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               COMMISSIONER'S DECISION

 

OBVIOUSNESS: The claims were refused over the teachings of the

              prior art, although claim 3 with minor amendments

             would be considered as related to patentable

             subject matter.

 

The invention involved storing and handling sulfur. A massive block

was formed with the total base embedded in steam coils. These

coils were used to heat the total base area in a controlled

manner as molten sulfur is required.

 

FINAL ACTION: Affirmed. However some claims will be allow-

              able when amendments are made.

 

                 ********************

 

This decision deals with a request for review by the Commissioner

of Patents of the Examiner's Final Action dated June 28, 1974 on

application 127,640 (Class 201-149). The application was filed

on November 15, 1971 in the name of Hilton A. McCabe and is

entitled "Method of Handling Block Sulfur."

 

The application relates to a method of handling large quantities

of sulfur in massive block form, such as is found in sulfur recovery

plants. Steam coils are placed on a concrete pad onto which molten

sulfur is poured and stored in the form of a block. These massive

blocks may weigh 10 to 20 thousand tons. When it is desired to

transfer the sulfur for shipping, steam is introduced into the

system of coils on the concrete pad, molten sulfur is then with-

drawn and transferred directly into a suitable conveyance.

 

In the Final Action the examiner refused the application for

failing to disclose any patentable step over the following

reference:

 

Canadian Patent

 

618,034                April 11, 1961               Dykstra

 

In that action the examiner stated (in part):

 

It is pointed out that Dykstra describes a method of

obtaining free sulfur in a readily transportable

form from a massive sulfur deposit 12, comprising

melting said sulfur by heating means 34 positioned

near the base of the massive sulfur deposit, with-

drawing the resulting molten sulfur by means of

gravity flow from the vicinity of the base of the

partially melted massive sulfur deposit and placing

said molten sulfur into a suitable container 26,

substantially as defined by the applicant in claim 1.

 

There is no patentable merit in merely stipulating that

the sulfur is melted by "indirect" heating means.

Applicant's attention is again drawn to page 7 of the

above cited Canadian Patent which states, "The bins

26 ... are preferably provided with heating coils 27

for melting the sulfur if it becomes solidified in

the bin. The repeating coils 27 may be of the hot water

circulating type and are operatively connected to

distributor 28". Clearly, Dykstra teaches that sulfur,

whether it be poured sulfur which has solidified into a

massive block, or native sulfur in an underground

deposit, may be rendered molten not only by direct

contact by high pressure steam, but also by means of

indirect heating means as proposed by the applicant.

 

The fact that the claims call for a poured massive block

of sulfur at ground level does not render the claims

patentably different from the teachings of Dykstra. To

merely elect whether sulfur will be stored below, at, or

above ground level is a matter of design expediency and

involves no inventive ingenuity.

 

In applicant's letter of April 9, 1974, it is argued

that in Dykstra's case, all of the sulfur must not only

be melted before he removes it from the pit by means of

a pump, but the entire batch of sulfur must be maintained

in molten form, whereas the applicant is concerned with

heating the base of the sulfur block and removing the

molten sulfur from the base of the block by gravity

drainage.

 

However, there is nothing in Dykstra's disclosure to

support the applicant's contention that the entire batch

of sulfur in storage bin 26 must be maintained in a

molten state before sulfur may be removed from the bin.

Dykstra shows the intake conduit of pump 30 extending

downwardly to the base of bin 26, and it is reasonable

to assume that pump 30 may be operated to withdraw molten

sulfur from bin 26 well before all of the sulfur is melted

by the heating coils.

 

The applicant in his response dated September 10, 1974 to the Final

Action stated (in part):

 

...

 

Specifically, Claim 1 includes the manipulative step of

"melting said sulfur by indirect heating means at the

base of said block." In order to argue that this step is

taught by Dykstra, the Examiner has subdivided the explicit

wording of applicant's step into three subelements and then

proceeded to correlate these subelements with separate

points in Dykstra's process.

 

The "said sulfur",a "poured massive block", is equated

to the offshore sulfur deposits discussed in Dykstra.

