Ultrahigh-recovery-rate waste water treatment process and concentrated water high-temperature reverse osmosis treatment equipment thereof

Abstract

The invention discloses an ultrahigh-recovery-rate waste water treatment process and concentrated water high-temperature reverse osmosis treatment equipment thereof. Specific to waste water which meets the reverse osmosis running requirement after pretreatment, the process is used for carrying out staged treatment according to different numerical values of total dissolved solids (TDS) concentration. The process comprises a raw water reverse osmosis (RO) process, a concentrated water reverse osmosis (CRO) process and a high-temperature reverse osmosis (HTRO) process which are performed in sequence. The concentrated water high-temperature reverse osmosis treatment equipment mainly comprises a concentrated water tank, a surface heat exchanger, a precision filter, a high-temperature reverse osmosis film device, an energy recovering device, a hyper-concentration waste water tank and a water purifying tank. After waste water is subjected to three times of reverse osmosis in sequence, the recovery rate of purified water can be greatly increased, the investment and running cost can be effectively lowered, and stable and safe running of a system can be ensured. As proved by testing, by adopting the invention, the weight of finally-separated concentrated water can be reduced to 2-5 percent of the total weight of the waste water, so that the investment and running cost of a subsequent waste water zero-drainage treatment system is greatly saved; and simultaneously, purified water which accounts for 95-98 percent of the total weight of the waste water is obtained, so that virtuous cycle of waste water is realized.

Description

technical field [0001] The invention relates to an advanced recovery treatment technology of industrial waste water, in particular to a waste water treatment process with an ultra-high recovery rate and concentrated water high-temperature reverse osmosis treatment equipment. Background technique [0002] In the recovery and treatment process of industrial salty wastewater, reverse osmosis, as the most advanced and effective desalination method in the world, has been widely used in various industries such as electric power, metallurgy, petrochemical, and electronics. Low recycling levels have become a common concern both inside and outside the industry. For example, some brackish water (surface river water, surface lake water, groundwater, circulating water in the plant, reclaimed water discharged from treatment, etc.) undergoes a series of pretreatments (including mixing, reaction, sedimentation, multi-stage filtration, softening, adsorption, desorption, etc.) Carbon, dosin...

AI Technical Summary

Problems solved by technology

However, due to the pressure of the reverse osmosis membrane, the mechanism of reverse osmosis of water molecules is multiple and uncertain, and it has not been well used since the design came out, especially in the treatment of power plant desulfurization wastewater and chemical wastewater. Stable, manifested in the rapid decline in the output of the reverse osmosis device, frequent chemical cleaning, serious fouling and clogging of membrane elements, etc.

Frequent chemical cleaning will not only lead to rising equipment maintenance costs and labor costs, but also pose a hidden danger to the stability and safety of the process system

[0007] The high-temperature reverse osmosis HTRO process has the characteristics of high pollution resistance, low operating pressure, high temperature tolerance, wide operating pH range, high separation of organic matter and insoluble salts, and can handle extremely high salt content (total dissolved solids 30000-80000ppm ) of high-concentration brine, but because it needs to use expensive high-temperature reverse osmosis membrane elements, and the matching pumps, pipelines, containers have high pressure ratings and corrosion resistance levels, so the manufacturing cost of the equipment is very high, and at the same time Also because of its relatively low reverse osmosis desalination rate (only 95%) under high temperature operation, the water quality of the produced water is relatively poor, which made it limited to a very small number of small reverse osmosis concentration occasions with high medium viscosity in the past. processing has not been able to be used

When zero discharge of wastewater is implemented, the purified water recovery rate of concentrated water reverse osmosis CRO and high-efficiency reverse osmosis HERO can only reach about 90%, so the amount of concentrated water that needs to be evaporated and crystallized is still large

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