CN104445777A - Multi-effect evaporation condensed water recycling method - Google Patents

Abstract

The invention discloses a method for recycling condensed water from a multiple-effect evaporation process, including: returning primary condensed water to the boiler for reuse; using part of the secondary condensed water as pump cooling water, part of the water as boiler replenishment water after filtration, and a small part as domestic water. This method allows the multiple-effect evaporation process to have substantially no sewage discharge, and the equipment modification is simple, the investment is small, and the energy-saving and environmental protection effects are good.

Description

Multi-effect evaporation condensed water recycling method

technical field

The invention relates to a method for recycling condensed water, in particular to a method for recycling condensed water of multi-effect evaporation.

Background technique

In the chemical production in the Qaidam Basin, general enterprises adopt the method of discharging waste water such as condensed water produced by multi-effect evaporation, which not only increases the discharge volume, but also has a great impact on the external environment, and also increases the production cost of the enterprise , Increase the water burden on the Qaidam area, which is already short of water. With the continuous development of salt lake chemical industry, the water consumption of enterprises is increasing. Water conservation, rational use of water, and multiple uses of one water have become issues of great concern and attention to all production enterprises.

In most cases, the steam transfer process, the heat exchange process and the condensate transfer process do not generate pollution. Therefore, the condensed water meets the water quality requirements of boiler water without pollution, and can be directly used as boiler water. In addition, due to the high temperature of condensed water, it is usually in the range of 60-80°C, and in some cases it can reach above 80°C. Therefore, condensed water contains a large amount of residual heat, which should be a factor that must be considered in the comprehensive utilization of waste water in today's energy shortage.

Contents of the invention

The purpose of the present invention is to provide a method that can comprehensively recycle and utilize the condensed water of multi-effect evaporation, which is applied in the field of chemical production.

The purpose of the present invention is achieved by the following technical solutions:

The multi-effect evaporation condensate recycling method includes two parts:

(1) The steam generated by the heating boiler enters the first-effect heating chamber to heat the feed liquid. After heating, the primary condensed water is generated through the surface condenser and enters the primary condensed water tank. The primary condensed water is pumped into the primary-effect preheater through the condensed water pump After preheating the first-effect feed, it flows into the boiler make-up water pool, and then returns to the boiler as boiler water for reuse;

(2) The condensed water from the second-effect heating chamber enters the surface condenser to flash, and the unevaporated part combines with the condensed water produced by the surface condenser to form the secondary condensed water and enters the secondary condensed water tank together, and the condensed water pump transfers the secondary condensed water The condensed water enters the second-effect preheater to preheat the first-effect feed material and enters the cooling water pool to cool down. After the temperature drops to a certain level, it enters the cooling water pool. Part of the recovered water in the cooling water pool is used for cooling water of each pump and recycled to the cooling water tank For the water pool, the excess part is stored in the waste water pool. After being filtered by the filter, the waste water in the waste water pool can be sent to the boiler make-up water pool for boiler water replenishment. Part of the water in the boiler make-up water pool can also be used as bath water, and the bath waste water is recycled to the waste water pool to form water cycle.

Compared with the prior art, the present invention has the following advantages:

1. Multi-effect evaporation is an equipment device that uses low-pressure steam to operate in a sealed manner. During operation, a condensed water recovery device is added to recycle and reuse the condensed water that was originally discharged, which can reduce the external discharge. The recovery rate reaches 80%, reaching The purpose of preventing environmental pollution and saving energy;

2. Save water resources and improve the desertification of the Qaidam Basin;

3. Saving production costs, enterprises can reduce water purchase costs and waste water treatment costs.

Description of drawings

Fig. 1 is a flow chart of the method of the present invention.

Detailed ways

Below in conjunction with accompanying drawing, technical scheme of the present invention is described in further detail:

As shown in Figure 1, the multi-effect evaporation condensate recycling method includes two parts:

(1) 1.0MPa steam evaporated from the boiler enters the first-effect heating chamber to heat the feed liquid. After heating, the primary condensed water is generated through the surface condenser and enters the primary condensed water tank. The primary condensed water is pumped into the primary-effect preheating through the condensed water pump After preheating the first-effect feed, it flows into the boiler make-up water tank, and then returns to the boiler as boiler water for reuse;

The condensed water from the two-effect heating chamber enters the surface condenser for flashing, and the non-evaporated part combines with the condensed water produced by the surface condenser to form secondary condensed water and enters the secondary condensed water tank together, and the secondary condensed water is pumped by the condensed water pump After entering the second-effect preheater to preheat the first-effect feed material, it enters the cooling water pool to cool down. After the temperature drops below the surface temperature of each working pump, it enters the cooling water pool. Part of the recovered water in the cooling water pool is used for the cooling water of each pump and recycled. To the cooling water pool, the excess part is stored in the waste water pool. After being filtered by the filter, the waste water in the waste water pool can be sent to the boiler make-up water pool for boiler water replenishment. Part of the water in the boiler make-up water pool can also be used as bath water, and the bath waste water is recycled to waste water The pool forms a water cycle.

Claims (1)

1. multiple-effect evaporation condensation Water Sproading Application way, is characterized in that described method comprises the steps:

The steam that heating boiler produces enters an effect oven heats feed liquid, produce a water of condensation through surface condenser after heating and enter in a condensate water pot, water of condensation is squeezed into after an effect preheater preheats one imitates charging by condensate pump and flows into boiler replenishing water pond, and then return boiler and re-use as boiler feed water;

Two effect heating chambers water of condensation out enters surface condenser shwoot, the water of condensation that its unevaporated part and surface condenser produce is combined into together with time condensation water and enters time condensation water pot, by condensate pump time condensation water squeezed into and enter cooling pond after two effect preheater preheats one imitate charging and cool, drop to until temperature and to a certain degree afterwards enter cooling basin, partially recycled water in cooling basin is used for each pump water coolant and is recycled to cooling basin, flap portion goes wastewater disposal basin to store, waste water in wastewater disposal basin can go to boiler replenishing water pond for boiler replenishing water after filter filters, part water in boiler replenishing water pond also can be used as publilc baths water, publilc baths waste water is recycled to again wastewater disposal basin and forms water cycle.