The project and production & service activities of the ENERGAS Group are focused on the search and implementation of design and engineering solutions for the creation of multifunctional gas treatment units.



Such units are designed for guaranteed long-term and continuous providing of high-quality gas treatment of various types and initial condition – in all gas-using industries.

Year after year, the ENERGAS team successfully implements various industry projects and receives new confirmations that gas treatment (Midstream) is always a carefully coordinated engineering calculation of an comprehensive process procedure that allows achieving and sustainably maintaining the specified gas parameters in terms of purity, humidity, temperature, pressure, flow rate and other regulations.

According to their type, ENERGAS gas treatment units come under groups of complete and multi-packaged.

Compact complete units consist of 1-2 modules, within which the equipment is integrated on a single frame. These are:

- Associated gas treatment units;
- Block-type gas treatment units (for natural gas);
- Fuel and starting gas treatment systems;
- Automated gas distribution stations.



Multi-packaged units are used in complex and large-scale projects. They are characterized by high capacity (flow rate of treated gas) and consist of several individual block-boxes with equipment for various purposes, which, when mounted, are docked together in a single building with a common roof. At the same time, a number of elements may have external version.

Such units operate on large generating facilities with large-capacity gas turbines, as well as at oil and gas production sites, where it is necessary to provide in parallel and continuously high-quality gas (with different parameters) for several main and auxiliary facilities.

In general, complete and multi-packaged ENERGAS units automatically provide purification, drying, heating, reducing, technological or commercial metering, quality control of gas before it is supplied to various gas-using equipment:

- Gas turbines;
- Gas-reciprocating units;
- Boiler houses;
- Gas-pumping units etc.

Revealing the importance and prospects of multifunctional units (MFU), the ENERGAS Group experts confirm their capabilities in the experience of developing and implementing specific projects.



ENERGAS - SPECIALIZATION EXPERIENCE

The companies of ENERGAS Group have agreed goals, tasks, professional specialization in the field of gas treatment and mutual responsibility for the quality of their work. Since 2007, 150 projects have been implemented. 290 compressor and multifunctional units were supplied for them.

In the oil and gas industry, ENERGAS equipment at 46 fields treats different types of gas: associated petroleum, natural gas, condensate de-ethanization gas, gas from Cenomanian water. Here the units operate at 63 sites.

These are: auxiliaries power supply complexes and power plants; oil treatment plants; oil processing and pumping shops; oil verification departments; booster pump stations; main transfer pumping stations; preliminary water removal units; central production facilities; oil and gas gathering facilities; terminal separation units; condensate de-ethanization units; condensate stabilization units; acceptance points; transportation systems of liquid hydrocarbons; complex gas and condensate treatment plants.



In electric power industry, ENERGAS equipment provides high-quality fuel gas for the 186 generating units, operating in a simple, cogeneration, combined or trigeneration cycle. The total electric capacity of the conjugated power units is more than 6,200 MW.

Gas treatment units operate with generating equipment of leading domestic and world manufacturers: UEC-Gas Turbines and UEC-Saturn, UEC-Perm Motors and UEC-Aviadvigatel, Kazan and Ufa Motor-Building Production Associations, Nevsky Zavod, Russian Gas Turbines, Power Machines, Alstom, Turbomach, Centrax, Solar, Pratt & Whitney, Rolls-Royce, Kawasaki, Wartsila, Cummins, Siemens, General Electric.

Special (individual) designing is embodied in multifunctional units at the engineering and production site of ENERGAS according to the ISO 9001 standards, in accordance with the rules and standards established in Russia. The equipment is designed and manufactured taking into account the scope of application, operating conditions, gas composition, the type and characteristics of the associated units, the specific project requirements of customers.

BASIC CONFIGURATION OF MULTIFUNCTIONAL UNITS

The minimum (basic) functionality of ENERGAS process units is gas filtration and metering. Such equipment includes five main elements.

Filtration system

As standard, the system includes two filtration lines with a throughput of 100% flow, or three lines with a throughput of 50% of the flow each. In special projects, a dual system is used, which consists of a pre-filtering module and a gas fine purification module.

Gas filters are selected depending on the composition of gas supplied to the facility, as well as the content of mechanical impurities and liquid fractions. Predominantly, two-stage coalescing filters with replaceable elements (cartridges) are used in ENERGAS equipment. Such filters provide a high degree of removal of droplet moisture and solid particles at the designed pressure drop. Also this method allows you to change the type of cartridges or a combination thereof to optimize the purification efficiency when the composition and characteristics of the incoming gas change.



In the case of high gas humidity there are used filters with a vortex lattice at the first stage of filtration and subsequent final purification by filter elements. The passage of the gas flow through the vortex lattice of the first stage of the filter creates vortices, causes flow interruption and a consequent reduction and increase of gas pressure. Due to this condensation of liquid impurities of gas takes place. High efficiency of gas purification is achieved by using own gas condensate as an absorbent.

