Updated: July 2002

1. Outline

NGK full-automatic moisture meter determines rapidly the moisture contained in sewage sludge, etc where appearance and property of the sample fluctuate.
The equipment is constituted by two units, including the sampling unit which is provided over a belt conveyor and collect the conveyed sludge automatically and the main unit which is provided on the conveyor site and automatically determines moisture of the sample fed from the sampling unit.
Input of measuring conditions, confirmation of measuring conditions and measured records can be carried out either by a field operation by using the CRT display on the main unit or by a remote operation by communication.

2. Performance and Specification

Precision; ca, ±1%
Measurable range; 5 -90%
Measuring Period; ca, 5-15min
Dimension of the main unit; W870×D800×H2,060
Power consumption; 1.5kW
Compressed air; 0.6Pa

3. Features

1) High precision; A high precision can be attained by using the direct heating loss method using an infrared lamp.
2) Rapid measurement; The drying period can be largely shortened with no scorch of the sample by the adoption of a three step infrared heating method controlled by a computer
3) Applicable for a wide range of cake moisture; The measurable range of moisture is wide by the computer-controlled drying, It can be applied for a sample conveyed intermittently on the conveyor by an automatic collecting device having a repeated poking mechanism and an ultrasonic sensor.
4) No pollution to the environment; It has a built-in activated carbon adsorption column and purifies the gas generated during drying before discharge.

4. Principle

1) It pokes the sample on the conveyor several times in a hollow tube to collect ca. 10g of the sample and feeds it on the sample dish in the main unit.
2) A specified quantity of the sample is sliced during feeding to enhance the dryness of the sample.
3) The moisture in the sample is evaporated by an infrared lamp and the moisture content is calculated from the difference of the weights before and after drying.
4) The temperature of the drying atmosphere and the change in the sample weight during drying are always measured to determine the optimum heating condition for drying by CPU.
5) It is air-cooled to prevent heat accumulation in the heating system during a continuous measurement.