Start a Industrial Gas Plant

   


(336).Start a Industrial Gas Plant


Industrial gas is a group of gases that are commercially manufactured and sold for use in industrial processes, such as steelmaking,oil refining, medical applications, fertilizer, semiconductors, etc.,. They may be both organic and inorganic, are produced by extraction from the air by a process of separation or are produced by chemical synthesis, and will take various forms such as compressed, liquid, or solid. 
 The most common industrial gases are:air gases - oxygen (O2), nitrogen (N2) and argon (Ar) rare gases - such as helium (He), krypton (Kr), xenon (Xe) and neon (Ne) and other gases like hydrogen (H2), carbon monoxide (CO), carbon dioxide (CO2) and nitrous oxide (N2O) ,chlorine (Cl2), hydrogen chloride (HCl) and sulphur dioxide (SO2) ,acetylene (C2H2), methane (CH4) and propane (C3H8).
In addition, there are many different mixtures of these and other gases to meet the needs of specific applications. The industrial and medical gases industry serves a very large number of customers in the whole community. Industrial gases are essential for almost all manufacturing. Large quantities of oxygen, nitrogen and argon are used in the steel and metal industry. Shipyards and the automotive industry use acetylene, propane, mixtures of fuel gases and oxygen for cutting and welding. Liquid nitrogen is vital in recycling plastics, packaging and scrap tyres. The chemical industry employs all major industrial gases as a raw material or for inerting. The other smaller market segment consists of cylinder gas and mixtures.
According to the Freedonia group, inc., a Cleveland-based industry research firm, world demand for industrial gases is forecast to increase 6.9% annually to $36.8 billion in 2011, with volume exceeding 300-bcm (billion cubic meters). Asia/pacific is the largest consuming region because of rapid growth in developing industrial markets, especially those of china and India.
Coming back to India, there are presently over 300 small & medium size plants and approximately 25 large tonnage plants all over the country. These gases are supplied through pipelines to captive customers in adjacent factories; in cryogenic transport tanks for bulk deliveries to long distance customers; or filled in cylinders.
The present annual turnover of the gas industry, excluding captive production is about Rs. 3,000 crores ($650 million). With increased industrialization, the demand pattern of industrial gases is also changing fast. Modern application in the food processing industry, agro industries, healthcare and technology are growing at a tremendous pace. This has driven the industry to adopt stringent quality control systems and an efficient distribution network.
Major players in India include BOC India, INOX Air Products Ltd., Jindal Praxair Oxygen Co. Ltd., Air Liquide India Holding P.Ltd., Aims Industries Ltd etc.
The Indian gas industry is growing at an average rate of 12 per cent per annum during the last couple of years, with the industrial oxygen growing consistently at 15-17 per cent per annum. The growth of industrial gas industry can be easily forecast on the basis of projections of the steel and other metallurgical industry. Steel demand is seen rising by 10% in the fiscal year to march 2011, helped by higher spending on infrastructure will continue to drive growth of the gas industry. Natural gas comprises 9 % of India's primary energy consumption and it will be 14% of energy mix by 2010. Demand for natural gas is also likely to increase at an average annual growth rate of 7.3%.Metals production and fabrication will continue to be the largest market for industrial gases, accounting for 31% of total demand in value terms in coming years. The second largest market will be the chemical processing/petroleum refining segment. The medical/healthcare market, though smaller in size, will be the fastest growing and record gains from the expansion of healthcare services in developing nations and rapidly increasing use of home healthcare respiratory therapies in advanced economics. Hydrogen is gaining prominence and most companies are striving to develop technologies that can efficiently exploit the potential of hydrogen. Increased use of natural gas will create an opportunity for higher production of argon and carbon dioxide. The Industrial gas industry has a very bright future in the coming years.

REPORT HIGHLIGHTS

• The global market for the industrial gas business was worth $63 billion in 2008. It decreased to an estimated $59 billion in 2009, but is projected to increase at a compound annual growth rate (CAGR) of 5.2% to $76 billion in 2014.
• Sales in the chemicals and refining-related processing market amounted to $22.7 billion in 2008, and decreased slightly to $22.4 billion in 2009, but are expected to reach $27.5 billion in 2014, for a 5-year (CAGR) of 4.1%
• The second-largest segment of the market, metal manufacturing and fabrication, was estimated to be worth $17 billion in 2008 and was expected to decrease to $14.5 billion in 2009. It’s projected to grow to more than $20 billion in 2014, for a 5-year CAGR of 6.7%.

