GB2508657A - Vertical degasser - Google Patents

Abstract

A degasser for a chemical plant wherein the degasser has a vertical arrangement. The degasser is ideally used in a hydrogen production plant. The degasser may comprise a liquid inlet 15, dome 2, gas liquid separator distributor 3, support grid 4, gas or steam inlet 13, gas distributing pipe 11, vapour outlet 10 and BFW outlet 9. The degasser is ideally of slim design and allows for an arrangement of different tray intervals to enable different process requirements to be met. This design provides for more efficient operation of the degassing process and a smaller equipment footprint.

Description

VERTICAL DEGASSER FOR HYDROGEN OR OTHER CHEMICAL PLANT

FIELD OF THE INVENTION

(001) The invention relates to water degassers for use in hydrogen or other chemical p1 ants.

BACKGROUND OF THE INVENTION

(002) Chemical plants, such as hydrogen plants require the use of large amounts of water. The water used must be prepared in order to meet purity and quality requirements for the chemical processes. For example. gases, minerals and other impurities need to be removed from the water prior to its use.

(003) In addition, the water used may he treated in a degasser, which are generally configured in a horizontal arrangement such as those shown in US patents 2,296,543; 3,803,001; and 5,728,200 and in US published patent application 2002/0007736. A vertically arranged degasser vessel is shown in US patent 5,203,890, hut this degasser is not used for chemical plant operations. The known degassers usually comprise a separate body and arranged dome. The water to he treated in the degasser flows from the top to the bottom of the dega.sser with a counter flow of treatment vapor, such as steam or nitrogen along with suitable chemicals. The interior of the degasser holds treatment trays that are arranged at special intervals according to the treatment requirements.

(004) The horizontal arrangement of the degasser is not effective with regard to process flow and req uires a high volume and a large equipment footprint with significant structural support. For example, horizontal degassers are often contained within a supporting steel structure.

(005) There is a need in the art for improvements to degassers for use in chemical plants.

SUMMARY OF THE PRESENT INVENTION

(006) The invention provides a degasser for a chemical plant that has a vertical arrangement. This design provides for more efficient operation of the degassing process and a smaller equipment footprint.

DErAILED DESCRIPTION OP THE INVENTION

(007) The invention provides a degasser that is arranged in a vertical orientation as will be more fully described with reference to the drawing figures, wherein like components are numbered with like reference numerals.

(908) Figure. 1 shows a degasser system arranged in a vertical orientation that includes the following components: Ref # Component Ref it Component 1 Situp degasser 11 Start up pipe 2 Dome 12 Chemicals dosing inlet 3 Gas liquid separator distributor 13 LP steam inlet 4 Support grid 14 Horizontai guide Bed limiter 15 Process condensate or other medium to be degassed inlet O Slotted pipe inlet 16 Manhole access 7 Compensation line! BFW minimal 17 Hot insulation flow S Flange connection 18 Vortex breaker a 1 Vapor outlet B Section B with random aek1fl (009) The vertical degasser of the invention has a slim design, allows for arrangement of different tray intervals and also for quick changeability of tray positions to meet different process requirements. For example two different tray arrangements are shown in Figures 2 and 3. Figure 2 shows greater detail of thefl ome portion of the degasser with a first embodiment for an arrangement of trays therein, including the following components.

Ref -ft Component Ref # Component I Sump degasser 10 Vapor oudet 2 Dome 14 Horizontal guide 6 Slotted pipe inlet 15 Process condensate or other medium to he degassed inlet 7 Compensation line! BFW minimal 19 Process trays flow 8 Flange connection (010) Figure. 3 also shows greater detail of the dome portion of the degasser with a second embodiment for an arrangement of trays therein, including the following components Ref-it Component Ref # Component Sump degasser 10 Vapor outlet 2 Dome 14 Horizontal guide 6 Slotted pipe inlet 15 Process condensate or other mediwn to he degassed inlet :.

/ Compensalion line! BFW minima! 20 Process trays flow 8 Flange connection (OH) Also as shown in Figures 2 and 3 the process trays may he single or muitiflow trays. As mentioned the intervals between trays can be easily changed to meet process requirements. The total number of trays can also be easily changed with the usual number being in the range of four to eight trays. but more or less are possible within the vertical degasser of the invention.

(012) Details of the start up pipe ii are shown in Figures 4A and 4B wherein Figure 4B is a cross sectional view taken along line A--A of Figure 4A. The components shown in Figures 4A and 4B are as follows.

