A package multiple pass flexible water tube boiler for converting water to steam. The boiler having an enclosure and diagonally offset upper and lower drums. The drums are connected by a series of staggered or offset water tubes. The water tubes comprise two sets of repeating tubes that are bent to substantially similar but not identical designs. The staggered tube arrangement optimizes heat transfer and minimizes the footprint of the unit.

A package multiple pass flexible water tube boiler for converting water to steam. The boiler having an enclosure and diagonally offset upper and lower drums. The drums are connected by a series of staggered or offset water tubes. The water tubes comprise two sets of repeating tubes that are bent to substantially similar but not identical designs. The staggered tube arrangement optimizes heat transfer and minimizes the footprint of the unit.

A continuous flow steam generator includes a combustion chamber, having substantially rectangular cross-section and a lower and upper combustion chamber region, and has a horizontal gas pass connected downstream of the combustion chamber on the flue-gas side. Gas-tight and gas-permeable peripheral walls of the generator are completely or partly made of steam generator pipes welded together and through which a flow medium can flow, and collectors are arranged and connected to the steam generator pipes such that groups of steam generator pipes connected in parallel form heating surface segments of the peripheral walls. First passage collectors are arranged and connected such that the flow medium from first heating surface segments of two parallel first peripheral walls of the lower combustion chamber region are mixed with the fluid medium from second heating surface segments of second peripheral walls, standing perpendicular to the first peripheral walls, of the upper combustion chamber region.

A carbon monoxide (CO) boiler or steam generator having a water cooled CO boiler floor with screen gas distribution inlet to enhance distribution of CO gas in a CO boiler. Either the front or rear wall tubes of the steam generator form an integral screen and the tubes continue, forming a membraned, gas tight enclosure. The floor has a knee to redirect the incoming waste CO gas up into the integral screen. The screen may be provided with tube erosion shields to prevent erosion of the screen tubes and to control the distribution of waste gas across the plan area of the furnace.

A once-through steam generator includes a combustion chamber, the walls of which comprise vertically arranged evaporator pipes connected to one another in gas-tight fashion by pipe webs, through which evaporator pipes flows a flow medium from bottom to top. The evaporator pipes are combined by upstream inlet collectors to form more intensely and less intensely heated pipe groups. A feed water supply is assigned to respective inlet collectors. At least one regulating valve regulates throttling of the mass flow of the flow medium into the evaporator pipes. To determine a control variable for the regulating valve, temperature measurement device measures outlet temperatures of the flow medium exiting the evaporator pipes. Each of the more intensely and less intensely heated pipe groups is assigned to one of the inlet collectors and to an outlet collector, and each of the outlet collectors has one of the temperature measurement devices.