Introduction of Anhydrous Ammonia Sphere:-
Anhydrous Ammonia Spherical Tanks
Uses and Properties of Ammonia:
Ammonia is a colorless, toxic gas with a strong irritating odor. It is manufactured in large quantities for industrial purposes and is used in the production of nitric acid, fertilizers, and explosives etc.
We are exporters and manufacturer of Ammonia Sphere, Ammonia Storage Sphere, Ammonia Spherical Tank, Ammonia Horton spheres, Diameter ranging from 10000 mm to 22000 mm & thickness upto 72mm, as well as Refrigerated spheres for Butadiene & Ammonia storage.
The spheres are designed as per ASME Sec. VIII Div.1, ASME Sec. VIII Div.2. Codap 2000, AS 1210 and BS 5500 codes. We have executed storage facility including Mechanical, Civil, Piping, Instrumentation and Electrical.
Technical Specification of Ammonia Horton sphere:
Design Pressure: 12 Bar to 28 bar
Design Code: PD 5500, CODAP 2000, ASME SECTION VIII DIV 1 & 2, AD MERKBLATTER AND OTHERS.
Design Temperature: - 46 Deg C to + 70 Deg C
Volume: 200m3 to 12000m3 for each sphere
We use various international design codes for designing of Ammonia Sphere as follows:
PD 5500: Specification for unfired Fusion welded pressure vessels
EEMUA: Guide for design, construction and use mounded horizontal cylindrical vessels for pressurized storage of AMMONIA at ambient temperatures
EEMUA 190: Selection criteria AMMONIA storage systems
ASME sec. VIII Div. 1 and 2
Storage of Ammonia Spherical Tank:
1. Mainly used for storing many kinds of liquefied gas and chemical liquid
2. Volume varies from 200 to 12,000m3.
3. Material varies from high alloy steel to stainless steel.
4. The manufacture of spherical tanks includes making spherical shells, field installation, field welding and a series of tests
Advantages of Ammonia sphere:
Less Land Area,
Uniform Stress Distribution,
Large Storage Volume,
High Quality And Low Cost
Spherical tanks are used for different storage like:
Ammonium Nitrate Storage
VCM (Vinyl chloride Monomer) Storage
We also Manufacturer of Different types of Ammonia tank.
Ammonia Storage tank
Anhydrous ammonia from production plants is either used directly in downstream plants or
Transferred to storage tanks. From these the ammonia can be transferred to road tankers, rail
tank cars or ships.
Emissions during normal operation are negligible. Major leaks of ammonia from storage tanks are almost unknown with most of the leaks which do occur being during transport or transfer. A well designed, constructed, operated and maintained installation has a very low probability of an ammonia leak of hazardous proportions.
Ammonia is usually stored by using one or other of three methods:-
Fully refrigerated storage in large tanks
Pressurised storage spheres
Ammonia Spherical Pressure Vessel:
This type of vessel is preferred for storage of high pressure fluids. A sphere is a very strong structure. The even distribution of stresses on the sphere's surfaces, both internally and externally, generally means that there are no weak points. Spheres however, are much more costly to manufacture than cylindrical vessels.
Storage Spheres need ancillary equipment similar to tank storage - e.g. Access manholes, Pressure / Vacuum vent that is set to prevent venting loss from boiling and breathing loss from daily temperature or barometric pressure changes, Access ladders, Earthing points, etc.
An advantage of spherical storage vessels is, that they have a smaller surface area per unit volume than any other shape of vessel. This means, that the quantity of heat transferred from warmer surroundings to the liquid in the sphere, will be less than that for cylindrical or rectangular storage vessels.
SAFETY IN STORAGE & HANDLING OF AMMONIA
Ammonia is the single largest hazardous chemical manufactured, stored and transported worldwide. Ammonia is manufactured at elevated temperature and pressure in presence of promoted Iron catalyst.
Types of Tanks:
Small volumes of ammonia are stored in cylindrical horizontal bullets or spheres designed for ambient temperature and with no refrigeration. This is definitely the safest system, but it cannot store large volumes at reasonable cost.
We BNH Gas Tanks undertake the Project Execution on LSTK / EPCC (Engineering, Procurement, and Construction & Commissioning) basis.
The scope of EPCC Contracts includes:
• Design and Detailed Engineering
• Fabrication, Testing, Procurement, Erection of Spherical tanks and piping
• Safety measures like Fire Fighting etc.
• Supply and Installation of entire sphere
• Ground Improvement & Civil works
• Electrical and Instrumentation work
We manufacture Ammonia spherical tanks. We have in-house design department, which is capable of designing Spheres with international codes such as ASME, PD 5500, DIN. The volume range from 200 m3 to 12000 M3. The Spheres are provided with all accessories like safety fittings, valves, pipelines, Excess flow valves, internal valves as per requirement. The above photographs shown manufacturing of Ammonia sphere consisting of various activities like Pressing of plates at shop , Pre fabrication of Equator , Polar and crown plates , Legs or columns for sphere, Radiography welding, NDT testing, Erection at site, Hydrotesting and coating of Ammonia spheres.
