US2575462A

US2575462A - Apparatus for curing building

Info

Publication number: US2575462A
Authority: US
Publication date: 1951-11-20
Anticipated expiration: 1968-11-20

Description

Patented Nov. 20, 1951 UNITED STATES PATENT OFFICE APPARATUS FOR CURING BUILDING BLOC Anthony L. Nugey, Rahway, N. J.

Application February 16, 1949, Serial No. '7 6,723

7 Claims. 1

This invention is an improved apparatus over my pending application Serial No. 685,665, filed July 23, 1946, of making blocks for building purposes and particularly building blocks containing intermingled comminuted materials, such as cinder, gravel, sand, slate, slag fines and cement. An important object of the invention is to provide a simple and efiicient apparatus Where-- by such blocks are produced automatically with a minimum of manual labor, and are cured by the action of moisture, and carbon dioxide in the quantities required and at controlled temperature; while being processed with heat to complete the chemical reactions and to dry the damp blocks to a point where the moisture content is below 30%; so as to render the blocks immediately suitable for constructional uses.

Another object is tov provide apparatus that entails relatively minor expense and yields economical and satisfactory results in a minimum period of operation.

A further object is to provide apparatus comprising a carrier upon which the blocks are supported through a predetermined transitory range of travel within an enclosure charged with the products of combustion by which the final curing of the blocks is efiected; and a block press that shapes the uncured blocks before the carrier receives the same. The enclosure has the form of an elongated casing or tunnel through which the carrier passes. In said tunnel the necessary physical and chemical changes are brought about and the blocks attain a completely cured state by the time they reach the discharge end of said tunnel.

In practice I utilize heat generated in a unit which permits any desirable temperature without pressure; generates as a product of combustion the necessary carbon dioxide to complete hydration reactions of the cementitious material; supplies water vapor also as a product of combustion to cooperate with the uncombined water in the green uncured blocks; and continuously circulates this mixture of gas and vapor, preferably counter to the direction of motion of the blocks on the conveyor, any excess water being removed so that the cured blocks have the proper moisture content and no more.

The objects, features and advantages will more clearly appear from a consideration of the following description taken in connection with the accompanying drawings which illustrate a present preferred embodiment of my invention; and the characteristics thereof are pointed out in the appended claims.

" four, six etc., in number.

On the drawings:

Figure 1 is a schematic plan view of the apparatus used with my invention.

Figure 2 is a perspective view of conveyor and driving means.

Figure 3 is a cross section on line 3-3 of Figure 1.

Figure 4 is a longitudinal section approximately on line 4-4 in Figure l; and

Figure 5 is a cross section on line 5-5 in Figure 1.

The tunnel or casing l enclosing the carrier has a reaction unit 2 disposed adjacent the inlet end of the tunnel. This unit houses an oil burner and discharges hot products of combustion into the tunnel controlled at a high temperature ranging from 180 F. to 225 F. The uncured blocks enter the tunnel after being shaped in a press 3, into which the materials are fed from a mixer 4. The press and mixer are operated by power from any suitable source. The products of combustion, including the water vapor, flow counter tothe direction of movement of the conveyor that carries the blocks through the tunnel.

The inlet end and the outlet end of the tunnel l are provided with suitable swing doors 5 as shown in Figure 4. No leakage of products of combustion from the tunnel will occur; because pressure within the tunnel is no higher than the outside atmospheric pressure. The heat tunnel constitutes a tight chamber or kiln, with removable sections, hinged doors, or windows at selected points in its length to allow inspection 7 of blocks and conveyor and to remove fragments dropped by the blocks in their passage through the tunnel. Such doors etc. are indicated at 6.

The tunnel is not straight but has a zigzag configuration, comprising long straight sections 1, each joined by a curved section 8 to the nextsucceeding straight section. The intake and discharge ends of the tunnel are in proximity, to facilitate the coupling of the reaction unit 2. The straight sections 1 are multiples of two, The conveyor also is in sections, one in each section of the tunnel or kiln and all constituting a single continuous conveyor to transmit the blocks through the tunnel l.

