Industrial vacuum evaporators for wastewater treatment

At Condorchem Envitech we design and install vacuum evaporators for industrial wastewater treatment. Industrial water evaporators have proven to be one of the most efficient solutions for the management and reuse of wastewater. Furthermore, they are highly effective in recovering raw materials and by-products from a wastewater stream in all types of industrial activities.

Condorchem Envitech's vacuum evaporators deliver constant innovations and solid engineering. We customize every industrial evaporator to provide more efficiency and durability to our customers than any other wastewater equipment manufacturer.

Industrial vacuum evaporators are the best technology for implementing a zero liquid discharge system, where wastewater is transformed into two streams, one containing solid waste with reusable resources (mainly raw materials and by-products) and another one with high quality water, which can be reused. We can deliver a zero liquid discharge system that will allow your company to achieve the following goals:

• Reuse 98% of the water
• Recover valuable raw materials and by-products dissolved in the water
• Minimize the final sludge to be managed

As mentioned above, we can also provide you with a customized engineering solution for your wastewater treatment needs, designing and installing a complete wastewater treatment and resources recovery plant if that’s what’s required.

The Condorchem Envitech Vacuum Evaporator range covers the three main types of equipment, which have a robust and simple operation, occupy little space and constitute clean and safe technology. In addition, all equipment is highly automated, requiring minimal supervision.

• Heat pump vacuum evaporators.
• Mechanical vapor recompression vacuum evaporators.
• Multiple-effect vacuum evaporators.
• Crystallizers.

• Minimization of the waste volume to be managed
• Significant reduction in waste management costs
• Promoting the re-use of a significant part of the liquid effluents
• Possibility of implementation of a zero discharge system
• Fulfillment of the current regulations on discharge of effluents
• Reduction of the need to store large volumes of waste
• Reduction in greenhouse gas emissions when transporting the waste
• Reduction in the consumption of mains water by re-using treated water
• Absence of reagents (except for antifoam in some cases)

• Oily emulsions, coolant fluids, mould release agents
• Purging of compressors, water from washing floors
• Water from washing tanks and reactors (in the chemical, pharmaceutical, cosmetic and perfumery industries)
• Working and wash baths in galvanic processes and surface treatments
• Penetrating liquids
• Graphic arts waste (e.g. cleaning water and paint)
• Water treatment plant reject (e.g. reverse osmosis and demineralizers)
• Leachate from municipal solid waste dumps
• Digestate from biogas generation plants
• Food and beverage industry
• Pickling industry
• Energy generation
• Paper, minerals and extraction industries

Vacuum evaporators, also know as wastewater evaporators, are one of the most effective technologies for the minimization and treatment of industrial wastewater. The technology is clean, safe, very versatile and has a very low management cost. In many cases, it can also lead to a treatment system with zero discharge.

Vacuum evaporation is one of the most competitive and efficient techniques for treating aqueous effluents when conventional techniques are not effective or feasible. It transforms waste effluent into two streams, one of concentrated waste and another of high quality water. The evaporators work under vacuum, so the boiling temperature of the liquid effluent is lower; thus saving energy and improving efficiency.

Waste water evaporation by zero discharge technology

Wastewater evaporators are a key technology for implementing a zero discharge system, where waste effluent is transformed into solid waste and high quality water, all of which can be reused.

Depending on their different uses or geographical criteria, vacuum evaporators receive different names: e.g. vacuum distillers, vacuum concentrators, water evaporators or industrial evaporators.

The following can be found for the effluent heating system:

Heat pump

Operation of this industrial evaporator is based on the refrigeration cycle of gas contained in a closed loop. The refrigeration gas is compressed by a compressor, as a result of which its temperature and pressure increase. It then circulates through the heat exchanger of the evaporator itself, heating the feed. As the system operates under vacuum, the boiling temperature is around 40 ºC.

