Wednesday, July 29, 2020

Anderson Greenwood Instrument Valve Solutions

Anderson Greenwood Instrument Valves
TESCOM Anderson Greenwood Instrumentation serves many industries and applications. The product line includes a comprehensive range of isolation valves (including root and gauge models), instrument manifolds (for pressure, level and flow measurement), and purpose-designed Instrument Enclosure Systems.

Products include:
  • Hand Valves
  • Gauge Valves
  • Primary Isolation Gauge Root Valves
  • Pressure Manifolds
  • Flow and Level Manifolds
  • IntelliMount™ Systems
  • Saddlemount 
  • Keyblok Manifolds 
  • Monoflange
  • Instrument Protection Systems
  • Modular Mounting Systems
  • ACCU-Mount™ Systems

For more information, contact Piping Specialties, Inc / PSI Controls. Call them at 800-223-1468  of visit their website at https://psi-team.com.

Monday, July 20, 2020

Refractometer Application in Kraft (Sulphate) Pulp Process: Digester Washing Zone and Blowline

Refractometer Black Liquor

Introduction

The first operation in the Kraft pulping process involves the extraction of cellulose from wood by dissolving the lignin that binds the fibers together. This is done in a strongly alkaline solution.

This process is known as cooking. After the wood pulp is obtained, it is washed and bleached to obtain the fibrous product.

To optimize the pulp chemical consumption and water usage, the black liquor concentrations have to be measured before and after washing.

Application

Incoming wood is debarked and chipped to an optimal size to minimize fibre damage, and to maximize the impregnation with the cooking liquor. The chips and the cooking liquor are fed into a large vessel known as digester. The pulping reaction takes place under pressure and at a high temperature.

After cooking, the pulp passes through a blow line to the blow tank and then to a washing section. The diffuser washers separate the black liquor from the fibers by washing them with a washing liquor or water. The products from the fiber line are a clean pulp, and a diluted black liquor known as weak liquor.

The washed pulp is then screened before it is sent to the bleaching plant, and the weak black liquor passes from the washing section to the chemical recovery process.

Instrumentation and installation

The K-Patents SAFE-DRIVE Refractometer PR-23-SD measures in real-time the Total Dissolved Solids (TDS) content in black liquor.

K-Patents PR-23-SD
The K-Patents refractometer is installed in-line in different points after the digester. TDS measurement
in the blow pulp suspension after the digester enables monitoring of the diffuser operation. Together with other measurements (e.g. filtrate and flush liquor) this provides the mill with the ability to control the performance of the washing zone in the digester. In addition, TDS measurement in the blow line allows the performance of the digester to be monitored, ensuring that it yields the correct concentration. The combination of these measurements facilitates continuous calculation of the mass balances of the digester.

The refractometer’s measurement is unaffected by bubbles, particles, consistency, flow, ion changes, pH, temperature, pressure, color or turbulent flow. The measurement surface is periodically cleaned using an integrated and automatic prism cleaning system.

The K-Patents PR-23-SD 

Black liquor concentration measurement with the SAFE-DRIVE process refractometer helps to increase washing efficiency, obtain a consistent pulp quality, reduce bleaching chemical consumption and environmental load, and increase evaporation efficiency.


For more information, contact PSI Controls (Piping Specialties, Inc.). Call them at 800-223-1468 or visit their website at https://psi-team.com.

Thursday, July 16, 2020

An Innovative and Unique Solution for Measuring Dry Gas Flow in Wet Gas Environments

Kurz Wet Flow

The Problem - Reading Dry Gas Flow in a Wet Gas Environment


Irrespective of any single manufacturer's claim, daily and seasonal temperature changes in wet gas environments cause erratic high flow readings in standard thermal flow meters. With standard thermal flow meters, as the flow flow temperature decreases, more water condenses out of the gas causing the standard thermal flow meter to misread the water contacting the sensor as dense air. Within an active condensing gas flow, the low overheat (less than 50°C) of standard flow meter products make them incapable of accurately reading the dry gas flow within a wet gas environment.

Kurz Instruments Develops a Practical Implementation of the Leidenfrost Effect to Overcome the Problem


Leidenfrost Effect
The Leidenfrost Effect, named after 18th Century scientist Johann Gottlob Leidenfrost, is a phenomena that happens when liquid contacts a surface significantly hotter than the liquid’s boiling point.  A vapor layer is created between the liquid and the surface that keeps the liquid suspended, delaying the rate of evaporation. 

Kurz Instrument developed an innovative solution. By maintaining a high signal-to-noise ratio and a high sensor overheat, mist particles vaporize on impact with the heated sensor. Thus, by employing the Leidenfrost Effect, the leading edge of larger droplets vaporize to steam, which diverts the remaining water around and away from the heated sensor. The unique design of the WGF allows it to accurately monitor the dry gas component in a wet gas flow regardless of changing condensation levels.

The Kurz WGF flow meter for condensing gas environments includes features that allow them to outperform all other currently available thermal mass flow meters. Kurz was the first thermal mass flow meter manufacturer offering accurate and reliable condensing gas flow measurements. Their unique design centers around a high 300°C sensor overheat capability. The design also provides sensor overheat protection at zero flow through the incorporation of a unique temperature control and power limiting design. As a result, the Kurz WGF is not affected by water droplets in the flow stream. This unique technology establishes Kurz flow meters with WGF technology as the only thermal flow devices suitable for biogas and condensing gas environments found in digesters, landfills, animal feeding operations, mining, and wet stacks.

To learn more about The Leidenfrost Effect and how it applies to Kurz flow meters, visit this page.


To learn more abount Kurz Instrument products, call PSI Controls (Piping Specialties, Inc.) at 800-223-1468, or visit their web site here - https://psi-team.com.