The sections of the conveyor in the straight parts of the tunnel are indicated by the numerals 9 and the sect ons in the curved parts are indicated at ID. The tunnel has a fiat bottom H. supported on legs l2, and having the form of a hollow channel in which conveyor is guided; and

on the upper edges of the sides thereof are angleshaped bars i 3 extending lengthwise to which casing is attached, and also serving as rails or guides Within the tunnel I. The top of the tunnel is shown at I4, and the'conveyor sections move in channel-shaped guides i5, one above the other; the upper being supported on the bottom I l and the lower on cross bars I6 below thebottom and outside the casing I. For this purpose the bottom ll of the kiln may have suitable leakproof openings, or the supporting framework consisting of the legs [2 and cross bars It can be enclosed by boards or plates. The pallets I! that carry the blocks to be processed in the tunnel or kiln l are removable from the conveyor. After cured blocks are removed therefrom at the discharge end of the tunnel, the pallets H continue their movement on conveyor 35 to block press magazine where they are re-used.

The tunnel can be constructed in sections according to any suitable plan, and the straight conveyor sections 9 are operated by any suitable drive mechanisms IS on shafts 19 extending to the outside of the kiln and driven preferably by motors 20. The drive shafts i9 and motors 20 are adjacent one end of each straight section 1 of the tunnel, where one end of the straight conveyor section is located; and each shaft 19 also carries a second drive mechanism 2i to operate the curved conveyor section Ill in the adjacent curved tunnel section 8. At their opposite ends, the straight and curved conveyor sections run in curved guides H). In each curved tunnel section 8 are guide pulleys for the conveyor section 10, as shown at 25, mounted on suitable shafts 26. The arrangement is fully illustrated in Figure 2.

to the cement and aggregates, such as aluminum and potassium sulfate; calcium chloride and aluminum and potassium sulfate; magnesium and Example #1 No admixtures added to cement and aggregates:

Lbs. of chemically combined I-IzO/sack of Portland cement 81670 l8.65 lbs.

Lbs. of CO2 sack of Portland cement 15. 19 lbs.

Erample #2 Adding admixtures comprised of calcium chloride and ammonium carbonate:

The unit 2 has a housing 2 with a section 21 enclosing a fan, driven by a motor 28 and pulleys and belt 29. From the fan section 27 leads a flue 3|! discharging into the outlet or discharge end of the tunnel I. The other end of the housing of the unit 2 has a flue 3! leading to the inlet end of the tunnel. It is connected at the point named to the top of the tunnel I by a short flue 32, which has a damper valve 33 in its top. The flue 3| also has a similar damper 34.

The section 9 of the conveyor in the first straight section I of the tunnel leads from the press 3. The last straight section of the conveyor is driven by a motor 20 near the discharge end of the tunnel. This section of the conveyor delivers to a pallet conveyor 35, operated by the same motor 20, and this pallet conveyor leads back to the vicinity of the press 3, so that workmen attending the press and mixer can also unload the finished blocks, and pile them neatly or transfer them to a truck to be taken away, while the unloaded pallets l'i drop into the press 3 magazine for re-use.

In accordance with my experiments I have discovered that a sack of Portland cement, weighing 94 pounds requires 18.65 pounds of water and 15.19 pounds of carbon dioxide which combine chemically with the cement compounds in the mixture of materials to set the blocks and harden them. The chemical equations are shown in Example 1 below, when no admixtures are added to the cement and aggregates.

v I have also discovered that by making additions Evaporates For proper curing of the green blocks too rapid evaporation of excess water is undesirable since this will affect proper hydration of cement compounds and will cause disintegration of the cured.

blocks.