This correlation is legally inaccurate in that the two

expressions do not read on common subject matter and

technically inaccurate in that applicant's invention

involves remelting a free-standing massive block of

sulfur while Dykstra is extracting sulfur which is

naturally entrapped in a honey-combed limestone deposit.

 

The second subelement in the Examiner's analysis involves

identifying the applicant's act of "melting... at the base"

as being synonymous with Dykstra placing a heating means

near the base of the massive sulfur deposit. Again this

is inaccurate. Applicant's invention as explicitly worded

is restricted to the act of melting the sulfur at the base

of the block exclusively. 1n other words, the melting

occurs at the interface of the indirect heat exchanger and

the free-standing block resting on the heat exchanger. As

the block melts it falls and a new base comes in contact

with the heat exchanger. In contrast, Dykstra's process

inherently involves the drilling of a vertical shaft from

the underside of the sulfur deposit up into the deposit.

The fact that the Frosch type heating means is placed near

the base does not amount to the claimed manipulative step

of melting at the base. In the Dykstra process the

entrapped sulfur does not flow to the base until after the

hot steam has come in direct contact with the sulfur. In

other words, the act of melting in the Dykstra process

occurs exclusively within the honey-combed limestone matrix

and not at the base of the deposit.

 

The third subdivision of the aforementioned novel step

involves equating the indirect heating of applicant's

invention with the heating coil in Dykstra's storage bin

located downstream from the melting step. To argue that

the intended use of this reservoir is for crystallizing and

remelting of sulfur is inaccurate. By Dykstra's own

admission, this heating coil is merely preferred (optional)

and is used to melt the sulfur if it becomes solidified.

Thus the clear intent of this heating coil is to sustain

the sulfur in a melt state. The obvious purpose of having

Dykstra's storage bin is that it acts as a surge tank on the

inlet side of a pump to account for upstream variations in

flow (a well recognized engineering principle). To further

emphasize this point, please note that applicant's drawing,

Fig. 2, shows a surge tank prior to the pump; applicant also

teaches the advantage of heating downstream from the melting

to prevent freezeup, and that these elements are remote from

and are not part of the claimed improvement.

 

Hence, applicant's basic position is that Dykstra does not,

in fact, perform the melting step as explicitly stated in

applicant's claims. Further, Dykstra does not teach the

combination of subelements selected from remote areas of his

overall process. He does not teach this combination into

two senses. The first is that combining of these subelements

would create a manipulative melting step which would be

inoperative with respect to the purpose of h.is disclosure;

i.e., you don't remove sulfur from natural deposits by indirect

heating. The second is that Dykstra does not disclose the

specific advantages of the combination, particularly

applicant's observations of reduced sulfur dust emissions and

improved heat flux efficiency.

 

The Dykstra citation relates to a method of extracting and recovering

sulfur from earth bearing sulfur deposits. Claim 1 of that patent

clearly sets forth the method and reads:

 

The method of extracting and recovering sulfur from a

sulfur deposit surrounded by a competent formation

submerged under water, said method comprising the steps

of sinking a substantially vertical shaft into said

competent formation to a point below the bottom of the

sulfur deposit, installing a watertight casing from at

least the top of said shaft to a point above the wave

level of the water, forming at least one substantially

horizontal tunnel from a point near the lower end of

said shaft to the boundaries of said sulfur deposit at

a level below said sulfur deposit in the competent

formation, extending at least one small-diameter shaft

upwards through said competent formation into sulfur

body thereabove, installing a pair of pipes in said

shaft in communication between said, tunnel and said

sulfur deposit, pumping hot fluid up one of said pipes

into said sulfur deposit to melt the sulfur therein,

flowing the molten sulfur down the other pipe to said

tunnel and removing the sulfur from the tunnel up said

shaft to storage means at the surface.

