Applications Terminology 

MACH provides quality-engineering design, equipments and services for air and water pollution control. Our products include Fume Scrubbers, Air Strippers, Distillation Towers, Tower Packing, Internals and various Fiberglass structures.


It is a process by which desired product is separated from a mixture of components. In chemical engineering, separation processes are conducted to produce chemical and biochemical products economically. Included are distillation, absorption, liquid-liquid extraction, leaching, drying, and crystallization as well as newer methods such as adsorption, chromatography and membrane separation.


In stripping, liquid mixtures are separated at elevated temperatures and ambient pressures, by contacting the feed with a vapor stripping agent. In distillation, the process of stripping concentrates the less volatile components in a liquid stream. A vapor recycle vaporizes (“strips”) the more volatile components from the liquid. To generate the vapor recycle, heat is supplied to vaporize a portion of the bottom stage liquid. This vapor recycle is termed boilup.


It is a process in which a liquid is used to assist or accomplish the collection of dusts or mists. The liquid is dispersed into the gas as a spray and the liquid droplets are the principle collectors for the dust particles. To find out more about this process, follow the link below:


It is a process of separating a mixture into two or more products that have different boiling points, by preferentially boiling the more volatile components out of the mixture. It involves multiple contacts between counter currently flowing liquid and vapor phase. Each contact called a stage, achieves separation of species through mass transfer followed by phase separation. Follow the link below, to find out more about distillation:


It is a process of concentrating the more volatile components in the vapor stream. Moreover, a process by which the light components are purified and the recovery of heavier component gets increased.

Heat Transfer

It plays an important role in separation processes. Thermal gradients present between two passing streams help make the separation or provide energy for the process to occur. Operations such as flash vaporization, evaporation, and drying make use of heat transfer to achieve the desired product. Some of the heat transfer equipment are heat exchangers, condensers, reboilers, and evaporators. Learn more about heat transfer in chemical processes, by following the links below:


It is a process of absorbing oxygen from air and there are three main types of aeration systems: mechanical, diffused and combined mechanical-and-diffused aeration system. They are used by industrial waste systems to treat variable organic loads. Aeration equipment employed by these systems has two major functions: mixing and oxygen transfer.


It is the removal of high volatile components from a relatively nonvolatile liquid. This separation is accomplished by continuous rectification. The volatile components are initially present in small amounts and needs to be reduced to zero concentration. This requires a column operating at total reflux.


It is a process of removing fine droplets of liquid from process and waste gas streams. Demisters or mist eliminators are devices that can remove entrained liquid from gas flow effectively.


It is used to regenerate the adsorbents, which include activated carbon, aluminum oxide, silica gel, and synthetic sodium or molecular sieves. Equipment consist of a cylindrical vessel packed with a bed of solid adsorbent particles through which the gas or liquid flows. Because regeneration is conducted periodically, two or more vessels are used, one desorbing while the other adsorbs. Regeneration occurs by one of four methods: vaporization of the adsorbate with a hot purge gas (thermal swing adsorption), reduction of pressure to vaporize the adsorbate (pressure swing adsorption), inert purge stripping without change in temperature or pressure and displacement desorption by a fluid containing a more strongly adsorbed species.


It is a unit operation recently developed for the control of gaseous emissions. Biofilters carry out biofiltration by using enzymatic catalytic oxidation, to completely break down biodegradable air pollutants to H20, CO2 and salts.


It is a process by which the desired substance gets transferred from one phase to another. The different types of extraction processes are liquid-liquid extraction and solid-liquid extraction (leaching). The primary purpose of the extraction process is to transfer the solute from the feed phase to the extract phase. Extraction can be achieved through fractional extraction, cross-current or cross-flow extraction and countercurrent extraction. Learn more about the extraction process, by following the link below:


It is one of the auxiliary operations that is necessary to the success of the key operations like chemical reactions and separation of chemical mixtures. When immiscible fluid phases are contacted, intimate mixing is used to enhance mass transfer rates so that a high degree of separation can be achieved rapidly.


Precipitation involves solutes that are only sparingly soluble. In a process known as reactive crystallization or precipitation, the precipitate is formed by changing pH, solvent concentration, or solution temperature, or by adding a reagent that reacts with the solute to produce an insoluble chemical.


It is the removal of moisture (either water or other volatile compounds) from solids, solutions, slurries, and pastes to give solid products. It also describes a gas mixture in which a condensable vapor is removed from a non-condensable gas by cooling and the removal of moisture from a liquid or gas by sorption. In designing the dryer equipment, of importance is the temperature at which the moisture evaporates. Check out the links below, to understand the drying process:


Condensers make use of condensing medium such as air, water or refrigerant to absorb heat from the vapor. The vapor loses heat to the condensing medium and reaches the saturation point where it condenses to a liquid.


In cases where inlet salt content is high, multiple stage countercurrent desalting system can be used. Reverse osmosis is used to desalinate and purify seawater, brackish water, and wastewater. Prior to 1980, multistage flash distillation was the primary desalination process. Reverse osmosis is an economical pressure driven process. An asymmetric membrane allows pressurized water to pass through at a high rate while almost preventing transmembrane flows of dissolved salts, organic compounds, colloids and microorganisms. To find out more about the desalting process, follow the link below:


The humidifying process is usually coupled with the heating process in many air conditioning systems. In a humidifying process, the air passes through a heat exchanger, and then through the humidifier where steam is sprayed onto the air stream. In this process, there is a simultaneous increase in the dry bulb temperature and the humidity ratio in the air. 


During a cooling operation, the temperature of the process stream is lowered, by passing it through a cooling system. One of the most widely used cooling process throughout the industries is evaporative cooling. It employs water to remove process heat, rejecting that waste heat into the environment. The classic cooling tower and the wet surface air cooler is where the evaporative cooling technology is applied today. Usually the water is cooled by exposing it to air. The degree of exposure of water surface to air determines the speed of the process.