor away from the recovery boiler when high solids are detected. Fully complies with BLRBAC recommendations for preventing smelt water explosions and is used by global pulp and paper mills.
• Refractometer Repair, Maintenance, and Training Services

Quantifiable outcome

• Energy efficiency improvement through precise process control to target points in Kraft process
• +3 more outcomes

Segments7 records

Ideal customer profiles2 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Integration1 record

Feature8 records

Partnerships

One partnership is on record.

• StahlcoreTechnology or IntegrationStahl provides intrinsic safety barriers for LSC's 326 sensors and probes, enabling safe operation in hazardous areas. LSC has designed a special box using 6 different channeled safety barriers intrinsically safe to the highest level. This partnership allows sensing heads to be located up to 500 feet (150 meters) away from electronic enclosures in hazardous locations.

Scale indicators4 records

Recent moves6 records

Expansion highlights4 records

Market position

Strengths4 records

Competitive moat5 records

Key risks6 records

Key highlights6 records

Customer concentration

Compliance2 records

Revenue estimate

Valuation estimate

Number of profiles

Profiles5 records

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Liquid Solids Control