 

The applicant also sets forth the state of the art in his disclosure

on page 1, second paragraph, which reads:

 

Sulfur has been stored principally in two different

forms, in blocks and in piles of loose flakes. The

block sulfur is formed by pouring molten sulfur into a

low, rectangular form and as the level of the liquid

sulfur approaches the top of the existing sides, an

additional section of sideboards is placed around the

top of the edge of the original form, preferably in

liquid-tight relationship therewith. By following this

procedure large blocks of sulfur weighing several thou-

sands of tons are formed, and while such method of

storage requires a minimum of spacing, the block has to

be broken by the use of explosives when it is desired to

remove sulfur therefrom. Considerable dust is formed during

this process, requiring those in the vicinity to wear

special industrial masks. Sulfur is also stored in

flake form in large piles. Flake sulfur is produced by

placing it in molten form on an endless belt, one end of

which is submerged in water. When the molten sulfur

contacts the water it solidifies and breaks up into flakes

as the belt passes over and around the end roller. Sulfur

in this form can be readily loaded into gondola freight

cars; however, such a loading operation is undesirable

because it also generates large quantities of sulfur dust.

Flaked sulfur has an additional disadvantage when stored

on the ground, i.e. the pollution problem created due to

rain percolating through the pile since run-off therefrom

is very acidic.

 

As mentioned, the application relates to a method of handling large quanti-

ties of sulfur in massive block form in sulfur recovery plants. The block

is formed by pouring molten sulfur into a form at the base of which are

located steam coils. These massive blocks may weigh 10 to 20 thousand

tons. When it is desired to transfer the sulfur for shipping, steam is

introduced into the system of coils on tile concrete pad, molten sulfur is

then withdrawn and transfered directly into a suitable conveyance. Claim 1

reads:

 

In the method of obtaining free sulfur in a readily trans-

portable form from a poured massive block thereof at ground

level, the improvement comprising melting said sulfur by

indirect heating means at the base of said block, withdrawing

the resulting molten sulfur by means of gravity flow from the

base of the partially melted block and placing said molten sulfur

into a suitable container.

 

The question which the Board must consider is whether the applicant has

disclosed and claimed a patentable advance in the art.

 

In the applicant's view there was a problem in the storage and handling of

large quantities of sulfur in massive blocks. The specific problem was

one of removing a portion of the sulfur from the massive block. According

to the applicant the removal of a portion of the sulfur was normally

carried out by using explosives, accompanied by the usual nuisances and

precautions which are necessary in a procedure of this kind.

 

The applicant maintains that he has overcome that problem by forming the

block in a special manner. The molten sulfur is poured into a form at the

base of which are located steam coils. When it is desired to transfer

the sulfur for shipping, steam is introduced into the system of coils to

melt .the lower portion of the massive block; this molten sulfur is then

withdrawn by gravity and transfered directly into a suitable conveyance.

Generally, it is preferable to have a higher concentration of coils or

heating pipes near the center of the sulfur block. That arrangement aids

in increasing the melting rate of the center portion of the block,

results in desired stress toward the center of the block, and minimizes

the tendency of the block to crack during the melting operation. Further-

more, throttling valves may be used to adjust the heating rate, so that

the stresses in the block due to uneven melting can be controlled.

 

There is no reason to disbelieve the applicant s claim that he has overcome

a problem in the storage and handling of massive blocks to molten sulfur.

The specific issue, however, is whether his solution involved such an

exercise of the creative faculties of the human mind as to merit the dis-

tinction of invention, or a claim to monopoly. It has been authoritatively

stated that the art of combining two or more parts, whether they be new or

old, or partly new and partly old, so as to obtain a new result, or a

known result in a better, cheaper, or more expeditious manner, is valid

subject matter if there is sufficient evidence of thought, design, and

skillful ingenuity in the invention, and novelty in the combination.

(See Merco Nordstrom Valve Co. v. Comer (1942) Ex. C.R. 138 at 155.)

 

The applicant has argued that the examiner has subdivided the explicit word-

ing of applicant's step (of claim 1) into three subelements and related them

to separate parts in Dykstra's process. There is, however, nothing objection-

able in analysing a claim to ascertain whether the prior art teaches the

different steps. A claim must then, however, be scrutinized as a complete

combination to ascertain whether there is invention in the new combination,

whether it produces a new result, or a known result in a more expeditious

manner, even though all of the elements be old (see the discussion in the

previous paragraph).