The refrigeration liquid leaves the evaporator’s exchanger and is decompressed and cooled using an expansion valve. Passage through a second heat exchanger (the condenser) causes the vapor formed in the evaporator to condense and its temperature to increase immediately prior to passing through the compressor again, thus repeating the cycle.

The same refrigeration fluid allows the feed to be evaporated and the vapor generated to be condensed, therefore the system does not require any other heating or refrigeration source. This means that the process is highly advantageous from an economic and management viewpoint.

Mechanical vapor recompression

Operation of this industrial evaporator is based on the refrigeration cycle of gas contained in a closed loop. The refrigeration gas is compressed by a compressor, as a result of which its temperature and pressure increase. It then circulates through the heat exchanger of the evaporator itself, heating the feed. As the system operates under vacuum, the boiling temperature is around 40 ºC.

The refrigeration liquid leaves the evaporator’s exchanger and is decompressed and cooled using an expansion valve. Passage through a second heat exchanger (the condenser) causes the vapor formed in the evaporator to condense and its temperature to increase immediately prior to passing through the compressor again, thus repeating the cycle.

The same refrigeration fluid allows the feed to be evaporated and the vapor generated to be condensed, therefore the system does not require any other heating or refrigeration source. This means that the process is highly advantageous from an economic and management viewpoint.

Multiple-effect

This technology comprises a series of mutually connected evaporators in which the vacuum steadily increases from first to last. This means that, in principle, the boiling temperature decreases, thus allowing the vapor generated in an evaporator (or effect) to be used as heating fluid in the following effect.

Its main advantage with respect to a single evaporator is the saving in both heating fluid and refrigeration fluid. This is one of the economically most competitive options for treating high flows.

Industrial application of evaporation

Vacuum evaporation is a simple process of high energy efficiency, i.e. low energy consumption and it is practically maintenance free. Normally, evaporation is preceded by other concentration technologies, such as reverse osmosis, for treating large volumes of waste water.

Evaporation in vacuum: The basic operation is very simple and is based on bringing the effluent to its boiling point, which is around 40°C when working under vacuum conditions. When the effluent begins to boil in the evaporator boiler tank, the steam condenses and is withdrawn from the system as more effluent is fed into the boiler tank. The effluent must be preheated before being fed for the evaporation process to continue. The technology used to pre-heat the effluent before reaching the tank constitutes the main difference between the different types of vacuum evaporator.

Treated water (distilled) that has been extracted from the liquid waste is of high quality and can be recycled in the plant for various applications (e.g. production and refrigeration); thus reducing the consumption of drinking water.

The application of industrial evaporation technologies for treating industrial liquid waste where it is produced has a series of advantages. Firstly, the waste can be minimized by concentration, thus significantly reducing its management cost. In some cases, it is possible to evaluate the concentrate itself for possible re-use in the same process or in alternative applications. Minimization at the point of origin also reduces the need for storage of large volumes of hazardous waste in industrial sites, and reduces the risk of spills caused by accidents during the transport of liquid waste. Finally, it contributes to a reduction in greenhouse gas emissions produced when transporting the waste.

Vacuum evaporators are characterized by concentrating with low power consumption, dissolved liquid or solid products. The concentrated product can become the final product of the production process or a by-product to be reused or recycled.

This procedure, under vacuum conditions, achieves a double goal. On the one hand, the product is not subjected to high temperatures, a critical fact when it comes to thermolabile substances (vitamins, proteins, hormones, etc). On the other hand, while the pressure decreases, the water boiling temperature is also reduced. This event enables water evaporation without consuming excess power.

Vacuum evaporators are suitable to concentrate a product without subjecting it to high temperatures, either because it denatures, deactivates or loses most properties. This is the case for most products in biotechnological industries (enzymes, vitamins, hormones, etc), food industries (concentrated juices, sweeteners like sugar and stevia, etc.) and pharmaceutical and chemical industries.

Condorchem Envitech offers “turnkey” solutions in vacuum concentration projects. We design, build and install vacuum concentration plants and have a wide range of concentrators to provide the most efficient solution in each particular case.