Total Project Commissioning for BULLET:
• 5 x 3100 cum. Ammonia Sphere
• 4 x 1500 cum. Ammonia Spherical tank
• 4 x 6000 m3 Ammonia ball tank
• 4 x 4200 cum. Anhydrous Ammonia Sphere
• 2 x 2000 cum. Ammonia Horton sphere.
• 4 x 8200 cum. Ammonia Spheres
Material of construction: SA 537 CL 1, SA 516 GR 70, BS 1501-1 225 490 A, EN 10028-3 P355NL2 AND OTHERS
Safety Design Features
• Remote operated fire-safe emergency shut off valves
• Redundancy of level instruments
• Manhole at top of sphere.
• Insulation / fireproofing of sphere & supports.
• Paving and sloping of diking / impounding / ground underneath
• Leak detection, deluge and sprinkler system.
Advantages / Comparison of Ammonia Sphere and Ammonia Mounded Bullets
IS MOUNDED BULLET FOR STORING Ammonia IS BETTER THAN USING SPHERE? AND WHY?
The choice between a bullet and a sphere is a matter of economics and project logistics. So one is better than the other only in the matter of which has a cheaper overall installed cost.
The sphere of course uses less material than a bullet for the same amount of liquid storage but is somewhat more difficult to fabricate. The diameter for shipping of a storage tank is in the order of 10 to 14 feet depending on the method of transport. This would limit a sphere's storage capacity if it is shop fabricated. For a 10 foot diameter tank, you can get 10 or more times the storage in a bullet than a sphere. For this reason, you usually only see spheres used for very large volumes (maybe in the order of 300,000 gallons or more) because they must be field fabricated to compete with the bullet in cost.
For smaller storage tanks, the bullets are preferred because they can be shop fabricated and more easily transported.
COMPARISION OF AMMONIA SPHERES WITH AMMONIA STORAGE TANKS:
1) Least initial investment and financial risk in case of Ammonia multiple storage tanks as compared to sphere of similar or larger volume.
2) Ammonia sphere of same volume needs more time for construction as compared to Ammonia multiple storage tanks.
3) Ammonia multiple storage tanks makes the project faster, economical, easier and will in turn help the company to start the terminal as soon as possible which in turn will generate good immediate returns.
4) Ammonia Storage tanks are much safer since it weight is distributed evenly on a larger area thus reducing chances of collapse as compared to sphere, especially in small islands prone to earth quakes, cyclones and Tsunami as can be verified from the recent incident in Japan where a row of Ammonia sphere went under severe fire condition.
5) Multiple Ammonia storage tanks have an added advantage that the load is distributed over a larger area thus the problem of uneven settlement / collapse is largely reduced.
6) In case of installations with Multiple Ammonia storage tanks if there is any problem / maintenance / repair / breakdown of any one tank the outlet and inlet valves of the same can be closed and the tank can be isolated, also in case of emergency the Ammonia product in the tank under repair / maintenance can be easily transferred to another tank located in the same plant thus increasing safety of the plant. Whereas in case of sphere if there is any problem with the sphere or its valves or pipeline the entire plant comes to a stand still (This is a loss to the company in terms of business loss, product loss, as well as extra demurrage that the company may have to pay to the shipping company if unfortunately the Ammonia ship also arrives the same time when the sphere has generated a possible breakdown). But in case of multiple storage tanks even if one of the tank generate a possible breakdown and the Ammonia ship also arrives the same time still the Ammonia from the ship can be unloaded to the remaining tanks and the company will have to incur least loss due to ship demurrage.
7) Though there is a common notion that for the same volume a sphere has the least surface area and least thickness and hence lesser weight and less cost but our past experience suggests that weight saved in making a sphere as compared to storage tank is lost as wastage in the development of various sections (petals and crown) thus leaving little or no benefit of the weight saved.
8) The fabrication cost increases considerably in case of sphere as compared to multiple Ammonia storage tanks , since the sections have to be pre fabricated at shop, shipped to site, adjusted, assembled and welded at site piece by piece in proper sequence, heat treated, radiographed and tested at site. Fabrication of sphere requires lot of time since the petals / sections are required to be assembled piece by piece in proper sequence and completion of one stage is entirely dependent on completion of the earlier stage as so on and so forth. More over there is a continuous requirement of close monitoring, blockage of all construction equipments and manpower till the entire completion of work sequence by sequence, this makes the fabrication of sphere still more costlier and time consuming as regards to blockage of manpower, machinery rent etc.
9) Sphere once fabricated cannot be moved or relocated from one place to another and if in case any relocation (due to sale of plant or plant relocation) is required the sphere has to be cut into several small pieces and transported to site and then reassembled and re-fabricated at new site this is as good as manufacturing a brand new sphere at site and hence the after sale value of a sphere is much less and as compared to Ammonia storage tanks which can be sold out for good returns.
Why is Ammonia stored in spherical tanks?
A sphere is a very strong structure. The even distribution of stresses on the sphere's surfaces, both internally and externally, generally means that there are no weak points. That's why a drop of water forms a spherical shape when under free fall, in short; it achieves a shape where all the resultant stresses neutralize when no external force (gravity) is acting on it. Moreover, they have a smaller surface area per unit volume than any other shape of vessel. This means, that the quantity of heat transferred from warmer surroundings to the liquid in the sphere, will be less than that for cylindrical or rectangular storage vessels. Thus less pressurization due to external heat.