In multifunctional units, the degree of purification reaches 100% for solid particles of at least 3 microns and droplet liquid of at least 5 microns. For particles ranging in size from 0.5 to 3 microns, the efficiency is 98…99 %.

Filters are equipped with sensors and indicators for monitoring pressure, differential pressure, gas condensate level, and blow-off & discharge pipelines with safety valves. For quick access to filter elements there is an add-on with a maintenance platform and hoists for removing the upper end covers of the filters.

Condensate drainage module

The gathering of gas condensate and mechanical impurities occurs automatically. As a rule, the drainage tank is located underground. If climatic conditions permit, ground execution is used, and the tank is equipped with electric heating.

The level of condensate in the storage tank is set and maintained at a given value by the automated control system. The drainage module is equipped with a liquid level control device and equipment for removing purification products into a mobile cistern.



Gas-metering unit

After purification, gas enters the metering unit, which can have one or more normal flow measuring lines, a low flow line, and a bypass line (in the case of one measuring line or on customer's request). The relative error of the metering unit is no more than 1%.

Commercial or process gas metering is carried out by measuring the volume and volume flow of gas under operating conditions and automatically bringing the measured volume to standard conditions, depending on the pressure, temperature and gas compressibility factor.

Primarily there are used turbine and ultrasonic primary flow transmitters (flow meters). Rotary, vortex, diaphragm, Coriolis or thermoanemometric flow meters also used. The data from the converters come to the corrector-calculators (flowcomputers).

Metering system performs the following functions:

- The registration of the volume values measured by the flow meters for each measuring line;
- Measurement of temperature and absolute gas pressure for each measuring line;
- Computation of gas compressibility factor;
- Computation of the correction factor and gas volume under standard conditions;
- Computation of the volumetric flow rate of gas under operating and standard conditions;
- Indication of measured and calculated physical values on each line on liquid crystal displays of gas volume correctors;
- Transfer of measured and calculated data from correctors to the control system of the gas treatment unit and, if necessary, to other monitoring systems;
- Processing of alarms and their retransmission to the control system of the gas treatment unit and, if necessary, to other monitoring systems;
- Maintenance of the archive database of measured values of gas volume and event log.

The commercial gas-metering unit allows to carry out mutual financial calculations between the supplier, the gas distribution company and the consumer, to control gas flow rate and hydraulic modes of gas supply systems, to make up balances of gas reception and supply, to control fuel use efficiency.



Automated control system

Multifunctional gas treatment unit is fully automated and do not require additional manual adjustment for debugging the correct interaction of various equipment systems.

Control system (ACS) performs launch (and preparing for start), shutdown, and maintaining the optimal operation mode; controls the process parameters; provides automatic protection and alarm; handles the parameters of the workflow and emergency events with the issuance of information via a standard exchange protocol.

The ACS is based on modern microprocessor technology, using advanced software and switching equipment. It is placed inside the block-module of complete unit (or inside the block-building of multipackaged unit) – in a compartment separated from the process part by gas-tight fire-resistant partition.

The main components of the ACS have redundancy, so that the failure of any of them does not lead to the shutdown of the gas treatment equipment. In the switching off of external electricity feeding, its own uninterruptible power supplies ensure autonomous operation of the software and hardware complex of the ACS for at least 1 hour.

The local control system is integrated with the upper level of the APCS. It provides remote control of unit, indoor gas hazard monitoring, output of information on the status of elements and components to the operator panel. Control of gas treatment equipment from the central panel of the facility is carried out in full, similar to the control "in site".



Life support and safety systems

In addition to the life support systems (lighting, heating, ventilation), the ENERGAS units are necessarily equipped with safety systems: fire and gas detection, alarms, fire fighting.

At treatment of low-pressure associated gas (with a pressure close to vacuum), an oxygen detection system is also installed - with a special sensor monitoring the oxygen content the gas stream.

ADDITIONAL FEATURES

In practice, the use of units only in the basic configuration is rare. As a rule, to solve project problems, additional assemblies and systems are embedded in the process flow diagram.

Systems of separation and dehydration

At the treatment of associated petroleum gas, in the equipment structure there is often included separator-slugcatcher which performs intake of peak liquid blowout and the smoothing of pulsations of gas mixture.

Also, gas dehydration unit based on adsorbers can be installed. This is necessary in the event that the capabilities of the basic filtration system are not sufficient to achieve the design set gas parameters by humidity.



Gas reducing system

If the gas pressure in the supply pipeline is higher than the level required for the correct operation of the conjugated gas-using units, the gas treatment equipment is equipped with a reducing subassembly, which includes one or two lines with redundancy.