 

We now consider the claims.

 

In claim 1 the alleged improvement is stated to be "melting said sulfur by

indirect heating means at the base of said block, withdrawing the resulting

molten sulfur by means of gravity flow from the base of the partially melted

block and placing said molten sulfur into a suitable container." It is

well known in the art (as taught by Dykstra) to use heating means to melt

a body of sulfur, and then remove the molten sulfur by gravity flow into

a suitable storage container. In Dykstra's arrangement the stored molten

sulfur is also kept in a fluid state in the container by an arrangement

of heating coils. The preparation of a poured massive block of molten

sulfur such as that melted in claim 1 was also known previously (see page 1

of the present disclosure). To merely apply heating means to the base of

a known block of sulfur does not involve an inventive step.

 

In our view certain essential features are missing from claim 1. First the

block is poured in a special manner, i.e. the molten sulfur is poured into

a form, on a concrete slab, at "the base area of which are located heating

coils." It also omits reference to the fact that the heating means are

applied to the "total base area" of the block, and in a "controlled manner,"

Claim 1 is too broad in scope in view of the prior art, and in our view

is also broader than the invention disclosed.

 

Claim 2, which depends on claim l, adds a particular heating means as a

limitation. This does not introduce anything of patentable significance to

what has been defined in rejected claim 1.

 

Claim 3, which depends indirectly on claim 1, introduces further limitations:

"... said block is formed by pouring molten sulfur into a form at the base of

which are located steam coils adapted to control the amount of heat available

therefrom to said base (area)" (emphasis added). The block formed with the

heating coils embedded in the base and the control means to heat the "total

area" of said base, or possibly to a given area of the base, are essential

features and must be included in any allowable claim to the new process.

 

This claim (3), therefore, if amended as to form and clarity, and rewritten

in independent form (including the necessary steps of claim 1,) would,in our

view, express some element of inventive ingenuity for there is no teaching

of handling stock piles of sulfur in this manner. It has been held that a

"mere scintilla" of invention will suffice for the validity of a patent (The

King v Smith Incubator 1935 Ex.C.R. 105 at 112), and simplicity is not in

itself an impediment (Adams and Westlake v. Wright, 1928 Ex. C.R. 112 at 115).

Viewed in that light, the benefit of doubt should be weighed in favour of

the applicant. Should any amendment be made, the steps of the process should

be recited in correct sequential order. It should also be made clear that

the "form" for the block includes or has in addition to it "a slab or base"

as a foundation for the sulfur block, and a heating control applied to the

"total base area."

 

Claim 4, which depends on claim 3, adds a heat control unit. It would be

allowable if dependent on a revised claim 3.

 

Claim 5, which depends on claim 2, is directed to recesses in the base support-

ing the block. This is not a patentable feature in itself, but the claim

would be allowable if dependent orb an amended claim 3.

 

We are satisfied that claims 1, 2 and 5 fail to include the necessary essential

elements of a patentable advance in the art. We are also satisfied that

claims 3 and 4 are directed to a patentable invention, but require amendment

to define the invention explicitly. The feature added in claim 5 could also

be protected if made dependent upon a modified claim 3.

 

The Board recommends that the decision of the examiner to refuse the claims

on file be affirmed. Since by appropriate amendment it is possible that

some subject matter might be accepted, we do not recommend rejection of the

application itself.

 

J.F.Hughes

Assistant Chairman

Patent Appeal Board

 

I concur with the findings of the Patent Appeal Board and refuse the claims

of this application. The applicant has six months within which to present

a new claim (or claims) drafted along the guidelines indicated, or to appeal

this decision under the provision of Section 44 of the Patent Act.

 

Decision accordingly,

 

A.M. Laidlaw

Commissioner of Patents

 

Dated at Hull, Quebec

this 5th, day of

June, 1975

 

Agent for Applicant

 

Gowling & Henderson,

Ottawa, Ontario.

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