Three Effect Evaporative Crystallization applied in Pesticide Wastewater industry Sodium Chloride
What is the MEE(Multi-effect Evaporation) System?
The multi-effect evaporator system is a system in which multiple single-effect evaporators are connected in series to achieve continuous evaporation. Since evaporation is a process that consumes a large amount of steam to generate secondary steam, in order to make full use of the waste heat of steam, generally the previous secondary steam is introduced into the next effect as a heat source. This maximizes energy utilization efficiency while ensuring evaporation.
The selection of the number of stages of the multi-effect evaporator depends on various factors such as the specific material properties, the concentration of the incoming and outgoing materials, the temperature, and the energy consumption cost. Generally speaking, more stages will result in lower steam consumption. We are also committed to providing multi-effect evaporators and solutions suitable for various materials.
Material process
(1) The raw material is delivered to the front primary preheater by the feed pump through the electromagnetic flowmeter, and then enters the top of the primary effect heater through the liquid distributor for primary falling film evaporation and concentration;
(2) The first effect concentrated liquid is transported to the top distributor of the second effect heater by the first effect bottom material circulating pump for secondary falling film evaporation concentration.
(3) The second effect concentrated liquid is transported to the top distributor of the third effect heater by the second effect bottom material circulating pump for third times of falling film evaporation concentration;
(4) Third effect concentrated liquid discharge, according to the online detection of the hydrometer, real-time detection of the material concentration, if the material concentration reaches the set requirements, it will be interconnected with the discharge valve to open the discharge valve and transport the material to the finished product tank, otherwise, it will open the material circulation valve to make the material recycle into the evaporator again for re evaporation.
Steam process
The raw steam enters the primary effect heater for heating evaporation concentration: the secondary steam generated by the primary effect heats the secondary effect, and so on. The secondary steam generated by the third effect enters the end condenser for condensation cooling, and the condensate water is discharged by the condensate pump.
Condensate process
The condensate water produced by the primary effect preheating the materials through the water transfer pipe at the bottom of the shell, to save the consumption of raw steam;
The condensate water produced by the secondary and third effect is discharged by the condensate pump, and the discharge has reached zero pollution. The non condensing gas is connected to the end condenser by the non condensing gas pipe and discharged by the vacuum pump.
Technical parameters of falling film evaporator
| Type | Single effect | Double effect | Three effect |
| Evaporative capacity (kg/h) | 300-2000 | 1200-4000 | 3600-15000 |
| Feeding material density % | According to material | ||
| Discharge material density % | According to material | ||
| Steam pressure | 0.5-0.8 | ||
| Steam consumption / Evaporative capacity(with heat pressure pump) | 0.65 | 0.38 | 0.28 |
| Evaporating temperature | 45-90 | ||
| Sterilizing temperature | 90-110 | ||
| Cooling water consumption / Evaporative capacity (inlet 20°C, outlet 40°C) | 28 | 11 | 8 |
| Note: we can design custom product according customer's requirement. | |||
Working principle drawing
Our production capability and client site