Nitrogen Gas Plant Nitrogen plant/generator operating on PSA technology, consists of twin tower system filled with special grade of carbon molecular sieves (C.M.S). At a time, one tower keeps in production cycle and other in regeneration cycle. When compressed air passed through C.M.S. bed, the molecules of oxygen, moisture & other unwanted gases are adsorbed on surface of C.M.S. And the nitrogen which is not adsorbed by C.M.S comes out of adsorption tower and is collected in a surge vessel. For continuous generation of nitrogen, two adsorption towers are provided which are interconnected with auto change over valves controlled by a sequence programmer. When one tower saturates with oxygen the process automatically changes over to another tower and thus the nitrogen production is continuous.   Product Attributes Salient Features of N2 Gas Plants Flow rate 1 to 1500 Nm3/hr. Skid mounted units Easy installation Safe and economical Pure output Continuous supply Maintenance free N2 purity 95% to 99.9999 % Pressure Standard Dew point Up to (-80) deg. c   Flow Scheme for PSA Nitrogen Gas Generator Our gas generators are of optimum quality, durable and easy to handle. Our on site PSA nitrogen generators are custom made and can be adjusted to give the desired nitrogen quality for your process and application.   Purity of Nitrogen If you want pure Nitrogen, what you need is to select our PSA nitrogen gas generator. Nitrogen purity in the range of 99% to 99.9999% can be achieved through our nitrogen gas generators. Our PSA nitrogen gas generator produces raw nitrogen of 99% to 99.99% purity. By adding purification modules to this unit, nitrogen of 99.9999% purity can be achieved. Following are the generator models to produce different nitrogen purities: "MS” Model: This model is the simplest to produce nitrogen of a purity in range from 95% to 99% purity. However, if carbon molecular sieves quantity is increased, even 99.999% purity nitrogen can be produced from this model. But running cost would be higher in case of higher purity. Thus, this model is recommended for purity up to 99.9% only. This model is generally used to purging or Inertizing applications. “DX” Model: This model is commonly used in metallurgical industries for providing oxygen free nitrogen for heat treatment furnaces. Here, the oxygen is less than 1-ppm and but hydrogen is around 0.5 to 1% which is desirable as reducing constituent in most of heat treatment applications. “MS” models can also be converted into “DX” model by adding halladium deoxo reactor and dehydroation unit. “DX” model is also applicable in chemical as well electronic industries. “Copper-DX” Model: “Copper” DX model contains an extra nitrogen purification module based on copper deoxo catalyst. This model finds application in synthetic fiber, optical cables & electronic industries. Running cost of this unit is highest because it produces very pure nitrogen gas i.e free from oxygen and hydrogen as well. It is applicable where hydrogen contents are detrimental to the process. Oxygen Plants Pressure Swing Adsorption (PSA) technology relies on the selective adsorption phenomena of gas molecules under pressure on the surface of highly porous and efficient adsorbent. Here in oxygen generation, the adsorbent is zeolite based molecular sieve (Z.M.S). Process of PSA Oxygen Gas Generators In this system, when compressed air is passed through a adsorption tower field with Z.M.S, the molecules of oxygen, moisture & other unwanted gases are adsorbed on surface of Z.M.S and oxygen which is not adsorbed by Z.M.S comes out of adsorption tower. This oxygen is collected in a surge vessel. Two adsorption towers are used for continuous generation of oxygen gas, which are interconnected with autochange over valves controlled by Programmable Control Panel (PLC) in the control panel. After saturation of one tower with oxygen, the process automatically changes over to another tower resulting into the continuous production of oxygen gas for long. The Stages: In the first molecular bed, compressed air is fed in which nitrogen is trapped and oxygen flows out. When the first bed is filled with nitrogen, air flows into the second bed. When the second bed separates oxygen from nitrogen, nitrogen is vented out in the atmosphere in the first bed. Again the compressed air flow in to the first bed, the process continues and there is a constant flow of oxygen. Product Attributes In fact, the productivity of a PSA oxygen generator depends upon the requirement of oxygen purity. With a relatively small increase in feed air these generators can produce significantly more oxygen at 90% purity than it can at 95.4%. By means of a PLC or some other micro processor based controller, on larger generators it is practical for the users to change the swing cycles on timely basis. In fact, the purity and flow levels can also be selected and optimized based on changing demand variables. Acetylene Plants Acetylene's special property of giving bright light and intense heat when burnt with oxygen has made acetylene widely applicable in various kinds