Instrumentation and gas analysis for chemical industry

In chemical plants, gas, temperature, flow and pressure measurements are a top priority for efficient energy management, process reliability and reduced gas emissions. 

Choosing reliable measurement equipment is essential to ensure the service life of installations and to optimise the various technological processes used in refineries, ethylene, CVM, butadiene rubber and ammonia production plants.

Chemical and petrochemical processes

Oil refining (naphtha crude oil) → Manufacture of petrochemicals → Manufacture of chemicals (derivatives)

Refineries

Petroleum refining is the industrial process by which crude oil is refined into fuel oil and various petrochemicals. An oil refinery consists of facilities that manufacture products from raw materials and utilities.

The process begins by heating crude oil to a temperature of 350°C in a heating furnace. This heated oil is then channeled into a distillation tower up to 50 meters high. Within this distillation tower, a critical operation takes place: the separation of the oil into different fractions. These fractions are defined by specific substances: naphtha, kerosene, diesel and heavy fuel oil. The key to this separation lies in the differential boiling point of each fraction.

Ethylene plant

An ethylene plant is the facility where hydrocarbons are cracked and separated from naphtha or other feedstocks to produce primary petrochemicals. Repeated distillation of refined oil or gas yields ethylene, propylene and a variety of other petrochemical products. The production capacity of the entire plant (or industrial complex) depends on ethylene, as it serves as the raw material for producing the derivatives listed below.

Production of monomeric vinyl chloride CVM

Monomeric vinyl chloride (CVM) is mainly used for the production (by polymerization) of polyvinyl chloride (PVC). CVM is organic gas, colorless at room temperature. It is a very volatile compound and poorly soluble in water.

There are two methods for producing monomeric vinyl chloride CVM:

• Direct chlorination
• Oxychlorination.

Both of these methods are used in most CVM plants. Both processes use dichloroethane (DCE) to produce CVM. In direct chlorination, DCE is generated by the reaction of chlorine with the catalyst, while in the oxychlorination method, it is generated by the reaction of hydrogen chloride and ethylene in the presence of the catalyst and air (O2).

Production of butadiene rubber

Butadiene is a synthetic rubber widely produced and used due to its high abrasion resistance. It is mixed with other rubbers, processed with roller mills or extruders, and vulcanized into elastic rubber. It is then used for the production of tires, belts, shoes and tubes. In North America, Europe and Japan, butadiene is obtained as a by-product by catalytic cracking of ethylene or other olefins.

Applications :

• Car tire production
• Shoes
• Belts
• Fire hoses
• Toys
• Moulded rubber articles
• Sponge and foam products
• Waterproof materials
• Belt
• Adhesives

Ammonia production: Haber-Bosch process

Ammonia is the most widely produced chemical compound in the world. About 80% of ammonia is used in the production of agricultural fertilizers. The remaining 20% ​​is used for the production of synthetic fibers (nylon, rayon). Ammonia is produced by the Haber-Bosch process: atmospheric nitrogen reacts with hydrogen to form ammonia.

Hydrogen can be produced in several ways, but it is usually obtained by cracking natural gas (methane) or petroleum naphtha. Hydrogen is also recovered from recycled plastic (chemical recycling).