On the other hand after the curing operation is completed the excess water must be removed otherwise the cured blocks will not conform to the specifications previously named. But while the blocks are undergoing curing operations some of the excess water content is continuously recirculated with the products of combustion thus eliminating the necessity of using any watersprays. But in the initial stages, or in the event there is an insufficient. quantity of water to properly cure the blocks in their passage through the continuous heat tunnel, I may use water sprays which the tunnel is provided with, as shown at 36.

When it becomes necessary to remove excess water from the tunnel, it is evaporated and ex-- hausted by manipulating the dampers shown in Figure 3; closing the damper 34 wholly or partly and similarly adjusting the damper 33, and open-' through damper 31, and maintains the recir euiated heated atmosphere at the-correct temperature. The atmosphere in the tunnel con tains oxygen, nitrogen, carbon dioxide and water vapor. The oxygenand: nitrogen are part oi the incoming fresh air; the carbon dioxide originates from burning the oil fuel, which is principaily carbon and hydrogen, under perfect combustion control.

The nitrogen present in oil mel and that in the atmosphere, mix during the process of combustion, but remain unchanged after combustion, since nitrogen is an inert gas.

. The. hydrogen. present in the. oil fuel combines with oxygen in the air to make water vapor,

which furnishes; the excess moisture. necessary for proper curing of the cementitious compound usecl'in the mixture for the blocks, thereby automatically reducing the quantity of water by the amounts so produced. With perfect combustion, one pound of carbon when burned to carbon dioxide will yield- 14,600 B". t. u. and 3.67 pounds of carbon dioxide, which has a volume of 32 cubic feet. During combustion, each one pound of hydrogen united with 8 pounds of oxygen forms 9 pounds of water vapor.

By burning sufficient fuel I develop enough heat that will maintain the interior atmosphere of the tunnel at any desired temperature ranging from 180 F. to 225 F.; and simultaneously I generate the proper quantities of carbon dioxide (which is the important compound that sets the cementitious material) and water vapor so essential to prevent drying out actions which would cause destruction of the blocks; and where any admixtures are used as shown in Example 2, this materially reduces the quantity of carbon dioxide and water needed for hydration and setting of the cementitious compounds.

The reaction unit 2 can have any shape, but it must include a combustion chamber, a mixing chamber where the products of combustion and fresh air are intimately admixed, and circulation is induced by the fan in section 21, discharging into the tunnel, as in Figure l. The recirculated products of combustion are returned into the,

reaction unit as illustrated in Figure 1 and Figure 3. And when conditions require it, the excess water vapor is exhausted as shown in Figure 3, by closing damper 3 5 and opening damper 33, and the fresh air is admitted to the unit 2 by simultaneously opening damper 31 (see Figure 1) The flow of the gas and vapor in the tunnel is from the discharge end to the inlet and adjacent the press 3, and opposite to the movement of the conveyors 9 and I0. See the

arrows

38 and 39.

By this process, each sack of cement weighing 94 pounds will yield up to 26 eight inch or standard sized blocks, and the blocks will be completely hydrated and set within 120 minutes; as compared to 12 to 20 hours required by all of the old steam induration processes; and unproductived labor is reduced by All breakage is eliminated (this usually runs from 5 to 10% in other processes), all blocks have uniform texture and composition and have a structural strengthranging from 1,000 p. s. i. to more than 1,300 p. s. 1. Also the moisture content of the cured blocks are less than requirements stated in all public specifications.

While the above description sets forth my imstructure and steps in proceeding may be adopted without departing from the principle'er. my in vention.

Having described to be new is:

1. An apparatus for making and setting cement blocks comprising", block-forming means, a. kiln, a conveyor comprising sections forming a continuous conveyor for receiving the blocks and carrying same continuously through the kilnand then out of same, means for'heati-ng kiln comprising a reaction unit having means for deliv-- ering gases of combustion directly intothe kiln at the outlet end and in direct contact with the cement blocks being transported on the conveyor, said unit also being connected to the inlet end of the kiln and having a valve controlled opening to the atmosphere adjacent said inlet end, whereby the carbon dioxide and water vaporof said gases constituting the products of combusmy' invention, what- I believe tion is brought into direct contact with said blocks counter-currently to movement of said blocks to thereby facilitate setting of same.