of industry, especially in metal welding and cutting, analysis in medical industry and instrument industry. Chemical use of acetylene is currently growing at the modest rate of 1.5 percent annually. It is becoming increasingly prominent as a raw material for a whole series of organic compounds, among them acetaldehyde, acetic gas, and acetic anhydride. This has resulted in high demand for acetylene thus, leading to high demand of Acetylene Gas Plants. Acetylene (C2H2), is known as one of the simplest and most significant chemical in the acetylene series. A compound of carbon and hydrogen, acetylene is a colorless, highly flammable gas that dissociates at normal to low pressures and needs to be stored in high-pressure tanks containing some porus material and acetone. It has active chemical property; it is easy to polymerize, synthesize and cause chemical reactions. Acetylene Gas Plant - Process Acetylene is manufactured by the reaction of water with calcium carbide and can also be produced by thermal cracking of hydrocarbons, or by partial combustion of methane and oxygen.  The plant consists of the following: Acetylene Generator: It consists of an agitator and its drive unit with several other things, like, flash back arrestor, safety valves drain system & the automatic control system. Condenser for cooling: To cool the acetylene gas produced by the generator, which is hot and have moisture and other gaseous impurities.  A Low Pressure Dryer:This dryer is charged with anhydrous carbide which absorbs the moisture in the gas.  High Pressure Dryer with three columns: The first one is filled with packing to avoid any void and ensure better mixing and the second and third are filled with anhydrous calcium chloride. Purifier: Which is a huge tanker, divided into two parts. Each part is charged with purifying mass which absorbs waste gases.  Ammonia Scrubber: An equipment for all the water-soluble impurities like ammonia.  Acetylene Compressor: which is a 3 phase machine, immersed in water filled tank. It avoids the pressurized gas to come in contact with air and make sure that all the components are continuously cooled.  An acetone Pump: Which is foe the purpose of charging acetone in cylinders. Filling Manifold: Have two headers fitted with non-return valves, one flash back arrestors, pressure gauge and manual isolation valves.  Controllers: An acetylene gas plants comes with numerous automatic controls, like, Temperature cum temperature alarm, pressure controls, level alarm, water inlet control.  Liquid Acetylene Plant Liquid Acetylene or dissolved acetylene is manufactured by 'Dissolved Acetylene Gas Plants' by using compressor to charge the acetylene in gas state into steel cylinder filled with porous material and solvent (acetone), to make acetylene gas dissolved in acetone solvent. The next step follows at the time of actual application, when acetylene gas is released from acetone solvent, producing the dissolved acetylene.  CNG Plant Since 1960s, CNG is recognized as a vehicle fuel alternative to oil-based gasoline and diesel fuel that reduces pollution of the air we breathe and also reduces. It is a natural gas compressed to a volume and density that is practical as a portable fuel supply. Compressed natural gas (CNG) as a vehicle fuel is the same clean and safe, natural gas that is used to cook food and heat homes. Natural gas contains less carbon than any other fossil fuel and, therefore produces less carbon Dioxide (CO2) when compared to any conventional vehicles. Its usage also results in significantly less carbon monoxide (CO), as well as less combustive organic compounds than their gasoline counterparts.  Compressed Natural Gas (CNG) is made by compressing purified natural gas, and is typically stored and distributed in hard containers. Mostly, a CNG station is created by connecting a fuel compressor to the nearest underground natural gas pipeline distribution system. The CNG Plant Process CNG is basically produced by pressing natural gas at 3,000 psi pressure. Compressed Natural Gas (CNG) is usually produced on the fueling station site with a compressor based system. Natural gas is transported through pipelines to refueling stations and there compressed at a pressure of 3,000 psi with the help of specially installed compressors that enables it to be loaded as gas cylinders for vehicles.  The process consists of drawing the natural gas from underground pipelines by the compressor. The composition of pipeline natural gas vary considerably depending on the time of year, pipeline demand, and pipeline system. It may contain impurities, like, oil, particulates, hydrogen sulfide, oxygen or water. Hence the modern day, quality CNG Plant system consists of facilities to address problems caused by them. Using LNG as the feedstock to make CNG eliminates or mitigates each of the above stated concerns as contains no water or any such impurity. This eliminates the concerns for corrosion, plugging of fuel lines, and the formation of hydrates. LNG is not even subject to compositional changes driven by the time of year, pipeline demand, or pipeline system and can be delivered as pure methane, which is actually the most desirable component of natural gas. Significant Innovation A new kind of CNG technology is being developed which promises lower costs and shorter scheduling time than either Liquefied Natural Gas technology or a pipeline transport. This technology may provide a unique solution to the development of distressed or stranded gas reserves and provides an alternative to associated gas re-injection.  