Ref # Component 11 Start up pipe 13 LP steam inlet 21 Outlet holes (013) The outlet holes can be arranged along a central row with additional external rows. The total number, diameter and arrangement of the holes can vary depending on the process requirements. En order to avoid vibration, hole pitch may he irregular with all of the holes being placed so that there are different hole to hole distances.

(014) Figure 5 is a detailed drawing of the slotted pipe inlet 6 showing the orientation thereof with respect to the dome center line 22.

(015) Figures 6.A and ÔB are detailed drawings of. the gas liquid separator distributor 3 showing process condensate inlet 15 and-splash plate 23, wherein Figure 613 is a cross sectional view taken along line AA of Figure 6A. The diameter of the splash plate 23 can be varied to meet process requirements and is fitted to the pipe.

(016) Figures 7A and. 7B are further detailed drawings of the gas liquid separator distributor 3 showing process condensate inlet 15, vapor outlet 10, bed limiter 5, splash plate 23, and cover 24 wherein Figure 7B is a cross sectional view taken along line A--A of Figure 7K Also shown in Figure 7A is a portion of section A. (017) Figures SA and SB are detailed drawings of the bed limiterS showing cutouts 25 to allow for support clamps to the distributor wherein Figure SB is a cross sectional view taken along line A--A of Figure BA. The bed limiterS is affixed to the distributor but may be removable. The minimum free area of the bed limiter should exceed 75% of the column cross sectional area. The bed limiter is designed to he suItable for horizontal transport.

(018) Figures 9A and 9B are detailed drawings of the distributor and bed limiter 5 showing gas risers 26, holes 27 and support clamps 28 wherein Figure 9B is a cross sectional view taken along line AA of Figure 9A, The gas risers 26 may be sized to have a diameter sutabie for the process requirements. in addition the number of holes 27 is set at the suitable number for the process requirements. The support clamps 28 connect the distributor to the column and can be of an appropriate number for the load required. The support clamps can include a horizontal and vertical slot to allow for clamping of the distributor in either configuration. The bed limiter S is fixed to the distributor, The distributor has a diameter arid inclination necessary for the process requirements.

(019) Figures WA and LOB are detailed drawings of the support grid 4 having a support ring 29 and configured to be appropriate for the inner diameter of the dome. the support grid 4 is designed to be removable with all elements of the component fixed together.

The load for the support grid can be calculated according to process requirements.

(029) Figures 1 iA and i lB are further detailed drawings of the slotted pipe inlet 6 showing an embodiment where a baffle 30 is included and wherein Figure Il B is a cross sectional view ten along line A-A of Figure hA. The baffle 30 comprises slots open in the bottom of the pipe. The orientation with respect to first tray 19 is also shown. Figure lB also shows covered areas and free areas of the first tray.

(821) By arranging the degasser in the vertica position according to the invention, good process operation can be accomplished. All of the intervals can be assembled and can he removed and reassembled at different intervals depending on the process requirements.

The operating temperatures and pressures are chosen according to process requirements.

Liquid is easily collected in the bottom of the vertical degasser of the invention. Known inlet distributors can he used and easily installed in a vertical position in the vertical degasser of the invention.

(022) The invention provides many advantages over the degasser of the prior art. In particular, the hay intervals are adjustable and can be used in any process required arrangement and spacing. Liquid drains from the vertical degasser quickly and completely. The vertical degasser has a much smaller equipment footprint than the horizonta' degassers of the prior art and therefore allows for optimization of plant space.

The vertical degasser operates in an effective manner with vapor flowing from bottom to top and liquid flowing from top to bottom. The equipment control is more optimal for operation with space savings, more accessible arrangement of instrumentation, and easy optimization of intervals when compared to horizontal degassers. The vertical degasser of the invention is similar to a cohumnn lay out having a storage sump and mass transfer intervals thereby allowing for easier handling, construction and design following similar column design. The space saving set up of the vertical degasser of the invention can be done on the skirt outside the building thus reducing the load in the building necessary for horizontal degassers, (023) The vertical degasser of the invention is suitable for use in any number of chemical operations, including hydrogen production, ethylene/propylene plants, LNG-plants, etc. (024) It is anticipated that other embodiments and variations of the present invention will become readily apparent to the skilled artisan in the light of the foregoing description, and it is intended that such embodiments and variations likewise be included within the scope of the invention as set out in the appended claims.

Claims (2)

1. What is claimed: I. A degasser for use in a chemical plant wherein the degasser is configured in a vertical arrangement.
2. 2. The degasser of claim I wherein the chemical plant is a hydrogen production facility.