Energy from Waste - Double Flap Valves

European Gate Valves Ltd has completed a number of contracts for the Energy from Waste industry.

The valves supplied have successfully overcome premature wear and performance problems which beset rotary valves previously fitted.

Primary Cyclones

The valves are installed on the discharge of the primary cyclones in the flue gas cleaning circuit. The sensitive nature of the cyclone to bottom up air flow due to leaking valves is well known and is no longer a problem due to the superior sealing efficiency of the Double Flap Gate Valve.

Bagfilter. ESP

A number of valves have been installed on pneumatic conveying lines used to convey ash discharge from the bag filters and Electro Static Precipitators to an ash reception silo. Despite rotary valves being specified as abrasion resistant, they have still developed loss of performance within a few weeks. This includes accelerated wear leading to leaks and lower throughput, necessitating costly overhaul and repair with eventual complete valve replacement.

Heavy Ash Drop Out Box

For many plants the problems of the combined effects of abrasion and temperature when operating a valve as a seal is the clearances necessary to accommodate expansion in the valve results in very poor sealing efficiency. With Double Flap Gate Valves this is not a problem. With a ground flat plate meeting a ground flat seat a perfect seal is maintained across a wide range of temperatures. With typical temperatures of 300°C to 400°C the European Gate Valves double flap valve becomes the logical and sometimes only choice.

Due to the design, double flap gate valves offer further savings. Replacement of any wear parts can be easily carried out through access covers, without the valve being disconnected or removed from the process line.

Double flap valves are robustly manufactured to suit a wide range of application requirements:

Valve Bodies can be made in: Cast Iron, Cast High Nickel Chrome and Cast Aluminium

Fabricated bodies made in Carbon steel or Stainless Steels

High chrome alloy seats and flaps provide long life even in the most aggressive applications

Range of Applications:

Temperatures to 1000°C

Differential pressures to 102 Kpa where positive is below

Abrasiveness - Some of the most abrasive materials are comfortably handled

Lump Size - Depends on the valve opening size

Opening to 600mm square

Range of actuators:

Linear Pneumatic Cylinders

Rotary Pneumatic Cylinders

Electric Motor with cams or push rods

Gravity or Manual

Hydraulic

Features:

Dual access covers

Outboard Bearings

Adjustable packed shaft seals as standard

VDMA ISO standard cylinders

Removable seat and flap with the valve in situ

All metric standard components

Wide range of optional equipment:

PLC Control

Flap position indication

Heat shields

Cooling for high temperature applications

Purged high efficiency shaft seals