Flow Measurement for Aluminium Slurry

下载 (2.8 MB)

Introduction

The slurry measurement is one of the most challenging application for magmeter. In this paper, Yokogawa's solution and expected benefit in aluminum slurry applications will be introduced.

Expected benefits

  • Stable and reliable process control in noisy and slurry applications maximize the productivity.
  • Longer life-time by robust design
  • Minimal downtime and maintenance work.

Application

  • In aluminum refinery plant, there are many tough applications to measure aluminum slurry, and corrosive chemicals.
  • Stable and accurate measurement in these severe processes condition and hash environments is the key to optimize the process control and the performance of plant operation.

Challenges

  • Abrasive aluminum slurry causes the output fluctuation and damage the liner and electrodes.
  • Heavy slurry noise may affect on the measurement accuracy and stability.
  • Shorter replacement cycle because of the mechanical damage caused by slurry.
  • High density red-mud covered on the electrodes requires frequent maintenance for the cleaning.

Yokogawa's Solution

ADMAG magnetic flow meter series delivers fit-for-purpose solutions for the difficult applications in mining industry.

Application Challenges Yokogawa's solution
Abrasive Slurry • Liner abrasion
• Slurry noise
ADMAG AXF
  • Dual frequency excitation (Enhanced dual frequency (<=200mm))
  • Ceramic Liner (<=200mm)
  • PFA liner with metal hat (>200mm)
High consistency adhesive slurry fluids Liner and electrodes are insulated by adhesion ADMAG CA (<=200mm)

ADMAG AXF Solutions

Flow measurement for aluminium slurryADMAG AXF's dual frequency excitation has the advantages of both the high and low frequency meters. Dual frequency excitation provides, good zero stability, accuracy of 0.35%, 0.2% as option of reading and immunity to slurry noise. Further, the "Enhanced Dual Frequency Excitation Method" is optionally introduced in the ADMAG AXF to cope with more difficult application such as high concentration slurry measurement.

AXF's new Enhanced Dual Frequency option provides an even higher excitation frequency of 165Hz for maximum slurry noise reduction when needed, without sacrificing zero stability.

Non-retained liners (extruded liner), which are commonly used in conventional meters, are susceptible to failures as a result of vacuum conditions that can be created due to a pump or valve failure. In addition, meters that have extruded liners generally have a shorter life due to the aggressiveness of the chemicals used. Yokogawa uses an injected molded PFA liner with a retaining grid. This retaining grid plate, used to reinforce the PFA liner, acts like rebar in concrete. This rugged construction holds the liner in place and prevents the liner from caving in due to vacuum conditions. The thickness and durability of the injection molded PFA liner provides a flow tube that is capable of handling the most severe applications.

The ADMAG AXF magnetic flow meter introduced fluid adhesion level diagnosis which always monitors the level of insulating material buildup on the electrodes, which enables maintenance timing can be recognized. In addition, with the utilization of ADMAG AXF's replaceable electrode type flowtube, electrodes can easily be removed and cleaned without removing flowtube from piping.

ADMAG-magnetic-flowmeter

ADMAG CA capacitance type magnetic flow meter with mirror finished liner

ADMAG CA and ADMAG AXF (Remote type)In red mud application, pregnant Liquor (caustic base) which quickly forms a thin hard insulating layer on the pipe walls. This coating can not be removed in-line by either chemical or mechanical means. Hence the conventional electrode type magnetic flow meter would stop the operation once coated, because the meter to be removed and the coating was manually scarped from the walls. As the actual example of an aluminum plant, the maintenance period that conventional electrode Type magnetic flow meter needed in every 2-3 months could be extended to every 12-18 months with electrode-less ADMAG CA that can continue the operation even once coated. The build-up rate of red mud was well known by customer. And the reduction in flow area can be calculated in the DCS and used to correct the measured flowrate as indicated in the below picture.

Reduction in Flow Area

行业

相关产品&解决方案

ADMAG CA系列

ADMAG CA电磁流量计凭借陶瓷管外部设置的电极板,通过管道电容获取电动势。此外,流量计采用了一种卓越的高频励磁方式,使低电导率流体的噪声明显降低。

电磁流量计

横河电机在磁流量计方面的经验已经有数十年了。我们的磁流量计为大多数地区的工业用途提供了灵活的配置。

×

Have Questions?

Contact a Yokogawa Expert to learn how we can help you solve your challenges.

置顶
WeChat QR Code
横河电机(中国)有限公司
WeChat Recruiting QR Code
横河电机中国招聘