1(9) JORDBERGA PROJECT BIOMETHANE FROM BIOGAS PLANT TO TRANSMISSION NET BIOGAS COMPRESSOR PACKAGE Göteborg Lars-Gunnar Börjesson COWI AB Skärgårdsgatan 1, Göteborg Postadress: Box 12076, 402 41 GÖTEBORG Telefon: 010-850 10 00 Telefax: 010-850 11 44 Dokumentnr:
2(9) TABLE OF CONTENTS Page 1 INTRODUCTION 3 2 SITE LOCATION AND ENVIRONMENTAL CONDITIONS 3 2.1 Site Location 3 2.2 Weather Conditions 3 3 CODES AND STANDARDS 3 3.1 General 3 3.2 Specifications 4 3.3 Standards 4 3.3.1 International 4 3.3.2 National 4 4 DESIGN CONDITIONS 4 4.1 Process Conditions 4 4.2 Operation and Design Conditions 6 4.3 Utilities 6 4.4 Area Classification 7 5 SCOPE OF SUPPLY 7 5.1 Design Responsibility 9 APENDIX A Specification for electrical, instrumentation and control
3(9) dat. / Date of rev. 1 INTRODUCTION The biogas project is located in Jordberga, Skåne in the south of Sweden where biogas will be produced from fermenting sugar beets, corn and other agriculture residues. The plant will be finalized in 2013 and will deliver the biogas to the natural gas net near Trelleborg end of 2013 or beginning of 2014. The gas will be purified and connected to the low pressure natural gas net. The compressor unit described in this technical specification shall compress the gas and deliver it to the high pressure gas net during periods when the consumption from the low pressure net is low. 2 SITE LOCATION AND ENVIRONMENTAL CONDITIONS 2.1 Site Location 1. The compressor unit will be located at Swedegas MR-station (Measure and Regulation station) at Trelleborg gas transmission trunk line in the south of Sweden. 2.2 Weather Conditions The compressor unit shall be installed in a weather protected building/container but must withstand outside temperatures of -25 C. Temperatures: Max: Min: approximately +35 C (vendor to advice) approximately +5 C 3 CODES AND STANDARDS 3.1 General The compressor unit shall be designed to comply with applicable Swedish laws, standards and directives, valid at the time of contractual agreement. Even such laws, standards and directives that are under processing and considered to be well known within the line of business, but not valid at the time of contractual agreement, shall be taken into consideration. The vendor is responsible for the CE-marking and ATEX approval of the compressor unit.
4(9) dat. / Date of rev. 3.2 Specifications In case of conflict between this specification and its appendices or codes and standards, the order of precedence shall be as follows: 1. Local codes and statutory requirements 2. The text of this specification 3.3 Standards The compressor unit shall comply with applicable parts of codes and standards below. 3.3.1 International The Vendor shall in all cases follow the imperative international standards as required to deliver a CE-marked compressor unit. PED 97/23/EC ATEX 94/9/EC 98/37/EEG - Machine Directive Low Voltage Directive LVD 2006/95/EC 3.3.2 National The compressor unit will be installed and operated in Sweden. The Vendor shall design the compressor unit and building in accordance with applicable Swedish laws, standards and directives AFS - Swedish legislation concerning worker's protections ELSÄK:FS 2008:1 - Swedish electrical regulations SS 436 40 00 - Rules for design and erection of electrical installations NGSA 2011 Boverket BKR and BBR 4 DESIGN CONDITIONS 4.1 Process Conditions The compressor unit will be connected to the Biogas Project which will produce biogas from sugar beets, corn and other agricultural residues. The gas will be delivered cleaned and dried. During the winter half of the years the gas will be consumed from the low pressure gas net and when consumption of gas in the low pressure net goes down the gas will be fed into the high pressure net. Delivery of the gas to the compressor will be from the low pressure natural gas
5(9) dat. / Date of rev. distribution net. There will be a 16.5 km long pipeline from the biogas production unit to the compressor unit. The specification for the biogas is indicated in the table below: Biogas Comp. CH 4 vol-% 96,3-98,3 C 2 H 6 vol-% - C 3 H 8 vol-% 1) Other HC ppm < 10 H 2 O ppm 850-1150 N 2 vol-% 1,2-1,4 CO 2 vol-% < 2.5 O 2 vol-% < 0.1 H 2 ppm < 1000 H 2 S mg/ Nm 3 /h < 5 NH 3 ppm < 10 S mg/ Nm 3 /h < 10 1) Gas composition above is without propane injection and taken from a similar plant built by the same vendor. Propane injection can over time vary between 2 to 8.3 vol. % of total biogas flow 2) The compressor must also be suitable for gas with composition acc. to SS EN 155438 and the gas composition shown at www.swedegas.se (monthly average values) 3) Dew point for water -8 deg. C at 70 bar 4) Dew point for HC -2 deg. C up to 70 bar Max.load Min.load Flow Nm 3 /h 1300 200 The operation of the compressor unit will be mainly during May to October each year. Maximum capacity is expected to be reached in July-August. The maximum capacity shall be related to normal suction pressure and a discharge pressure of 65 barg. The compressor shall operate between the following suction pressures: Suction side Normal Start Min Press. bar g 6.5-7 10 4,0
6(9) dat. / Date of rev. The compressor unit should start at 10 barg suction pressure (should be possible to adjust downwards) and when the minimum suction pressure 4 barg is reached the compressor unit shall stop. Suction temperature is between 0-20 C The discharge pressures for the compressor unit will be within the following range: Disch. side Normal Max Min Press. bar g 55-65 80 50 If the gas feed from Denmark for some reasons fail a security of supply situation could occur. The discharge pressure of the compressor unit could then be as low as 20 barg but shall still be possible to operate. The discharge temperature after last stage must not be higher than 50 C so if an aftercooler is needed this must be included. 4.2 Operation and Design Conditions The compressor unit shall be suitable for automatic start and stop with no operators present. The manufacturer shall indicate the time needed from start signal to full load. The compressor unit could consist of either 2 compressors with each 75% capacity or 3 compressors with each 50% capacity. Most cost effective solution to be chosen. Compressors to be based on API618 but with deviations mentioned in the offer. Guarantee period shall be 36 months from delivery and 24 months from commissioning. Guaranteed operating time per year (included wear parts such as piston rings, packing rings and valves) shall be 4500 hrs continuous operation with one maintenance period per year. Estimated operation time is mainly between May to October and reaching maximum capacity during July-August. The compressor shall be a non-lube compressor. No oil contamination into the discharge side is allowed. The vendor shall specify the compressor maintenance schedule meaning stop cycles and required down times. The compressor unit shall be equipped with pulsation dampeners on suction and discharge side. The resulting maximum pulsation level on the discharge side of 2 % peak-to-peak is allowed. For the suction side this value shall be maximum 0.5 %. 4.3 Utilities Leakage of process gas to atmosphere shall be zero. Except for electric power no utilities are available.