Biogas Plants The Bio-Gas Plant produces gas from the raw materials of human excreta and cowdung. The residue obtained from the plant is used as the food of fish. It is a system to process livestock wastes into safe, high-quality, efficient organic fertilizer without exhausting greenhouse gases into the air. These gas plants also contribute to safe-keeping and clean environment by preventing bad odor and contamination of the underground. Furthermore, they are capable of generating electric power and hot water by processing methane gas which is produced during the fermentation process. Widespread use of the bio-gas plants could deliver a badly needed means of energy self-sufficiency, and the decentralized structure of the biogas plants means less need for expensive distribution of energy in rural areas. The Bio-Gas Plant Process A Bio-Gas Plant consists of two components: Digester also known as fermentation tank. Gas holder. Fermentation Tank : It can be best described as a cylindrical or cube-shaped tanker which is waterproof and comes with as inlet into which the raw-materials are introduced in the form of liquid. Gas Holder : It is an airproof steel container, which cuts off air to the digester and collects the gas thus generated, by floating like a ball on the fermentation mix. An ever-increasing number of these tanks are covered with a roof to collect as much biogas as possible. Bio-gas contains carbon dioxide and a slight amount of hydrosulfide as well as methane gas. Hydrosulfide is an obstacle for utilization of biogas, because it is corrosive. After desulfurising through biological method, biogas can be used for power generation. All large-scale biogas plants are controlled by an overall process control system and comes with various devices for measurement and safety purposes. One of the key features that is commonly found in almost every kind of Bio Gas Plant is that, the gas holder is equipped with a gas outlet, while the digester is provided with an overflow pipe in order to lead the sludge out into a drainage pit effectively. For biogas plant construction, the most significant criteria should be, the amount of gas required, and the amount of waste material that is available for processing purpose. Alternate Raw- Material To improve economy of bio-gas plants scientists have discovered other organic substances that can be used alongwith the manure. The examples of such substances are, fats, spice residues, market wastes, residues from food industry and many similar substances. The usage of these as raw material also improves the production level of Bio Gas Plants. The Bio-Gas Plant that is used to generate gas from this kind of feedstock involves the following steps :- Decomposition of organic matter contained in manure. Synthesis of acetic acid out of decomposed matter. Methane gas formation from acetic acid through the action of microorganism called methanogen. LNG Plants Natural gas in its liquid state, is called LNG, or liquid natural gas. Liquid Natural Gas (LNG) comprises of liquid hydrocarbons that are recovered from natural gases in gas processing plants, and in some cases, from field processing facilities. These hydrocarbons involves propane, pentanes, ethane, butane and some other heavy elements. LNG accounts for about 4% of natural gas consumption worldwide, and is produced in dozens of large-scale liquefaction plants. It is produced by cooling natural gas to a temperature of minus 260 degrees F (minus 160 Celsius). At this temperature, natural gas becomes liquid and its volume reduces 615 times. LNG occupies 1/600th the volume of natural gas at atmospheric temperature and pressure. The gas have high energy density, which makes it useful for energy storage in double-walled, vacuum-insulated tanks. The production process of LNG starts with, Natural Gas, being transported to the LNG Plant site as feedstock. After filtration and metering in the feedstock reception facility, the feedstock gas enters the LNG plant and is distributed among the identical liquefaction systems. Each LNG process plant consists of reception, acid gas removal, dehydration/mercaptan removal, mercury removal, gas chilling and liquefaction, refrigeration, fractionation, nitrogen rejection and sulfur recovery units The Process  The process through which Liquefied Natural Gas is produced consists of tree main steps, namely:- Transportation of Gas (feedstock) The best place to install the plant is near the gas source. The gas is basically transported through pipelines or by truck and barge. Pretreatment of Gas. The liquefaction process requires that all