Technical parameters of 25 tons gas fired steam boiler in refinery

 1- Scope of Work :

The project will cover the following : design, supply, erection and operating steam boiler , the project is ( on turn key job basis ) .

The project will be delivered to HRC in guaranteed conditions workings .

According to the following technical specifications :

- Outlet steam pressure : 38 kg/ cm² .

-Outlet steam temperature : 450±5 C° .

- Outlet steam quantity : 25 t/h at least .

- Number of the burners : two burners .

2-Mechanical Part.

2-1- Boiler Data :

- Outlet steam pressure : 38 kg/ cm² .

- Outlet steam temperature : 450±5 C° .

- Outlet steam quantity : 25 t/h at least .

Water and fuel specification provided by refinery :

-Boiler feed water temperature : ambient temperature ( 5-20 ) C° .

-Boiler feed water type : dimi water ( treated ) (water specifications attached) .

- Feed water pressure : systematic atmospheric pressure .

- Types of used fuels :

a- Fuel oil (specifications attached) with systematic atmospheric pressure and temperature ( 70-80 )° C to boiler borders.

b- Fuel gas (specifications attached) with pressure ( 3.5-4) kg/cm2.

2-2- Technical Requirements :

-The boiler shall be capable of producing steam at rated final pressure , temperature and steam flow when burning any of the specified fuels .

- Operational pressure and the temperature of steam should be constant at any boiler's capacity beginning from 60% .

- The efficiency should not be less than 91% of nominal load .

- The delivered burners must be in accordance with the up to date low NOx type and must be able to burn completely , cleanly and efficiently all the fuels specified above .

- A reduction pressure station of 38/14 bar with automatic control should be erected with its accessories .

- A special stack for the boiler should be erected independently and it should achieve the operational and environmental conditions.

- The contractor should install suitable valves on all pipes, that allow to insulate the boiler from all inlet and outlet pipes .

- The contractor should erect galvanized ladders , stairs ,platforms and walkways for complete access to all instruments and equipment easily .

- The boiler must be protected by a suitable shelter .

-All materials and equipment must be new and not renewed ,

- The bidder could pay a visit to H.R.C. in order to be fully aware of the site of erecting the boiler .

25 tons gas fired steam boiler

3- Electrical Part

Electrical Requirements :

1- All electric equipment of the boiler must be suitable for the EX. PROOF acc. to the type of the material which will be used to operate the boiler .

2- The submitted electric equipment of the boiler must be acc. to an international standard : ( NEC- IEC) or their equivalents.

3- Electric used system : 380 / 220 -50 Hz

3 ph +N+PE - 400 Volt - acceptable .

4- All drawings - Catalogs - single line diagram - must be submitted.

5- EX-PROOF - Certificate must be submitted for the motors and the relative equipment.

6- H.R.C will provide the necessary electric power for the boiler operation board .

4- Instrumentation Part

4-1- : Field Instrumentation

-include ( local indicators , switches , transmitters,…) for operating parameters ( Pressure , level , temperature , and flow ).

-All field instruments should be of modern types , protection degree IP67 , designed and installed in line with current EUROPEAN STANDARDS or their equivalents.

-Power supply of all field instruments is 24 VDC.

4-2- Automatic Control of Boiler

The offered control system should be pragramable logic control (PLC) which consists of the following loops at least :

Combustion control system .

Feed water control loop.

Steam temperature control loop .

Burner management system (BMS) .

- local control cabinet for every burner should be installed with protection degree IP55 at least .

- control System components should be of modern version for this kind of steam boilers control .

-Human Machine Interface (HMI) should be installed .

-Possibility for operating and shutdown from site OR HMI .

-HMI should have screen for monitoring in real time and archive. And display the alarm and protection states .

-PLC modules installed in suitable cabinet with racks and connect with HMI . the contractor should built a suitable room for plc cabinet. Allowing to easy work with cabinet.

-The contractor should install all parts for safety operating and shutdown according his design ( relays , lamps ,contactors , horn , …) even they aren't mentioned above .

4-5- The System Accessories :

1.Portable computer (Labtop) for loading the control software .

2.Colored laser printer to print the reports .

4-6- Cables :

-The bidder should provide cables(Armed, PVC isolation, Copper shield, High temperature resistance)

-To lay the cables inside metallic tunnels with tracks according to the boiler environments .

-25% as cables reserve .