2; Apparatus of the kind described comprisi g a kiln, a conveyor in said kiln, a housing, means in the housing for generating products of combustion, an outlet flue connecting the housing to one end of said kiln, a fan mounted to deliver from said housing through said flue to said kiln and valved inlet connections at a point separate from said flue between the housing and kiln and between the kiln and the outside air, said ap-' paratus having means for moving the conveyor to carry a load from said point to said end of the kiln.

3. Apparatus of the kind described comprising a kiln, a conveyor in said kiln, a housing, means in the housing for generating products of combustion, an outlet flue connecting the housing to one end of said kiln, a fan mounted to deliver from said housing through said flue to said kiln and valved inlet connections at a point separate from said flue between the housing and kiln and between the kiln and the outside air, said c0nveyor being extended from one end of the kiln to the other, the kiln being returned upon itself so that its ends are in proximity, said apparatus having means for moving the conveyor to carry a load from said point to said end of the kiln.

4. Apparatus of the kind described comprising an elongated kiln made up of parallel straight sections and connecting curved sections at adjacent ends of successive straight sections, said kiln having an inlet at the extremity of one,

straight section and a delivery end at the extremity of another straight section, a conveyor made up of sections in each section of the kiln, a reaction unit comprising a housing having a valved inlet connection with the kiln adjacent the inlet thereof, an outlet flue connecting the housing to the kiln at the delivery end, and a blower fan in the line of said flue.

5. Apparatus of the kind described comprising an elongated kiln made up of parallel straight sections and connecting curved sections at adjacent ends of successive straight sections, said kiln having an inlet at the extremity of one straight section and a delivery end at the extremity of another straight section, a conveyor made up of sections in each section of the kiln, a reaction unit comprising a housing having a valved inlet connection with the kiln adjacent the inlet thereof, an outlet flue connecting the housing to the tunnel at the delivery end, and a blower fan in the line of said flue, the inlet and the delivery end of the kiln being in proximity to each other.

6. Apparatus of the kind described comprising an elongated kiln made up 01: parallel straight sections and connecting curved sections at adjacent ends of successive straight sections, said kiln having an inlet at the extremity of one straight section and a delivery end at the extremity of another straight section, a conveyor made up of sections in each section of the kiln, a reaction unit comprising a housing having a valved inlet connection with the kiln adjacent the inlet thereof, an outlet flue connecting the housing to the tunnel at the delivery end, and a blower fan in the line of said flue, the inlet and the delivery end of the kiln being in proximity to each other, the inlet and delivery end of said kiln having swing-doors normally closing the kiln.

7. Apparatus of the kind described comprising an elongated kiln made up of parallel straight sections and connecting curved sections at adjacent ends of successive straight sections, said kiln having an inlet at the extremity of one straight section and a delivery end at the extremity of another straight section, a'conveyor made of up sections in each section of the kiln, a reaction 8 unit comprising a housing having a. valved inlet connection with the kiln adjacent the inlet thereof, an outlet flue connecting the housing to the kiln at the delivery end, and a blower fan in the line of said flue, each section of the com veyor in a curved section being connected to a section of the conveyor in a straight section, and having a common power unit connected to drive both conveyor sections.

ANTHONY L. NUGEY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date Re. 11,998 Dicken June 3, 1902 695,084 Sturm Mar. 11, 1902 1,028,043 Lunt et a1 May 28, 1912 1,063,899 Westergard June 3, 1913 1,521,233 Davidsen Dec. 30, 1924 1,663,309 Lang Mar. 20, 1928 1,809,628 Johnson June 9, 1931 2,062,642 Darrah Dec. 1, 1936