7(9) dat. / Date of rev. Cooling water: There is no cooling water system available within the site so cooling of cooling water to be with air coolers. Nitrogen: There is no nitrogen system available within the site. Instrument air: There is no instrument air available within the site. Flare system: No flare system will be installed 4.4 Area Classification The site area is classified according to the following: Zone 2 Explosion group IIA Temperature class T1 The equipment must fulfill requisite requirements for this hazardous area classification. 5 SCOPE OF SUPPLY The quotation shall include detailed design, manufacturing, quality control, tests and delivery of a compressor unit including: One complete compressor unit with skid mounted direct driven compressors with drives and necessary buildings/containers. The buildings/containers to be according to protection class EI60 with gastight connections between compressor rooms and location of MCC, frequency converters etc. Fire and gas alarm to be included. The buildings/containers to be heated to + 5 deg C and equipped with sound proofing to achieve 45 db(a) at 5 m from the unit. Foundation for compressor building/container to be offered as an option The compressors to be operated with capacity control between 200 and 1300 Nm³/h using compressors in sequence, frequency converter, suction valve unloaders and by-pass control if necessary. Vendor to choose the best solution regarding operability and energy consumption. The compressors shall not have any critical speeds in the chosen speed range. Pipe connections to be located at edge of skid. Frequency converters, switch gear and MCC in separate room Instrument air supply (if needed) Instrument and sensor lines in SS Necessary control and field instrumentation equipment Control system unit (PLC) for control and monitoring including interface for communication with existing DCS/PLC system at Swedegas and the biogas production unit Alarms and shutdowns in PLC for oil, cooling water and process gas
8(9) dat. / Date of rev. High vibration sensor with shutdown Local panel with pressures and temperatures for oil, cooling water and process gas Inlet strainer Painting acc. to manufacturers standard but suitable for outdoor location Compressor noise level shall be specified Witnessed Mechanical Test Run (FAT) including oil and cooling system SAT including capacity test Documentation in terms of - technical description - technical data sheet - process flow diagram and P&ID diagram - GA drawings - cause effect diagram - instrument list - assembly drawings and parts lists - quality plan, procedures and procedure qualifications - risk assessment acc. to PED - Installation, operation and maintenance manual - Stress calculations for pipes and vessels - 100 %x-ray on all pipe welds for biogas piping within the unit - welder qualification - material certificates acc. to EN 10204 3.1 for all pressure containing parts - design review certificate acc. to PED - hydraulic test records - inspection plan - final inspection certificate and FAT report - NDE reports - declaration of conformity and ATEX approval - general arrangement including required access area for maintenance - civil information with indication of compressor foundation and forces - consumer figures for the total unit - time schedule for design and manufacturing - process guarantees - description of services for commissioning and start-up Declaration of conformity and User s manual to be in Swedish language Recommended spare parts for two years of operation (as option price) One spare motor for compressor (as option price). Strategic spare parts (as option price) Wear parts (as option price) Installation supervision Commissioning and start up assistance and approval for start up
9(9) dat. / Date of rev. Temperature and pressure transmitters for oil, water and process gas (before and after each compressor stage). To be equipped with two oil pumps, either one crankshaft driven oil pump and one electrical driven auxiliary oil pump or two electrical oil pumps. Each pumps to have separate RV. Oil filters shall be double with reversing valve. Oil cooler to be equipped with self-acting control. Service agreement including yearly maintenance period (option price) One extra empty room for flow measurement ( approx.2.5 X 2.5 m) 5.1 Design Responsibility This specification states the main functions of the object and demands on the design. The Vendor shall manufacture the design in its entirety and bear the responsibility for the same. The Vendor shall obtain the necessary approvals from appropriate authorities. The purchaser normally makes specific demands on the design with regard to operation and maintenance; the design shall be submitted to the purchaser for approval before manufacturing.