The ENERGAS multi-packaged unit includes multi-line reducing system. This is necessary for the parallel supply of gas (with different pressure parameters) to once several facilities at one production site. The number of reducing lines depends on the number of facilities-consumers.

Gas heating unit

To achieve design gas temperature, the unit is equipped with a heating unit based on electric heaters or heaters with an intermediate heat carrier. The package includes a device for smooth adjustment and blocking heating.

As a rule, liquid heaters are shell-and-tube heat exchangers of various types, and network water is used as a heat carrier.



In the absence of an external heat source, MFU ENERGAS is equipped with its own modular boiler rooms.

Odorizing unit

The odorizing unit with a tank for odorant storage (a substance that gives a warning odor to gas) is an indispensable element of the process facilities used in the automated process of gas offtake and its treatment for transportation to the end consumer.

Gas quality control module

According to the special project requirements of the customer, the equipment for measuring and analyzing various gas parameters is built into the process flow diagram of the unit.

For example, a continuous gas chromatograph (calorimeter) with a sampling device. Its functionality is determination of the component composition of gas, measurement of calorific value, calculation of the density and relative density, calculation of the Wobbe index.

The measurement of the gas dew point temperature for water and hydrocarbons is provided by a moisture analyzer with a sampling device.

To control the purity of treated gas, an impurity content analyzer can be installed at the exhaust manifold.

Block-modular boiler room

The block-modular boiler room provides intermediate heat carrier for the gas-heating unit. Compact BMBR is placed in a special compartment inside the unit. The number of water-heating boilers and their useful thermal capacity are set depending on the volume of gas being treated.

BMBR is equipped with its own devices for reducing and measuring gas flow rate, safety systems, as well as an underground tank for draining heat carrier.

The workflow is automated; the local BMBR’s control system is integrated with the ACS of the unit.



EXAMPLES OF MULTIFUNCTIONAL UNITS INTRODUCTION

We present examples of the use of multifunctional units in the treatment of natural and associated petroleum gas for gas-using equipment of various types and purposes.

A brief description of some of the projects carried out by the ENERGAS Group in the oil and gas industry and power industry gives a certain idea of the process features and production capabilities of the gas treatment equipment.

Multi-packaged fuel gas treatment facility for the facilities of CGCTP at East-Urengoy licensed area

Complex gas and condensate treatment plant at East-Urengoy licensed area of JSC Rospan International (Rosneft) is equipped with the ENERGAS multi-packaged fuel gas treatment facility (FGTF).

The FGTF includes 8 units for various purposes, combined into two modules - the main (FGTM-1) and standby (FGTM-2). This unit performs gas filtering, metering, heating, reduction and in parallel mode feed it (with different parameters in terms of pressure, temperature and flow rate) to the facilities of main and auxiliary purposes.

Among them: gas turbine power plant, boiler house, technical propane-butane purification unit from methanol, intake flow lines, low-temperature separation unit, methanol regeneration unit, flare unit, booster compressor station of low-pressure gases, and condensate stabilization unit.

The maximum capacity of FGTM-1 for gas is 90,400 Nm3 / h. The rated gas flow of FGTM-2 is 32,612 Nm3 / h.



Automated gas distribution station AGDS Aleksandrovka

AGDS Aleksandrovka has been operating since January of this year and carries out gas offtake from the main gas pipeline, purification, commercial metering, quality control, pressure reduction, heating and gas odorization before its transportation to a remote thermal power plant.

AGDS equipment: 2 filtration lines with coalescing filters; condensate drainage unit (with a tank of 3 m3); 2 measuring lines with ultrasonic flow meters; 2 shell-and-tube heat exchangers; 2 lines of reduction; calorimeter; moisture analyzer; odorization unit (with a tank of 2.1 m3 for odorant storage); automated control system; life support and safety systems; standby generator.

Preparation of the intermediate heat carrier for the gas-heating unit is provided by the block-modular boiler room, the enclosure of which is docked to the main AGDS module. The BMBR includes two water-heating boilers with a total useful thermal capacity of 1 MW.



Associated gas treatment unit for gas-turbine power supply complex at Usinsk field

At Usinsk oil field (LUKOIL-Komi) there is operates power supply complex with an installed electric capacity of 100 MW and thermal capacity of 152.1 Gcal / h. The generating equipment includes five GTPP-25PA power units produced by JSC UEC-Aviadvigatel.

The main and reserve fuel for the power supply complex is associated petroleum gas. Its treatment and feed to the turbines of GTU-CHPP are carried out by the ENERGAS multifunctional gas treatment system, which comprises three compressor units and an associated gas treatment unit (AGTU).

The AGTU performs flow measurement and gas filtration, it is equipped with a two-line unit of commercial metering, a separator-slugcatcher and a filtration system. The degree of gas purification is 100% for the liquid fraction and 99.8% for solid particles larger than 10 μm.