components that solidify at liquefaction temperatures must be removed prior to liquefaction. This step refers to the treatment the gas requires to make it liquefiable and includes compression, filtering of solids, removal of liquids and gases that would solidify under liquefaction, and purification which is removal of non-methane gases. And finally, Liquefaction of Gas. Features  There exists a vast number of natural gas liquefaction plants designs, but, all are based on the combination of heat exchange and refrigeration. The gas being liquefied, however, takes the same liquefaction path. The dry, clean gas enters a heat exchanger and exits as LNG. The capital invested in a plant and the operating cost of any liquefaction plant is based on the refrigeration techniques. Though, Liquefied Natural Gas can also be extracted from cryogenic hydrocarbon extraction and petro-chemical processes, but it requires careful consideration at these facilities to assure the process gas is liquefiable. Carbon Monoxide Plants There is very high demand for the high purity carbon monoxide (CO) in the chemical industry. It is the ideal material to produce polyurethane or polycarbonate. There are a large variety of Carbon monoxide sources available that includes the reforming gases from LPG, petroleum or coal and also as a by-product gas that is obtained from iron works. This plants utilize the sophisticated PSA process which separates and recover CO gas from methanol. Plants with large capacity such as from 150-200Nm3/H is being successfully operated today. Opreation of the plant is described here. Operation of a Carbon Monoxide Plant:It starts as the material gas is first fed into the adsorption tower, then the usual process of PSA cycle follows: Adsorption Purging Desorption Repressurization By repeating the above process the Carbon Monoxide gets generated. Figure below illustrates working of a 4-bed adsorption tower system, it must be noted that it is not compulsory to erect always four adsorption towers as when the CO's purity requirement is low, the system can be operated with lesser number of towers or stages in the process flow. Key Features of a Carbon Monoxide Plant employing PSA Process: Recovery Rate of CO: Around 90% Purity Rate of CO: Around 99% Application: Small to medium scale Cryogenic Gas Plants In the present market scenario, Cryogenic air separation has emerged as the most cost effective technology for larger plants and for producing very high purity oxygen and nitrogen. The USP of these plants is that it is the only technology that can produce liquid products. Cryogenic air separation is a traditional method of producing nitrogen and oxygen gases. The technology requires a large plant to cool air to several hundred degrees below zero in order to separate the component gases. The design choice of 'Gas Process Systems' depends upon the number of products required, like, whether one needs nitrogen or oxygen, both oxygen and nitrogen, or nitrogen, oxygen and argon. The other factors that influences the choice are the gaseous product delivery pressures, required product purities and should the products be produced in liquid form. There exists a large number of air separation systems that can be employed to manufacture Industrial Gas. Cryogenic air separation process is one of the most acceptable and popular process that is commonly used in large or medium scale plants to produce nitrogen, oxygen, and argon as gases and/ or liquid products. Almost all cryogenic air separations begin with a similar series of steps. However, the energy required to operate them depends on the product mix and required product purities. Some designs minimize capital cost, some minimize energy usage, some maximize product recovery, and some allow greater operating flexibility. The various steps involved in every kind of Cryogenic Production Process are : Filtering and Compressing air This is done by the multistage highly efficient air compressor and the Process Skid present in each plant. Condensed water is removed from the air as it is compressed and then cooled. Cooling The compressed air is then cooled to close-to-ambient temperature by passing through water-cooled or air-cooled heat exchangers. Removing contaminants The next step is removing the remaining water vapor and carbon dioxide. Cooling to cryogenic temperature Further heat transfer, in brazed aluminum heat exchangers, cools the air to cryogenic temperature (which is app -300 degrees Fahrenheit or 185 degrees Celsius). Distilling Distillation columns separate the air into desired products. This is basically done by a special kind of Air Separation Unit which commonly consists of upper & lower column and special exchangers. Warming gaseous products and waste The cold gaseous products and waste streams that emerge from the air separation columns are routed back through the front end heat exchangers. After this step we are left with the final product from a liquid Oxygen/Nitrogen that goes to the storage tank. Nitrogen and oxygen are then distributed to customers in liquid form using tanker trucks.