Ammonium sulfate crystal drying technology

1. Overview of ammonium sulfate crystal drying scheme

1.1. Ammonium sulfate crystal drying system. The whole process is that the ammonium sulfate solution is first crystallized in the MVR device, then dried by the centrifuge, and then enters this drying device for drying. After drying, it enters the ton bag packaging. The drying device adopts airflow drying, steam heating, and bag dust collector dust removal. The device includes ton bag packaging. This system can dry ammonium sulfate crystals with a moisture content of 7% to less than 0.5%, and can process 1400Kg of materials per hour; the process pipeline fittings and valve materials are 316L stainless steel, which meets the American standard series pipeline and flange standards.

1.2. Tetrasodium ethylenediaminetetraacetic acid (NAX for short) filter cake drying system. The process flow is that the filter cake-like wet material passes through the airflow drying device to dry its remaining moisture, and then the NAX solid ton bag is packaged. This system can dry NAX wet materials with a moisture content of 30% to less than 0.8%, and can process 700Kg of materials per hour; the control system adopts DCS centralized control; it can realize automatic control, including temperature, liquid level, pressure, flow, etc.; all rotating equipment can realize DCS start and stop, and large rotating equipment such as fans and pumps can realize on-site start and stop.

2. Principle of ammonium sulfate crystal drying scheme

Adopting the principle of instant drying, the rapid movement of hot air is used to drive the wet material and suspend the wet material in the hot air, which strengthens the entire drying process and improves the rate of heat and mass transfer. The non-bound moisture of the material dried by air flow can be almost completely removed (for example: the moisture content of the feed of starch and other materials is ≤40%, and the finished product can be 13.5%), and the dried material will not deteriorate, and the output can be significantly improved compared with the drying of general dryers, and users can achieve higher economic benefits in a short period of time.

3. Advantages of ammonium sulfate crystal drying scheme

3.1. High drying intensity and low equipment investment: The processing capacity of airflow drying equipment is the largest, and the evaporation capacity ranges from 50kg/h to 2000kg/h, while the equipment volume is small and the investment is low, which is unmatched by other drying equipment.

3.2. High degree of automation and good product quality: The airflow drying process is carried out entirely in the pipeline, and the drying time is extremely short (only 0.5-2 seconds). Therefore, automation can be achieved, the product does not come into contact with the outside world, the pollution is small, and the quality is good.

3.3. Complete equipment supply and free choice of heat source: The basic model consists of an air filter, a heater, a feeder, a drying tube, a fan, and a cyclone separator. Users can add dust collectors or other auxiliary equipment as needed.

3.4. In terms of heating method selection, airflow drying equipment has greater adaptability. Users can choose steam, electricity, thermal oil, or hot air furnace heating according to the conditions of their region, and can also choose according to the heat resistance temperature (or hot air temperature) of the material: steam heating can be selected when ≤150℃; electric heating (or steam heating, electric compensation or thermal oil heating) when ≤200℃; coal-fired hot air furnace when ≤300℃; oil-fired hot air furnace when ≤600℃.

The drying time is short, suitable for heat-sensitive materials, the finished product does not come into contact with the outside world, and the quality is good;

3.5. The equipment is provided as a complete set, and the heat source can be selected from steam heating or coal-fired, oil-fired, gas-fired hot air furnaces, etc.

3.6. Basic airflow drying equipment, suitable for loose, low-viscosity materials, and finished products are granules and powders. This process diagram shows negative pressure airflow drying, and users can choose a positive pressure drying method according to product characteristics.