GB2233392A

GB2233392A - An oil spill prevention pump

Info

Publication number: GB2233392A
Application number: GB8914089A
Authority: GB
Inventors: George William James Bell
Original assignee: Individual
Current assignee: Individual
Priority date: 1989-06-20
Filing date: 1989-06-20
Publication date: 1991-01-09
Also published as: GB8914089D0

Abstract

A venturi or jet type pump comprises a barrel of high melting point material eg. copper or stainless steel, a bronze gauze flame arresting disc, a one-way check valve and an on-off stop cock. The pump is steam or air powered and by creating a partial vacuum in oil tanks on ships, will prevent oil from leaking from them. <IMAGE>

Description

THE O.S.P. PUNP The pump herein described is designed to stop oil spillages from oil tankers and even cargo ships fuel tanks, hence its name O.S.P., standing for Oil Spillage Prevention.

It is basically a venturi pump, either steam or air driven, which can draw vacuum. On the suction side is fitted a check valve and an on-off stop cock. The power supply also has a stop cock. The discharge end is threaded internally to take a barrel. It has a recess onto which is placed a bronze gauze flame arresting disc. This is held in position by the barrel which is screwed into the discharge end. The barrel is made of stainless steel or sheet copper, or any other material of a high melting point, so as not to melt if the exhausted gases were ignited.

As the exhausted gases are very flammable, the pump would be mounted pointing up at an angle away from the deck or other structures. It would not be mounted vertically, as liquid cargo, if accidentally pumped through, could fall back down onto the pump and make it unapproachable to an operator. A long tray or bin for catching any oil would be useful but not essential. The body of the pump itself is made of aluminium or bronze or any other non sparking material. The valves and quick couplers, likewise are made of similar material.

The operation of the pump consists of simply connecting it to the top of an oil tank, at any convenient point, such as the existing pressure/vacuum valves on the top of all cargo tanks, and then drawing vacuum. The P.V. valve may have to be removed (usuallyt6 bolts only) and the end of the flexible suction line connected to the flange, or a heavy duty canvas air tight bag could be placed over the P.V.

valve and the end of the suction hose and sealed.

In Figure B, a cross section of an oil cargo tank is shown.

This one is a full beam tank. S is the sea level, F is the top of the oil cargo, N is the point at which no more oil would leak out if the bottom was open to the sea. The water column SK would equal in weight the oil column KN.

The oil that could leak out (measured at low tide if a vessel is stranded) is the oil in V. If vacuum is applied to the ullage space U, the oil in V is effectively secured to the deck and nothing can leak out.

The design of decks is to take a downward load, which the vacuum would create. However, in some cases, internal stiffening may be required.

If a vacuum of 25 ft of water could be attained, this would give a height of nearly 30 ft of oil that could be secured to the deck. Even on large tankers, in figure B, H plus DF is not as much as 30 ft when loaded.

By simple calculation, height H for any situation can be calculated and then only sufficient vacuum applied to secure the oil to the deck head. For best results, U, ullage should be reduced to zero.

The vacuum could be applied to the tanks of cargo whilst travelling, but this may cause loss of some of the cargo by evaporation.

It could also be activated by a sudden change in volume or pressure inside the tank.

A further refinement would be to have all tanks under vacuum and connected to a single expansion tank (also under vacuum) to allow for temperature expansions and contractions of the cargoes. These could be connected with fixed steel pipes with the O.S.P. pump fitted at one common point and manifolded to draw from any line. Alternately a separate pump could be attached to each line.

The valve is 100% effective for preventing oil leakages from the bottoms of vessels, even when holes are very large.

This is the normal type of damage sustained when vessels run aground.

On side damage, as occurs with collisions it is not 100% effective on large holes. The cargo would not "fall" out, as would be the case in an un-vacuumed tank, but could leak out slowly as water leaked in. A slow exchange could occur.

Drawings Figures A and B attached.

Claims

THE DIL SPILL PREVENTION PUMP : CLAIMS:

1. An oil spill prevent i on pump wherein a steam or air powered venturi pump fitted with a discharge barrel, blow back prevention gauze, check valv@, and control valve, is connected to the top of an oil tank of a ship, to create a control led degree of vacuum to prevent, or minimise loss of oil due to rupturing of a tank.

2. An oil spill prevention pump as tiescribed in claim 1, wherein a copper or stainless steel barrel is fitted in case of ignitioi of discharged gases.

rn oil spill prevention pump as described in claims 1 and 2 wherein the pump has a flash back arrestor gauze fitted.

4. fln oil spill prevention pump as described in previous claims wherein the pump can he connected with spark free quick couplers either via a flexible hose or directly onto the top of an oil tank.

5. An oil spill prevention pump as described in previous claims wherein the pump i@ fitted with a check valve and stop cock, and a control valve on @t@ power supply.