Additional functionality is fuel treatment for a boiler house for field's own needs. For this, the AGTU is equipped with a gas heating unit and a reduction system. Capacity of AGTU is 24,059 m3 / h.



Block-type gas purification unit for GTU-TPP in Yelabuga

At the end of 2018, in the city of Yelabuga (Republic of Tatarstan), GTU-TPP with electrical capacity of about 20 MW and thermal capacity of 28 Gcal / h was put into operation. The main equipment consists of 4 Solar gas turbines of the Taurus 60 GS type and 4 waste-heat boilers. Turbines fuel is natural gas.

As part of the power plant there is operates ENERGAS gas treatment system, which, in addition to the booster compressor station, includes a block-type gas purification unit. BGPU is a typical example of a compact unit in the basic configuration. All process equipment is integrated on a single frame. The complete unit has a small capacity (8,240 m3 / h), due to the low power of conjugated gas turbines.

In accordance with the project, BGPU provides gas purification from solid particles and droplet moisture to the turbine manufacturer's design requirements, gathering of trapped liquid into a drainage tank with subsequent transfer to a mobile vessel or special transport, gas flow measurement, determination and recording of gas composition and its changes, determination of calorific value, gas dew point measurement.



Fuel and starting gas treatment system for gas-pumping units at Alan field

A booster compressor station for natural gas transportation consisting of two GPA-16 Volga gas-pumping units (KMPO) operates at the Alan field in Uzbekistan (NHK Uzbekneftegas). BCS is equipped with the ENERGAS fuel and starting gas treatment system.

The FSGTS of GS-FHP-400/56 type is a multifunctional unit for purification, heating and reducing gas. It consists of coalescing filters-separators (gas filtration degree - 99.98%), automatic condensate drainage system, electric heaters, two-line reduction units for starting and fuel gas.

The gas treatment system is placed on an open frame. Assigned resource (service life) of FSGTS is 25 years. The project was implemented in the shortest possible time; designing, production, factory testing and delivery were completed in 2 months.



Multi-packaged gas treatment unit for the combined-cycle power units of Pregolskaya TPP

On March 2019, the launch of Pregolskaya thermal power plant with capacity of 455.2 MW was held. This is the largest facility of the new Kaliningrad generation. The TPP consists of four combined-cycle power units, each of which includes 6F.03 gas turbine (produced by the Russian Gas Turbines LLC), generator (SPA Elsib), steam turbine (Power Machines PJSC), waste-heat boiler (Machine-Building Factory of Podolsk JSC).

Fuel supply for TPP’s power generating units is provided by comprehensive gas treatment system of ENERGAS: gas treatment unit (GTU), booster compressor station, and control module.

Multi-packaged GTU with a capacity of 106,000 Nm3 / h was manufactured by ENERGAS under a special project. This is a process unit consisting of several block-boxes with equipment for various purposes, which are joined in a single building during mounting. The exceptions are the inlet filtration module and the condensate drainage subassembly (with a 10 m3 drainage tank), which have outdoor design on an open frame.

In addition to the external elements, the GTU is equipped with a fine gas purification system, a commercial gas-metering unit (with ultrasonic flow meters), a gas heating subassembly, a reducing system, and a gas quality control module.



Associated gas treatment facility for the gas-reciprocating power supply complex at Barsukovskoye field

Barsukovskoye field (RN-Purneftegaz LLC, Rosneft), located in the Yamal-Nenets Autonomous Area, is equipped with autonomous power supply complex consisting of 10 Cummins gas-reciprocating units with a capacity of 1.5 MW each. The power plant built by LLC Alliance Generation supplies electricity to infrastructure and process sites of the field.

The fuel is associated petroleum gas. Its design parameters (in terms of purity, temperature, pressure and flow) are provided by ENERGAS fuel gas treatment facility (FGTF). This is a multifunctional complex, which comprises: gas filtration system with two-stage coalescent filters (purification rate is 100% for the liquid fraction and 99.9% for solid particles larger than 2 microns); condensate drainage module with underground tank; commercial gas-metering subassembly with ultrasonic flow meters; gas heating module based on a shell-and-tube heat exchanger; two-line reducing system; block-modular boiler room for the treatment of the heat carrier, including two boilers with a total thermal capacity of 0.19 MW.

FGTF was commissioned in June this year. The rated capacity of the facility is 5,000 m3 / h. Coefficient of operational reliability is 0.99. Assigned resource (lifetime) is 30 years.



In conclusion, we note that the ENERGAS Group, thanks to the development of partnerships and cooperation ties in its segment of process equipment, is building up its own unique engineering experience and continues to reveal the possibilities of multifunctional units for their targeted implementation in gas treatment projects of varying complexity and scale.

Industry-specific magazine "SPHERE. Oil & Gas"

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